Note: Descriptions are shown in the official language in which they were submitted.
CA 02770465 2012-03-02
SCALE FOR PLAYING SURFACE IN SPORT OF CURLING
FIELD OF THE INVENTION
The present invention relates to a scale for use in the sport of curling
which provides a visual gauge to determine the amount of curl in the lateral
direction
of curling stones thrown longitudinally along the sheet of ice during a
curling match.
In one embodiment, the scale is set in the sheet of ice together with other
markings
forming the playing surface in the sport of curling. In a further embodiment
the scale
is shown with a graphical representation of a curling rock being thrown on a
video
display.
BACKGROUND
In the sport of curling, players typically throw stones in a longitudinal
direction along a sheet of ice from a throwing area to a target area with some
rotation
being provided to the curling stone such that the curling stone follows a
curved path
which displaces the stone over a prescribed lateral distance between the
initial
location where the stone was targeted and the final resting position of the
stone. The
player known as the skip which typically places the target curling broom at
which the
curling stones are directed attempts to predict the prescribed lateral
distance resulting
from the curling rotation of the curling stones so that the target broom can
be placed
laterally offset from the desired placement of the stone by the appropriate
amount.
Because of the differences in speed of the curling stone in the longitudinal
direction
depending upon the type of shot being made and the differences in ice
conditions,
estimating the prescribed lateral distance can be very subjective. Although
experienced curlers can estimate the prescribed lateral distance well from
learned
experience, it is often difficult for beginners or those who have difficulty
in visually
measuring and calculating the lateral distance from the previous shots to
properly
CA 02770465 2012-03-02
2
place the target broom.
SUMMARY OF THE INVENTION
According to one aspect of the invention there is provided a playing
surface in the sport of curling comprising:
a sheet of ice which is elongate in a longitudinal direction between a
throwing area at a front end and a target area at a rear end; and
a plurality of markings set into the sheet of ice comprising:
a concentric set of target rings defining a house in the target area
at the rear end;
a scale in the target area which extends in a lateral direction
perpendicularly to the longitudinal direction of the sheet of ice, the scale
comprising a
plurality of indicia at evenly spaced positions in the lateral direction.
According to a second aspect of the present invention there is provided
a scale for use in a playing surface in the sport of curling in which the
playing surface
comprises a sheet of ice which is elongate in a longitudinal direction between
a
throwing area at a front end of the sheet of ice and a target area at a rear
end of the
sheet of ice, the scale comprising:
a flexible substrate which is elongate in a first direction and which is
arranged to be set in the sheet of ice such that the first direction is
substantially
perpendicular to the longitudinal direction; and
a plurality of indicia printed on the flexible substrate at evenly spaced
positions in the first direction.
The scale according to the present invention can be regularly used as a
reference to more easily visually measure the prescribed lateral distance that
curling
stones move between the target broom and the actual final resting place of the
curling
CA 02770465 2012-03-02
3
stone due to the curved curling path of the stone. The skip of a curling team
can thus
further reference the scale to more appropriately place the target broom on
subsequent shots being made.
The scale may extend through a longitudinal centre of the house,
adjacent a front end of the house, adjacent a rear end of the house, or any
combination thereof.
Preferably the scale includes a plurality of the indicia per foot of length in
the lateral direction. For example the indicia may be spaced apart by 1 inch,
1
centimetre or 1 millimetre.
The indicia preferably comprise numbers in numerical order. The
numbers may be in ascending order from one end of the scale to an opposing end
of
the scale, or alternatively the numbers may be in ascending order from a
lateral
centre of the house towards each of two opposing ends of the scale.
The scale preferably spans a width in the lateral direction which is
greater than the house.
When the scale comprises a flexible substrate which is elongate in a first
direction and which is arranged to be set in the sheet of ice such that the
first direction
is substantially perpendicular to the longitudinal direction, the plurality of
indicia may
be printed on the flexible substrate such that a background of the flexible
substrate is
lighter in color than the indicia.
In further embodiments, there may also be provided a longitudinal scale
which extends in the longitudinal direction of the sheet of ice. The
longitudinal scale
preferably also comprises a plurality of indicia at evenly spaced positions in
the
longitudinal direction.
