The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Dec. 25, 1990
Filed:
Jan. 31, 1989
Applicant:
Inventors:
Kenneth E Daggett, Murrysville, PA (US);
Richard A Johnson, Murrysville Boro, PA (US);
Leonard C Vercellotti, Oakmont, PA (US);
Richard J Casler, Jr, Newtown, CT (US);
Eimei M Onaga, Pittsburgh, PA (US);
Lane L Woodland, Ross Township, PA (US);
Assignee:
Staubli International AG., , CH;
Attorney:
Primary Examiner:
Int. Cl.
CPC ...
G05B / ;
U.S. Cl.
CPC ...
31856816 ; 318599 ; 901 23 ;
Abstract
A pulse width modulation (PWM) control circuit provides for improved implementation of position, velocity and current feedback loops for digital servo control of a multi axis robot. The PWM circuit utilizes a single resistor for sensing joint motor drive current. Circuitry is also disclosed for reducing audible noise and motor heating in large servo motors used for joint arms operated at relatively low PWM frequencies by reducing the motor ripple current.