Abstract
This paper discusses the three-dimensional dynamic contouring errors attributed to a multi-axis robot system and introduces a new way of interpreting this contouring error based on a relaxed performance measure. With this concept, multi-axis contour errors can be reduced by matching delay times over a bounded frequency bandwidth rather than increased loop gains in the servo drives - an important 'scare source' for stability maintenance of the servo design. A generic contouring error model and simplified error-prediction model are derived, and estimated contouring errors are verified by experimental tests under matched and mismatched axis dynamic conditions. A procedure using relaxed performance measure for the axis controller design with unity gain, linear phase, and appropriate gain and phase robustness is then proposed. Finally, the compensator is implemented in a six-degress-of-freedom Cartesian-type gantry robot performing contouring operations. Axis test data validates the performance and robustness of the designed controller.
Original language | English |
---|---|
Pages (from-to) | var paging MS89-314 |
Journal | Technical Paper - Society of Manufacturing Engineers. MS |
State | Published - 1989 |
Externally published | Yes |