Precision positioning systems with large working stroke (millimeter or more) and micro/nano-scale positioning resolution are widely required in both scientific research and industries. For this kind of applications, piezoelectric materials based actuators show unique advantages and have been widely employed. To overcome the demerit of the limited working stroke for single piezoelectric element, various stepping motion principles have been proposed in the past years, and accordingly, stepping piezoelectric actuators with various structures have been designed and evaluated. This review is aimed to summarize the recent developments and achievements in stepping piezoelectric actuators with large working stroke. Especially, the emphasis is on three main types of stepping piezoelectric actuators, i.e., inchworm type, friction-inertia type, and parasitic type. The motion principles of these three types of piezoelectric actuators and the corresponding developments of various actuators are discussed respectively, followed by pointing out the existing problems in these three types of piezoelectric actuators and proposing some potential research directions in this topic. It is expected that this review is helpful for relevant researchers to understand stepping motion principles as well as piezoelectric actuators, and to successfully select and design stepping piezoelectric actuators for specific applications.

Stepping piezoelectric actuators with large working stroke for nano-positioning systems: A review

A trapezoid-type stick–slip piezoelectric linear actuator using a right circular flexure hinge mechanism was proposed, designed, fabricated, and tested with the aim of accomplishing linear driving based on stick–slip motion. The angle adjustment of the trapezoid beam was used for generating lateral motion on the driving foot of the flexure hinge mechanism. A method of tuning the lateral motion of the flexure hinge mechanism was discussed. Based on the finite-element method, a proper angle of the trapezoid beam was obtained. The analysis results proved that asymmetrical flexure hinge mechanism can increase static friction force in slow extension stage and decrease kinetic friction force in quick contraction stage by lateral motion of the driving foot. A prototype was fabricated and its experimental system was established. The mechanical output experiments showed that the prototype achieved maximum output velocity and load of 5.96 mm/s and 3 N at a voltage of 100 V $p-p$ and a frequency of 500 Hz, respectively.

A Novel Trapezoid-Type Stick–Slip Piezoelectric Linear Actuator Using Right Circular Flexure Hinge Mechanism

A piezoelectric actuator based on parasitic motion principle is proposed and tested. The piezoelectric actuator is explored to simultaneously realize coarse (long stroke) and fine (high accuracy) motions using dual-servo control method. The working principle of the proposed piezoelectric actuator is discussed, and finite-element method is adopted. A dynamic model of parasitic motion based on the LuGre friction model is simulated using matlab /Simulink. A prototype is manufactured to investigate working performance. Experimental results indicate that the maximum speed of the presented parasitic-type piezoelectric actuator is 7.95 mm/s and the resolution is 10 nm. These findings confirm the feasibility of the dual-servo nanopositioning system using piezoelectric stacks and flexure hinges.

Development of a Novel Parasitic-Type Piezoelectric Actuator

This paper provides a comprehensive review of the literature regarding precision piezoelectric motors over long ranges based on the principle of repeating a series of small periodic step motions, named “frequency leveraged motors” in this paper. A summary of recent research into frequency leveraged motors is presented. Work is classified into three categories by different frequency driving methods, including ultrasonic motors, quasi-static motors (non-resonant motors), and motors combined resonant and quasi-static operations. Pros and cons of each motor type are discussed in term of their principle, structure, and performance. In addition, future perspectives and improvements of the frequency leveraged motor are also provided. It is summarized in such a way can provide a better understanding of the core characteristics of each type of long range piezoelectric motor. Moreover, it also aids in determining successful designs, suitability for applications and further research areas.

A review of long range piezoelectric motors using frequency leveraged method

A piezoelectric-driven actuator based on coupling motion has been proposed and tested to achieve a large linear working stroke with high resolution. “Z-shaped” flexure hinges are exploited for the symmetric flexure hinge mechanism to reduce the structural stress. Coupling motion is obtained by placing this symmetric flexure hinge mechanism with an angle of $\theta =20^\circ $ to the slider. Experimental results indicate that linear motion with a large working stroke is effectively obtained by this coupling motion; the maximum motion speed is $V_{s}=$ 6057 μm/s and the maximum output force is $F_{g}=$ 350 g. Additionally, the influences of input frequency $f$ and input voltage $U_{e}$ are investigated, and the system kinetic model is established to better analyze the performance of this designed piezoelectric-driven linear actuator.

