Method and apparatus for measuring velocity and position in servo systems
US4639884A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Mar 5, 1984 |
| Grant date | Jan 27, 1987 |
| Priority date | — |
| Expiry date | Mar 5, 2004 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG05B2219/42212
- WIPO fieldControl
- WIPO sectorInstruments
Abstract
Method and apparatus for measuring the velocity, whether rotary or reciprocating, of a servo shaft driven by a motor, without employing a tachometer. From the movement of the shaft is produced a pair of signals in quadrature, with transitions expressible in Gray code for one cycle as 00, 01, 11, 10 and then back to 00. Meanwhile, a clock provides a large number of evenly spaced counts per selected quadrature transitions. The number of counts between two selected quadrature transitions is read and the total number of quadrature transitions between the selected transitions is divided by the total number of counts during the same time.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.