Electrostatic Controlled Linear Inchworm Actuator

Nishio

Doki

et al. 2016

SUMMARY We propose a 3‐DOF inchworm‐type microactuator that uses levitation generated by vertical vibration. The vertical vibration is created by a piezoelectric actuator. The inchworm typically consists of thrust elements and clamp elements. The proposed inchworm, however, does not use any clamp elements. Four levitation elements are connected with four thrust elements, which are stacked‐type piezoelectric actuators. The levitation element consists of a mass, a piezoelectric actuator, and a plate. The vertical vibration of the piezoelectric actuator lifts the levitation elements, which eliminates any friction. By controlling the order of the deformation of the horizontal piezoelectric actuators and the vibration of the vertical piezoelectric actuators, the inchworm engages in linear and rotational motion. The levitation height and the linear and rotational displacement of the inchworm were measured. Experimental results demonstrated the feasibility of the proposed 3‐DOF inchworm. The mechanism described in this paper is effective for a precision positioning system in a clean room.

Section: Introductionmentioning

confidence: 99%

A 3‐DOF Inchworm Using Levitation Caused by Vertical Vibration

Nishio

Doki

et al. 2016

“…In addition there have been reports of mechanisms that can be driven on inclined planes, and of designs using closed magnetic circuits of electromagnets for position keeping . There are also inchworms using an electrostatic attractive force for position keeping , and high‐speed locomotion mechanisms using piezoelectric actuators for position keeping . There have been attempts to increase the travel speed of inchworms by using piezoelectric actuators that extend and contract in the vertical direction.…”

Section: Introductionmentioning

confidence: 99%

An Inchworm Using Levitation Caused by Vertical Vibration

Itatsu

Nishio

et al. 2014

SUMMARYWe propose an inchworm-type microactuator which uses levitation caused by vertical vibration. The vertical vibration is generated by a piezoelectric actuator. The inchworm usually consists of thrust elements and clamp elements. The proposed inchworm-type microactuator however does not use any clamp elements. Three levitation elements are connected with two thrust elements which are stacked piezoelectric actuators. The levitation element consists of a mass, a piezoelectric actuator, and a plate. The vertical vibration of the piezoelectric actuator lifts the levitation elements and eliminates the friction. By controlling the phase of the horizontal and vertical piezoelectric actuators, the inchworm moves in a linear direction. The levitation height and the position of the inchworm are measured, and experimental results show the feasibility of the proposed inchworm. The mechanism described in this paper is effective in a precise positioning system in a clean room. C⃝ 2014 Wiley Periodicals, Inc. Electr Eng Jpn, 190(4): 19-25, 2015; Published online in Wiley Online Library (wileyonlinelibrary.com).

“…By combining elements that maintain position by using electrostatic attraction and electromagnetic forces, piezoelectric elements, and other elements that create displacement, and synchronizing the movement of these elements, an infinite range of movement can be obtained [3,4]. By combining elements that maintain position by using electrostatic attraction and electromagnetic forces, piezoelectric elements, and other elements that create displacement, and synchronizing the movement of these elements, an infinite range of movement can be obtained [3,4].…”

Section: Introductionmentioning

confidence: 99%

“…However, there is also the inchworm mechanism, a mobile mechanism that is infinitely movable with no limits to its range of motion. By combining elements that maintain position by using electrostatic attraction and electromagnetic forces, piezoelectric elements, and other elements that create displacement, and synchronizing the movement of these elements, an infinite range of movement can be obtained [3,4]. We have performed research on various types of small mobile mechanisms using piezoelectric elements as structural units.…”

Section: Introductionmentioning

confidence: 99%

A small‐size self‐propelled Stewart platform

Banno

Ueda

et al. 2012

This paper describes a self-propelled Stewart platform. The Stewart platform usually consists of a base platform, a moving platform, and linear actuators connecting the platforms. We use six stacked-type piezoelectric actuators as linear actuators. Mechanical joints connected the linear actuators and both of the platforms. We inserted electromagnets between the linear actuators and the base platform instead of the mechanical joints. This structure enables the Stewart platform to move on a surface by using the principle of inchworm motion. While the electromagnets fix the linear actuators on the base platform, the proposed Stewart platform realizes a precise 6-DOF motion. Control signals are designed for small displacement based on inverse kinematics, and for a wide working area based on the principle of inchworm motion. The position and orientation of the moving platform are measured, and experimental results indicate the feasibility of the proposed mechanism. The mechanism is effective for a precise position system which has unlimited working space. © 2012 Wiley Periodicals, Inc. Electr Eng Jpn, 181(2): 37-46, 2012; Published online in Wiley Online Library (wileyonlinelibrary.com).