Note: Descriptions are shown in the official language in which they were submitted.
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A method and system for providing haptic effects
FIELD OF THE INVENTION:
This invention relates to virtual effects, more specifically to a method and
system for providing haptic effects associated with an image on a display.
BACKGROUND OF THE INVENTION:
o In many new applications, the implementation of extra functionality to a
product has resulted in applications that are more desirable to consumers
(e.g. extra
vehicle control functions in automobiles). In other cases, the extra
functionality is a
necessity resulting from the increasing complexity of the overall system (e.g.
flight
control systems in military aircraft). This presents a challenge for the user
of the
product/device, since easy access to all the functions can be distracting to
the normal
operation. f~loreover, interfaces that are fixed and not re-configurable can
limit the
number of functions that are implemented and can also prevent the interface
from
operating in an intuitive fashion.
The addition of the sense of touch to the user interface allows the user to
2o navigate through the options primarily based on the sense of touch, instead
of relying
on visual feedback only. Furthermore, the reconfigurability of the device
allows the
interface to be designed in an intuitive fashion. Therefore, the addition of
haptic
effects to a display device has clear benefits.
However, in the past, when conventional haptic devices have been integrated
25 into display devices, they have tended to be quifie expensive and they
typically
obstruct.the view of the display.
To overcome the obstruction issue, some applications have separated the
haptic device and the display (e.g. the force feedback joystick is located on
a control
console with the display located on the dashboard). However, this creates
3o disconnect between what is seen and what is felt.
Other applications are limited to implementing haptic effects using only
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2
vibration devices. Specifically, in these applications, when a user passes
over a
particular area of the display, the user senses a vibration effect. While this
provides
some haptic feedback to the user, the user still needs to correlate a certain
type of
vibration to a specific meaning.
Some other applications use a virtual world approach as described, for
example, in U.S. Patent No. 5,986,643. In this approach, the user is required
to wear
a glove that has several actuators built-in and a virtual goggle heads up
display. As
the user reaches out to touch an object that is projected on the virtual
goggle display,
the actuators are enabled to apply force to individual fingers. This approach
is
o complex and expensive.
Therefore, it is desirable to provide a new haptic device and method, which
can meet that demands of scalability, reliability, reconfigurability and cost
reduction.
SUIi/llI~IARY ~F THE IN~ENTI~N:
It is an object of the invention to provide a novel haptic device and system
that
obviates or mitigates at least one of the disadvantages of existing systems.
In accordance with an aspect of the present invention, there is provided a
system for providing haptic effects to a user, which in eludes a display for
providing an
o image of an object; and a transparent overlay haptic device. The device
includes: a
transparent overlay for translating the motion of the user's finger to the
image and
providing haptic effects to the user and a haptic effect element for
generating the
haptic effect on the overlay in response to the motion of the user. The user
contacts
the image through the overlay.
The transparent overlay haptic device may include the overlay, the actuator
(active or passive), the position sensor (absolute or relative), the
controller and the
electrical and mechanical interfaces between the components.
In accordance with a further aspect of the present invention, there is
provided
a method of passively or actively applying a force in the x and y axis to a
user's finger,
3o via a transparent overlay, in such a way that does not obstruct the view of
the display,
to simulate haptic effects.
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The transparent overlay haptic method of the present invention achieves the
reconfigurability of the haptic effects generated on the device to match the
display
objects.
Other aspects and features of the present invention will be readily apparent
to
those skilled in the art from a review of the following detailed description
of preferred
embodiments in conjunction with the accompanying drawings.
