Method for positioning a tool of a multi-joint robot
US4894788A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Apr 21, 1988 |
| Grant date | Jan 16, 1990 |
| Priority date | — |
| Expiry date | Apr 21, 2008 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG05B19/414
- WIPO fieldControl
- WIPO sectorInstruments
Abstract
A method for positioning a tool of a multi-joint robot is disclosed in which an incorrect positioning of the tool resulting from nonideal geometrical relationships is compensated by the following steps: determining a preliminary desired angular position for each of the joints for a desired position in space of the tool based upon the reference distances and joint axis directions required to position the tool in the desired position; determining the positioning error of the tool due to the differences between the reference distances and the desired directions and the actual spacings and actual directions of the joints; transforming the determined positioning error into corresponding angular correction values for the preliminary desired angular positions of the joints by means of an inverse Jacobi matrix coordinate-transformation equation system; calculating the error-corrected angular position for each of the joints by addition of the angular correction values to the preliminary desired angular positions; and moving the tool to the desired position by rotating the joints in accordance with the error-corrected angular position calculated.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.