According to a further aspect of the present invention there is provided a
CA 02770465 2012-03-02
4
scale system for use in the sport of curling in which the playing surface
comprises a
sheet of ice which is elongate in a longitudinal direction between a throwing
area at a
front end of the sheet of ice and a target area at a rear end of the sheet of
ice and has
a width in a lateral direction which is perpendicular to the longitudinal
direction, the
system comprising:
a tracking tool arranged to determine a lateral position in the lateral
direction of the sheet of ice of a curling stone on the sheet of ice relative
to a lateral
scale substantially representing a width of the playing surface in the lateral
direction;
and
a controller arranged to generate real time display information
representing the lateral scale and the lateral position of the curling stone
on the scale
as the lateral position of the curling stone varies as the curling stone is
thrown along
the sheet of ice in the longitudinal direction such that the display
information is
arranged to be displayed on a video display in real time.
The tracking tool and controller are particularly suited for use in
television broadcasts of the sport of curling to provide spectators watching a
video
feed with an additional perspective of the curling match.
The controller may be arranged to generate the display information
representing the scale and the lateral position of the curling stone on the
scale on a
portion of a video monitor or as an overlay onto a real time video stream.
In some embodiments the tracking tool comprises a sensor arranged to
electronically locate the lateral position of the curling stone relative to
the sheet of ice.
Alternatively, the tracking tool may perform simply by analyzing the
video captures from a camera having a known position and orientation relative
to the
sheet of ice. In this instance, the track preferably includes: i) an input
arranged to
CA 02770465 2012-03-02
receive a real time video stream comprised of sequential video frames of a
curling
stone thrown along the sheet of ice in the longitudinal direction; and ii) a
video image
analyzing tool arranged to identify in real time within each video frame a
location of
the lateral scale relative to the sheet of ice and a location of the curling
stone relative
5 to the lateral scale. Preferably the controller is then arranged to generate
the display
information representing the scale and the lateral position of the curling
stone on the
scale as graphical representation overlaid onto the video stream in real time.
Preferably the controller is arranged to generate the display information
such that the scale is graphically represented and the lateral position of the
curling
stone is graphically represented as an icon movable along the scale.
When the system further includes a broom locating tool arranged to
locate a lateral position of a broom of a skip relative to the scale,
preferably the
controller is arranged to generate the display information such that the
display
information includes a representation of the lateral position of the broom.
The broom locating tool may comprise a sensor arranged to
electronically locate the lateral position of the broom.
Preferably the controller is arranged to generate the display information
such that the scale is graphically represented and the lateral position of the
broom is
graphically represented as an icon movable along the scale.
The display information preferably also includes a representation of a
lateral position of a center line of the playing surface.
Various embodiments of the invention will now be described in
conjunction with the accompanying drawings in which:
BRIEF DESCRIPTION OF THE DRAWINGS
Figure 1 is plan view of the playing surface according to a first
CA 02770465 2012-03-02
6
embodiment.
Figure 2 is a plan view of the scale according to a first embodiment.
Figure 3 is a plan view of the scale according to a second embodiment.
Figure 4 is a plan view of the playing surface according to a further
embodiment.
Figure 5 is schematic representation of a video frame from a video
camera feed of a curling match in the sport of curling incorporating the scale
system
of the present invention therein; and
Figure 6 is a schematic representation of the scale system according to
Figure 5.
In the drawings like characters of reference indicate corresponding parts
in the different figures.
DETAILED DESCRIPTION
Referring to the accompanying figure there is illustrated a lateral scale
generally indicated by reference numeral 10. The lateral scale 10 is
particularly suited
for use on the playing surface 12 in the sport of curling.
More particularly, the lateral scale 10 is suited for use with a playing
surface comprising a sheet of ice 14 extending in a longitudinal direction
between a
front end 16 and a rear end 18. When throwing the curling stones in a first
direction
along the sheet of ice, the front end comprises a throwing area and the rear
end
functions as a target area. Typically the sheet of ice permits throwing of
stones in the
opposing second direction by providing the rear end with all of the features
of the
throwing area and the front end with all of the features of the target area
also to permit
playing in either direction. The features of the playing surface as initially
described
herein relate to throwing of the stones in the first direction from the front
end 16 to the
CA 02770465 2012-03-02
7
rear end 18.
In the first direction, a first set of hacks 20 is located at the front end 16
to define a starting position of a person throwing a curling stone. A first
hog line 22 is
spaced from the front end to define a throwing area between the hacks 20 and
the
hog line 22. The hog line defines the point where the thrower must release the
curling
stone as it is thrown towards the target area. A second hog line 24 is located
nearer
to the rear end of the sheet of ice but is spaced therefrom so as to define
the target
area between the second hog line 24 and a back line 26 at the rear end of the
sheet
of ice.