BRIEF DESCRIPTION OF THE DRAWINGS:
The invention will be further understood from the following description with
reference to the drawings in which:
Figure 1 shows a schemafiic diagram of a transparent overlay haptic system
1~ including a transparent overlay haptic device and a display in acc~rdance
with an
emb~diment of the present invention;
Figure 2 shows a schematic diagram of the main components of the
transparent overlay haptic system of Figure 1;
Figure ~A shows a schematic top view ~f the transparent ~verlay haptic device
2o in accordance with a first embodiment ~f the present invention;
Figure 3B shows a schematic side view of the transparent overlay haptic
device shown in Figure 3A;
Figure 4 shows one example of wall/edge haptic effects;
Figure 5 shows one example of detent haptic effects;
25 Figure 6A shows a schematic top view of the transparent, overlay haptic
device
in accordance with a second embodiment of the present invention;
Figure 6B shows a schematic side view of the transparent overlay haptic
device shown in Figure 6A;
Figure 7A shows a schematic top view of the transparent overlay haptic device
3o in accordance with a third embodiment of the present invention;
Figure 7B shows a schematic side view of the transparent overlay haptic
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device shown in Figure 7A;
Figure 8A shows a schematic top view of the transparent overlay haptic device
in accordance with a fourth embodiment of the present invention; and
Figure 8B shows a cross-section view taken along the line A-A in Figure 8A.
Figure 9 shows a schematic diagram of the transparent overlay haptic device
in accordance with a fifth embodiment of the present invention;
Figure 10A shows a schematic top view of the transparent overlay haptic
°device in accordance with a sixth embodiment of the present invention;
Figure 1 OB is a schematic side view of the transparent overlay haptic device
o shown in Figure 10A; and
Figure 11 shows one example of a position sensor shown in Figure 1.
DETAILED DESCRIPTI~N ~F THE PREFERRED EMB~DIMENTS:
Figure 1 illustrates the basic concept for the use of a transparent overlay
haptic device 10 in accordance wifih an embodiment of the present invention.
The
transparent overlay haptic device 10 is a virtual touch/haptic device that can
be used
over top of a display 20. The transparent overlay haptic device 10 provides
haptic
effects to the user 12, corresponding to objects created on the display 20,
without
obstructing the view of the display.
The display 20 creates images that are used to represent difFerent objects 14
and would be present on a user interface, e.g. dials, sliders or buttons. The
user
"feels" the objects by touching the transparent overlay haptic device 10 and
moving
his finger across fihe display 20. As the user's finger 12 passes over the
image of an
object, a haptic effect is generated to simulate the user making contact with
fihe
object.
Figure 2 illustrates the main components of a transparent overlay haptic
system 5 having the device 10 and display 20 of Figure 1, and the illustration
can be
used to explain how the haptic effects are implemented. The transparent
overlay
3o system 5 contains the display 20 and the transparent overlay~haptic device
10 which
has a transparent overlay 22, one or multiple actuators 24, a position sensor
26, a
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controller 28, and housing and other mechanical interfaces.
The transparent overlay 22 lies over the display 20 between the user's hand
12 and the display 20. The transparent overlay 22 is a thin, flexible film
that allows
the force of the user's hand 12 to be transmitted through to the display 20.
When the
5 user makes contact with the overlay 22, there is sufficient friction between
the user's
finger and the overlay 22, and minimal friction between the overlay 22 and the
display
20,, so that the overlay 22 easily moves with the user's finger. Hence the
overlay 22
does not move, relative to the user's hand 12. In Figure 2, the overlay 22 is
larger
than the display 20, and an actuator 24 is located in the vicinity of the
overlay 22, but
0 out of the field of view of the display 20. The actuator 24 mechanically
interfaces with
the overlay 22 through a mechanism to impart a force on the overlay 22.
Therefore,
when the actuator 24 is engaged, this force can be transmitted to the user's
finger, via
the overlay 22, without obstructing the view of the display 20. The position
of the
user's finger is obtained by the position sensor 26, and is transmitted to the
controller
28. The controller 28 contains the software and hardware interfaces to allow
for the
processing of the sensor information to control the actuators 24 to simulate
the
desired haptic effects, and for the communication to external subsystems via a
communication bus interface 30.
The position sensor 2G records, the initial position of the finger. The
position
2o sensor 26 also records the new position of the finger as the user moves the
overlay
22 across the display 20. When the user touches an area on the display 20 via
the
overlay 22, which is to provide a force feedback, fihe controller 28 processes
sensor
signals to generate haptic effects on the overlay 22. The homing device may
include
helical spring, elastic, coil spring, pulleys, sliders or gas spring. The
position sensor
26 may include a photo sensor or an optical sensor.
