U.S. patent application number 10/356407 was filed with the patent office on 2004-04-22 for apparatus system and method for adapting a scaled vehicle remote controller for use with an enhanced controller.
Invention is credited to Bonilla, Victor G., McCabe, James W..
Application Number | 20040077284 10/356407 |
Document ID | / |
Family ID | 32096837 |
Filed Date | 2004-04-22 |
United States Patent
Application |
20040077284 |
Kind Code |
A1 |
Bonilla, Victor G. ; et
al. |
April 22, 2004 |
Apparatus system and method for adapting a scaled vehicle remote
controller for use with an enhanced controller
Abstract
A method, apparatus, and system are disclosed for adapting an
existing scaled vehicle remote controller for use with an enhanced
controller. An enhanced controller modifies control signals to
conform to the response features of an existing controller. The
modified control signal is transmitted to an original remote
controller and broadcast to a scaled vehicle. The enhanced control
system can control the scaled vehicle with no changes to the
vehicle and only modest changes to the original vehicle controller.
The present invention allows existing remote control vehicles to be
used in more sophisticated competitions and driven using enhanced
operational environments.
Inventors: |
Bonilla, Victor G.;
(Scottsdale, AZ) ; McCabe, James W.; (Scottsdale,
AZ) |
Correspondence
Address: |
KUNZLER & ASSOCIATES
8 EAST BROADWAY
SALT LAKE CITY
UT
84111
US
|
Family ID: |
32096837 |
Appl. No.: |
10/356407 |
Filed: |
January 31, 2003 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
|
|
60353642 |
Jan 31, 2002 |
|
|
|
60374440 |
Apr 22, 2002 |
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Current U.S.
Class: |
446/454 |
Current CPC
Class: |
A63H 30/04 20130101 |
Class at
Publication: |
446/454 |
International
Class: |
A63H 030/00 |
Claims
What is claimed is:
1. A method for adapting a remote controller of a scaled vehicle
for use with an enhanced controller, the method comprising:
providing a remote controller for remotely controlling the scaled
vehicle, the remote controller comprising a transducer and a
transmitter; connecting an enhanced controller to the remote
controller transmitter; and transmitting a control signal to the
scaled vehicle.
2. The method of claim 1, further comprising modifying a control
signal of the enhanced controller to conform to an operating
parameter of the remote controller.
3. The method of claim 1, further comprising overriding the control
signal from the enhanced controller with a track marshal control
signal.
4. The method of claim 3, further comprising transmitting the track
marshal control signal to the scaled vehicle.
5. The method of claim 1, further comprising modifying a control
signal of the enhanced controller to change a maneuvering
characteristic of the scaled vehicle.
6. A method for adapting a remote controller of a scaled vehicle
for use with an enhanced controller, the method comprising:
providing a remote controller for remotely controlling the scaled
vehicle, the remote controller comprising a transducer and a
transmitter; connecting an enhanced controller to the remote
controller transmitter; transmitting a control signal to the scaled
vehicle; modifying a control signal of the enhanced controller to
conform to an operating parameter of the remote controller; and
modifying a control signal of the enhanced controller to change a
maneuvering characteristic of the scaled vehicle.
7. The method of claim 6, further comprising overriding the control
signal from the enhanced controller with a track marshal control
signal.
8. The method of claim 7, further comprising transmitting the track
marshal control signal to the scaled vehicle.
9. An apparatus for adapting a remote controller of a scaled
vehicle for use with an enhanced controller, the apparatus
comprising: a connection circuit connected to the remote
controller; the connection circuit configured to receive a control
signal from the enhanced controller; and a transmitter configured
to transmit the control signal to the scaled vehicle.
10. The apparatus of claim 9, wherein the connection circuit is
further configured to modify the control signal from the enhanced
controller to conform to an operational parameter of the remote
controller.
11. A system for adapting a remote controller of a scaled vehicle
for use with an enhanced controller, the system comprising: the
remote controller configured to receive a control signal from the
enhanced controller and transmit the control signal to the scaled
vehicle; and the enhanced controller configured to receive a a
maneuvering feedback response from the scaled vehicle and
communicate the maneuvering feedback response to a user.
12. The system of claim 11, further comprising a control signal
modification module configured to modify a control signal from the
enhanced controller to conform to an operational parameter of the
remote controller.
