Note: Descriptions are shown in the official language in which they were submitted.
9~
. .
I
BACKGRO~ND OF THE INVENTION
I
The present invention relates to a new and im-
proved method of, and apparatus for,surface or terrain and
1'l space monitoring by means of pulsed directional beams.
:~ '
There are already known to the art different
types of light barriers, such as for instance disclosed in German
Patent Nos 2,157,815 and 2,129,666 and German Patent Publication
No. 2,353,702, which can be employed for monitoring, against un-
authorized intrusion, certain sùrfaces, terrain or spaces or
areas. Such systems prcvide intrusion supervision along a
periphery, however only along linear paths.~ Additionally, they
are afflicted with the drawback that the equipment needed for
such purpose must be erected at the periphery of the monitored
terrain or space or the like. Hence, it is possible by, for
instance, intentionally or maliciously tampering with the equip-
ment to impair its effectiveness, or else by caref~lly observing
~,
" j . :~
~; ""' -2
`i~
:,: - :
:
,
j~ ll Z9978
the functioning of the system to take counter measures for fool-
; ~ ing the same. There have also been proposed in the art space
monitoring systems wherein, at a space which is to be supervised
or monitored, there is produced a radiation field. Sensors are
provided which are responsive to field changes, as the same are
caused bv objects, such as intruders, invading the space or area
and, in consequence thereof, trigger an alarm. Significant in
I this regard are the following prior art references: German Patent
Publication No. 2,346,764, German Patent Publication No. 2,508,796
- 1~ German Patent Publication No. 2,600,362, German Patent No.
2,613,375, German Patent No. 2,617,467, German Patent No. 2,638,
; 337, German Patent No. ~,656,256, German Patent Puhlication No.
2,702,499 and German Patent Publication No. 2,722,982.
.',, . .
Prior art methods and equipment are capable of
satisfactorily accomplishing certain objectives or tasks. How-
ever, as a general rule they are afflicted with the drawback'that,
~ ~ if they are set to possess ade~uate sensitivity, apart from
¦ ~ tripping the desired alarms, thsy also can be caused to trigger
. :
false alarms by~ the actlon of some other effects. Such system
operatlon is, however, unsatisfactory on a continuing basis,
since upon frequently triggering false alarms the confidence in
the reliabili~y of such method and its equipment oftentimes is
;~so shaken or impaired that, with~time, there is a tendency not
to take too seriously the~triggering o~ an alarm.
, ` ~' .
~ 3~_ I
:,.: : , . .
~, .:
;~. .,
SU~MARY OF THE INVENTION
Therefore, with the foregoing in mind it is a primary
object of the present invention to provide a new and improved
construction of intrusion method and apparatus which is not
readily susceptible to triggering of false alarms, possesses
high integrity in monitoring a region, meaning a surface, area
or space or the like which is to be supervised or protected,
and operates in a manner that it is extremely difficult to
fool the monitoring method and e~uipment.
According to the invention there is provided a method of
monitoring a region by means of pulsed directional radiation,
comprising the steps of: fixing certain points in space to
define at least one virtual line or virtual surface; dividing
~:. a surface into partial surfaces by means of said virtual line:
: or a space into partial spaces by means of said virtual sur-
; 15 face; assigning a respective predetermined significance to
:' each said partial surface or partial space; utilizing measur- -
ing means possessing a substantially punctiform expanse at
the virtual line or virtual surface or at an object to be
. detected, transmitting the measuring beams in defined direc-
tions; and determining by means of the transmitted measuring
,
beams at least one parameter for the identification of at
least one object.
~, . .
~ An advantage of the present invention, at least in
.; :
preferred forms, is that it aims at~the provision of a new
and improved method which affords an extremely reliable
"
4 --
-:,
,
. ~ . ~ ,~, .
.,. ~ , .
: ,
, .
: ~ . , - , , -:,
:
~g~
surface, terrain, area or space monitoring, essentially is
immune against intentional attempts to impair the function
and operational integrity of the equipment, additionally,
notwithstanding its extremely high sensitivity has an
exceptionally small rate of triggering false alarms, and
further, also is suitable for monitoring relatively com-
plicated structures or configurations of surfaces, terrains,
areas, spaces or the like.
Another significant advantage of the present invention,
;: 10 at least in the preferred forms, aims at the provision of
a new and improved construction of intrusion protection
apparatus which is extremely reliable in operation, not
~ readily subject to breakdown or malfunction, requires a
minimum of maintenance and servicing, while affording high
.15 security against unauthorized intrusion into a protected
region, whether such be a surface, terrain, area, space or
room or the like, and wherein the system design is such that
it is virtually impossible, but at the very least extremely
difficult, to undertake counter measures for fooling the
equipment and its mode of operation.
In the context of this disclosure and especially the
.claims the term "space" or "region", whenever the context
permits, is used broadly to encompass surfaces, areas, ter-
.~rains, expanses, rooms or the like, which are to be monitored
or supervised.
~,
:Preferably, the inventive method for space monitoring
~ :by means of pulsed directional beams is manifested by the
`,,`.~:
- 5 -
: :
. . .
, -,
.
- '
~ ' ' .
, ~ .
97~
.~
features that, there are determined certain points in the
space and there is thus defined at least one virtual line
or virtual surface. By means of such virtual line or
virtual surface a surface is split or divided into partial
surfaces or a
,
~'
:~
,
~,
.;
.
:,
i.~
:
,., :
~ 5a -
, ~ :
. ~ , ,
;
, . ", " ,. . . . . .
, ., , - . .
:: , , , . , ~ . ~. ,. . ~, . ,
:: i , .
~ g7~ ' I
space into partial spaces. These partial surfaces or partial
spaces each have allocated therewith a certain significance. By
means of measuring beams which possess a point-shaped or puncti-
form expanse at the virtual line or virtual surface or at an
object to be detected, there can be directly or indirectly deter-
mined at least one parameter for identification of at least one
object, and the measuring beams are transmitted in deflned
directions.
'.`
As mentioned previously, the invention further
I concerns novel apparatus for the performance of such space
monitoring or supervising method, wherein there is provided a
directional beam emitter comprising a pulse transmitter for
transmitting pulsed directional beams in defined timewise sequence
and defined directions. A receiver is provided for the spatially
directed reception of reflected energy of the directional beam
transmitted by the directional beam emitter. A computer serving
as an evaluation devLce mathematically evaluates a multiplicity
of reflection signals which have been received from different
dlrectlons and/or reflection signals which should ~have been
refleoted but have not appeared. ~
The invention explolts the general inventive concept
of continously measuring a surface region, terrain, space or area
to be monitored, as mentioned generally simply generically referred
. ~ `
f :: ~ : ` ~ ::
~ ~ f~ ~ - 6 -
: ~,, :,. ... , .. ~ . " , ,
: ~ , . . . .
: ~ ,
.:. '
~' ~ ' "' ' .
; ~2~9~E~
to as a region or space, as concerns its condition and possibly
, arising changes. The obtained measuring results are evaluated,
for instance compared with stored values. The measuring results
also can be further processed, so as to thus obtain additional
information, and this additionally obtained information can be
compared with stored information, to thereby not only reliably
determine changes which have arisen, but also to be able to
evaluate such as concerns their position, nature and significance,
for instance in order to only then trip an alarm when a detected ¦
~0 change fulfils certain criteria.
' . . I
In this way there is not only insured for reliable
and exact dstermination of the condition and changes in condition
of the monitored space, but it is also possible to limit the
~ detection to certain objects or events. Consequently, it is
; possible to extensively avoid the bothersome frequent tripping of
false alarms which arise with other state-of-the-art systems.
~. . I
The method and apparatus for the performance there-
of, as contemplated by -the inventlon, have been found to be excep-
~ tionally immune against intentional counter measures for fooling
; the system, since the system parameters practically cannot be
recognized or detected from externally, and cannot be influenced
or fooled by external measures. Addltionally, the equipment,
in coneras to the afore~Gn~iored lig~- ba-riers, significantly
- 7 -
' ~; ' ' ,-
,
,: . ' ' . . :
~ 9~
is not erected at the peripnery or outer contour of the surface,
region, space or area to be monitored, in other words, a super-
vised space, rather is arranged practically at the center or
at least within the monitored region. Due to the relatively
small and compact construction of the equipment and its compara-
tively large spacing from the periphery of the monitored reyion,
it is easy to disguise or camouflage, and thus, it can be pro-
tected against intentional or malicious tampering from a distance
or remotely.
The method and apparatus of the invention are not
only effective for monitoring the most different spaces or the
like, such as suraces, terrains, areas or rooms, against distur-
bing, especially malicious or intentional intrusion, but also
can be beneficially employed for other significant purposes, such
as, for instance, for the continuous monitoring or supervision
of terrain which tends to move or shift, such as land slides,
earth movements and so forth, important structures or constructior
sites such as dams, all for the purpose of detecting changes
which arise thereat. Also, the monitoring equipment and method
is extremely suitable for safeguarding against burglary or other
unauthorlæed intrusion into buiLdings or struotures, such as
houses, buildings, factories, plants,military installations and
so forth, by virtue of its relatively uncomplicated construction
and its extremely~great flexibility concerning its field of ap-
pl~cation with respect to ditf~rent types of structures. Due to
~' : ~: ~: '
', ~ . ~ ~ ~
,
'
gl ~Z9~
the high resolution capability of the system and the rapid
mode of operation thereof, it is equally possible to detect mov-
ing objects and their behavior reliably and with extremely great
accuracy.
BRIEF DESCRIPTION OF THE DRAWINGS
. . ~
The invention will be better understood and objects
other than those set forth above, will become apparent when
consideration is given to -the following detailed description
; thereof. Such description makes reference to the annexed draw- ,
I O ings wherein: ¦
. , ..
Figure 1 is a plan view of a region to be protected,¦
such as a surface or terrain, showing a possible arrangment of
warning zones externally of a protective zone by means of virtual
: lines;
. .