The display 20 may be a touch sensitive Liquid Crystal Display (LCD). In this
case, the position of the user's finger is obtained directly from the LCD 20,
and is
communicated to the controller 28. As the user moves their finger, and thus
the
transparent overlay 22, over an object that requires a haptic effect (e.g. a
line
3o denoting the edge of a button), the controller 28 detects this collision
and sends a
signal to the actuator 24 that in turn applies a force to the overlay 22: The
force is
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sensed by the user as a resistance to the desired motion.
If a "bump" type haptic effect is required to simulate the edge of a button,
then
the actuator 24 may be engaged for a short period of time with a large force.
Many
other effects can also be simulated. Once the user is within the boundary of a
button
object 14 on the display 20, the actuator 24 is partially engaged. Thus,
additional
friction is felt by the user while inside the button object 14.
Figure 3A shows a top view of the transparent overlay haptic device 1 OA in
accordance with a first embodiment of the present invention. Figure 3B shows a
side
view of the transparent overlay haptic device 10A of Figure 3A.
o The overlay 22 of the transparent overlay haptic device 10A is a flat
rectangular clear sheet. The overlay 22 is thin enough to allow forces applied
by the
user's finger to pass through to the touch sensitive LCD display 20. The
overlay 22 is
large enough so that when starting from the home position, the user can place
their
finger anywhere within the display area 42 and move to any new position,
without
15 causing the edge of the overlay 22 t~ pass within the display area 42. The
corners ~f
the overlay 22 are attached to an overlay homing mechanism.
The transparent overlay haptic device 10A includes an overlay homing
assembly 44 for the overlay 22. The homing mechanism 44 includes four springs
46
attached br~t~eeen the four corners of the ~verlay 22 and four spring mounting
p~sts
20 4~ grounded to the base 40 of the device 10A. They may be linear in nature,
~r may
be part of a more complex torsional spring mechanism. 1/Vhen the user is not
making
contact wifih the device 10A, the springs 46 pull the overlay 22 to a home
position.
The spring constant for each spring is sufficient to overcome friction between
the
overlay 22 and any other component of the device, but is small enough not to
add
25 significant force to the user's finger when the overlay 22 is moved by the
user.
The transparent overlay haptic device 10A includes an actuator assembly 48.
The actuator assembly 48 includes a solenoid 50, a brake pad 52 and a brake
pad
bracket 54. The solenoid 50 is mounted on the base 40 of the device 10A
directly
below the brake pad 52, which is held in place by the brake pad bracket 54.
The
30 overlay 22 passes between the solenoid 50°and the brake pad 52.
Figure 3A shows
two actuator assemblies that are positioned on the device 10A to eliminate
rotation
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7
of the overlay 22 when the actuators have been activated. However, if the
mechanical design of the housing prevents rotation of the overlay 22 when one
actuator is activated, the second actuator assembly can be removed. When the
solenoid 50 is activated, the overlay 22 is pinched between the solenoid shaft
and the
brake pad 52. The solenoid 50 is driven at various levels to generate various
levels
of force. This can be utilized to generate a variety of haptic effects.
The display 20 of the transparent overlay haptic device 10A is a touch panel
LCD. The touch panel LCD 20 is used to display objects as well as provide
position
feedback for the user's finger.
o The transparent overlay haptic device 1 OA includes the controller 28 as
shown
in Figure 2(not shown in Figures 3A-3~). The hardware within the controller 28
of the
device 10A includes actuator drive circuitry, position sensing interface
circuitry, a
microprocessor and memory. The actuator drive circuitry takes a signal from
the
microprocessor and drives the actuator. The drive circuitry scheme can be any
one
5 of a number of solenoid actuation schemes. For ea~ample, a pulse width
modulation
scheme or a variable current source scheme could be used. The position sensing
circuitry interface conditions the signal coming from the position sensor and
makes it
available to the microprocessor. The memory is used to store the software that
is,run
on the microprocessor. The microprocessor loads up the software sfiored in
memory
2o and executes the application.
