| 摘要 |
PURPOSE:To strengthen the rigidity of the whole servo system and to remove a wow and flutter by lowering the band of a low-pass filter, when the difference between estimated and actual positions is small, and by raising said band, when the difference is large. CONSTITUTION:When a difference obtained by subtracting the output pulse count Y of a low-pass filter from the output pulse count X from an encoder is integrated by an integrating term 1, the output E of the integrating term is the difference between the actual position of a servomotor and the position estimated by the low-pass filter. Therefore, when the output E of the integrating term 1 becomes smaller, the frequency band fn of the filter is lowered and when the output E is made larger, fn is raised so that a wow and flutter by quantization is eliminated. That is, when the output E of the integrating term is not more than 1 pulse, the band frequency fn is made low f1 and when the output E is not less than 2 pulses, fn is made higher f2. |
