Using piezoelectric technology to improve servo gripper performance in mini‐ and microassembly

Abstract

Purpose -Aims to research the possibilities of using piezoelectric technology to improve accuracy and other characteristics of parallel servo grippers. Design/methodology/approach -The paper presents in detail two different kinds of developed two-fingered servo grippers based on piezoelectric technology with parallel moving mechanics. The first gripper is based on standing wave ultrasonic motors. The other gripper is a traditional gripper, the characteristics of which have been improved with integrated piezoelectric stack actuators. Both servo grippers have been tested and the test results and experiences are introduced in the paper. Findings -It is possible to improve the accuracy and characteristics of a parallel servo gripper with piezoelectric technology. Research limitations/implications -In the future it is necessary to concentrate on the mechanical design of gripper bodies and the fingers. Grasping force feedback signal should be even more linear and noiseless. Practical implications -Piezoelectric stack actuator's limited displacement is a problem in many practical applications when elastic or rough surface parts are handled. When integrated piezoelectric stacks are used with servo grippers, it is very important to focus on gripper's mechanical design and especially on the mechanical rigidity for getting the best possible results. Originality/value -Further developed versions of these servo grippers can be used in high accuracy industry applications instead of traditional servo gripper technologies.

Force-controlled automatic microassembly of tissue engineering scaffolds

“…According to their working principle, microgrippers can be divided into two major categories: active and passive microgrippers. Active microgrippers employ static electric [23], PZT [22], vacuum [24] or other kind of actuators to realize grasping and releasing action, while a passive gripper has no actuator, i.e. both grasping and releasing are realized by friction or specifically designed interfacing structures [25,26].…”

Single-Phase Drive Linear Ultrasonic Motor with Perpendicular Electrode Vibrator

“…Ultrasonic motors have many advantages, such as self-locking when unexcited, quick response, high power to weight ratio, quiet operation, high torque or thrust at low speed, and no electromagnetic interference. Consequently, ultrasonic motors are beginning to stand out against electromagnetic motors in some applications such as digital cameras, 1) cellular phone cameras, 2) mini-assembly systems, 3) and medical devices. 4) From a practical point of view, there has recently been a strong demand for ultrasonic motors owing to their affordability and compact size, especially in low-speed applications with high torque.…”