13. The system of claim 11, further comprising a control signal
modification module configured to modify a control signal from the
enhanced controller to change a maneuvering characteristic of the
scaled vehicle.
14. The system of claim 11, further comprising a video feedback
module configured to communicate a video feedback response to the
enhanced controller.
15. The system of claim 11, further comprising a force feedback
module configured to communicate a force feedback response to the
enhanced controller.
16. The system of claim 11, further comprising a motion feedback
module configured to communicate a motion feedback response to the
enhanced controller.
17. The system of claim 11, further comprising an audio feedback
module configured to communicate a audio feedback response to the
enhanced controller.
18. The system of claim 11, further comprising a tactile feedback
module configured to communicate a tactile feedback response to the
enhanced controller.
19. The system of claim 11, further comprising an olfactory module
configured to communicate an olfactory feedback response to the
enhanced controller.
20. An apparatus for adapting a remote controller of a scaled
vehicle for use with an enhanced controller, the apparatus
comprising: means for generating a control signal with the enhanced
controller; means for communicating the control signal to the
remote controller; and means for transmitting the control signal to
the scaled vehicle.
21. The apparatus of claim 20, the apparatus further comprising
means for overriding a control signal from the enhanced controller
with a track marshal control signal.
22. The apparatus of claim 20, the apparatus further comprising
means for modifying the control signal to change a maneuvering
characteristic of the scaled vehicle.
23. The apparatus of claim 20, the apparatus further comprising
means for communicating a maneuvering feedback response to a
user.
24. A computer readable storage medium comprising computer readable
program code configured to carry out a method for adapting a remote
controller of a scaled vehicle for use with an enhanced controller,
the method comprising: receiving a control signal from the enhanced
controller; modifying the control signal to conform to an
operational parameter of the remote controller; and transmitting
the control signal to the scaled vehicle.
25. The computer readable storage medium of claim 24, wherein the
method further comprises overriding the control signal from the
enhanced controller with a track marshal control signal.
26. The computer readable storage medium of claim 24, wherein the
method further comprises modifying the control signal of the
enhanced controller to change a maneuvering characteristic of the
scaled vehicle.
Description
RELATED APPLICATIONS
[0001] This application is a Continuation-In-Part of and claims
priority to U.S. Provisional Patent Application Serial No.
60/353,642, filed on Jan. 31, 2002 for Racing Visions, L.L.C., and
for Provisional Patent Application Serial No. 60/374,440 filed on
Apr. 22, 2002 for Racing Visions, L.L.C.
BACKGROUND OF THE INVENTION
[0002] 1. The Field of the Invention
[0003] The invention relates to controlling a scaled vehicle using
an alternate remote control system. Specifically, the invention
relates to controlling a scaled vehicle by interfacing an
alternate, enhanced remote control system to the vehicle's original
remote controller.
[0004] 2. The Relevant Art
[0005] Hobbyists own hundreds of thousands of scaled, remote
control vehicles. Users can maneuver or race these vehicles
individually using a vehicle's original controller systems.
However, there is a growing demand to employ scaled vehicles in
increasingly sophisticated events that exceed the capabilities of
the original controllers. Remote scaled-vehicle competitions
require increased organization and control of drivers, many of whom
are young or novice competitors. A track marshal may need to
temporarily control vehicles in order to position them for the
start of a race, resolve accidents or mechanical failures, and
maintain order on the track.
[0006] There is a growing interest in driving remote control
vehicles using advanced maneuvering and feedback systems. However,
advanced features, services, and functionality cannot be made
available to existing scaled vehicle users because their vehicles
use a variety of incompatible controllers. Currently, enhanced
remote control systems must be closely integrated with a racing or
driving venue. Racing venue operators cannot economically supply
the variety of expensive enhanced remote control systems needed to
allow all users operate their vehicles with a venue's added
features, services, and functionality. Without access to advanced
remote control systems, vehicles cannot be controlled in centrally
managed and directed events and competitions. Users also cannot
take advantage of advanced driving and racing services such as
remote vision, driving simulator cockpits and controls, or computer
enhancement of a user's driving.
[0007] What is needed are methods, apparatus, and systems for
allowing more sophisticated remote vehicle controllers to control
and operate existing scaled vehicles by adapting a vehicle's
original remote controller for use with an alternate controller. In
particular, what is needed is a method, apparatus, and system for
interfacing an enhanced remote control system with the transmitter
of an existing remote controller, thereby allowing the enhanced
remote control system to manipulate a vehicle with modest
modifications to the original controller and without changes to the
vehicle.