A set of concentric rings 28 including a 12 foot diameter ring, an 8 foot
diameter ring, a 4 foot diameter ring, and a central button circle. The set of
rings 28
are adjacent to the back line 26 and spaced from the second hog line 24 so as
to
define the house area where points are counted. A tee-line 30 typically
extends in a
lateral direction so as to be perpendicular to the longitudinal direction to
the sheet of
ice so that the tee-line extends through the longitudinal center of the rings
28. The
first and second hog lines and the back line are also oriented in the lateral
direction so
as to be parallel to one another.
Optionally, a center line extends longitudinally across the sheet of ice
through the lateral center of the set of rings 28. The various markings
including the
hog lines, the back line, the tee-line, and the set of rings can all be set in
the ice in the
form of tape or paint and the like.
The lateral scale 10 comprises a flexible substrate 32 which is elongate
in a first direction. The substrate is a flat strip of material, for example
plastic or a
woven cloth material which is non-elastic to maintain an accurate length. The
material is suitable for being set in the sheet of ice between layers of ice
as the ice is
CA 02770465 2012-03-02
8
formed.
A plurality of evenly spaced indicia 34 is printed on the flexible substrate
such that the indicia are evenly spaced apart in the first direction along the
full length
of the substrate. The overall length of the substrate is greater than the
diameter of
the house such that when the substrate is set into the ice to extend in the
lateral
direction, the lateral scale is wider in the lateral direction than the
outermost 12 foot
diameter ring 28 of the rings defining the house.
The indicia include suitable markings at evenly spaced positions
together with printed numbers associated with the markings for measuring
distance in
the lateral direction. Typically the background color of the substrate is very
light in
color, for example white, with the indicia being darker printing on the
lighter
background for optimal visibility and to minimize heat absorption.
As shown in Figure 1, the preferred location for the lateral scale is to sit
the flexible substrate 32 in the sheet of ice at the location of the tee-line
30. In this
instance the lateral scale protrudes outwardly beyond the set of rings at both
laterally
opposed ends of the lateral scale. Additional markings may be provided on the
lateral
scale corresponding to the intersection of the rings with the lateral scale so
that the
borders of the rings are still visible when overlaid by the flexible substrate
of the
lateral scale.
As shown in Figure 2, in some instances the printed numbers of the
lateral scale start at one of the ends of the substrate and increase in
numerical order
across the full length of the lateral scale to the opposing end of the
substrate. The
markings preferably are spaced near enough together on the lateral scale so as
to
locate several markings for each linear foot. For example the markings may be
spaced apart by one millimetre, one centimetre, or one inch, or any other
consistent
CA 02770465 2012-03-02
9
spacing.
In an alternative arrangement shown in Figure 3, the numerical indicia
may start at the centre line where a zero is located such that the numbers
increase in
numerical order from the centre in both directions towards each of the two
opposed
outer ends of the lateral scale.
As shown in Figure 4, although the lateral scale preferably remains
oriented in the lateral direction, the position of the lateral scale in the
longitudinal
direction can be varied from the tee-line location of Figure 1 to an
alternative location
at the front end or the back end of the house. In yet further arrangements
multiple
lateral scales may be provided such that a scale may be located at one or more
of the
following locations: in the guard area between the house and the hog line, at
the front
of the house, at the T-line 30, or at the back line 26 at the rear of the
house.
In addition to the lateral scale 10 described above, there may also be
provided a longitudinal scale 50 for use together with or independently of the
lateral
scale. As shown in Figure 1, the longitudinal scale 50 is positioned along the
centre
line to span the full length of the sheet of ice between the opposing back
lines 26.
The longitudinal scale 50 is preferably substantially identical to the lateral
scale in that
it comprises a flexible substrate with numeral indicia printed thereon,
preferably in the
format of the embodiment of Figure 2, so as to be arranged to be set into the
ice in a
similar manner.
Turning now of Figures 5 and 6 a further embodiment of the scale
system 100 is illustrated also for use in indicating the lateral position of a
curling stone
when the curling stone is captured on a video feed. The system 100 displays
both a
lateral position of a curling stone and of a skip's broom on a scale 102 which
appears
as an overlay onto a realtime video stream 104. The system 100 is thus
particularly
CA 02770465 2012-03-02
suited for use in television broadcasts of the sport of curling to provide
spectators
watching a video feed with an additional perspective of the curling match.
