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Wei Zhouhong
Input/Output Company,
12300 Parc Crest Drive,
Stafford, Texas 77477, USA
Schinstock Dale E
Mechanical & Nuclear Engineering,
Kansas State University,
Manhattan, Kansas 66506, USA |
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FEEDFORWARD
CONTROL
STRATEGIES FOR TRACKING
PERFORMANCE IN MACHINE AXES*
Abstract: Three feedforward (FFD) control techniques for position-servo machine axes are compared. All three FFD controllers are used with two different PID feedback (FBK) controllers. The two different FBK controllers have two different closed-loop bandwidths. They are demonstrated using experimental data from a linear motor test system and from simulations. Laboratory results using the linear motor hardware demonstrate that the velocity & acceleration (V&A) FFD controller improves tracking in all case considered, while the other two FFD controllers actually degrade performance in many cases. Through simulation this degradation is attributed to extreme sensitivity to round off errors. This sensitivity is the result of a complex controller that is implemented outside of the feedback loop.
Key words:
Three feedforward (FFD) control Linear motor system Tracking |