| 摘要 |
PROBLEM TO BE SOLVED: To improve position detection accuracy of a control target to allow accurate motor control.SOLUTION: A rotary shade 26 varies light distribution by a lighting fixture. A stepping motor 39 displaces the rotary shade 26. A motor control part 100 drives the stepping motor 39. A first position acquisition part 101 acquires a present angle position Pc of a drive shaft of the stepping motor 39. A second position acquisition part 102 acquires a target angle position Pt of the drive shaft from an integral control part 14. A difference acquisition part 103 periodically acquires a difference D between the present angle position Pc and the target angle position Pt. A speed calculation part 104 acquires a calculation value Va of a target rotational speed of the drive shaft on the basis of the difference D. An instruction acquisition part 105 acquires an instruction value Vb of the target rotational speed from the integral control part 14. A speed determination part 106 selects one of the calculation value Va and the instruction value Vb as a rotational speed V of the drive shaft. A signal output part 107 outputs a signal for rotating the drive shaft at the rotational speed V. |
