NDLI: Step climbing capability of a 4WD omnidirectional wheelchair

Content Provider	IEEE Xplore Digital Library
Author	Wada, M.
Copyright Year	2008
Description	Author affiliation: Dept. of Human-Robot., Saitama Inst. of Technol., Fukaya (Wada, M.)
Abstract	This paper presents analysis and experiments of a 4WD omnidirectional wheelchair for climbing a high step. For enhancing the mobility and maneuverability of standard wheelchairs, a new type of omnidirectional mobile platform with four-wheel drive (4WD) mechanism is introduced. The mobile platform equips four wheels, two omni-wheels in front and two normal tires in rear. The normal wheel and the omni-wheel, mounted on the same side of the base, are interconnected by belt transmissions to rotate in unison with a drive motor, i.e. a synchro-drive transmission. To rotate a chair at the center of the mobile base about vertical axis, the third motor is installed on the platform. The prototype wheelchair with the proposed 4WD system is capable of moving in any direction and climbing over a high single step. The conventional 4WD system provides enhanced step climb capability. However the maximum step height is restricted by the rear wheels. Namely, front wheels can climb up higher step than the rear wheels although the both wheels are identical in diameter. To clarify the difference between front and rear wheels in the step climb capability, the statics of the 4WD system is analyzed. It is suggested that the reaction of a drive torque cause the front-rear differences and its influence depends on a wheelbase and a vehicle weight distribution ratio between front and rear wheel axes. For varying a vehicle weight distribution ratio, we develop a chair tilting mechanism for the 4WD wheelchair with a linear drive mechanism controlled by a stability algorithm using an inclinometer. To verify the analysis results and availability of the chair tilting mechanism, step climb capabilities of a 4WD wheelchair prototype is tested in experiments. In the experiments, both front and rear wheels of the prototype wheelchair with a human can successfully climb a 90 mm step while the rear wheels fail when the chair tilting system is disabled.
Starting Page	266
Ending Page	272
File Size	1171552
Page Count	7
File Format	PDF
ISBN	9781424420575
DOI	10.1109/IROS.2008.4650920
Language	English
Publisher	Institute of Electrical and Electronics Engineers, Inc. (IEEE)
Publisher Date	2008-09-22
Publisher Place	France
Access Restriction	Subscribed
Rights Holder	Institute of Electrical and Electronics Engineers, Inc. (IEEE)
Subject Keyword	Wheels Wheelchairs Torque Prototypes Mobile communication Jacobian matrices Traction motors
Content Type	Text
Resource Type	Article

Sl.	Authority	Responsibilities	Communication Details
1	Ministry of Education (GoI), Department of Higher Education	Sanctioning Authority	https://www.education.gov.in/ict-initiatives
2	Indian Institute of Technology Kharagpur	Host Institute of the Project: The host institute of the project is responsible for providing infrastructure support and hosting the project	https://www.iitkgp.ac.in
3	National Digital Library of India Office, Indian Institute of Technology Kharagpur	The administrative and infrastructural headquarters of the project	Dr. B. Sutradhar bsutra@ndl.gov.in
4	Project PI / Joint PI	Principal Investigator and Joint Principal Investigators of the project	Dr. B. Sutradhar bsutra@ndl.gov.in Prof. Saswat Chakrabarti will be added soon
5	Website/Portal (Helpdesk)	Queries regarding NDLI and its services	support@ndl.gov.in
6	Contents and Copyright Issues	Queries related to content curation and copyright issues	content@ndl.gov.in
7	National Digital Library of India Club (NDLI Club)	Queries related to NDLI Club formation, support, user awareness program, seminar/symposium, collaboration, social media, promotion, and outreach	clubsupport@ndl.gov.in
8	Digital Preservation Centre (DPC)	Assistance with digitizing and archiving copyright-free printed books	dpc@ndl.gov.in
9	IDR Setup or Support	Queries related to establishment and support of Institutional Digital Repository (IDR) and IDR workshops	idr@ndl.gov.in