Figure 14From: Development and analysis of a novel add-on drive mechanism for motorizing a manual wheelchair and its step climbing strategy Experimental results of the mechanism. When the linear actuator was stretched, the active-caster moved to the point C wheelie , so that the front casters could hover above the ground at the height of 100 mm. In contrast, when the linear actuator was shrunk, the active-caster moved to the point C hover and contacted the ground.Back to article page