Figure 2~is a perspéctive view showing the con- ¦
ditions prevailing wlth space monitoring with virtual surfaces
; for forming warning areas and a protective area;
:' ': ' I
Figure 3 illustraies an~example of measuring a
: moving object within a terrain;
. . ,
: ~ :
~ ' : _ g _
. ~ ~ . ,
. :
: ~ - ' , - '
- . .. j -
,
: ~ ~ : ' ,' ,
, :
~ 7~
Figure 4 is an elevational view illustrating dir-
ectional beams and virtual surfaces;.
'7 ~
Figure 5 is a sectional view of a directional beam
emitter usedin practising the invention;
Figure 6 is a block circuit diagram of apparatus
for performing the method;
.
I
Figure 7 is a schematic elevational view of a
measuring beam course during the fixing or determination of
: certain virtual surfaces;
~ s~ . ' I
Figure 8 is a schematic plan view showing the course¦
of measuring~beams during the fixing or determination of certain
virtual surfaces;
Figure 9 shows an arrangement for region or space
monitoring~employing a beam sp~itting system;
Lgure 9a illust~ ~tos a detai~ of the arrangement
f Figyle 9, ~ ~
Fig~ure 10 is a block circuit~diagram~of an exemplary
........ ...
: , .
~Z~ 378
Figure 11 schematically illustrates the serial
evaluation of distance vectors; and
Figure 12 schematically shows the groupwise evalua-
tion of distance vectors.
DEIAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
Describing now the drawings, in Figure 1 there is
shown a region to be supervised or monitored, illustrated for
instance as a terrain or surface 1 which is-bounded by a line 3
emanating from a point 2, a line 4 and a line 5 which leads back
to such point 2. Figure 1 illustrates such region, hereinafter
simply generally referred to as the terrain or surface l, in plan
view. The line 4 extending between the boundary lines 3 and 5 is
to be understood as constituting a virtual line, which does not
appear physically withln the terrain l, yet is defined or fixed
as far as its course or extent is concerned by data stored in a
storage or memoxy, for instance by the polax coordi-nates of a
., :
number of points selected to lle upon such line 4 and related
to the polnt 2, for~instance;the~polnts~6 to~ 16. Between these
selected points 6 to~16 the cour6e of the virtual line 4 can be
24 determined, for instance, by linear lnterpolation by means of
a computer or according to a predetermined functionj as will be
explained~more~fully hereinafter. ~The second virtual line 17 -
can be freely chosen, for lnstance in a freely selectable,
. ~
:
` " ~ ~ : , ,, , I
~ , . . .
.
.. . .
.:: .
~LZ9978
preferably constant spacing from the first virtual line 4 in
the direction of the point 2.
,~ e
. A third virtual line 18 likewise can be freely
chosen, for instance in a further freely selectable, preferably
constant spacing from the second virtue line 17 in the direction
of the point 2. By means of these virtual lines4, 17 and 18
the surface area of the terrain 1 is divided into partial sur-
faces 19, 20 and 21, each of wh.ich can have allocated thereto a
certain meaning or significance. Thus, or instance, the partial
surface 19 may constitute a first warning zone, the partial
surface 20 a second warning zone, and the partial surface 21
a protective zone. Each of the aforementioned partial surfaces
19, 20 and 21 therefore ad~antageously has allocated thereto
a pr`edetermined significance.
:
The point 2 constitutes the erection site for a
directional beam transmitter to be considered more fully herein-
: : : after, which, or instance, radiates narrowly focused electro-
magnetic radiation, for instance invisible light pulses of a
: laser light source, ln a time sequence in different directions
~ towards the terrain 1. Each of these pulses is radiated or
' .
~ transmitted at a defined point: in time and in each case at a
;~ defined azimuth angle ~and elevation angle'~in the terrain 1.
: , , ~ :
~ -~ - 12 -
:~: :
., ~ :
' ,'
-\
Point 2 also constitutes the erection site for a
radiation receiver, also to be discussed more completely herein-
after, which, from the momentary direction of a radiation or
beam pulse, preferably by being spatially and fre~uency selective
to incoming radiation, i.e~ reflected radiation, responds and
evaluates such received reflected radiation. By means of each
such transmitted beam pulse there is formed, in each case, a
certain measuring beam which, as the case may be, is reflected
at an object or by the terrain as the background. As a matter
of convenience in this disclosure such measurin~ beam associated
with a reflection will be designated as a direct measuring or-
measurement beam. On the other hand, if there does not occur
anv refle~tion, for instance because of complete or practically
complete radiation absorption or because the transmitted beam
or radiation is reflected or deflected away in another direction,
then such measuring beam will be referred to hereinafter as an
indirect measuring or measurement beam. As will be demonstrated
more fully hereinafter, even in the event of indirect measuring
beams, i.e., the absence of radiation reflection back to the
receiver, it is possible to obtain signlficant information as
concerns the condition of the monitored or supervised terrain,
i.e., generally the region or space.
.
Based upon the showing of Figure 2 there will be
explained the conditions which prevail during the determination
or fixing of certain points in a space or region for the definition
.. , :
.
,
: . ~
~ . ~ ~ ~L129978
of virtual surfaces at the space. The point 2 at the space has
been chosen, as mentioned, at the site of erection of the direc-
, tional beam transmitter. A space sector or region 22 extends
outwardly from point 2. Its angular limits are defined by
fixing certain points in the region or space, for instance by
points 23, 24, 25 and 26. By means of these points 23, 24, 25
and 26 and possibly further points, for instance the points 27
and 28 and even further points, it is possible to define a
randomly extending surface as a virtual surface 29 in the space
or region 22. The spatial extent of the virtual surface 29 canbe fixed between the aforementioned defined points by interpola-
tion based upon a predetermined functional correlation. In
corresponding manner it is possible to define further virtual
surfaces, for instance by fixing the further points 30, 31, 32,
33, 34 and 35, and, if desired, with the aid of additional points,¦ -
a second virtual surface 36.
. ' ~~
The virtual surfaces 29 and 36 have each been illustra-
ted in Figure 2 by a line grid or network.
The determination or fixation of the aforementioned
points can be accomplished, for instance, by coordinates of each
such point related to the coordinate system x,y,z, or by polar
coordinates. These coordinates are stored in a suitable storage
or memory. The aforementioned virtual surfaces 29 and 36 there-
fore do not physically appear in the space or region,they are
- 14 -
, . . . .
':' ' , :` ' :
' , ' : '
~Zg97~ 1
so-to-speak "imaginary" surfaces, by means o~ which it is pos-
sible to divide the space sector 22 into partial spaces or
regions.
Each partial space has allocated thereto a certain
significance. For instance, the outermost partial space 37 may
be considered to constitute a pre-warning space or region, the
intermediate partial space or region 38 a warning space, and the
innermost partial space or region 39 a protective space. With
a predetermined sequence of measuring beams, defined as a
~0 function of time and in relation to azimuth and elevation, and
which beams emanate from the erection site or point 2 of the
directional beam transmitter, there is scanned and measured
the space sector 22. An object 40 located in the space sector
22, or, in the case of a larger size obiect a portion thereof,
will be impinged once or repeatedly by measuring beams of a
predetermined direction. Each measuring beam is a narrow
radiation beam, the cross-sectlon of which at the object or at ¦ -
the virtual surfaces, can be considered to be punctiform or
~ ~ point-shaped. Thus, under the expression "punctiform" or "point-
; shaped" it is to be~understood that the cross-sectional area
of-the beam lS small~ln~relation to the dimensions of the object
~to be detected. Thls aIso means that the smallest possible
~cross-sectional area also can be consldered to be punctiform
; lf the object to be detected is~even smaller. However, in
this case it is not possible to make any statements concerning
;
15- 1`
: ~, :,
::
' '""' '' ' ' ~' '- '' ~ '`'''`' '
, 1 . . ., ~ . ... . . .. . ....... . . .
., ~ , . . - ~ . .
,: ., : -,. . ; .
., , - , ; ,
. .
.~
~, . . , . . ~ . , .
.
~ 7~
the actual size of the object, although the object still remains
discernible.
At the receiving end of the system it is possible,
by measuring the travel or transit time of the beam or radiation
between the directional beam emitter and the object 40 and back
again to the receiver, to determine at least one parameter, for
instance the distance of the object from the directional beam
emitter.or the location of the object. Based upon the timewise
sequence of the measuring beams and their azimuth angle and
elevational angle, and thus, the different measuring values, it
is possible to directly detect an object 40 (Figure 2) and/or
its shape. -I~ there is located within the monitored space or
region an object having a surface which practically completely
absorbs the radiation, then, due to the sudden absence of
radiation reflections at the background it is nonetheless pos-
sibIe in an indirect manner to determine the presence, the an-
gular position, the shape and further information concerning
such:object by processlng the direct measuring beams from the
immediate neighborhood of such object.: The same considerations
are analogousl~ valid even:when monitoring a terrain or surface
as indicated in Figure l.
: ~ ,~
Since the mentioned vlrtual.lines 4, 17 and lB
.~ : (Figure l~ and the mentioned virtual surfaces 29 and 36 (Figure
: :
2) are defined by sto~ing correlated coordinates or by in~polation
: ~ : , : ,
~ ' .
~ . - 16 -
~ , ' ,:
.
~, . - , ~
,
',
~95s7~ 1
computations based upon functional correlations, they can ~e
defined either fixedly at the terrain or at the space. The
coordinates are then constant values related to the direction
site or point 2 of the directional beam transmitter, or they
also can have a position which varies as a function of time by
the input to the storage of appropriate values varying with
time.
The erection site or point 2 of the directional
beam transmitter can be variable as a function of time, i.e. the
directional beam transmitter can be movable with regard to its
coordinates. Also, in this case, the coordinates of the virtual
lines or the virtual surfaces, now related to the movable point
2, can be constant or, however, variable as a function of time.
Such timewise variations of the virtual lines and
virtual surfaces make it exceedingly difficult to carry out any
operations or manipulations which possibly might intentionally
fool the monitoring system, in that it is not possible to detect
or predict from externally either the positlon of the virtual
lines and virtual surfaces or their changes. E~en information
previously obtained from prior experiences concerning the former
location of virtual lines or virtual surfaces are of no value
for any contemplated fooling of the space monitoring system, if,
as previously mentioned, the location or site parameters of
the virtual lines and~or virtual surfaces are chosen to vary as
a unction of time. -
- .