The software of the controller 28 contains the instructions needed to process
the position sensor information to determine the drive signal for the
actuator. The
software supports simulation of a variety of effects. The software also
contains
instructions to generate audio feedback to the user. The software for
simulating any
25 objects on the display 20, haptic effects' and other effects feedback to
the user are
reprogramable.
The haptic effects are now described in detail. The transparent overlay haptic
device 10A provides walls/edge effects, detent effects and damped region
effects to
the user. The device can also provide other haptic effects, such as a variety
of types
30 of gravity wells, friction, areas of repulsion, simulated inertia,
simulated springs,
simulated damping and other effects which can be created by those
knowledgeable
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in the art.
The walls/edge effects are described in detail. Figure 4 shows the wall/edge
haptic effects. As shown in Figure 4, two types of walls can be created. A
thin wall
haptic effect 60 can be described as a barrier that briefly holds the overlay
in a fixed
s position when the user collides with the object. Therefore, as the user
passes
through a wall, they sense a "bump". The sensed "thickness" of the wall can be
adjusted by modifying the force applied to the actuator and the amount of time
that
the solenoid remains enabled.
A thick wall haptic effect 62 can be described as a barrier that prevents the
1o user from entering an area. This effect is implemented as a highly damped
region
(described later) where the solenoid 50 is engaged and held when the user's
finger is
located inside the wall. For the user to exit out of the wall, some slippage
between the
user's finger and the overlay 22 is required. However, the touch sensitive LCD
20 is
able to detect the absolute position of the user's finger, even if there is
slippage
15 between the user's finger and the overlay ~~. Once the user's finger is
outside the
thick wall, the solenoid 50 is disengaged.
The detest effects are described in detail. Figure 5 shows detest haptic
effects. As shown in Figure 5, detests can be implemented as a series of thin
walls
placed in s~accessi~n. The detests can be arranged in a linear or angular
2o configuration. As the user passes over the decent area, they pass through
the thin
walls, and they sense small ridges. The force for detests is typically smaller
that
those used for thin walls. However, the "feel" ~f the detests is adjustable as
well by
modifying the force, duration and spacing between each thin wall.
The damped region effects are now described in detail. The damped region is
2s an area where the solenoid 50 is engaged, but only to a level that adds a
certain
amount of friction to the motion of the overlay 22. This resistance to motion
is sensed
by the user as an area where their motion is damped or restricted. The degree
of
restriction can be adjusted by modifying the level of force applied by the
solenoid 50.
Other haptic effects, which have not been discussed in detail here, can also
be
3o created with this haptic device by those knowledgeable in the art.
These haptic effects can be combined to create objects. A button may be
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9
created by using thin walls that surround a damped area. A slider may be
created by
using a series of detents within a damped area. A slider may be created by
using
damped area where the level or restriction is increased as the user slides
along the
damped area.
These effects and objects are only a few examples, and more complex effects
and objects are provided by the transparent overlay ~aptic device 10A.
Combined with the touch panel LCD 20, the transparent overlay haptic device
10A has two and one half degrees of freedom; translation in the x-axis, y-axis
and a
selection in the z-axis. The touch pad of the LCD 20 can detect when the user
o presses down on the display. The device 10A affords enough haptic degrees of
freedom to implement unique effects corresponding to different control devices
(e.g.
knobs, buttons, sliders, etc.). The haptic effects are generated in a passive
manner.
~nly a braking action is applied to the overlay 22 in order to generate the
haptic
effects. This is in contrast to many more expensive haptic devices where
motors are
15 used to generate the haptic effects.
The overlay 22 is returned to a home position after the user breaks contact
with the device. Without a homing mechanism, the overlay 22 may be railed to
the
limits of the device on subsequent user motions. In the event of a failure of
the
transparent overlay haptic device 10A (e.g. brolaen spring), the user can
still interact
2o with the applicafiion via the touch sensitive LCD 20, and only loses the
haptic effects.
