壓電式力量感測之低頻補償改善研究

Compared with other kinds of force sensors, the piezoelectric force sensor features high stiffness comparable to steel, extreme compactness, a large dynamic range, and a wide linear measurement range. However, the piezoelectric force sensor is unable to sense static and quasi-static forces. The proposed scheme uses a rigid-body model and also an adaptive algorithm to compensate for low-frequency parts of a piezoelectric force sensor's output. This project is an extension of the earlier project with a grant number, MOST 107-2221-E-003-021. In the previous project, accelerometers are required for force estimation, which increases system costs, complicates system structures and also reduces reliability of a system. The proposed project presents an improved design that does not require acceleration information for force estimation, reducing system costs and complexities and also increasing system reliability. Compared with existing force estimation algorithms, the proposed scheme does not require prior knowledge of system perturbation. The proposed scheme can produce an estimate of system perturbation as a byproduct and does not require implementation of an additional disturbance observer for perturbation compensation. Compared with previous piezoelectric static force sensors, the proposed scheme does not require to redesign a sensor structure or an electronic system and is able to simultaneously sense static and dynamic forces. Compared with a conventional strain gauge-based load cell, the proposed system features high stiffness and extreme compactness and almost preserves the stiffness of a system's mechanical structure. In this project, the proposed scheme was experimentally applied to a linear motor-based motion stage, demonstrating its applicability and feasibility. Since the proposed scheme has been practically applied to a physical mechatronic system, the graduate students involved in this project have received advanced training in Mechatronics and System Integration.