自德國政府率先提出「工業4.0計畫」(Industry 4.0)以來，便引發全球製造業進入智慧製造的時代，然而製造智慧化的基礎來自產線設備的各項感測元件、運動與控制、通訊，以及資訊整合與運算的能力。對於製造設備而言，超精密運動的定位技術決定著製造、組裝，甚至是量測的能力與層次，故本研究即以開發一超高解析度光學編碼器為目標，並透過對稱型壓電元件進行驅動，實現一高解析度光機電致動感測系統。
編碼器使用場域常伴隨油氣、灰塵等污染因素，造成編碼圖案遭覆蓋而導致誤判，本研究即針對此問題提出一基於質數編碼(Prime encoding)及曼徹斯特編碼(Manchester encoding)原則之編碼方式完成一具備10-bit/rev.解析能力且可容污之絕對式編碼；在均勻隨機分布的條件下，本研究所提之光學編碼可容許之髒污覆蓋面積可達11.25%，可適度的提升對於污染的容忍度；此外，本文也引入均勻設計實驗方法結合倒傳遞類神經網路(Back-propagation neural network, BPNN)進行細分割編碼之最佳尺寸設計，經實測，最佳之尺寸可得到動態範圍1.49V、半徑變異5.8%之之李沙育圖形(Lissajous plot)，提供編碼器14 bits之細分割的解析能力，結合上述之絕對式編碼可使綜效解析度達24-bit/rev。在驗證部分，本研究利用海德漢(Heidenhain) ROQ 437編碼器進行準確度(Accuracy)及精度(Precision)之測試，結果顯示本研究所開發之編碼器與ROQ 437之角度差異最大為0.0102°，精度則介於0.00028°至0.00079°，角度之有效位數達小數點後4位。在驅動部分則以一對稱型壓電元件(Symmetric Piezoelectric Element, SPE)與多連桿式預壓力機構(Multi-link Preload Mechanism)設計旋轉平台，完成壓電直驅旋轉平台之設計，最終將其與光學編碼器結合為高解析度光機電致動感測系統。
本研究透過創新的編碼原則以及系統化的最佳尺寸設計完成了一可容汙之絕對式碼盤，透過幾何光學設計、感測電路設計、壓電元件動態分析、驅動機構與電路設計等方法，最終實現了一綜效解析度達24-bit/rev.之絕對式光機電致動感測系統並驗證其可行性，未來可針對編碼器之光機進行進一步的精密組裝設計與細分割訊號補正，預期可改善角度訊號輸出之穩定性，進而提升角度感測的有效位數。

The introduction by the German government of “Industrie 4.0” (Industry 4.0) triggered the era of smart manufacturing in global manufacturing. However, the foundation of smart manufacturing lies in the various sensing components, motion and control, and communication of production line equipment, and its ability to integrate and compute information. For manufacturing equipment, the manufacture, assembly, and measuring ability and level are dependent on the ultra-precision motion positioning technology used. Therefore, this study aimed to develop an high-resolution optical encoder driven by symmetric piezoelectric elements (SPEs) to create a high-resolution opto-mechatronics actuation and sensing system.
The field of application of encoders is often influenced by pollution factors such as oil gas and dust, which leads to misreading because the encoding pattern is covered. This study proposed an encoding method that combines the prime encoding and Manchester encoding to achieve 10-bit/rev. absolute encoder with pollution tolerance. Under the condition of uniform random distribution, an optical encoder can tolerate 11.25% of the coverage area. Pollution tolerance can be appropriately enhanced according to the actual use environment. Additionally, this study introduced the method consists of uniform design and back-propagation neural network (BPNN) to find the optimal dimensions for transmission grating and incremental photodiodes (PDs). After actual testing, the optimal dimensions were obtained with a relating ADC value to the voltage of 1.49 V and Lissajous plot with 5.8% radial variation, providing the encoder with a 14 bits interpolation resolution capability, achieving the target of designing a 24-bit/rev. high-resolution absolute optical rotary encoder. The Heidenhain ROQ 437 encoder was used to verify the proposed design. The results revealed that the maximum angle difference between the encoder developed in this study and the ROQ 437 encoder was approximately 0.0102°. The precision ranged between 0.00028° and 0.00079°, and the significant digits of the angle were 4 digits after the decimal point. For the actuator, this study used an SPE and multi-link preload mechanism to design a rotary platform, completing the design of a piezoelectric direct drive rotary platform, which was then integrated with the absolute rotary optical encoder to form a high-resolution opto-mechatronics actuation and sensing system.
This study designed an absolute encoding disk with pollution tolerance through innovative encoding principles and a systematic optimal dimension design. Based on a geometric optics design, photodiode array (PDA) sensing circuit design, dynamic analysis of piezoelectric elements, and drive mechanism and circuit design, an absolute opto-mechatronics actuation and sensing system was achieved with a 24-bit/rev. synergy resolution and its feasibility was verified. Future studies could design a more advanced opto-mechanical precision assembly for the encoder and apply the signal error compensation method to improve the stability of angle signal output, thus enhancing the significant digits for angle sensing.

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