BRIEF SUMMARY OF THE INVENTION
[0008] The various elements of the present invention have been
developed in response to the present state of the art, and in
particular, in response to the problems and needs in the art that
have not yet been fully solved by currently available scaled remote
vehicles. Accordingly, the present invention provides an improved
apparatus, method, and system for maneuvering existing scaled
vehicles with an enhanced remote control system. In one aspect of
the present invention, a method of interfacing an enhanced
controller of a remote control system to an original remote
controller of an existing scaled vehicle is presented. A user
controls a scaled vehicle through an enhanced controller while
using the additional features, services, and functionality of the
remote control system.
[0009] In another aspect of the present invention, an apparatus is
also presented and provided with an enhanced controller that
converts a user's control inputs into a control signal. The
enhanced controller also modifies the control signal to match the
operating parameters of the original remote controller and the
scaled vehicle. The apparatus is further provided with a connection
to an original remote controller. The connection supplies the
enhanced controller's control signal to the remote controller's
transmitter. The apparatus allows a user to control a scaled
vehicle with an alternate enhanced controller through the vehicle's
original remote controller.
[0010] Various elements of the present invention are combined into
a system for maneuvering a scaled vehicle. The system provides a
user with an enhanced controller for generating a control signal.
The system substitutes the enhanced controller's control signal for
the control signal of the original scaled vehicle remote
controller. The system employs the vehicle's original remote
controller to broadcast the enhanced controller's control signal to
the scaled vehicle.
[0011] The present invention facilitates a user controlling an
existing scaled vehicle with an enhanced remote vehicle controller
system. The present invention may also support an advanced
operational environment, including video, audio, motion, and/or
force feedback to the user. In one embodiment, the present
invention facilitates a track marshal taking control of an existing
scaled vehicle to manage recreational and racing events. The
present invention further supports modification of a user's driving
commands to improve or change maneuvering performance. These and
other features and advantages of the present invention will become
more fully apparent from the following description and appended
claims, or may be learned by the practice of the invention as set
forth hereinafter.
BRIEF DESCRIPTION OF THE DRAWINGS
[0012] In order that the manner in which the advantages and objects
of the invention are obtained will be readily understood, a more
particular description of the invention briefly described above
will be rendered by reference to specific embodiments thereof,
which are illustrated in the appended drawings. Understanding that
these drawings depict only typical embodiments of the invention and
are not therefore to be considered to be limiting of its scope, the
invention will be described and explained with additional
specificity and detail through the use of the accompanying drawings
in which:
[0013] FIG. 1 is a block diagram illustrating one embodiment of a
remote control system in accordance with the prior art;
[0014] FIG. 2 is a block diagram illustrating one embodiment of an
enhanced controller/remote controller system of the present
invention;
[0015] FIG. 3 is a block diagram illustrating one embodiment of a
remote control system of the present invention;
[0016] FIG. 4 is a block diagram illustrating one embodiment of an
enhanced controller of the present invention;
[0017] FIG. 5 is a flow chart illustrating one embodiment of a
remote control method in accordance with the prior art; and
[0018] FIG. 6 is a flow chart illustrating one embodiment of a
remote control method in accordance with the present invention.
DETAILED DESCRIPTION OF THE INVENTION
[0019] Many of the functional units described in this specification
have been labeled as modules, in order to more particularly
emphasize their implementation independence. For example, a module
may be implemented as a hardware circuit comprising custom VLSI
circuits or gate arrays, off-the-shelf semiconductors such as logic
chips, transistors, or other discrete components. A module may also
be implemented in programmable hardware devices such as field
programmable gate arrays, programmable array logic, programmable
logic devices or the like.
[0020] Modules may also be implemented in software for execution by
various types of processors. An identified module of executable
code may, for instance, comprise one or more physical or logical
blocks of computer instructions which may, for instance, be
organized as an object, procedure, or function. Nevertheless, the
executables of an identified module need not be physically located
together, but may comprise disparate instructions stored in
different locations which, when joined logically together, comprise
the module and achieve the stated purpose for the module.