~ 78
If an object which has been detected by the measuring
beams moves, then hy mathematical processing of the measured
values or results, i.e. the transit times, as such are
represented by the distance vectors of the measuring beams, it
is possible to determine not only information concerning the
size and shape or configuration and position of the object, but
also movement criteria of the object. Such movement criteria
relate to the path of travel or trajectory of the object, its
speed and acceleration.
~0 In Figure 3 there is shown an exemplary embodiment
of equipment for measurement of a moving object 40 by means of
successive measuring beams 41. At the time t = to the object
40 is initially struck at position 40-0 by measuring beam 41-0.
It is possible to calculate the coordinates of the momentaxy
position of the object 40 which is hit by a measuring beam,
by means of the momentary distance of the object 40 to the erec-
tion site 2 of the directional beam emitter 100. These coordi-
nates can be computed based upon the transit time of the radiati
energy emitted from the directional beam emitter 100 to the
object 40 and back again to the receiver and the azimuth angle
and elevation angle~ which can be determined on the basis of -
the construction and mode of operation of the directional beam
transmitter for each point in time, especially for each in-
dividual one of the successive measuring beams.
~: ~
. I .
.,,.,., ~ - ~ ,
.,
, .
:
. .
~ 713 1
A vector Eo thus defines the position 40-0 ~7here
there is located the object 40 at the time to~
~ '
Analogously, a vector El, by virtue of its length
and its azimuth angle and elevation angle, defines the position
40-1 of the object 40 of the point in time tl.
Further, a vector E2 by virtue of its length,
azimuth angle and elevation angle defines ~he position 40-2 of
the object 40 at the time t2.
. - .
- The aforementioned vectors E , El, E2 are thus a
unction of the time and the angles~ and ~ .
. . . ..
Predicated upon the measuring beams or vectors,
i.e. the different positions 40-0, 40-1 and-40-2, tracking a
certain object, it is possible to thus mathematicaily obtain
information regarding the movement, i.e. the path o~ travel or I -
trajectory and~or the velocity and/or the acceleration as move-
ment criteria of the object 40. The required computation can be J
continuously performed in known manner by means of an electronic
computer.
~ ~ ~ - , ~
, ~ Based upon stored data there is also defined the
2 0 course of virtual lines, for instance the virtual llnes 17 and 18
. ~`ompa_e F ure 1l and suc~ ~an be lnfed =o the computer. It
- 19 -
~ ~ . ~
,.. ,,.,, .. ,.. ,, .,.. ,.. , . . . , . . . , . -
,
,: .
,
9978
should be apparent that with appropriate programming
of the electronic computer there can be timewise and
spatially calculated and indicated the passing of such
virtual lines 17 and 18 by an object 40 as the point of
intersection of the curve representative of the path of
travel of the object 40 with the virtual lines 17 or 18.
In anologous manner it is thus also possible with a
spatial arrangement, as shown in Figure 2, for the pene-
tration of vixtual surfaces 29 and 36 to represent the
boundaries of warning and protective areas, and by mathe-
matically evaluating a sequence of defined measur1ng beams
to also determine the entry of one or a number of objects
into such zones. Also the residence time of the measured
objects in such zones or spaces can be determined by
mathematical evaluation of the relevant measuring beams.
~ hile previously it was assumed that the object to be
measured was small in relation to the focal point, i.e.
the momentary cross-section of a beam or radiation bundle
belonging to a measuring beam, that is to say in the event
the object was stationary, it was not hit by two or more
successive measuring beams, it will be now assumed that
the object 40 to be measured is one having considerably
larger dimensions such that it is struck by a multiplicity
of measuring beams, the directions of which, in each
instance, are known.
- 20 -
'
.. ,
' '' , , ' , ' ' ' ,'
' , '
~129~7E~
By mathematical evaluation of such multiplicit~ of
measuring beams and the vectors resulting from the relevant
object 40, it is possible with appropriate programing of the
computer to not only compute criteria concerning ob,ect size,
shape, configuration, but also as concerns the movement behavior,
such as direction, velocity, acceleration, periodicity and so
forth. By comparison of such criteria or data with stored data
concerning size, shape, configuration, movement behavior, such
as direction, velocity, acceleration, periodicity, and so [orth
of known objects, it is possible, in the presence of at least
approximate data coincidence, to recognize the measured objects
and to identi~y the same and, for Lnstance, to allocate thereto
a certain object classification or category.
Generally, the method enables the determination of
all objects which move past a virtual line or penetrate a
vlrtual surface or are located in one of the partial surfaces
or partial spaces previously discussed.
, ., ~ , .
The diffexentiation between undesired or disturbing
objects and tolerable objects is dependent upon the local
: , æ o ~ resolution capability of the system, i.e. the method operations
and apparatus with respect tD such objeat and the extensiveness
of the program of the computer. Theoretically, one hundred
¦ ~percent iffere~LiatiD~ is p~ssible.
, .
~' - 21 -
~,
..........
: ', ' ' : -
, ~ , .
~Z9~7~
It is therefore also possible, accordiny to this
method, and with the apparatus to be still hereinafter described
in detail, by means of condition parameters of a monitored
surface or monitored space which have been infed by the
computer, to monitor such surface or such space both as concerns
conditions remaining the same and also with respect to any
condition changes thereof. Hence, it is also possible to eva-
luate changes which have been determined in accordance with
predetermined criteria by appropriately programing the computer,
1~ and to indicate the same and, if desired, to trip an alarm.
.'
It is here mentioned that the determination of the
aforementioned vectors and the different mentioned evaluations
and comparison of criteria with stored information constitute
computation operations which can be readily carried out by appro-
priately programing standard commercially available computers.
The nature of the program will be readily evident from the
function described herein, and there~ore need not be explained
more fully beyond the comments made herein, since computer
software does not constitute subject matter for which protection
2~ is solicited.
: ' '
~ Continuing, now Figure 4 is a side view, in schematic~
I ~ illustration, for explaining the height of virtual surfaces
~ with visibly shown focal points.
~ ~ ' ' I
~ , ~ - 22 -
. I
' ' . I
.. _.. ,, :
'-~ ~ ,.~ , - ,,,
' :
,
:-" l~Z9~7~3
The directional beam transmitter lO0 tansmits beam
or radiation pulses in a defined sequence as a function of time
in alternate directions. In the side view of Figure 4 there will
be recognized the terrain or surface l and the radiation beams
orbundles 42, 43 and 44, the respective momentary main beam or
ray of which has an elevation angle ~ 2 and~ 3, respectively.
In this example the first virtual surface 29 is assumed
to be a vertically extending surface. A second virtual surface
36 is likewise assumed to be a vertically extending surface, how-
ever having a smaller spacing from the directional beam trans-
mitter lO0. At the virtual surfaces 29 and 36 there are defined, ~ -
by means of the radiation beams 42, 43 and 44, the focal spots
45, 46 and 4~, 48, 49 respectively. These have been only
schematically indicated in Figure 4 by shaded ellipses, whose
dimensions are dependent upon the divergence of each radiation
beam and the distance from the directional beam transmitter lO0.
In the event that thé directional beam transmitter lO0 operates
with light pulses, then there can be employed a controllable
variable ocus lens or so-called vario-optic, whereby it is
possibls to control ths size o~ the focal spots aocording to
a program which has been infed ~o the computer, for instance-as
: a function of ~and/or ~ . ~
The~size of ths focal spots determines, among other
~things, also the~rsso1ution capability. To obtain an adsquate
~ ' ~:
,", ~ : : , .
23 -
-- - - . . .
,
:
monitoring security it is therefore advantageous to select tne
divergence of the radiation, the elevation angle ~ and the azi-
muth angle~ of the individual measuring beams and their sequence
as a function of time, in a manner such that there occur only
neglibible local and timewise gaps between the ~ocal spots.
The method can be performed both with a single dir-
ectional beam emitter, the radiation direction of which is
variable, and also with a number of directional beam emitters
which irradiate their radiation in different directions. The
different radiation directions can be accomplished, for in-
stance, either by providing a movable arrangement of the
transmitter itself or by providing movable radiation deflection
elements which are operatively associated with such transmitter.
. ' .
It is however possible to realize a directional
beam emitter in that, at least one transmitter ls arranged
following a beam splitter or divider system for the surface andJ
or spatial splittlng or fanning of the radiation or beam. With
such system there is then transmitted in different defined
directions, for instance pulsed electro-magnetic radiation,
especially light radiation, for instance infrared radiation,
in different defined directions, and the radiation reflected
at the objects or background is infed to at least one receiver
by means of one or a number of analogous radiation fanning
or splittlng systems and evaluated. The reflected radiation is
thus received preferably spatially selective.
, :
~ ~ 24
, :
.,
~ '. ' -, '
, - :, . - , :
; ', ' ................. .~ :
~2~97~ ~
If the energy transmission occurs in succession
as a function of time in different directions, then the cor-
responding reflected radiation portions are preferably likewise
received in succession and individually evaluated. Then there
is realized a transmission channel for the transmission of the
radiation and a receiver channel for the spatially selective
reception of the reflected radiation and for its further trans-
mission to the receiver. These channels are preferably decoupled
with respect to one another, in order to prevent spill-over of
transmitted radiation from the transmisslon channel directly
into the receiving channel. This is strived for in considera- ¦
tion of ~he large signal peak difference in both channels, so
that the receiver can be protected against over-cont~ol:
. . , , .
For particular applications, for instance
monitoring a number of discrete surfaces while using only one
transmitter and receiver, it is advantageous to transmit ra-
diation pulses according to a predetermined program in groups
ln different directions and to receive in groups reflections
in each case from the aforementioned directions and also to
~1~ 20 evaluate such received reflections in groups.
If radiation or beam pulses are transmitted in
groups in dîfferent directions and received in groups from
¦¦ such d ctions, then it is no= necessary to indivi~ually
.~ - 25 -
,, ~ . .
