Geoff R. Fernie, PhD, PEng, is Director, Centre for Studies in Aging, and Director, Research Program in Aging, Sunnybrook Health Science Centre, Toronto, Ontario; Professor, Departments of Surgery, Occupational Therapy, Physical Therapy, and Mechanical Engineering, University of Toronto

Gerald T. Griggs is Professional Engineering Officer, Centre for Studies in Aging, Sunnybrook Health Science Centre, Toronto, Ontario

Pamela J. Holliday, MSc, PT, is Research Associate, Centre for Studies in Aging, Sunnybrook Health Science Centre, 2075 Bayview Avenue, Toronto, Ontario M4N 3M5 and Research Associate, Department of Physical Therapy, University of Toronto

Anne Topper, MASc, is Professional Engineering Officer, Centre for Studies in Aging, Sunnybrook Health Science Centre, Toronto, Ontario