Papers by Keyword: Displacement Amplifier

Abstract: The bridge-type displacement amplifier is modeled by the analytical method and finite element method. The analytical relationship between the input displacement and output displacement is established. The analytical model is validated by finite element method. The geometric parameters influence of amplification ratio is studied. The comparison results show that the link length and the link angle influence the amplification ratio dramatically. A small link angle and a large link length is beneficial to the amplification ratio. The finite element method has a more precise simulation results than the analytical method under the circumstance of small link angle and short link length.

Abstract: The green fixture is the research focus, but the current research is centralized on the fixture driven by the air. It will lead to a noise polution and a small clamping force. Using the green electromagnetic conversion technology, a new clamping system to clamp the workpiece is provided, which is composed of the giant magnetostrictive material as working medium and the displacement amplifier with the area effect. This device can realize the flexible configuration of clamping at multi-place, for multi-workpiece and in multi-direction. Furthermore, this clamping system using the A/D converter and the sensor technology of pressure and displacement to collect the relative data, the collected data can to be putted in the computer and be processed，so it is easy to control the clamp force and clamping displacement intelligently.

Abstract: In this paper, a smart structure for the micro position control is proposed using the piezo stack actuator. The smart structure is comprised with PZT based stack actuator, mechanical displacement amplifier and positioning devices. Based on the bridge-type flexural hinge mechanism, a displacement amplifier is designed and integrated with a piezo stack actuator to produce a desirable positioning stroke of the device. In order to achieve the high precision control performance in a positioning device, a stick-slip phenomenon should be suppressed in contacting surfaces of the device, which is generally indispensable in the mechanically connected systems and particularly obvious for the micro-scale system. Therefore, the stick-slip model is enhanced by theoretically calculating the static friction based on the statistical rough surface contact model. Then, a PID feedback control algorithm with the developed stick-slip model is formulated for achieving accurate positioning of the device. Using the proposed smart structure, simulations of precise position control under the representative operating condition of positioning are conducted to demonstrate the stick-slip suppressing and micro positioning performance.

Abstract: In this paper, a stick-slip compensation for the micro-positioning is presented using the statistical rough surface contact model. As for the micro-positioning structure, PZT (lead(Pb) zirconia(Zr) Titanate(Ti)) actuator is used to drive the load for precise positioning with its high resolution incorporating with the PID (Proportional Integral Derivative) control algorithm. Since the stick-slip characteristics for the micro structures are highly nonlinear and complicated, it is necessary to incorporate more detailed stick-slip model for the applications involving the high precision motion control. Thus, the elastic-plastic static friction model is used for the stick-slip compensation considering the elastic-plastic asperity contact in the rough surfaces statistically. Mathematical model of the system for the positioning apparatus was derived from the dynamic behaviors of structural parts. Since the conventional piezoelectric actuator generates the short stroke, a bridge-type flexural hinge mechanism is introduced to amplify the linear motion range. Using the proposed smart structure, simulations under the representative positioning motion were conducted to demonstrate the micro-positioning under the stick-slip friction.

Abstract: The micromanipulator is basically required sufficient workspace and high natural frequency. However, previous designs are hard to satisfy the required workspace and natural frequency simultaneously. In this study, a previous design was analyzed from the viewpoint of the axiomatic design. Then, a new design parameter as displacement amplifier which transforms a coupled design into a decoupled design, was suggested. And a design procedure based on axiomatic design was developed. A spatial 3-DOF parallel-type micromanipulator was chosen as an exemplary device. According to the suggested design procedure, the micromanipulator having the required natural frequency was designed in the first step, and then the displacement amplifier satisfying the required work space was designed sequentially. To check the effectiveness of the manipulator and displacement amplifier, simulations and experiments were performed. Those are verified that the displacement amplifiers implemened work very well for satisfying the required task workspace.

Abstract: Sufficient workspace and high natural frequency of a micromanipulator are the fundamental requirements in its design. In this study, a previous design was analyzed from the viewpoint of the axiomatic design. Then, a new design parameter as displacement amplifier which transforms a coupled design into a decoupled design, was suggested. And a design procedure based on axiomatic design was developed. A planar 3-DOF parallel-type micromanipulator was chosen as an exemplary device. According to the suggested design procedure, the micromanipulator having the required natural frequency was designed in the first step, and then the displacement amplifier satisfying the required work space was designed sequentially. To check the effectiveness of the manipulator and displacement amplifier, simulations and experiments were performed. Those are verified that the displacement amplifiers implemened work very well for satisfying the required task workspace.