Patent · US Expired

Digital robot control having an improved pulse width modulator

US4894598A · kind A · utility

29Cited by
24References
24Claims
0Family size

Assignee

Inventor

Key dates

Filing dateAug 5, 1988
Grant dateJan 16, 1990
Priority date
Expiry dateAug 5, 2008

Classification

  • Technology area (CPC G)Physics
  • CPC primaryG05B2219/45083
  • WIPO fieldControl
  • WIPO sectorInstruments

Abstract

A pulse width moduation (PWM) scheme provides for digital implementation of robot control commands. For this purpose, it provides time stabilized current sampling synchronized to the sampling frequency of the position and velocity loops in the robot control. The PWM scheme enables accurate motor current measurement through usage of a single current sense resistor independent of the number of legs in a power amplifier configuration. This scheme permits commercially available, low cost, power blocks to be used for implementation of robot control system power amplifiers. The PWM scheme is cost effectively implemented in a semi-custom large scale integrated (LSI) circuit which provides the digital interface between a torque loop microprocessor and the drive circuitry for the power handling devices used to apply voltage to the robot axis actuator. Interface and control for three axes is provided by a single LSI device.

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.