[0021] Indeed, a module of executable code could be a single
instruction, or many instructions, and may even be distributed over
several different code segments, among different programs, and
across several memory devices. Similarly, operational data may be
identified and illustrated herein within modules, and may be
embodied in any suitable form viola 20 and organized within any
suitable type of data structure. The operational data may be
collected as a single data set, or may be distributed over
different locations including over different storage devices, and
may exist, at least partially, merely as electronic signals on a
system or network.
[0022] Referring to FIG. 1, a remote control system 100 is
illustrated that is representative of the environment wherein the
present invention may be deployed. The remote control system 100
allows a user to maneuver a scaled vehicle 150. The depicted remote
control system 100 includes a remote controller 110 and a scaled
vehicle 150. The remote controller 110 includes a mechanical
control input module 120, a transducer module 130, an encoder
module 135, and a transmitter module 140. The scaled vehicle 150
includes a receiver module 160, a decoder module 165 and an
actuator module 170.
[0023] In one embodiment, a user may maneuver the scaled vehicle
150 by manipulating the mechanical control input module 120. The
transducer module 130 converts a mechanical control input into an
electrical control signal. The encoder module 135 encodes the
control signal. The transmitter module 140 broadcasts the control
signal. The receiver module 160 of the scaled vehicle 150 receives
the control signal. The decoder module 165 decodes the control
signal. In response to control signal, the actuator module 170
manipulates an actuator, such as a steering mechanism, of the
scaled vehicle 150. Manipulating an actuator of the scaled vehicle
150 allows the user to maneuver the scaled vehicle 150.
[0024] FIG. 2 is a schematic block diagram illustrating one
embodiment of an enhanced controller/remote controller system 200
of the present invention. The depicted system 200 includes an
enhanced controller module 210 and a marshal controller module 230.
The depicted system 200 further includes a remote controller 110
with a mechanical control input module 120, a transducer module
130, an encoder module 135, a control circuit connection module
220, and a transmitter module 140.
[0025] The system 200 maneuvers a scaled vehicle 150 with an
enhanced controller module 210 configured to introduce a control
signal into the original remote controller 110 of the scaled
vehicle 150. In this way, the enhanced controller module 210
provides a control interface for maneuvering a scaled vehicle 150.
Control interfaces may be items commonly found in a standard
vehicle 150 including a steering wheel, handlebars, gas pedal,
brake, clutch, stick shift, speedometers, or gauges. Control
interfaces may alsoincludejoysticks, game pads, and pointing
devices. The enhanced controller module 210 converts an input to a
control interface into a control signal.
[0026] The enhanced control module 210 connects to an original
remote controller 110 of a scaled vehicle 150 through a control
circuit connection module 220. The control circuit connection
module 220 replaces a control signal that is input into a remote
controller's 110 encoder module 135. The control signal is
broadcast to a scaled vehicle 150 by the transmitter module 140.
The mechanical control input module 120 and the transducer module
130 are not used by the remote control system 200.
[0027] The marshal controller module 230 provides means for a track
marshal to maneuver a scaled vehicle 150. Through the marshal
controller module 230 a track marshal may override a control signal
of the enhanced control module 210. In one embodiment, the marshal
controller module 230 may facilitate positioning or removal of a
scaled vehicle 150 in a racing event.
[0028] FIG. 3 is a block diagram illustrating one embodiment of an
enhanced remote control system 300 of the present invention. The
remote control system 300 provides a plurality of feedback, race
management, and performance enhancement features to a user
controlling a scaled vehicle 150 using an original remote
controller 110. The depicted system 300 includes a remote
controller 110, an enhanced controller 210, a control signal
modification module 310, a video feedback module 320, a motion
feedback module 330, a force feedback module 340, an olfactory
feedback module 350, an audio feedback module 360, a tactile
feedback module 370, and a track management module 380.
[0029] The enhanced controller 210 generates a control signal from
a user control input. The control signal is broadcast to a scaled
vehicle 150 through the remote controller 110 as illustrated in
FIG. 2. Control inputs may come from a variety of devices including
steering wheels, gear-shift levers, gas pedals, brake pedals,
handle bars, joy sticks, control yokes, control levers, or game
controllers.
[0030] The control signal modification module 310 provides services
for modifying a control signal from the enhanced control module
210. The control signal modification module 310 modifies the
control signal to conform to a remote controller 110 of an existing
scaled vehicle 150.
