COMPUTER-CONTROLLED POWER WHEELCHAIR NAVIGATION SYSTEM

• US 20080300777A1
• Filed: 05/06/2008
• Published: 12/04/2008
• Est. Priority Date: 07/02/2002
• Status: Abandoned Application

• Current Assignee: US Department of Veterans Affairs (Government of the United States of America), University of Notre DAME Du Lac
• Original Assignee: US Department of Veterans Affairs (Government of the United States of America), University of Notre DAME Du Lac
• Inventors: Skaar, Steven B., Fehr, Linda, Del Castillo, Guillermo
• Application Number:
  US12/115,978
• Publication Number:
  US 20080300777A1
• Time in Patent Office: Days
• US Class Current: 701/200
• CPC Class Codes: A61G 2203/22 for automatically guiding movable devices, e.g. stretchers or wheelchairs in a hospital
• CPC Class Codes: A61G 5/10 Parts, details or accessories
• CPC Class Codes: G01C 21/20 Instruments for performing navigational calculations G01C21/24, G01C21/26 take precedence

Abstract

A wheelchair navigation system for a motorized wheelchair includes dual cameras, proximity sensors, microphones, and rotation sensors for the wheels. Small markers are placed on the walls of a location or room. The navigation system uses the proximity sensors, rotation sensors and cameras in conjunction with the specialized software to determine where objects or impediments are located in the room and thereby redirect the path of the wheelchair so as to avoid such objects. The wheelchair is walked through the marked location thereby ‘teaching’ various paths which are recorded in the computer and recalled later when the wheelchair is in use. The proximity sensor perform sensing operations during performance of the teaching functions for thereby permitting avoidance of wheelchair collision with obstacles during navigation of the wheelchair through a taught trajectory and allowing for close approach of the wheelchair to solid bodies present during performance of the teaching functions.

Claims

1. A wheeled device navigation system comprising:

a motorized wheeled device;

at least one computer having software that performs

navigational functions,

teaching functions, and

obstacle detection;

at least one proximity sensor;

at least one rotation sensor;

at least one cue sensor attached to said wheeled device for sensing cue markers;

at least one cue marker disposable in areas surrounding said wheeled device and configured to be sensed by said cue sensor;

wherein said at least one rotation sensor and said at least one cue sensor are interfaced to said at least one computer which runs the specialized software during performance of said teaching functions, and said at least one proximity sensor performs sensing operations for thereby permitting avoidance of wheeled device collision with obstacles during navigation of said wheeled device through a taught trajectory and allowing for close approach of said wheeled device to solid bodies present during performance of said teaching functions.

2. A wheeled device navigation system according to claim 1, wherein:

said at least one computer has a screen with a visual display.

3. A wheeled device navigation system according to claim 1, wherein:

said computer receives information from said cue sensors, processes said information and determines a path of travel for said wheeled device from such information.

4. A wheeled device navigation system according to claim 1, wherein:

said computer is voice activated.

5. A wheeled device navigation system according to claim 1, wherein:

said computer is manually operated.

6. A wheeled device navigation system comprising:

a motorized wheeled device;

at least one battery removably attached to said wheeled device to power said wheeled device;

a battery charger removably attached to said wheeled device and configured to charge said battery;

a filter-based estimator with interface software for estimating and relaying a trajectory for said wheeled device;

a computer having software that performs navigational functions and teaching functions;

at least one camera;

at least one proximity sensor;

at least one microphone;

at least one rotation sensor for the wheels, said at least one sensor is mounted on the wheeled device; and

a plurality of cue markers capable of being placed on the walls of a specific location,

wherein said at least one proximity sensor performs sensing operations during performance of said teaching functions for thereby permitting avoidance of wheeled device collision with obstacles during navigation of said wheeled device through a taught trajectory and allowing for close approach of said wheeled device to solid bodies present during performance of said teaching functions.

7. A wheeled device navigation system according to claim 6, wherein:

said at least one computer has a screen with a visual display that is visible to a person using the wheeled device.

8. A wheeled device navigation system according to claim 6, wherein:

said computer receives information from said cameras and said sensors, processes said information and determines a path of travel for said wheeled device from such information.

9. A wheeled device navigation system according to claim 6, wherein:

said computer is voice activated.

10. A wheeled device navigation system according to claim 6, wherein:

said computer is manually operated.

11. A method of navigation using a powered wheeled device comprising the steps of:

providing a motorized wheeled device, said wheeled device being powered by at least one onboard battery removably attached to said wheeled device, and a battery charger removably attached to said wheeled device and configured to charge said battery and having dual cameras, proximity sensors, a microphone and rotation sensors for sensing wheel rotation;

providing a filter-based estimator for estimating and relaying a trajectory for said wheeled device with interface software running that is operated on at least one computer including a control system;

providing markers at various locations within a specific area;

teaching at least one path by walking said wheeled device through said at least one path prior to said wheeled device navigation system being used for independent travel, and recording said at least one path in said computer;

sensing said markers and solid bodies with said proximity sensors and said cameras during performance of said teaching for thereby permitting avoidance of wheeled device collision with obstacles during navigation of said wheeled device through a taught trajectory and allowing for close approach of said wheeled device to solid bodies present during performance of said teaching;

providing information about said markers and said solid bodies from said proximity sensors and said cameras to said at least one computer;

operating said software to determine the location of various objects within a location;

creating a path for said wheeled device to avoid said objects with said software; and

directing said wheeled device on said path via said software.

12. A method of navigation using a powered wheeled device according to claim 11, further comprising the step of:

operating said computer via voice control.

13. A method of navigation using a powered wheeled device according to claim 11, further comprising the step of;

operating said computer manually.

14. A method of navigation using a powered wheeled device according to claim 11, further comprising the step of:

establishing ultrasound profiles at various junctures throughout a path during performance of said teaching.

15. A method of navigation using a powered wheeled device according to claim 14, further comprising the step of:

simplifying said profiles in a postprocessed computer event; and

comparing said profiles during tracking through a taught path with current ultrasound sensed profiles.

16. A method of navigation using a powered wheeled device according to claim 15, further comprising the step of:

comparing disparities between said current ultrasound sensed profiles of objects to determine if a configuration of an object close to the taught path has changed since said teaching, and if said configuration has changed by a predetermined threshold, halting said wheeled device.