| 摘要 |
PROBLEM TO BE SOLVED: To make driving stable and to reduce a control deviation sufficiently by executing driving with successive reference to a reference table wherein information on a change in thrust at each point in a driving direction is held. SOLUTION: According to a target value generated by a target position generating means 5, a movable element of a multiphase linear motor is moved to a first position at a prescribed speed and then it is driven to a second position at a prescribed speed. On the occasion, a microprocessor 6 stores positions of the movable element and an output value to a D/A converter 7, i.e., a target current value, in a memory 3 successively at a prescribed period and executes filtering and a processing for normalization, so as to obtain a reference table. Based on positional information obtained from a position detector 10, a means 2 for referring to the table refers to the table in conformity with a rule and obtains the value of a thrust correction coefficient at the spot. The thrust correction coefficient thus obtained is used in a form wherein a value obtained as the result of execution of compensative computation of PID or the like by a controlling computation means 4 is multiplied thereby, and the result thus obtained is inputted to the D/A converter 7 so as to drive the multiphase linear motor. |