[0031] In one embodiment, the control signal modification module
310 improves the maneuvering performance of a scaled vehicle 150.
The control signal modification module 310 may slow the response of
the control signal to control inputs, improving the maneuvering
performance of novice drivers. The control signal modification
module 310 may also simulate the maneuvering response of a target
vehicle.
[0032] The video feedback module 320 in one embodiment provides
services for displaying a video image. The image may be provided
from at least one video camera 106 mounted on a scaled vehicle 150.
In an alternate embodiment, the video image is provided from at
least one video camera mounted adjacent a track. The video image
may also be simulated from the positions of a scaled vehicle
150.
[0033] The motion feedback module 330 in one embodiment provides a
user with a sensation of the motion of a scaled vehicle 150 by
modifying the physical position of the user in from an original
position. For example, small motions of a user's driving cockpit
may simulate acceleration, cornering, and braking. The force
feedback module 340 provides a user with force feedback in a
control interface of the enhanced controller 210. For example, a
steering wheel control interface may resist being turned by a user
or a clutch may vibrate or resist being released. Similarly, a
gear-shift lever may also simulate grinding if the user attempts to
shift gears incorrectly.
[0034] The olfactory feedback module 350 may in one embodiment
provide a user with a smell or scent associated with a racing
experience. The olfactory feedback module 350 may introduce a
subtle scent resembling high-octane fuel. In a similar manner, the
audio feedback module 360 may provide a user with audio feedback
similar to that of a racing experience. For example, the audio
feedback module 360 may provide a user with audio feedback from
microphones mounted on the scaled vehicle 150. In an alternate
embodiment, the audio feedback module 360 may provide simulated
racing sounds based on the status of control inputs. For example,
the audio feedback module 360 may be configured to provide the
sound of squealing tires while the user initiates a turn, or the
sound of an accelerating engine as the user depresses an
accelerator pedal. The tactile feedback module 370 in one
embodiment provides a user with the tactile sensations associated
with maneuvering a vehicle. A stream of air may simulate wind
striking a driver. The air stream may increase or decrease
depending on the speed of the scaled vehicle 150.
[0035] The track management module 380 in one embodiment provides
services for a track marshal to control a scaled vehicle 150
independent of a user's enhanced controller 210. Allowing a track
marshal to independently control a scaled vehicle 150 facilitates
racing or orderly track use. A track marshal may use the track
management module 380 to correctly position all scaled vehicles 150
for the start of a race. A track marshal may also use the track
management module 380 to take control of a vehicle 150 that is
behaving erratically and remove the vehicle 150 from the track.
[0036] FIG. 4 is a block diagram illustrating one embodiment of an
enhanced controller 600 of the present invention. The enhanced
controller 400 converts a user control input for maneuvering a
scaled vehicle 150 into a control signal capable of driving the
transmitter 140 of the vehicle's original remote controller 110.
The enhanced controller 400 is substantially similar to the
enhanced controller 210 of FIG. 2 and includes a mechanical control
input module 410, a transducer module 420, an analog to digital
module 430, a digital processing module 440, and a digital to
analog module 450.
[0037] The illustrated mechanical control input module 410 accepts
a user control input. The mechanical control input module 410 may
include a steering wheel, a control lever, a handlebar assembly, an
accelerator pedal, a brake, a clutch, a gear-shift lever, or a
joystick. The transducer module 420 converts a mechanical motion of
the mechanical control input module 410 into an analog electrical
signal. The analog to digital module 430 converts the analog
electrical signal of the transducer module 420 into a digital
control signal.
[0038] The digital processing module 640 in one embodiment
processes a digital control signal to conform to a remote
controller 110 of an existing scaled vehicle 150. The digital
processing module 440 may modify the digital control signal to
improve the maneuvering performance of the user and scaled vehicle
150. For example, the digital processing module 440 may slow the
response of a digital control signal for a novice user so that the
scaled vehicle 150 is more easily maneuvered. The digital
processing module 440 may also modify control signals simulating
the response of a target vehicle. In one instance, a track marshal
may override the digital control signal with an alternate digital
control signal, allowing the track marshal to take control of a
scaled vehicle 150.
[0039] The digital to analog module 450 converts the processed
digital control signal into an analog signal. The analog signal is
provided to the control circuit connection module 220 as shown in
FIG. 2.