.
.,.. ,....... . -
- ,:
,
- ~ .
.~ ' . .
~2~B
evaluate each signal from each direction. If, namely, there
occurs in the radiation splitting region, for instance due to
~, ' an intruding o~ject, a change in the reflection properties, i.e.
reflection of at least one of the split or fanned beams to a
different location than before, then also with common evaluation
of an entire group of signals there occurs in the thus obtained
summation signal a change. This change of the summation signal,
in relation to the undisturbed condition, can be beneficially
employed as the criterion for alarm tripping.
~0 If there are employed at least two radiation or
beam splitting systemsj each with a surface-like fanning of the
radiation in different surfaces, in other words staggered spatial-
ly, then an object moving through at least two surfaces causes
timewise staggered changes of the received signals. Consequently,
by evaluating the timeWise difference and the se~uence of the
change of the output signal in the at least two systems, it is
possible to determine the directlon of movement of an^intruding
object and such can~be employed as a further criterion for the
directional-dependent alarm tripping or triggering.
. ', .
0 Basically, the method can be used with all energy
which is irradiated as pulses, for lnstance ultrasonic energy,
~especially however also eletromagnetlc energy. There is prefer-
ably suitable pulse-shaped laser radiatlon and especially in the
region of invisible ilght~ ~for lnstance in the infrared region.
'
",, ,
- 26 -
,
,
:
. . . ::
13L2~7 53
According to a given field of application it can be
advantageous for the purpose of as gapless a covering as
possible of a virtual surface with focal spots, that the
focusing of the radiation is controlled as a function of
the momentary direction.
In consideration of controlling the dynamics of the
receiver system i.e., the faultless processing of both
very weak and also very strong signa]s, it also can be
advantageous in certain situations to control the trans- ~
mission output and/or the receiver sensitivity as a
function of the radiation direction.
However, it is also possible for this purpose to con-
trol the transmission output and/or the receiving sensitiv-
ity as a function of the magnitude of the measuring beams
or the distance vectors and/or the intensity of the
reflection.
The method also can be designed such, according to ~-
further aspects thereof, that not only are there evaluated
the distance vectors, but also~ the intensity of the radia-
tion reflected to the receiver. For instance, in this
manner it is possible to detect certain objects based upon
; ~ their greater reflection capability in contrast to other
objects and/or in contrast to the background. Their
related measuring data, obtained from their distance
25~ vectors, can be specially processed or evaluated, based
upon the additional evaluation of the higher
7~-
:
~- ,,~,
, "', "'' ' ~ :
; ~29~8
intensity of the reflected radiation infed to the receiver. It
is also possible to obtain an appreciable data reduction if .
the computer and the storage only have inputted thereto such
selection of data which, based upon the greater intensity of
the reflection, is at least periodically of particular interest.
The evaluation of the received vectors thus is
limited, for instance, as concerns site of the reflection and/or
movement behavior of the relevant ob]eGt, only to a desired
number of objects.
. ..
This selection can be accomplished, for instance,
by the arran~ement of a conventional threshold value device
in the receiving channel.and/or by an intentional, at least
periodic, reduction of the transmission output of the directional
beam emitter and~or the receiver sensitivity in relation to
normal operation.
: .,
: It is also possible for the determination of
: certain points at the terrain or space, for instance selected
points of vlrtual li.nes and/or virtual surfaces which axe to
be fixed, to periodically arrange at the relevant locations
of the terrain or space highly reflecting objects, ln particular
for instance, so-called retro-reflectors,.to then measure
:~ at such the reflected radiation or energy in the manner hereto-
:
.
: - 28.-
. :
. :~ ' .
' '
; : .
llZ9978 1-
fore described and to store the thus obtained coordinates of
the erection site of these particularly strongly reflecting
2 objects i.e. retro-reflectors for the purpose of determining
the virtual lines and~or virtual surfaces.
It is also possible to employ the method in
conjunction with traffic monitoring. For instance, a virtual
line or virtual surface can be fixed transversely with respect
to a traffic lane, and there can be determined passing through
or penetration of such virtual line or virtual surface, and the
10 relevant data evaluated and for instance counted or recorded.
. ..- , ~
. The method also can be employed for many different
fields of application as concerns traffic monitoring; thus for
counting traffic, evaluating traffic conditions, for instance
traffic jams on highways or freeways, controlling traffic regu-
lation installations,;controlling parking garages, monitoring
vehlcles where the driver has violated a traffic signal, for
instance crossed a red light and;so fcrth. ~
~ : .
~Generally speaking, it can be stated that the
; ~ method for monltoring a surface or space is suitable both for
ao constant and changing conditions, wherein both the fact that
~;the~condition remains~constant and also the fact that the
condition changes can be beneficially evaluated and/or indicated.
29 ~
~ ' .
~29978
Thus, there can be monitored, continuously or periodically
as to its condition, for instance, as the object a terrain
slope or face of a mountain which is prone to the danger
of an earth slide, a structure such as for instance a dam
wall or a dam, a bridge and so forth. If there arise
impermissible changes, these can be detected, recorded or
reported by sounding an alarm.
In order to solve these special functions it is advant-
ageous to fix a virtual line or virtual surface so as to
lie at least approximately at the surface of the monitored
object, for instance a structure. Changes then have the
effect that, for instance, at least part of the surface of
the monitored object or structure penetrates into another
partial surface or another partial space. This is indica-
ted by an appropriate output signal of the computer, so
that, if desired, an alarm can be triggered.
Continuing, by referring to Figure 5 there is shown
therein, in sectional view, a first exemplary embodiment
of a directional beam emitter. In such Figure 5 reference
character 100 designates the directional beam emitter in
its entirety, in other words, it encompasses not only
the transmitting section but also the receiving section
together with the related auxiliary devices.
- 30 -
~ '
'
: , ,
,
- .
~' " ' , ' ' ' :
~ 19~29~378
The directional beam emitter 100 will be seen to
comprise a lower portion 101 which is attached at the erection
, site or location 2 (F.igures 1, 2 and 3). At the lower section
. or portion 101 there is rotatably mounted, by means of a needle
bearing arrangement 102 or equivalent structure, an upper
portion or section 103 for rotation abou-t a stationary shaft
or axle 104.
A drive device or drive 105, arranged at the lower
portion 101, drives, by means of a hollow shaft 106 and a
10 coupling not particularly shown in Figure 5, the upper por-
. tion or section 103. This upper portion or section 103 is
rotated, for instance, at twelve revolutions per second about
the fixed shaft 104.
. .
An e~ample of a rotational transmitter 101 will
be seen to comprise, on the other hand, a rotational trans-
: mitter disk 108 r.igidly connected by means of the shaft or
... , .
; ~ axle~104 with the lower portion 101, and which transmitter
: disk 108 is stationary in relation to the lower portion 101,
: and, on the other hand, further contains sensors 110 connected
: ~ 20 with the hous~ing lO9 of the rotational transmitter 107, ashas been~merely schematically indlcated in Figure 5. Since
the houslng 109 of the rotational transmitter 107 is rigidly
connected with the upper por:tion or section 103 of the.
. ~ directional beam emitter lOl, lt rotates together with the
~ ' ~:::
~ - 31 -
.,,
.
. :
' `
,
~ 78
sensors 110 abou-t the shaft or axle 104, and thus, moves re-
lative to the lower portion or section 101 and the therewith
rigidly connected rotational transmitter disk 108.
By means of the rotational transmitter 107 and its
sensors 110 it is therefore possible to infeed to a computer,
at any moment in time, the instantaneous relative rotational
position of the upper portion 103 as a measurement value emana-
ting from the sensors 110, by means of the lines connected
with slip rings 111.
,.,' ' .
In the rotatable upper section or portion 103 there
are mounted-further components necessary for the operation of
the directional beam emitter 100. A pulse transmitter 112, for
instance a laser diode transmitter for the outfeed of pulsed
infrared radiation, the latter beiny designated in Figure 5
by a diverging transmitted light beam 113, transmits such
radiation by means of a first optical system 114, for instance
a parabolic mirror, in the form of a substantially cylindrical
paralle; ray-radiation beam or bundle 115, of essentially
circular cross-section and extending horizontally until the
; ~ image beams, towards a movable beam deflection element 11~, for
instance towards the lower side of an oscillating mirxor 116
wh1ch is eflectively coa~ed at both sides or ~aces.
. - 32 -
~' , .`
,
.'
,, , :
,.. :. "' ; ~ ~ ' ,.' ~
-~ ~9~7~
The beam deflection element 116 is pivotable about
a shaft 117, inclined with respect to the horizontal through
, 45, as a function of time through e~actly defined angular
values in the sense of thé double-headed arrow 118. For pivoting
of the beaM deflection element 118 the same is provided with a
suitable pivot mechanism or device ll9 which is rigidly secured
at the upper portion 103. In order to reduce the moment of
inertia of the movable beam deflection element 116 it is also
advantageous to impart to the oscillating mirror 116 an eLlip-
~0 tical configuration or shape, wherein the major axis extends
in the direction of the axis 117 and the minor axis transversely
thereto in the plane of the oscillating mirror 116. These
measures facilitate the attainment of high deflection frequencies.
The parallel ray beam 115 is thrown or reflected
by the radiation deflection element 116, in the p~esent case
by the underside of the oscillatlng mirror 116, downwardly onto
a deflection mirror 120. This deflection mirror 120 is in-
clined with respect to the horizontal through an angle of about
45 , and constitutes a second optical means which is ri~idly
~0 connected with the upper portion 103. The deflection mirror
120 has a surface which is turned by 90 in relation to the null
positlon of the surface o~ the beam deflection element 116, i.e.
the oscillating mirror. The deflection mirror 120 propels
the light which is infed thereto by the beam deflection element
116 in horizontal dixection, in other words perpendicular to
~:
~,
, - 33 -
: '
.
