Abstract: A system for enabling a vehicle operator to control the speed or rate of raising and lowering of a powered lift window. The actuator or switch includes a pressure responsive variable impedance device comprising a variable resistance in one embodiment and a variable capacitance in another embodiment. Increasing force directly on the variable impedance device by the user's finger or an actuator decreases the impedance which is sensed by a voltage divider which outputs a voltage which increases with increasing force. This latter voltage is compared with the output of a triangle wave oscillator and the output of the comparator is a pulse width modulated signal with pulse-width proportional to applied force. The pulses are applied to a power device (Mosfet) which modulates the duty cycle (%) of the current to the window lift mechanism drive motor to give variable motor speed.

Abstract: A multiple channel parallel transfer digital disk recorder is used to record digitized circular video images at the video frame rate. The digital pixel values for each image frame are written onto successive pages of a disk buffer memory (DBM) under video frame timing and are read from memory and written on disk under disk timing. When the last page image of the DBM is reached readout is switched back to the first page which is now filled with a frame of image data. Reading image data from disk and writing into successive pages of the DBM is done similarly. Only DBM locations containing pixels representative of actual image data within the circular boundaries of the image are addressed when reading from DBM and writing on disk and when reading from disk and writing onto DBM. Adjacent pixels in the image having predetermined bit lengths are written on disk with their bits in series.