Piezoelectric film-actuated motion platform with high resolution

Abstract

A piezoelectric film-actuated motion platform with high resolution, which can run in two directions within a horizontal plane, is presented. On the basis of the analysis of the working principle of a stick-slip mechanism, a mathematical model describing its dynamic behavior is set up and simulated. Experiments of the motion performance and carrying ability on the prototype are conducted. Results show that this type of platform has advantages including a simple structure, small volume, light weight, stable step length, and large traveling range. When the driving voltage is less than 30 V, step error is less than 0.5 mm. The carrying ability of the platform is terrific and about 7-8 times its weight.

Effect of Pulling Velocity on the Unidirectional Solidification Phenomenon of DZ417G Superalloy

“…In the present work, a macro-scale CALCOSOFT model and a meso-scale Cellular Automaton Finite Element (CAFE) model was used to simulate the temperature field, fluid field and structure evolution during directional solidification of DZ417G superalloy. As described in the literature [7], the macro-model CALCOSOFT was to simulate the macroscopic heat transfer and fluid flow by using a finite element solution of energy, momentum equations to determine the heat and momentum flow. Calculated thermal profiles were then coupled to the meso-model CAFE as input to predict grain structures and grain orientations of the castings.…”