: : :
~Z9~7~
the plane of the drawing of Figure 5, in the form o~ a measuri~y
beam towards the front; in Figure 5 such has been shown as a
small circle having a center located at the deflection mirror
120. The measuring beam departs to the outside by means of a -
standard window provided at the upper portion 103 and not
particularly shown in Figure 5. If the beam deflection element
116 oscillates, as described, then the beam.which is forwardly
deflected by the deflection mirror 120 rocks or pivots relative
to the upper portion 103 of the directional beam emitter 100 in
a vertical plane. Since now, however, as described, the upper
portion 103 and thus also the first optical means, in other
words.the parabolic mirror 114, the beam deflection element 116
and the second optical means, here the deflection mirror 120,
co-rotate alon~ with the UpFer portion 103, the aforementioned ver-
tical plane rotates the transmitted light, emanating from the
upper portion through a window thereof, likewise about the
shaft 104. Hence, by kno~ledge of the point in time of the
transmittéd light pulse and the related rotational position of
the upper portion 103, it is therefore possible to exactly define
the momentary azimuth angle~ and by means of the momentary pivo-
tal position of the osclllating mirror of the osci1lating def-
lection element 116 it is possible to exactly define the
momentary elevatlon angle~ o~ each individual measuring beam
o the directional beam emi~ter 100. ~ -
: :
: :' ,
~ ~ :- 34
~':'''' . .
~ :; .
.. . ~, , . ~ - i. . . .
.
,
,
.
~'s~, ' ' " , , , ': . '
,
:. - : : - . ,
~ 99~
There also can be used as the first optical means 114,
instead of the parabolic mirror, a so-called vario-optical
means or variable focus lens having a deflection mirror, enabling
a controlled variation of the focusing of the transmitted
light beam 113, and thus, also the outwardl~ propogated measur-
ing beam.
The light of the measuring beam whlch has been reflected
at the outside arrives by means of a further window of the
upper portion 103, which window has not been particularly shown
1~ in Figure 5, at a second deflection mirror or reflector 121
which is inclined with respect to the horizontal. In Figure
5 the receïved light bundle or beam has been shown at the
deflection mirror 121 in the form of a circle having a cross.
From the second deflection mirror 121, the received light bundle
or beam arrives perpendicular downwardly at the upper side or
face of the beam deflection element 116, here the oscillating
mirror, which, as will be recalled, is reflectively coated at
both sides or faces, and from that location, b~ means of a
further parabolic mirror 122, in the form of a converging
~ received radiation beam 123, at a receiver 125. The further
parabolic mirror 122 preferably coacts with a narrow-band inter-
ference filter 124 for suppressing the effects of foreign or
spurious light. The recelver 125 converts the received radiation
into olectrical signals or pulses which are processed by a
- 35 -
,, . .
' . . .
-: ., . " - :
~ ' ~
.. . .
.
~ 9978
computer, as will be explained shortly.
., ~ Mounted at the directional beam emitter 100, for
instance at the upper portion 103, are also the related auxiliary
devices which are normally needed, such as current or power
supply elements, control and regulation devices for the drive
105 and the pivot device 119 as well as the components of the
computer. This has been illustrated in Figure 5 by a series of
symbolically shown electronic plug cards 126.
. , .
By means of the lines or conductors 127 the direc-
tional beam emitter 100 is powered with electrical energy, for
. lnstance from an alternating-current power supply network or
from a battery or other suitable power supply. By means of
further lines or conductors 128 the directional b~am emitter
100 delivers the output signals whichhave been processed thereby,
for instance in a coded form. These output signals can be utili-
zed in conventional manner, for instance, as condition reports
and/or alarm reports for display or indication purposes.
~ ; ~ '
It is here i~rther still~to be mentioned that the
measuring beams~41 (Figures~2 and 3j or 42, 43, 44 (Figure 4),
delivered by the dlrectional beam emitter 100 in accordance with
the pulse~train-frequency of the pulse transmitter 112, produce
focal spots 45, 46, 47, 48, 49 (Figure 4) at the region of
-he virtual lines or virtual~surfaces 29, 36 (Pigure 3). In
' ' ~
, ~ 36 -
,; ~ .,
.
' ,. ~ , . . '.. :, . . . . - ! ,
.. ,, , ' ~ ' ' ' .
-~ ~2~7~3
this respect it is advantageous, on the one hand, to select
or control the size of such focal spots and, on the other hand,
the pulse repetition frequency of the pulse transmitter 112
such that such focal spots are produced in succession and in
successive circumferential regions, accomplished by the
rotation of the directional beam emitter 100, and by the vary-
ing vertical deflection of the measuring beams, accomplished
by the beam deflection element 116, there is possible covering
of the selected virtual surfaces as free of gaps as possible
When using a light transmitter, also infrared light, as the
pulse transmitter 112, it is advantageous to regulate the size
of the focal spots, by means of a regulation and control unit
operatively associated therewith, for instance along the first
virtual surface as a function of their momentary distance from
the directional beam emitter 100
Figure 6 is a block circuit diagram of an exemplary
embodiment of apparatus for he performance of the inventive
method The pulse transmitter 112 transmits laser pulses in
the infrared region, thè pulse repetition frequency of which
is controlled by a~re~ulat~lng and control unit 130 by means of
a line or conductor 131 The transmission pulses of the pulse
transmitter 112 pàss through a varlable focus lens or vario-
optic system 132, the focuslng of which ls controlled by the
regulatlon and control device 130 by means of a control line
133 The transmission pulses are th~n deflected by the beam
.
i - 37 -
~ . ~
: :' ,' ~ : '
: '
'
- . .
~L29~77~
deflection element 116 in accordance ~ith its momentary
position and infed to the deflection mirror 120. The
deflection mirror 120 deflects the transmission pulses, as
a measuring beam 40, in a direction defined by azimuth ~
and elevation ~ in accordance with the momentary rotational
position of the directional beam emitter 100 and the momen-
tary pivotal position of the beam deflection element 116.
The resultant transmitted light beam is focused in accor-
dance with the momentary setting of the vario-optic system
132
Based upon the data infed to the regulation and
control device 130 by the rotational transmitter 107 by
means of a line 134 and by the beam deflection element
116 by means of a line 136 and also the data infed from
a central computer 200 which is received from a line or
conductor 136*, the regulation and control device 130
controls the correct position of the beam deflection
element 116 in order to direct the measuring beam ~0
exactly in a defined direction ~, ~. To improve such
control operation a line or conductor 135 leading to the
control and regulation device 130 delivers data regarding :.
the actual position of such beam deflection element. The
central computer 200 is a commercially available computer,
such as Single Board Computer iSBC 86/12 of Intel
Corporation, Santa Clara, California.
The received light 40* reflected by the background of `-
the monitored terrain 1 (Figure 1) or space 22 (Figure 2)
.
- 38 -
: . ,~-~i.
.~ ,....
: ... .
.-:.. , .,.,, .. , .. - . . . . . .
: ~ .
.. . .
.
.
-
-
.: ~
~299q~
or from an object 40 (Figures 2 and 3) arrives, by means of
the second deflection mirror 121, the beam deflection element
116 and the further parabolic mirror 122, through thé narrow-
band interference filter 124 at the receiver 125. By virtue
of the selected construction of the directional beam emitter
100, the same has been disclosed by way of example with reference
to Figure 5, there is insùred that the receiver equipment con-
taining the components 121j 116, 122, 124 and 125 always is
aligned exactly in the opposite directio~ than the transmitted
measuring beam 40.
Now in order to be able to perform the method
of the invention by means of the directional beam emitter 100
the latter contains a computer 400 composed of the mentioned
central computer 200 and a satellite computer 300 and a group
of auxiliary devices 500 operatively associated with the com-
puter 400. The satellite computer is likewise a commercially
available computer, such as Single Board Co~puter iSBC 8/20
of Intel Corporation. ~
~ ' ` ~ : ' .
The central computer 200 comprises a first input/
~:~ 2~D output unit (I~O-port) 201 and a second Lnput/output unit (I~O-
; ~ port) 202, and, addltionally, a central processor unit (CPU)
203, a programmable storage or memory (PROM) 204, a first read-
write memory with r~andom access (RAM) 205, and a second write-
~ read memory witl random access (R~ 206. All of these componentc
; ~ : ~ :
~ ; _,39 _
'; ~
:, ~ , ,
,, - ,
1 ~ : ': ` , :
-~ ~L2~97~
are connected in known manner with one anothex by means of a
first multiple-bus (BUS) 207 or can be brought into operative
connection with one another.
The satellite computer 300 comprises an input/output
unit (I/O-port) 301, furthermore a central processor unit (CPU)
302, a programmable storage or memory (PROM) 303 and a write-
read storage with random access (RAM) 304. Here also, all of
these components can be interconnected or brought into operable
interconnection with one another in conventional manner by
1~ means of a second multiple-bus (BUS) 305.
:,--- , . . .
The central computer 200 and its multiple-bus 207
and the satellite computer 300 and its multiple-bus 305 have
operatively associated therewith a common bus-control unit
401.
' : . . -
~ Between the first multiple-bus 207 o~ the central
aomputer 200 and the secon~ multLple-bus 305 of the satellite
computer 300 there is arranged a transmitter-receiver unit
(transceiver) 402 for data traffLc between both of the buses
207 and 305 and between the central computer 200 and the satel-
lite computer~300. ~
~ , ~:
: : The followlng auxiliary devices are operatively
correlated wLth the compuoer 400: a real tLme clock 403, which is
: '
:: ~ ~' : ,. I
~ : : : - 40
~ ~ ' ~ '.
,,. :,: , ... .
~ ~LZ~78
provided both as the time or frequency base for the rotational
, transmitter 107 and the control and regulation unit 130 and
also for the control of the aforementioned computer 400. There
are also provided the current supply components 404 with the
associated control unit 405, an input unit 406 both for turning-
on and turning-off the directional beam emitter 100 and also
for the selection o the desired operating state. By means
of this input unit 406 there also is accomplished the switching-¦
on of the drive device 105. As a further auxiliary device
there is provided an output unit ~07, for the output of the data
obtained by means of the directional beam emitter 100, thus for
instance condition reports regarding the monitored terrain or
space, determination or reporting certain changes, coordinates
and further inormation or data with respect to detected ob-
jects, alarm signals and so forth. Such data can preferably
be delivered by coded signals which are suitable for use in
known indicator devices and/or alarm devices.
