Design and fabrication of a hybrid actuator

• Published in: Smart materials and structures Vol. 14; no. 4; pp. 488 - 495
• Main Authors: Fu, Yao, Ghantasala, Muralidhar K, Harvey, Erol, Qin, Lijiang
• Format: Journal Article
• Language: English
• Published: Bristol IOP Publishing 01.08.2005; Institute of Physics
• Subjects: Exact sciences and technology; Fundamental areas of phenomenology (including applications); General equipment and techniques; Instruments, apparatus, components and techniques common to several branches of physics and astronomy; Measurement and testing methods; Physics; Servo and control equipment; robots; Solid mechanics; Structural and continuum mechanics; Electromagnetism; Microactuators; Test standard; Permanent magnets; Magnetic measurement; Finite element method; Permalloy; Composite materials; Standard test; Vinylidene fluoride polymer; Piezoelectric actuators; Electrodeposition; Modelling; Silicon; Laser beam machining; Copper; Electromagnetic testing; Polymers; Electromechanical properties
• ISSN: 0964-1726; 1361-665X
• DOI: 10.1088/0964-1726/14/4/005

The necessity to reduce the size of actuators and at the same time increase the force and the air gap has placed severe constraints on the suitability of current microactuator technology for various applications. This has led to the development of new actuator technologies based on novel materials or modifying existing systems. As an effort in this direction, we are reporting on the design and fabrication of a hybrid actuator employing a combination of electromagnetic and piezoelectric actuation methods for the first time. This actuator was designed and optimized by using the piezoelectric and electromagnetic solvers of commercially available FEM software packages (CoventorWare and ANSYS). The device consists of a shaped piezoelectric composite cantilever on the top and a copper coil wound around a permalloy core assembled on a silicon substrate with a permanent magnet at the bottom. The composite cantilever consists of polarized piezoelectric polymer polyvinylidene fluoride (PVDF) with an electroplated permalloy layer on one side. Microstructures in the required shape are introduced using novel methodologies including laser micromachining and microembossing. The hybrid actuator has been fabricated and tested using standard testing procedures. The experimental data are compared with the simulation results from both the finite element methods and the analytical model. There is excellent agreement between the results obtained in simulation and by experiment. A maximum total deflection of 400 mm with a typical contact force of 200 mN has been achieved.