[0040] FIG. 5 is a flow chart illustrating one embodiment of a
remote control method 500 in accordance with the prior art. The
remote control method 500 facilitates maneuvering of a scaled
vehicle 150 by a user. Although for purposes of clarity the steps
of the remote control method 500 are depicted in a certain
sequential order, execution of the steps within an actual system,
such as the system 100 of FIG. 1, may be conducted in parallel and
not necessarily in the depicted order.
[0041] The depicted remote control method 500 includes a user
inputs step 510, a mechanical to electrical step 520, an encode
control signal step 525, a control signal transmission step 530, a
control signal receiving step 540, a decode control signal step
545, a control actuation step 550, and an end step 560. The control
inputs step 510 accepts a user control input for maneuvering a
scaled vehicle 150. Control inputs are accepted from a steering
wheel, a control lever, a gear-shift lever, an accelerator pedal, a
brake pedal, a handle bar, a control lever, or a joystick. The
mechanical to electrical step 520 converts the user's mechanical
control input motion into an control signal. The encode control
signal step 535 encodes the control signal. The control signal
transmission step 530 broadcasts the control signal from a remote
controller 110. The control signal receiving step 540 receives a
control signal at a scaled vehicle 150. The decode control signal
step 545 decodes the control signal. The control actuation step 550
modifies the position of actuators on a scaled vehicle 150
according the parameters of the control signal. The change in
actuator position controls the motion of the scaled vehicle 150,
allowing the user to maneuver the scaled vehicle 150. The method
500 then terminates at the end step 560.
[0042] FIG. 6 is a flow chart illustrating one embodiment of a
remote control method 600 of the present invention. The remote
control method 600 facilitates maneuvering of a scaled vehicle 150
by a user through an enhanced remote control system 300. Although
for purposes of clarity the steps of the remote control method 600
are depicted in a certain sequential order, execution of the steps
within an actual system, such as the system 200 of FIG. 2, may be
conducted in parallel and not necessarily in the depicted
order.
[0043] The depicted remote control method 600 includes a user
inputs step 610, a mechanical to digital step 620, a digital
processing step 630, and a digital to analog step 640. The control
method 600 further includes the encode control signal step 525, the
control signal transmission step 530, the control signal receiving
step 540, the decode control signal step 545, the control actuation
step 550 of the remote control method 500 of FIG. 5, and an end
step 650.
[0044] The user inputs step 610 accepts a user input for
maneuvering a scaled vehicle 150. The mechanical to digital step
620 converts the user input into a digital control signal. The
digital processing step 630 processes the digital control signal.
For example, the digital processing step 630 modifies the digital
control signal to conform with an original remote controller 110 of
a target scaled vehicle 150. The digital processing step 630 may
also modify the digital control signal to improve the maneuvering
performance of the user and scaled vehicle 150. The digital
processing step 630 may further modify the digital control signal
to simulate the response of a target vehicle. In one embodiment, a
track marshal may override the digital control signal with an
alternate digital control signal, allowing the track marshal to
take control of a scaled vehicle 150.
[0045] The digital to analog step 640 converts a digital control
signal into an analog control signal. The encode control signal
step 525 encodes the control. The control signal transmission step
530 broadcasts the control signal using the original remote
controller 110 of the scaled vehicle 150. The control signal
receiving step 540 receives a control signal at a scaled vehicle
150. The decode control signal step 545 decodes the control signal.
The control actuation step 550 modifies the position of actuators
on a scaled vehicle 150 according the parameters of the control
signal. The change in actuator position controls the motion of the
scaled vehicle 150, allowing the user to maneuver the scaled
vehicle 150. The method 600 then terminates at the end step
650.
[0046] The present invention allows a user to maneuver an existing
scaled vehicle 150 with an enhanced controller/remote control
system 200 that supports additional features, services, and
functionality. In particular, the present invention supports the
maneuvering of an existing scaled vehicle with an enhanced remote
control system 300 with improved control inputs, added feedback
options, and provided with capabilities to manage a sophisticated
racing event.
[0047] The present invention may be embodied in other specific
forms without departing from its spirit or essential
characteristics. The described embodiments are to be considered in
all respects only as illustrative and not restrictive. The scope of
the invention is, therefore, indicated by the appended claims
rather than by the foregoing description. All changes which come
within the meaning and range of equivalency of the claims are to be
embraced within their scope.
* * * * *