. .
At thls point there will be considered the mode
of operation o~ the described equipment based upon the il-
i 20 lustration of Figures S and 6 and the further Figures 7 and
8 or a predetermined field of application.
Pigure 7 shows a sahematic elevational view of the
measuring beam course during the fixing of certain virtual
surfaces. This elevational view illustrates the conditions
, . : .
~ ~ ~ '
~ - 41 -
~,,. ., ~, ' ,
:
~ . ' /~,, .
9978
in a vertical plane having the azimuth ~1 through the axis of the
~ directional beam emitter 100, wherei~ for the initial input of
-.~ coordinates of a first virtual surface.I there is periodically
arranged a retro-reflector 501 at the height h. A measuring
. beam 502 impinges the retro-re~lector 501 and has an elevation
. angle ~1~ The distance between the directional beam emitter
100 an~ the retro-reflector 501 in the irst virtual surface I,
in the direction of the measuring beam 502, amounts to Eo. If
there is again removed the retro-re1ector 501, then a measuring
a beam in the mentioned vertical plane and at the elevation angle
1 can impinge the terrain 1. This produces, until the im-
pact point 503, a distance vector which is longer by the value
Eo, wherein Eo + ~E = El.
. . . .'
A second virtual surface II is now fixed by the
impact point 503. In the same vertical plane where there ex-
tended the measuring beam 502, it is now possible to transmit
with an elevation angle difference~l a further me~suring beam
504. This further measuring beam 504 strikes the terrain 1 at
the further impact point 505.~ By means of this further impact
point 505 there is now also fixed the;position of a thlrd virtual
surface III. As best seen by referring to~F~gure 7, there is
valid the relationship E2 = El ~ El. In analogous manner there
is formed an impact~point 507 at the terrain 1 by a higher trave-
:
ling measuring beam 506 whLch travels at the greater elevation
, ~ ~ ; ' , , .
~ ., - 42
~ .
", ' ' '" '
.
'
angle difference ~ ~ 2~ and by means of which there is fixed a
., fourth virtual surface IV. Also in this case there is valid, in
analogous manner, the distance vector E3 = E2 +~ E2.
It is to be observed that due to th~ elevational
angle difference ~1 and ~2 the distance differencel\ El and
E2 between the second and third as well as be-tween the third
and fourth virtual surfaces is fixed~. Additionally, by virtue
of the height h and the difference~ Eo and the elevation angle
~ 1 there is determined the horizontal spacing A o the second
1~ virtual surface II from the first virtual surface I or the retro-
reflector 501.
. In the case under consideration it has been assumed
. that the virtual surfaces I, II, III and IV extend vertically. If
the.virtual surfaces are selected to be spherical, with the
directional beam emitter 100 as the center, then there are rea-
lized simplifications in the computations, since the ~istance
vectors of all points of one such surface are equal.
. ~ . '
Figure 8 shows a schematic plan view of the course
: of measuring beams during the fi~ing of certain virtual surfaces.
;~ The measuring beams emitted at the azimuth angle ~ 2~ ~3 and
: . ~4 and in each case at the elevation angle~ 1 +~1 and
: : ~ +~YI + ~ 2 by the directional beam emitter 100 ~mpinge, on
~: .. ' . .
. - 43 -
'~'
' .
.. . .
.
~ 3~29978
the one hand, the retro-reflectors 501, 508, 509 and 510 which
are periodically erected at the terrain 1, and, on the other
hand, when they extend at the azimuth ~ 1 corresponding to the
vertical plane, they impinge the impact points 503, 505 and 507
. at the terrain 1. However, if the measuring beams travel in
the vertical plane in accordance with the azimuth ~2' then,
depending upon their elevation angle, they strike the impact
points 511, 512 and 513. If the measuring beams extend in the
vertical plane in accordance with the azimuth ~3, then, depending
10 upon their elevation angle, they strike the terrain 1 at the --:
impact points 514, 515 and 516. Finally, if the measuring
beams extend ln the vertical plane in accordance with the azimuth
, then, depending upon their respective elevation angle, they
strike the impact points 517, 518 and 519.
. ' . ~'
The impact points 503, Sll, 514 and 517 thus
determine a virtual line 520 in the terrain 1, which constitutes
the projection of the virtual surface II which, in this case, :
has been assumed to be vertical. In the same manner the impact
points 505, 512, 515 and 518 determine a further virtual line
2~ 521 in the terrain 1, which constltutes the projection of the
further virtual surface III. which, in this aase, has been like-
~ wise assumed to be vertical.. Finall~,:the impact points 507,
: ;~ 513, 516 and 519 determine an additional virtual line 522 in
the terrain 1, which constltutes the projection of the additional
virtual surface IV, here again assumed to be vertical.
::
'
~ - 4~ -
,. ' : - : , ,
,
.... .. .. . .
~2~978
It therefore should be apparent that by virtue of the
periodic arrangement of retro-reflectors it is possible to
determine, in a simple manner, by means of the directional
beam emitter 100 the coordinate values needed for the
fixing of the virtual lines 503, 505, 507 (Figures 7 and
8) and for the fixing of the virtual surface I, II, III,
IV (Figures 7 and 8). By appropriately programing the
central computer 200, shown in Figure 6, it is possible to
store and evaluate the thus determined coordinate values.
However, it is also possible to freely fix or
determine a first virtual line 523 in the terrain 1 as the
starting basis for the determination or fixation of the
virtual lines and virtual surfaces and starting from such
virtual line 523 to ix further virtual lines in freely
selected fixed spacings. The thus resultant coordinate
values can then, ~or instance, be infed manually by means
of the input unit 301 of the computer 300. Depending upon
the topographical conditions of a field of application the
first or the second mentioned method may be more advant-
ageous ~or the determination of the virtual lines and
surfaces.
Preferably, the line 523 also can be assumed to be
equidistant to a virtual line 520 which has been deter-
mined previously by means of retro-reflectors 501, 508,
50g, 510 and the impact points 503, 511, 514, 517. This
line 523 preferably
- 45 -
''''`'' ,':' ~ ., ' ' '. ' ' '
: . . . . . ..
. . -
~ llZ9978
can be be assumed to be at a spacing from the virtual line 520
which constitutes the minimum below the spacing of the retro-
, reflectors 501, 508, 509, 510 to the related impact points 503,
511, 514, 517. This procedure simplifies the computation or ¦ -
mathematical operations to be performed by the computer 400.
The mode of operation of an apparatus according to
the préviously described exemplary embodiment is as follows:
By means of the input unit 406 the equipment is placed
into operation. The input unit 406 assumes a number of func-
tions and initiates different measures, and specifïcally:
1. Turning-on the current supply section 404 and the drive
device 105.
2. Determination of the spacing between two virtual surfaces.
3. Plotting (once) the coordinates of a virtual surface.
4. Normal operation.
5. Turning-off the equipment.
1.1 During the turning-on of the current supply
section 404 and the drive device 105 there is
simultaneou~ly placed in~a~defined starting state
2 0 the central computer 200 and the satellite computer
; ~
. ~ ~ ~ ~ 46 -
':, . ~ ~ .
:
I ~ ' , I
~',, ' . ' ' ' ' ~ ' :. '
'',"' ''~' ' ', .-'"
~'' ; ' ~ " ' ' '. :
~ 78
2.1 The determinatiOn Qf the spacing between both of
the virtual surfaces can subsequently be accomplished
manually accordiny to rubric 1.1 above. Then in
the first write-read storage (RAM) 205 of the central
computer 200 there are introduced the constants, in
order to distinguish between the virtual surfaces.
Thus, for instance, three virtual surfaces are linked
by two constant angles.
.
3.1. A further command, "plotting a virtual surface",
infed to the input unit 406, activates the program
which is stored for this purpose in-the program storage
(PROM) 204 of the central computer 200. The satellite
computer 300 remains in its starting state. The
equipment now accomplishes the following working steps:
3.1.1 Recei~er 125 is set to the lowest sensitivity
stage.
. .,, ' ' ' .
3.1.2 The entire space detected by the d1rectional
beam emitter 100 is scanned without~any gaps
- by the measuring beams, that 1s to say, through-
out the entire azimuth and elevation range.
. .:
3.1.3 The scanning lines pass with maximum focal
spots. ~
~ ~ ,
~: .
~ 47 -
.~ . -, .
.~ .
~2~
- 3.1.4 Recording and storing characteristics values of
selected sites which, by virtue of increased
reElection capability, for instance, by using
a retro-reflector which is -temporarily located
thereat, produce an increased intensity of
the received light. Termination of the first
recordal or plotting phasel
3.1.5 Mathematical linking by linear interpolation
as aforedescribed of the values (coordinates
obtained under rubric 3.1.4. into a function E
(y,~). This function is now specific to the
equipment as concerns a defined task and the
erection site of the directional beam emitter.
The function E(Y,~) is stored in the first write-
read storage (PROM) 204 of the central computer
200 and remains unchanged throughout the entire
time of employment of the equipment.
3.1.6 Transmission of the function values E(Y,~) from
the central computer 200 to the control and
regulation device 130 together with the constant
angle ~ ~ for the spacing of the virtual surfaces
(see the previous~rubric~2.1) for controlling
- the beam deflection element 116. Additionally,
a constant
- 48 -
::
: -~ - --- - :
,
~ .
~2~
pulse frequency (pulse transmitter 112) is
infed to the control and regulation device 130.
, ' ~
3.1.7 Start of the second recordal phase for genera-
ting the actual-values of the distances for
the individually provided virtual surfaces.
There are derived from the actual-values for
the virtual surface II (Figure 8), by sub- -
traction of the value A (Figure 7), the re-
lated reference values for the virtual surface
1~ I (Figures 7 and 8).
These values are stored in the first write-
. read storage (RAM) 205 of the central computer
200 and remain constant throughout the entire
time of employment of the equipment.
The distance actual-value for the outer ~irtual
surfaces III, rv (Flgures 7 and 8) are cal-
culated fromthe corresponding actual-values
of the next lnner vlrtual surfaces.
