本文提出一個增加數位控制平台穩定性與精度的方法，利用一組線圈與馬達定子的磁場作用產生非接觸力，使用的過程不會產生廢料，不會對環境造成污染，很適合用在低摩擦或無摩擦系統上。本文提出的方法成功克服數位控制到定位的目標區間後控制力為零，系統沒有任何力量抵抗環境或是其它干擾的問題。利用本文提出的方法，可在目標區間內產生一回復力，隨位置改變即時修正誤差，降低因擾動以及編碼器產生的誤差，讓馬達在定位區間內穩定擺動，達到零誤差的超精密定位。本文利用簡單的輔助機構，在不增加硬體成本的情況下，不用任何閉迴路控制，只需要在任何想要定位的位置上，給予輔助機構適當的電流，即可有效改善數位控制定位到硬體極限後，編碼器的量化誤差對定位精度產生的影響。除此之外，也可增加對外界干擾的扺抗能力，降低因外界干擾產生的誤差，有效提高定位精度。

In this paper, we proposed a method to generate the non-contact force by using the magnetic interaction between the coils and stators and it is suitable for the low friction or frictionless systems because of no waste materials generated during the process and there is no environmental pollution to be concerned. This way successfully overcame the problem about lacking of force to resist the disturbances between the aim zone by digital control. Applying the method we proposed, it can generate a restoring force in the aim zone and correct the error by its position changing in time and decrease the error caused by the disturbances and the encoder. Under the situation, the motor steady moved in the aim zone only and ultra precision position is reached. We used a simple accessory mechanism with adding proper currents on the position we set and we can sufficiently improve the effect about the encoder quantized error in positioning precision when the hardware limitation is reached with digital control for no closed-loop control applied and no extra hardware cost paid. Besides, we can enhance the ability to resist the disturbances and decrease the error caused by the disturbances and thus positioning precision is increased sufficiently.

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