Papers by Author: Peng Jia

Abstract: In diamond cutting of optical glasses, the magnitude of critical depth of cut for brittle-ductile transition is an important factor affecting the machinability of the work material in terms of production rate and surface quality. In this work, scratching tests with increasing depths of cut were conducted on glass BK7 to evaluate the influence of the cutting fluid properties on the critical depth of cut. Boric acid solutions of different concentrations were selected as cutting fluids in the tests. The resulting scratches were examined utilizing a white light interferometer and the values of the critical depth of cut were determined based on the observations of the micro-morphology of the scratch surfaces produced. Experimental results indicated that compared with the process without cutting fluid action, the critical depth of cut in diamond cutting of glass BK7 can be increased by using boric acid solution as the cutting fluid.

Abstract: The fingertip force sensor is the key for the complex task of the dexterous underwater hand, in order to safely grasp an unknown object using the dexterous underwater hand and accurately perceive its position in the fingers, a sensor should be developed, which can detect the force and position simultaneously. Furthermore, this sensor should be used underwater. It is difficult to employ the accustomed calibration method for the characteristic of the fingertip force sensor, and the accustomed method is not able to assure the precision. A calibration method based on RBF (Radial-Basis Function) neural network is introduced. Furthermore, the calibration system and program are also designed. The calibration experiment of the sensor is carried out. The results show the nonlinear calibration method based on RBF neural network assure the precision of the sensor, which meets the demand of research on the underwater dexterous hand.