Patent ID: 7163221

Claim:
A retractable step assist for a vehicle, comprising: a step member having a step deck with an upper stepping surface, said step deck movable between a retracted position and a deployed position downward and outboard from said retracted position; an extendable support assembly connectable with respect to an underside of the vehicle so as to extend said step deck downward and outward from the underside of the vehicle in the deployed position; an electrically activated actuator mechanically connected to said extendible support assembly to automatically position said extendible support assembly and said step deck; an optical fiber comprising an inner core and an outer cladding, said outer cladding at least partially surrounding said inner core, said optical fiber having transmission properties that vary when pressure is applied to said optical fiber, said optical fiber disposable on a lower body portion of said vehicle; a light source having an optical output optically connected to said optical fiber so as to couple light output by said light source into said core of said optical fiber such that said light propagates through said optical fiber; a light sensitive optical detector optically coupled to said core of said optical fiber to measure the intensity of said light from said light source propagating through said optical fiber, said intensity measured by said optical detector varying when pressure is applied to said optical fiber, said optical detector having an electrical output dependent on said measured intensity and indicative of said pressure applied; and an electrically activated safety electrically connected to said electrical output of said optical detector, said electrically activated safety terminating retracting motion of said step member when said optical fiber senses pressure from an object pinched between said step deck and said lower body portion.