Rolling footwear - a novel ambulatory aid

A pair of prototype roller skates was developed to assist individuals with ambulatory problems by reducing the energy cost of ambulation and improve performance in terms of speed and endurance. Unlike ordinary roller skates, the rear wheels are equipped with a spring loaded brake system that locks the wheels when the user applies enough weight at the heel; for example: while standing still. The brakes are released when the ratio of the load on the rear wheels to the user's body weight, Q, is reduced below the value determined by the selection of the spring. The useful range of Q is estimated to be between 0.275 and 0.325. Prototype roller skates have been built and tested on healthy young volunteers with promising results.