The resultant dLfference value~ E together
;~ ~ with the distance aGtual-values as the actual
function is stored in the first write-read
storage~(RAM~ 205 of the central computer 200
and constitute the reference values for a
scanning cycle. ~The storage of 11 reference
,, ~ 9_
,
. .
.
~ 978
values in the first write-read storage 205
occurs in a timewise order.
~ ' ~ .
3.1.8 Clearing of the existing characteristic values
which hay~ been carried out in accordance with
rubric 3.1.4 above.
4.1. After the equipment has processed the reference
values in the afore-described manner, it is then
capable of assuming and performing the normal opera-
tion for the monitoring or supervision ~ith the
1~ program ln the program storage 204 of the central
computer 200 and the program in the program storage
303 of the satellite computer 300. This normally
occurs by means of a control command which i5 de-
livered by thé input unit 406 to the central computer
200 and the satellite computer 300. `
The program stored in the program storage (PROM) 204
is developed for the specific fleld of use of the
equipment. In`the case of the central computer 200
it contains, apart from the method steps for recording
the virtual suraces,the steps for storage of the
infed distance~measuring values, their comparison
with stored~reerence values for obtaining diferences
which are o be stored aAd for the output of stored
. .
~ ~ 50 - ~
'' : ~;
978
reference values for defined angular values in the
sense of the double-headed arrow 118 of the beam
deflection element 116 (Figure 5) and for input to the
regulation and control device 130 (Figure 6).
In the assumed examplary embodiment the switching
from the previously mentioned measure (step) 3 to the
measure (step) 4 occurs automatically after fulfilling
the measures (steps) l to 3 and determining the mode
of operation (vertical or horizontal orientation of
the rotational axis of the directional beam emitter
100~, something requiring different programs for
processing of measured values.
Due to the coacting of the computer 400 with the
directional beam emitter and owing to the controlled
rotational movement of the directional beam emitter
100 and the controlled pivotal movement of the beam
deflection element 116 the equipment performs the
function E (~,~), and specifically, a number of times,
depending upon the number o virtual surfaces,
: - 51 -
'.
~ '
.. , ~ , ~ ~ . .
, ~ .
. , ~ .
': .' , ' ' "`' " ": ': ' ,
,
12~
Since the directional beam emitter 100 only rotates
with approximately constant angular velocity, but the
angular scanning must be accomplished with maximum
accuracy, the outfeed of the radiation pulses of the
pulse transmitter 112 (Figures 5 and 6) must be con-
trolled with the air of the instantaneous values
of the rotational trasnmitter 107, by means of the
regulation and control device 130, in such a manner
that the pulse frequency, while no longer a constant
frequency, however, delivers the individual pulses ~-
in all instances in the angular position correlated
therewith. The corrections needed for this purpose are
undertaken by the regulation and control device 130
based upon the data ~,'Y or E~ ) stored in the write-
read storages 205 and 206 of the central computer 200.
From each received pulse obtained by reflection there
is formed a distance actual-value and stored on-line
in the write-read storage 205 (Figure 5), that is to
say in-step. Thereafter, the distance reference-value
which has been stored in the write-read storage 205,
possessing the same azimuth ~, but corresponding to
an inner virtual surface, i.e. the elevation,~O, is
subtracted from the distance actual-value. The
- 52 -
~, .
, ., -, ~ ~
:
.
~LZ~g71~
resultant actual-difference~ E = f (J,~) is now
compared with the reference-difference stored in
the write-read storage 205. For t'ne case that the
reference-actual value difference is not equal to
null, then the actual-value difference is stored as
the new reference-value difference in the write-read
storage 205 and furthermore also in the write-read
storage 206.
The reference-value distances in the write-read
storage 205 for the virtual surfaces -- with the
exception of those with the virtual surfaces I
(Figures 7) -- are likewise replaced by the actual-
value distances, and thus form the reference values
for the next scanning cycle.
Normally, with unchanged periphery the reference-
actual value difference is equal or substantially
equal to null, that is to say, there are not s~ored
any new values.
As soon as an object enters the periphery or the
virtual surface, then this difference becomes greater
than null, and thus, is stored in the described
manner in the write-read storages 205 and 206.
- 53 -
', ' ' ' '~
.
- '' ' ' ~
~ ~9~
The satellite computer 300 (Fiyure 6) avails it-
self by means of the collecting bus-control unit
, 401, via the transmitter/receiver 402, of the
timewise and locally coded differences~ E = f
(~,~), under circumstances also the function E
(~ ) from the write-read storage 206 of the
central computer 200 and stores such in the write-
read storage 304.
Of course the central computer 200 possesses prio-
i 10 rity, so that the satellite computer 300 can only
- then interrogate data when the central computer
200 pauses. -
In the program storage 303 of the satellite
computer 300 there are contained the criteria for
elimination of false alarms by inconsequential
influences, as well as for se1f-checking of the
equipment. Under ~he term "inconseguentlal
influences9' there are~ to be understood those
brought about, for instance, by birds, leaves,
- snow, small moving animals, balls and light. On
the other hand, appreciable in1uences or factors
are Eor instance, intruders.
. , ~' ~ ' , .
- The satelllte computer 300 possesses, by means
of its own input/output unit 301, a connection
.
.
~ - 54 -
.
. . ,, ~ ,
; ' , ' " '
~ ' ',. :
~ 7B
to the output unit 407 and to the real time clock
403. It assumes the task of checking the
electrical-mechanical state of the equipment by
means of the corresponding control lines. The
differences which are processed in accordance
with local and timewise correlations, depending
upon the comparison criteria, trigger a pre-alarm
or aLarm from the program storage (PROM) 303,
which is then further transmitted by the satellite
~0 computer 300 to the output unit 407.
All of the differences which have been stored
by the satellite computer 300 in its write-read
storage (RAM) 304, after expiration of a certain
amount of time derived from the real time clock
403, are cleared after the input of the last
difference considered ~ith respect of time. This
operation repeats periodically after expiration
- of such period of time.
. .
Due to the selected ma~ner o~ data processing in
2~ the central computer 200 together with the last-
mentioned measures in the satellite computer 300
it is possible that, for instance~ with an ar-
rangemént of the directional beam emitter 100
upon a building and monitoring of the surroundings
~ ' : . , .
- - 55 -
, :
. .
-- . - . -
, ; , .. ..
. ~ ' ,~ . ' ,
- , . ~ .
~299~
.
The equipment reacts equally, by not sounding an
alarm, to buildings which are erected at the working
region of the directional beam emitter, as well as
to a growing blanket o~ snow. The latter will be
detected in that the distance between the outer
virtual surfaces remains constant, but the difference
between the virtual surfaces I and II (Figures 7 and
8) varies. In the presence of fog the differences
of the outer virtual surfaces alter proportionally as
a function of time or in succession, those of the
innermost virtual surfaces last. Birds and loose
leaves, which have not tripped any alarm, are
eliminated in that the (last) difference beween the
last and the next to last virtual surface co, and the
next to last difference remains unchanged. Since the
satellite computer 300 always immediately interrogates
the differences from the write-read storage 206 and
thus clears; this write-read storage 206 can be
designed as a small storage unit or memory.
Apart from the storage of distance measuring values
and the comparison with reference values resulting
from the differences, which are like-wise stored, the
central computer 200 also has assigned to it the task
of making available to
~ - 56 -
,:~
` . ,, ' ,,,
, . ~': ,
.:
-. ~ 97~3 1
the regulation and control device 130 the value
which follows the occurring distance measured
value in respect to angular data, related to
its resolution tlme, for the rotational trans-
mitter 107 and the beam deflection element 116.
The regulation and control device 130 determines,
by means of the values from the rotational
transmitter 107, in the regulation loop, the
. time during which the beam deflection until 116
lQ must assume the position indicated by the
- central computer 200, at which also the rota-
tional transmitter and thus the rotatable upper
portion 103 (Figure 5) assumes that position
where the beam pulse is produced for obtaining
the next distance measured value~ The exact
time and spatiàl ~direction) correlation of
the beam pulse is mandatory for the reproduction
. of the distance measured value which is formed
at the pexiphery. This occurs in order to
: 20 avoid undefined differences.
: ~ ' . '
If there are used as the beam pulses optical,
for instance infrared radlatlon pulses,:then
the pulse transmitter 112 (.Figure 6) can have
. . operatively associated therewith a varlo-optical
system or variably focus lens~ 132 ~Figure 6)
:~ .
., . , . .,
~ :., - 57 -
~ ~', , .
.. . . - , . ~ . -.. ~, . . . - .
.. -: . .~ , , ~ : . :
~ ' ' ' ' , ' ::' ,
: 'I ` ' ' ' ' '
~ 7~
and the focal width thereof can be controlled
. by the regulation and control device 130 as
~, a function of the distance measured values.
.-
5. Turning-off the apparatus. Two case are
distinguished namely:
5.1. Turning-off the apparatus within the time
of employment thereof. In this case the
current suppl~ for the computer 400 is
maintained, only the peripheral units con-
- ~ taining measuring and regulation portion
are disconnected from the current supply.
5.2. Turning-of~ the apparatus in general.
All units are disconnected from the current
supply, i.e., placed in a voltageless
condition.
~ . ' ' . .
A further exemplary embodiment now will be explained
based upon Figures 9, 10, 11 and 12. Figure 9 illustrates an
arrangement containlng a beam splitting or dividing system.
~: ~ . .
In Figure 9 reference character 600 designates the
ao beam dividing or splitting system in its entirety, which is
provided when uslng the invention Qr monitoring discrete ,
: :
~ .
~ ~, ~ - 58 -
~'
.,,.. ,.. , . ~ . :, ~ '
.
.
'. ~ .
~z~
~,
.. surfaces, for instance a door opening 601 and a window opening
602 of a building 603. .
