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The piezoelectric actuator shows good control of micro linear displacement, but it cannot directly output the angular displacement. In this paper, an angular displacement piezoelectric actuator is proposed, which can amplify the displacement of the piezoelectric stack and realize angular displacement output just through one piezoelectric stack. Finite element modelling (FEM) simulations were used to analyse the angular displacement and the stress conditions. To verify the results of the FEM simulations, a prototype was manufactured and the experiments were performed. The maximum angle displacement was 0.85 ◦ when the driven voltage was 120 V.

In this paper, a system for supplying electric power and signal transmission wirelessly for the hydrostatic loading device is put forward. The electric power supplying and signal sending module of the system adopt contactless transmission method, which is commonly called CPT (contactless power transmission). Energy, with the form of a certain frequency of magnetic field, gets through the austenitic stainless steel. Being used as the chamber of the system, the austenitic stainless steel has the same relative magnetic permeability as the vacuum. After travelling through the chamber wall, energy is captured by the coil inside the chamber. Then it is converted into DC power and sent to the loads inside the chamber (1). Signal processing and sending module converts the analog signals into digital ones and restore them. Data consisting of signals is sent out from the chamber with the form of magnetic wave. Devices outside the chamber receive the data and recover it.

Tilt-positioning mechanisms are required in optical systems for diverse applications. Compared to electromagnetic tilt-positioning mechanisms, piezoelectric tilters are superior with regard to high positioning resolution, cost-effectiveness, and no electromagnetic interference issues. But their applications are limited by small motion ranges. To overcome this problem, a novel piezoelectric tilt-positioning mechanism is proposed and developed in this paper, aiming to achieve a large output range in compact size. Serving this purpose, flextensional piezoelectric actuators (FPAs) are employed in this mechanism and their optimal structure is pursued. The existing approach to model and analyze the structure of FPAs is not perfect, making it challenging to exactly characterize and optimize actuator performance for its applications. To address this problem, a hybrid-body model of the FPAs is developed and based on this model, a governing equation is established to exactly and comprehensively characterize their kinematic performance. This equation allows the application requirement to be readily related to the actuator design, enabling the optimization of tilter design and the actuators. Using the optimized parameters, an experimental prototype is fabricated. This specimen achieved more than 15 mrad of angular travel at a small size of 35 × 42 × 42 mm, and the error between the analytical model and the experiment was less than 5%. These results support the accuracy of the hybrid-body model and indicate that the proposed tilter is very promising for practical applications.

Mirror-scanning mechanisms are a key component in optical systems for diverse applications. However, the applications of existing piezoelectric scanners are limited due to their small angular travels. To overcome this problem, a novel two-axis mirror-scanning mechanism, which consists of a two-axis tip-tilt flexure mechanism and a set of piezoelectric actuators, is proposed in this paper. The focus of this research is on the design, theoretical modeling, and optimization of the piezoelectric-driven mechanism, with the goal of achieving large angular travels in a compact size. The design of the two-axis tip-tilt flexure mechanism is based on two nonuniform beams, which translate the limited linear output displacements of the piezoelectric actuators into large output angles. To exactly predict the angular travels, we built a voltage-angle model that characterizes the relationship between the input voltages to the piezoelectric actuators and the output angles of the piezoelectric-driven mechanism. Using this analytical model, the optimization is performed to improve the angular travels. A prototype of the mirror-scanning mechanism is fabricated based on the optimization results, and experiments are implemented to test the two-axis output angles. The experimental result shows that the angular travels of the scanner achieve more than 50 mrad, and the error between the analytical model and the experiment is about 11%. This error is much smaller than the error for the model built using the previous method because the influence of the stiffness of the mechanical structure on the deformation of the piezoelectric stack is considered in the voltage-angle model.