Finally, the voltage signal drops rapidly to zero from time t 1 to t 2. The movement of the cantilever beam of the monolithic elastomer drives the friction head to stick to the slider, and the slider then shifts forward by a step S F under the static frictional force. Then, from time t 0 to t 1, the piezo-stack is subject to power excitation from a slow-ramp voltage signal, which pushes the monolithic elastomer to move forward in the y direction, with the mounting part remaining completely fixed. First, the stage is at the original position without electrical input. The actuator operates in three steps over a full cycle, as shown in Fig. The respective material coefficients are listed in Table I.īased on the “stick–slip” driving principle, a sawtooth-wave signal with a fixed degree of symmetry is applied to drive the actuator. The friction head is made of a wear-resistant ZrO 2 ceramic. All parts except the piezo-stack and the friction head form a monolithic structure, which is made of AL7075 aluminum alloy. This design creates difference in structural stiffness between the two sides of the flexible hinged mechanism. The mounting part and the cantilever beam are separated by a slot.

In the other pair of elastic hinges, the two first ends are connected to the cantilever beam on the right side of supporting part B, and the two second ends are connected to supporting parts A and B, respectively. In the first pair of elastic hinges, the two first ends are connected to the mounting part on the left side of supporting part B, and the two second ends are connected to supporting parts A and B, respectively. A pair of parallel elastic hinges is mounted on each side of supporting part B. The friction head is glued to the top of the monolithic elastomer. The piezo-stack nests in the monolithic elastomer through mechanical capture. The monolithic elastomer is a so-called “flexure hinge mechanism,” consisting of five main parts: supporting part A, supporting part B, a mounting part, elastic hinges, and a cantilever beam. The actuator is composed of a piezo-stack, a friction head, and a monolithic elastomer. 10,11 Therefore, to overcome the existing shortcomings requires much work and further exploration.įigure 1 shows the detailed mechanical construction of the slim compact inertia actuator with dimensions of 32 × 14.5 × 3 mm 3. Piezo stick–slip actuators have the advantages of a simple structure, high resolution, and low power consumption, but problems such as low velocity and working noise remain. 7–9 However, these actuators require complex control methods and structures. 4–6 Walking piezo actuators operate at nonresonance frequencies and are characterized by excellent output mechanical characteristics and high resolution. 1–3 Travelling wave actuators have high output mechanical efficiency and rapid responses, but also suffer from problems such as heat loss and serious abrasion. Standing wave actuators have high output force, a compact structure, and high resolution, although their stroke is limited. These actuators can be divided into four common types: standing wave actuators, travelling wave actuators, walking piezo actuators, and stick–slip piezo actuators. The structures and working modes of piezo actuators vary depending on the working mechanism. With advantages such as simple construction, absence of electromagnetic interference, and rapid responses, piezo actuators have attracted much attention from researchers worldwide. It is shown that the inertia actuator based on a monolithic elastomer with a cantilever beam not only has a slim compact structure, but also exhibits good output characteristics. According to the results of these tests, the maximum velocity and maximum load force are about 24.03 mm/s and 1.96 N, respectively, and the minimum step size is about 0.47 μm. To study the actuator’s mechanical characteristics, a prototype is fabricated and a series of experimental tests are performed. Commercial finite element analysis software is employed to determine the appropriate geometry for the monolithic elastomer. The construction and basic operating principle of the actuator are discussed in detail. Actuated by the transverse motion of a cantilever beam forming part of a monolithic elastomer, this actuator achieves a high velocity. To overcome these shortcomings, this study proposes a slim compact piezo inertia actuator based on the principle of stick–slip drive. Most previously reported inertia actuators suffer from the problems of low speed and large size.

Piezo actuator amplitude