Accession Number : ADD008937

Title :   Ambulator Control Circuitry.

Descriptive Note : Patent,


Personal Author(s) : Garrett,Robert A ; Silva,John ; Allen,Craig R

Report Date : 18 Aug 1981

Pagination or Media Count : 7

Abstract : This patent discloses control circuitry for producing signals to control motors which propel a mobile platform for a standing paraplegic. Logic circuits connect a 3-axis joy stick controller to four permanent magnet DC motors mounted on the platform such that the platform follows in the direction of the displacement of the joy stick. The joy stick outputs are taken as inputs to several differential amplifiers. Each of a plurality of velocity servo amplifiers receives one input signal from the differential amplifier output and another from a tachometer feedback signal derived from each motor. Comparators receive the velocity servo amplifier outputs as well as a triangular wave input. Each comparator comprises a pulse width modulator which generates pulse outputs whose duty cycle is a function of the voltage inputs to each comparator. the comparator outputs then control motor rotation such that the platform moves in the direction of displacement of the joy stick.

Descriptors :   *Patents, *Control systems, *Servomechanisms, Platforms, Control sticks, Logic circuits, Electric motors, Circuit analysis, Comparators

Subject Categories : Machinery and Tools

Distribution Statement : APPROVED FOR PUBLIC RELEASE