Hence, only partial functionality is lost in the event of a failure. The
software contains
instructions to generate audio feedback to further assist the user in
determining
where the user's finger is located on the display 20.
Figure 6A shows a top view of a transparent overlay haptic device 10B in
25 accordance with a second embodiment of the present invention. Figure 6B
shows a
schematic side view of the transparent overlay haptic device 10B shown in
Figure 6A.
The transparent overlay haptic device 10B includes a clear overlay 22A, a
roller 70 for
rotating the clear overlay 22A in x-axis, and a roller mounting 72 for the
roller 70. The
transparent overlay haptic1 OB further includes a brake actuator 76 (such as a
so solenoid) and the brake pad 74 as the barking mechanism for the overlay
22A. The
brake actuator 76 may be a hydraulic cylinder, pneumatic cylinder.
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The transparent overlay haptic device 10A shown in Figures 3A-3B has two
and a half degree of freedom (two degrees of freedom for the x and y axis plus
0.5
degrees of freedom for the z-axis). The transparent overlay haptic device 1 OB
shown
in Figures 6A-6B reduces the number of degrees of freedom to one and a half
(one
s dgree of freedom for the x axis plus 0.5 degrees of freedom for the z-axis),
which
allows for the considerable reduction in size of the invention. The reduction
in size is
accomplished by eliminating haptic effects in the y-axis and by converting the
overlay
sheet 22A to an overlay roll. The transparent overlay haptic device 10B only
needs
to be slightly bigger than the display 20.
1o The transparent overlay haptic device 10B also allows for the easy
incorporation of motors into the design. This allows for the generation of
more
complex haptic effects since the actuation becomes active. The difference
between
a passive device and an active device is that the passive device relies on the
user to
generate effects, while the active device can generate the effects
independently of
the user. For example, if the user holds Their finger in a fixed location, the
passive
device cannot generate any force on the user's finger while the active device
can.
There is also no need for a homing mechanism (either a passive spring
mechanism or active motor drive mechanism) in the transparent overlay haptic
device
10B since the overlay 22A only moves in one a3~is and the c~ntinu~us roll of
overlay
2o material is fed back over the disphy area as the user moves Their finger.
Figure 7A shows a top view of a transparent overlay haptic device 10C in
accordance with a third embodiment of the present invention. Figure 7B shows a
schematic side view of the transparent overlay haptic device 10C shown in
Figure 7A.
The transparent overlay haptic device 10C keeps the two and a half degrees of
freedom, but still reduces the size of the overall device in one axis (by
using the
concept of a roll of overlay instead of a sheet).
The transparent overlay haptic device 10C combines some of the advantages
of the transparent overlay haptic device 10A in Figure 3 (i.e. 2.5 degrees of
freedom)
and some of the advantages of the transparent overlay haptic device 10B in
Figures
6A and 6B (i.e. reduction in size). In the device 10C, a homing mechanism 46A
(such
as a spring) is provided for one direction (i.e. y-axis), but not in direction
of the roller
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11
motion (i.e. x-axis). This embodiment also allows for the easy incorporation
of motors
into the design (i.e. convert the device to an active device).
Figure 8A shows a schematic top view of a transparent overlay haptic device
10D in accordance with a fourth embodiment of the present invention. Figure 8B
shows a schematic cross side view of the transparent overlay haptic device 10D
shown in Figure 8A. The transparent overlay haptic device 10D keeps the two
and
one half degrees of freedom and significantly reduces the size of the device,
at the
cost of forcing the user place their finger at a predefined location.
