A device which functions as a conventional wheelchair, a dynamic seating device, a stander and a hands-free walker. The imaging system, which can include a linescan sensor, measures the height of an object on a component as well as the coplanarity of object features by viewing the object features from a plurality of view angles. The clip is configured such that the first attachment member is insertable into the first recess for snap-fit engagement with the clip to retain the first trim cover portion with respect to the cushion. The device of the preferred embodiment is comprised of a sound generation element 12 such as pliable material, and may include a means of attachment element 14. Further, the parasitic diode of the MOS transistor functions as a static protection diode.