A Piezoelectric-Driven Linear Actuator by Means of Coupling Motion

This paper presents a piezoelectric-driven stepping rotary actuator based on the inchworm motion. With the help of nine piezoelectric stacks and the flexure hinges, the designed actuator can realize large rotary ranges and high rotary speed with high accuracy. Three kinds of working units that compose the actuator are described and calculated: the clamping unit to hold the rotor, the adjusting unit to preload the piezoelectric stacks and the driving unit to produce the driving torque. To test the working performance, a prototype actuator was fabricated, and the experimental results indicate that the minimum stepping angle is 4.95 μrad when the driving voltage is 20 V and the frequency is 1 Hz, the maximum output torque is 93.1 N mm under the driving voltage of 100 V and the maximum velocity can be 6508.5 μrad/s when the frequency reaches 30 Hz. The experimental results verify that the proposed actuator can realize different stepping angles and rotation speeds with high accuracy under different driving voltages and frequencies.

A piezoelectric-driven rotary actuator by means of inchworm motion

A piezoelectric positioning platform by means of inchworm motion principle is developed, and it can achieve both linear and rotary motions. The designed positioning platform can provide large range motion with high resolution in a compact size. Eight piezoelectric stacks and several flexible hinges are used in the stator and the slider. The working principle of the proposed positioning platform is analyzed. Experiments of the prototype are carried out and the results show that the developed positioning platform has stable working characteristics under the certain working conditions. For the rotary motion of the positioning platform, the minimum stepping angle is 0.23 μrad, the maximum rotary velocity is 3521.70 μrad/s and the output torque is 0.294 N m. When the platform works in the linear model, the minimum stepping displacement is 0.15 μm, the maximum velocity is 105.31 μm/s and the largest output load is 4.9 N. The designed positioning platform can be used in the fields of nanotechnology, precision machining, MEMS, bioscience and so on.

Development of a compact 2-DOF precision piezoelectric positioning platform based on inchworm principle

In this paper, a novel piezo-driven rotary actuator with the changeable clamping radius is developed based on the inchworm principle. This actuator mainly utilizes three piezoelectric actuators, a flexible gripper, a clamping block, and a rotor to achieve large stroke rotation with high resolution. The design process of the flexible gripper consisting of the driving unit and the clamping unit is described. Lever-type mechanisms were used to amplify the micro clamping displacements. The amplifying factor and parasitic displacement of the lever-type mechanism in the clamping unit was analyzed theoretically and experimentally. In order to investigate the rotation characteristics of the actuator, a series of experiments was carried out. Experimental results indicate that the actuator can rotate at a speed of 77 488 μrad/s with a driving frequency of 167 Hz. The rotation resolution and maximum load torque of the actuator are 0.25 μrad and 37 N mm, respectively. The gripper is movable along the z direction base...

Design and experimental research of a novel inchworm type piezo-driven rotary actuator with the changeable clamping radius

The utility model relates to a positive pressure adjustable micro nano stick slip inertia drive platform, and relates to precision and ultra precision machining, micro nano operation robots, micro electro mechanical systems, large-scale integrated circuit manufacturing, biotechnology and other important fields of science and engineering. The device is mainly composed of a positive pressure adjustable precision drive unit and a linear motion unit. The precision drive unit is composed of a manual precision translation stage and a piezoelectric driver. The manual precision translation stage can adjust the positive pressure between the piezoelectric driver and a workbench. Piezoelectric stack is packaged in the piezoelectric driver. The linear stepping feeding of the workbench is realized based on a stick slip principle. The linear motion unit is composed of a precision rolling guide and a workbench, and the linear motion of the worktable is ensured. The positive pressure adjustable micro nano stick slip inertia drive platform provided by the utility model can be used for the fields of high precision drive and machining, large-scale integrated circuits and micro operation robots, and has the advantages of simple structure, stable work, high efficiency, less investment, high benefit and the like.

Positive pressure adjustable micro nano stick slip inertia drive platform

This paper presents a novel piezo-driven rotary actuator based on the parasitic motion principle. Output performances of the rotary actuator were tested and discussed. Experiment results indicate that using only one piezoelectric actuator and simple sawtooth wave control, the rotary actuator reaches the rotation velocity of about 20,097 μrad/s when the driving voltage is 100 V and the driving frequency is 90 Hz. The actuator can rotate stably with the minimum resolution of 0.7 μrad. This paper verifies feasibility of the parasitic motion principle for applications of rotary actuators, providing new design ideas for precision piezoelectric rotary actuators.

Han Qu

Papers

A piezoelectric-driven rotary actuator by means of inchworm motion

Development of a compact 2-DOF precision piezoelectric positioning platform based on inchworm principle

Design and experimental research of a novel inchworm type piezo-driven rotary actuator with the changeable clamping radius

Positive pressure adjustable micro nano stick slip inertia drive platform

Note: A novel rotary actuator driven by only one piezoelectric actuator