In Figures 8A-8B, the full overlay has been replaced with strips of overlay
film
1o that pass over one set of rollers 70A for the x-axis and another set of
rollers 70B for
the y-axis. Two strips 22B and 22 C are shown in Figures 8A-8B. The two strips
228,
22C are attached together where the two strips intersect above the display 20,
and
a divot 80 is placed at the same location. The user places their finger on the
divot 80
when they make contact wifih the device 10D. ~ptional homing mechanisms 4~6A,
~~6B, such as springs, ensure that the divot 80 is returned to the h~me
position (e.g.
the lower left corner of the display) once the user removes their finger from
the
device. Each roller 70A, 70B can slide along a spline axle (perpendicular to
the axis
of rotation) and the axle is attached to the spline mounts 82 through spline
bearings
84 that allow the az~le to rotate. In Figures 8A-8B, x-aazis splines 90 and y-
a~~is splines
92 are shown. As the axle rotates, the roller also rotates, which causes the
overlay
strip to pass over the roller, thus moving the divot 80 in one axis. A disc 78
is
mounted on the axle at a fixed distance from the mount 82 and is part of the
braking
system. The solenoid brake actuator 76 with the brake pad 74 is mounted
opposite
the disc 78 so that when the solenoid is engaged, the disc rotation is
restricted, which
in turn, will restrict the divot 80 from moving in one axis. The transparent
overlay
haptic device 1 OD also allows for the easy incorporation or motors on the
spline axle
assembly, thus easily making the device 10D an active haptic device. Since
rollers
are incorporated in both axes, the size of the device does not need to be much
larger
than the actual display.
Figure 9 shows a transparent overlay haptic device 10E in accordance with a
fifth embodiment of the present invention. The transparent overlay haptic
device 10E
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keeps the two and one half degrees of freedom and significantly reduces the
size of
the device, without forcing the user to place their finger at a predefined
location.
The transparent overlay haptic device 1 OE includes an overlay 22D which has
a closed surface (e.g. a sphere). The user can continuously move the overlay
22D in
s either the x or y axis without having an edge of the overlay pass over the
display area.
The actuators in the transparent overlay haptic device 10E are the solenoid
brakes
76. An X-Y position sensor is provided if the display 20 is not touch
sensitive. In this
embodiment, there is no need for a homing mechanism for the overlay 22D. The
footprint (i.e. size in the x and y direction) of this embodiment is smaller
than the
1o preferred embodiment, but this embodiment is much deeper (i.e. size in the
z
direction).
Figure 10A shows a top view of a transparent overlay haptic device 10F in
accordance with a sixth embodiment of the present invention. Figure 1 OB shows
a
schematic side view of the transparent overlay haptic device 1 OF. The device
1 OF
15 retains two and one half degrees of freedom and also reduces the size of
the device.
The device 10F has a clear plastic overlay 22E, which wraps around a frame
102 which houses the LCD display 20. The frame 102 is coated by Teflon
(trade-mark). Attached to the clear plastic overlay 22E on the underside of
the frame
102 is a magnet, electromagnet or a series of magnets/electromagnets.~ In
Figures
20 1 OA and 10B, a magnetic ring 106 is attached to the underside of the frame
102. As
the user moves the clear plastic overlay 22E via the finger rest 108, the
attached
mag~ets/electromagnets move relative to the Teflon frame 102. The finger rest
10~
is optional if there is sufficient friction between the user's finger and the
transparent
overlay haptic device 10F. By actuating the electromagnet or by actuating
external
25 electromagnets, haptic effects are applied to the user's finger. For
example, if the
frame 102 is metallic, a braking force may be employed by simply actuating an
attached electromagnet. The transparent overlay haptic device 10F can be
augmented with a homing device to return the finger rest to a predefined
position. The
transparent overlay haptic device 1 OF has the potential to be compact and
versatile.
The position sensor 26 of Figure 1 is now described in detail. An absolute
position sensor and/or a relative position sensor may be employed as the
position
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sensor 26.
The absolute position sensor is described in detail. The absolute position
sensor provides the absolute position of the user's finger. The touch
sensitive LCD
falls into this category. Figure 11 shows an alternate absolute position
sensing
s mechanism. The absolute position sensor of Figure 11 includes an array of
photo-diodes 110 and photo sensors (or detectors) 112 around the outside of
the
display 20. In the absolute position sensor of Figure 11, the photo-sensor
output is
monitored. When the user's finger interrupts the beam of light from the photo-
diodes
110, the interruption is monitored by the sensors 114 and 116 within the
sensors 112.