~ .,
. The beam splitting system or beam splitter 600 is
connected, on the one hand, with a pulse transmitter 112 and,
on the other hand, With a receiver 125. By means of a trans-
. mitter coupling element 604, for instance a first lens ar-
rangement for coupling a laser diode of the pulse transmitter
112 with glass fibres of a transmission conducting system.605,
composed of one or a number of ~lass fibre bundles, preferably
f different length, the transmisslon energy is infed by means
of the individual fibres of each glass fibre bundle to a
. respectivë transmitting lens 606 of a beam splitter 607 and
~ from such lenses is propogated in the form of transmission
~ beams 608 in different directions in a.surface extending paral-
.~ lel to the door plane. ~ The thus formed transmission or trans-
: mitted beams 608 are~ directed towards the outline or circum-
ference of the door and, then when the door opening is
free, reflected therefrom. Receiving lenses 609 of the beam
. . :collector 610 remove the more or less diffuse reflections of
~ the~recelved beams~6~1 correlated with certain t~ansmitted
; beams,~ these:recelv~d beams 611 traveling opposite to the
:t~ansmltted beams 608. The reoelvlng lenses 609 conduct the
received:energy, by means of the individual fibres of a glass
~fibre bundle o~ a:receiving conducting or transmission system
... ..
~ ~ ~ ~ 29~
612, by means of a further lens system of a receiver coupling
. element 613, to the receiver 125.
,~
Figure 9a illustrates in de~ail the preferably
structurally assembled together beam splitter 607 and beam
collector 610. The lenses 606 and 609 preferably can be struc-
. turally combined in conventional fashion with the relevant endsof the related glass fibres.
~he beam splitt:er system 600 extends from the pulse
transmitter 612 to the monitored surfaces or spaces 6~1, 602
and possibly further surfaces and then again back to the receiver
125. Prefe.rably, the glass fibre bundle belonging to the trans- .
mission conductive system 605 and the glass fibre bundle belong-
ing to the receiver conductive system 612, with optical decoup-
ling, are laid in a common channel, for instance a tube so as
to be protected against damage, for instance inside the building
or structure constituting the monitored region or space 1.
:' ~ . .
In order to obtain directional-dependent information
concerning objects penetrating the monitored spaces or surfaces,
it is possible to carry out monitoring in spatially tandemly
arranged sur~aces, in order to obtain tlmewise differences of
penetration of the surfaces. Preferably~ then, the momentarily
related b m splitt ~ 607 and m collector 610 are arranged
.~
~ '. : ' ' .
.~ 1~ 97~
in neighboring corners of the surfaces or spaces 601 and 60Z
to be monitored.
. ~
The previ.ously described further exemplary embodi-
ment affords an appreciably simplified system design owing to
the ommission of moved components, in particular the structure
of the computer is appreciably simplified in relation to that
of the embodiment of Figure 6.
Figure 10 shows a block circuit diagram of the
described exemplary embodiment containing a beam splitter system
600. The pulse transmitter 112 transmits transmitter beams 608
by means of the generally illustrated beam splitter system 600. .
. The received beams 611 are infed from the beam splitter system
i 600 to the receiver 125. In a manner analogous to the illustra- .-
tion of Figure 6 a computer 400* is provided for controlling the
pulse transmitter 112 and for evaluating the output signals of
~: the recelver 125.
~ ~ : ., . ~ - ' -
.: From the txansit or travel~times of the transmitted
pulses ~rom the output of the transmitter 112 until the rece~tion
of the slqnals rel~ated to the recelved~beams it is possible to
0 :again:form dlstance vectors. It. lS to be observed, however, that
: both the transit tlmes in the beam splitter system 600 and also
~he transit times~in the ~ree space of the monitored surfaces
are incorporated into the~distance vectors E.of such embodiment,
:
. ,
~ 61 - I
, ,, ,. .. ,, ,, , ,, , - - ~ . ,
,'' , ' : :. : , ,
: , - , ,
,, , , ~ ..
,
~ 8
that is to say, mathematically processed.
, The indi~idual blocks of Figure 10 correspond,
in analogous manner, to the blocks designated with the same
reference characters in the arrangement of Figure 6.
With the present further exemplary embodiment the
irradiated or reflecting parts of the door frame or window ~rame,
in the manner heretofore defined, form a respective virtual
line or surface, by means of which there is limited b~ the
radiation the surface (door opening) defined by the beam direc-
1~ tion of the beam splitter 607. Monitoring therefore is limitedto the surface section located within such framed portion and
serving as the actual protected surface or protected space.
. ., ~.
~ If, as mentioned, there are computed the transit
; or travel times, and thus, the received vectors, for instance
at the transmitter output, then there will be recognized from
the showing of Figure 9 that each monitored surface or space,
i.e. spaces 601 and 602 and possibly further spaces or surfaces
can be correlated to a quite specific region, which, in each
instance, results ~rom the sum of the transit time between the
~0 pulse transmitter 112 to the beam splitter 607 plus the travel
time of the transmitted beams. The shortest transmltted beam
at the opening 601 is realized when a disturbing or lntruding
object is located directly at the beam splitter 607. The related
- 62 -
.,:
.,
' , ' ~ ~ - '
.
--~ ~2~7~3 ~
transit time is then the shor~est value which can be determined
in conjunction with the opening 601, and thus, there is here
realized the shortest distance vector. The longest travel time
and therefore the largest distance vector produces at the
opening 601 a diagonally extending transmitted beam 608 or
received beam 611, respectively.
Due to the periodic measuring of each opening
601, 602 and possibly further openings or monitored spaces,-it
is therefore possible to continuously form and store defined
received vectors. Upon intrusion of an object at any one of
the monitored surfaces (openings) there is altered at least
one distance vector in relation to the temporarily stored dis-
tance vector which was heretofore formed for the relevant sur-
face (opening) and direction or directions. Such change ac-
cordingly can be correlated to a certain surface (opening) due
to the correlatability to the xange of distance vectors (transit
times) correlated to the relevant surface (opening).
. .
, - . '
Consequently, there is not only afforded the pos-
sibility of sounding an alarm when an intruder unlawfully enters,
as concerns the polnt in time thereof, but at the same time
there can be carried out an ind~lcation as to the location of
; the intrusion, namely the surface, opening 601, 602 and so
rorth.
:
, ; ~ - 63 -
~ , .
,
,... . . .
: -
~ 9~8
" .~
Figure ll schematically shows the serial evaluation
. o~ the distance vectors E obtained with an arrangement accord-
ing to Figures 9 and 10. The distance vectors E, as mentioned,
correspond to the related transit times, wherefore in the
showing a of Figure ll there has been plotted along the ordinate
both the time t and also the distance E.
The abscissa axis X designates the monitoring site
and is structured such that it corresponds to a point in time
to, for instance the time that the transmitted beam moves out
of the beam splitter 607 located closest to the transmitter 112.
. .,- .
` .
. . The illustration of Figure lla designates three
groups of distance vectors each containiny five distance -
. vectors, wherein the ~irst group is correlated with opening 601,
the seoond with opening 602 and the third with a further open-
~; : ing 614. ' :
: ,, ~ ; ' , ' '. '
--: ~: The full line distance vectors bounded by a point
~ represent the normal:or standard state, i.e. no intrusion of an
:~ object in the opening.
: ~ ~: The:broken~line designa~ed distance vectors, boun-
~ 0~ ded;or ternlnatel ~y a cros~s,~deslgnate the case where an ob-
f ~ ~ ~ect 615 has~ intruded,
~ ~ 64
: ~ ~
.
.. . .
, . .
. ~ ,
:~,' ", - , , ~, ' " '
, . . .
~ ~2997~
These conditions have been shown in the illustrations
of Figures llb, llc, lld, lle.
~. ~
There will be easily recognizèd from Figure 11 that
the transit time range t~ to t5 is to be correlated in the un-
disturbed case to the opening 601, the transit time range t6 to
t7 in the undisturbed case to the opening 602 and the transit
time range t~ to tg to the opening 614. -
. .
If an intruding object 615 occurs, for instance,
at the opening 601, then there o~curs a premature reflection
10 at the object 615 at the bordex of the opening 601. This leads
to shortened transit or travel timestl, t2 and t3 and to shor-
tened distance vectors; the latter have been shown in broken
lines in Figures lla and terminate with a cross. -
~, . .
By comparison of the shortened distance vectors
with the normal distance vectors (full lines) correlated with
the same opening 601, there is realized the point in time and
the location or the opening 601 where an intrusion has occurred.
~ ' . , . .
These are mathematical or arithmetic operations which
. automatically occur by appropriate programing of the computer
400* (Figure 10). There are thus processed in series all of the
individual distance vectors.
~,: : .
' :
~ ~ , - 65 -
~ '''' , . I
-
.~. . .
, , , ~ .
;' ' ' :'~. ' '
~: ' , ' ' ~ . ' .
. ~
~LZ~g7~3
In a simplified case it is possible to determine the
intrusion of an object also with groupwise processing of the
! distance vectors. This will be explained based upon the showing
of Figure 12. If there is employed an electro-optical distance
measuring device of known construction, such as for instance
disclosed in the German Patent Publication No. 2,634,627, as
the receiver 125, then with suitable dimensioning of the system
an input oscillation circuit is commonly driven in each case by
a group of received signals correlated in their entirety to an
0 opening 601, 602 or 614, there~y realizing a groupwise evaluation
of the di-stance vectors. Hence, there is provided only one
received vector per group or opening. While referring to the
condltions according to Figure 11 there will be recognized for
the undisturbed case a respective common distance vector E 601,
E 602, E 614, shown in Figure 12 by full lines ~erminating at a
point.
: ' . . , .
If an object 615 appears at the opening 601 then
there~is shortened the related distance vector, as indicated in
Figure 12a by the broken line designated by E 601* and termina-
~0 tlng with a cross. The occurrence oE such shortened distancevector constitutes a sign for the penetration of object 615 into
the opening 601 or other monitored space.
: ' ~ : '
WhiIe there are shown and described present preferred
embodiments of the invention, it is to be distinctly understood
, that the invention is not limited thereto, but may be otherwise
variously embodled and practiced within the scope of the following
claims. ACCORDING~Y,
o6
. .
. . .
.. .. ..
. ~ ~ . . . . .
~ , . .
