RESNA 28th Annual Conference - Atlanta, Georgia
SPAM Power-Assist and Emergency Stop Test
Graph 1 depicts the digital values of pushrim torque signals, wheel speed signals from encoders, and PWM signals that were sent to motors of one drive wheel, when the SPAM is propelled down and up a slight slope (about 5 o gradient). There were three major strokes to propel the SPAM down the slope for about 30 meters, and about ten strokes for climbing up the same distance. The wheelchair was stopped by applying a reverse torque on the pushrim at the end of the down and up climbing periods, respectively. At the end of the trial, the stop button was triggered for an emergency stop.