Development of a compact displacement accumulation actuator device for both large force and large displacement

The design, fabrication, and testing of a compact displacement accumulation device is presented in this paper, The piezoelectric device provides both large displacement (mm) and large force (100 N). The device is based on con ventional inchworm motor design that produces large displacement. The devic e integrates piezoelectric stacks for large force output and high-speed ope ration with MEMS ridges as a new clamping system. The device should be able to push and pull 450 N at 11 mm/s in a relatively compact size. FEM analys is is used for the design, EDM is used for the fabrication of a prototype, and conventional test techniques are used to evaluate performance. Stress a nd modal analysis are used to confirm that the device has an infinite fatig ue life and a first modal frequency at 1309 Hz. Experimental data for clamp ing strength of the ridges and blocking force of the device validate that t he device transfers the required load of 450 N. The device is successfully tested over a wide range of operating conditions at speeds up to 11 mm/s us ing open loop control. The stall load of the device is measured to be excee ding 2250 N. For the dynamic loading test, the device pushes test weights u p to 50 N with the open loop control approach. (C) 2001 Elsevier Science B. V. All rights reserved.