Communications Project

Document Type:Dissertation
Name:Laura L. Clark
Title:Design and Testing of a Quick-Connect Wheelchair Power Add-On Unit
Degree:Doctor of Philosophy
Department:Industrial and Systems Engineering
Committee Chair: John G. Casali
Committee Members:Robert C. Williges
Beverly A. Williges
Patrick C. Koelling
L. Thompson Hanes
Keywords:power attachment, usability testing, electric wheelchair, product evaluation
Date of defense:December 4, 1997
Availability:Release the entire work for Virginia Tech access only.
After one year release worldwide only with written permission of the student and the advisory committee chair.


A quick-connect wheelchair power add-on unit (PAU) has been developed at the Human Factors Engineering Center of Virginia Tech. The objective of the new invention is to provide an inexpensive, highly portable product which can quickly convert a manual wheelchair into a power-operated wheelchair. This dissertation details the three year research and design effort to develop the new wheelchair PAU. Results are presented from a series of evaluations conducted to identify performance and user-interaction characteristics of the PAU. Interpretation of the results provides a prioritized list of identified design deficiencies along with wheelchair expert and design team suggestions for the next generation of design alterations.

The three evaluations conducted with the second generation PAU prototype include a series of wheelchair expert interviews, a PAU performance evaluation, and a usability evaluation which utilized wheelchair operators as subjects. Also included in the dissertation is an explanation of the need for a new PAU, a description of the most recent design iteration, a literature review containing information about the history of wheelchairs, the condition of the current PAU market, and an analysis of wheelchair PAU consumers.

The new invention was conceived and patented by Dr. John G. Casali of the Industrial and Systems Engineering (ISE) Department at Virginia Tech. This research was supported jointly by Southwestern Applied Technologies, L. C., of Roanoke, Virginia and Virginia's Center for Innovative Technology in Herndon, Virginia.

List of Attached Files

a10_steer_bar_cover.pdf a11_handle.pdf a12_slipring_cover.pdf
a13_inner_tube.pdf a14_outer_tube.pdf a15_crossbar.pdf
a16_poppits.pdf a17_finger_grip.pdf a18_col_cross_block1.pdf
a19_col_cross_block3.pdf a20_col_cross_block4.pdf a21_wheel_supp_side.pdf
a22_wheel_supp_top.pdf a23_tube_block.pdf a24_gearbox.pdf
a25_gearbox_cover.pdf a26_motor_cover1.pdf a27_motor_cover2.pdf
a28_motor_1support.pdf a29_motor_2support.pdf a2_spring_housing.pdf
a30_axle_aug.pdf a31_sling_pattern.pdf a3_drivetrain.pdf
a4_sec_block1.pdf a5_sec_block3.pdf a6_sec_block5.pdf
a7_sec_block7.pdf a8_sec_block9.pdf a9_steer_bar.pdf
appendices.pdf b1_manual_chair.pdf conclusion.pdf
contents.pdf design_recommendations.pdf expert_evaluation.pdf
introduction.pdf literature_review.pdf papoose.pdf
performance_evaluation.pdf redpak.pdf sling.pdf
table_10_pre_est.pdf table_11_post_est.pdf table_12_ci.pdf
table_13_co.pdf table_7_timedata.pdf table_8_ci_blank.pdf
table_9_times.pdf table_c1_patent.pdf usability_evaluation.pdf

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