目前電動代步車調速用的電位計大都採用高品質的接觸式可變電阻，因產品要求可靠性與耐久性，故其價格高昂，另外還有接觸式膜片因長期使用而磨耗的問題。為解決這些問題，本研究採用磁性感測元件開發非接觸式電位計。因為本裝置沒有接觸的動件，磨耗的問題可被解決，而且以現存接觸式電位計相容的機構和電氣規格為原則，設計本裝置，因此降低成本。此外彈簧斷裂所導致的危害已在電路處理中給以隔離。本裝置的雛型已完成並經測試，測試的結果顯示可取代接觸式電位計。

At present, potentiometers employed for scooter speed regulation are high-quality contact-type variable resistors. They are expensive because of the requirements on reliability and durability and will inevitably incur problems of wearing after a long time in use. To obviate the above mentioned drawbacks, a non-contact potentiometer based on a well-established magnetism detector is developed in this paper. Since there is no contact, nor moving parts in the device, the problem of wearing is solved. Also, the potentiometer is designed to be completely compatible with existing contact potentiometers in terms of electrical and mechanical specifications. Hence, the cost for the device is cut down. Moreover, A broken spring that normally causes a hazard is isolated by the processing circuit by stopping the scooter. A prototype of the device has been built and tested. Results show that the device can be used as a replacement for traditional contact potentiometers.