1o Thus, the x and y positions of the user's finger are obtained. Some
encoders and
potentiometers also measure absolute position and may be used.
The relative position sensor is described in detail. The relative position
sensor
measures the change in position. Examples of sensors that fall into this
category are
optical sensors (e.g, those used in optical mice), encoders on rollers, and
15 potentiometers on rollers. While these sensors may be less expensive and
simpler in
design, they require a calibration to be perFormed to determine a home
position. All
measurements are then taken relative to the determined home position.
As described above, a LCD may be provided to the transparent overlay haptic
device 10. However, any other display technologies can als~ be used. For
e~zample,
o a Cathode Ray Tube (CRT) display, a plasma display, a projection display, or
a Lighfi
Emitting Diode (LED) display are applicable.
As described above, the transparent overlay haptic device 10 can be made
active with the addition of motors, or other active devices (e.g. solenoids,
shape
memory alloys, pneumatics, hydraulics). With the addition of the active
components,
25 the homing mechanism can also be removed since the active actuator can
drive the
overlay to the home position after the user removes their finger from the
device.
A transparent overlay haptic device, which is similar to the device 1 OD, can
be
used to eliminate the requirement that the user always starts from a home
position.
To accomplish this, the device is made active with the addition of motors to
drive the
3o spline axles. The position sensor 26 is accomplished with an array of photo-
diodes
and photo-sensors, such as the position sensor of Figure 11. The position
sensor is
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14
placed far enough from the display 20 so that as the user's finger approaches
the
display 20, the position is obtained and the controller 28 drives the motor
such that
the divot 80 is placed just below the user's finger just before contact is
made with the
display 20. Once the user's finger is on the divot 80, haptic effects can be
felt by
actively driving the motors.
The braking schemes of Figures 3A-3B uses push rod braking schemes.
However, alternate braking schemes can be employed, such as disc braking,
locking
pin brakes, eddy current brakes, or other mechanical braking mechanisms.
In each of the above embodiments, the user is allowed to initially place their
1o finger at any starting point within the display area. An alternate approach
may be
applicable, which makes the user always place their finger at a pre-defined
initial
position. This would remove the requirement for calibration of the relative
position
sensor, since the pre-defined initial position would be the home position. The
initial,
pre-defined position may be marleed with a dimple or rougher texture on the
overlay
22.
According to the embodiment of the present inventions, the main advantages
include, but are not limited to the following:
a) Haptic effects are provided to users without obstructing the view of a
display.
2o b) The passive embodiment of the transparent overlay haptic device is less
expensive than other conventional haptic devices since motors are not
required.
c) The embodiments described can easily be extended to use motors to
implement more complex haptic effects if desired.
d) The user can primarily rely on the sense of touch to navigate through the
2s option selection. This further compliments the phenomena known as muscle
memory
(the phenomena that a user can remember where objects are located in space
after
repetitive motion). This reduces the amount of attention required to perform
other
tasks, and provides less distraction to the main task.
e) The reconfigurability of the transparent overlay haptic device allows for
so intuitive design of the user interface. For example, for adjustment of the
mirrors in a
vehicle, it may be more intuitive to use the knob as a slider instead or using
the
CA 02518914 2005-09-13
WO 2004/081776 PCT/CA2004/000383
rotational axis of the knob as an input.
f) The reconfigurability of the transparent overlay haptic device allows for
the
customization of the user interface.
g) If a touch sensitive display is used, then failure of the haptic portion of
the
5 device (e.g. the overlay breaks, the roller gets stuck) does not prevent the
operation
of the device, since the user can still select options by pressing on the
display 20.
The transparent overlay haptic device 10 and its system 5 can be used in the
automotive industry, aerospace industry, game industry or any other
application
where several control functions are integrated into a single input device and,
for
1o specific reasons (e.g. safety), the user cannot be distracted from other
tasks.
While particular embodiments of the present invention have been shown and
described, changes and modifications may be made to such embodiments without
departing from the true scope of the invention.