The system includes a curling stone tracking tool 106 arranged to
determine a lateral position in the lateral direction of the sheet of ice of a
curling stone
5 on the sheet of ice as the lateral position of the curling stone varies as
the curling
stone is thrown along the sheet of ice in the longitudinal direction. More
particularly,
the stone tracking tool is arranged to determine a lateral position of the
curling stone
relative to a lateral scale substantially representing a width of the playing
surface in
the lateral direction.
10 According to a first embodiment, the tracking tool may be a sensor
arranged to electronically locate the lateral position of the curling stone.
For example,
existing sensors in the handle of a curling stone which are used for detecting
a
hogline violation may also be sensed by auxiliary sensors which can determine
the
lateral position of the curling stone. Alternatively, GPS or RF type sensors
may be
used to locate the lateral position of the curling stone as it is displaced
longitudinally
during a curling shot.
The system can also include a broom locating tool 108 arranged to
locate a lateral position of the broom of the skip. According to a first
embodiment, the
broom locating tool may also be a sensor arranged to electronically locate the
lateral
position of the broom using GPS or RF signals for example. Alternatively, the
broom
locating tool may be manually input into the system by an operator of the
system.
A controller 110 is arranged to display the scale onto a portion of a
suitable video monitor display screen 112 or video stream such that the scale
substantially represents a width of the playing surface in the lateral
direction. The
controller is also arranged to display the scale and the lateral positions of
the curling
CA 02770465 2012-03-02
11
stone and the skip's broom on the scale. More particularly, the controller
generates
real time display information representing the lateral scale and the lateral
position of
the curling stone on the scale as the lateral position of the curling stone
varies as the
curling stone is thrown along the sheet of ice in the longitudinal direction
such that the
display information is arranged to be displayed on a video display in real
time. The
controller is thus able to generate the display information on a portion of a
video
monitor or as an overlay onto the real time video stream.
In the preferred embodiment, the controller is arranged to display the
lateral position of the curling stone as a first icon 114 movable along the
scale in
realtime and the broom as a second icon 116, also movable along the scale.
Typically a lateral position of a center line of the playing surface is also
displayed on
the scale by suitable indicia 118.
In an alternative embodiment of the tracking tool, minimal sensing
equipment is required at the playing surface area as the location of the
curling stone
relative to the lateral scale can instead be determined by analyzing a real
time video
stream comprised of sequential video frames of a curling stone thrown along
the
sheet of ice in the longitudinal direction. In this instance the tracking tool
includes an
input arranged to receive the real time video stream and a video image
analyzing tool
arranged to identify in real time within each video frame a location of the
lateral scale
relative to the sheet of ice and a location of the curling stone relative to
the lateral
scale. The video stream in this instance is typically captured from a camera
positioned to be laterally centered at one end of the sheet of ice either at
ice level or
spaced above the sheet of ice to be directed at a downward inclination towards
the
ice. In either instance, the camera is typically directed substantially in the
longitudinal
direction of the sheet of ice to capture images of the curling stone as it is
displaced
CA 02770465 2012-03-02
12
longitudinally along the ice towards the camera.
The controller in this instance may then be arranged to generate the
display information representing the scale and the lateral position of the
curling stone
on the scale as graphical representation overlaid onto the video stream in
real time
such as an auxiliary scale 102 separate from the sheet of ice or as an in situ
scale
102' aligned with the sheet of ice as shown in Figure 5. In the instance of an
auxiliary
scale 102 which is graphically represented, the lateral position of the
curling stone is
graphically represented as the icon 114 movable along the scale.
According to a second embodiment of the broom locating tool 108, the
lateral position of the broom of the skip relative to the scale can also be
determined
with the image analyzing tool such that the controller is arranged to
subsequently
generate the display information to include a representation of the lateral
position of
the broom. When the scale is graphically represented, the lateral position of
the
broom can also be graphically represented as an icon movable along the scale.
Since various modifications can be made in my invention as herein
above described, and many apparently widely different embodiments of same made
within the spirit and scope of the claims without department from such spirit
and
scope, it is intended that all matter contained in the accompanying
specification shall
be interpreted as illustrative only and not in a limiting sense.
