Papers by Author: Cong Yu Xu

Abstract: Because of the large diameter’s big volume, heavy weight, high thermal capacity and bad measurement environment, the workpiece’s diameter can only be detected in the processing locale. Though the rolling-wheel method can realize the large diameter online measurement, it can not achieve the diameter high precision measurement influenced by rolling-wheel skidding, compression deformation and temperature distribution. Focusing on the above problem, a new multi function rolling-wheel large diameter measurement system is designed. The designed system mainly researches the main error resource’s distinguish and amendment methods, such as the round grating graduator error, rolling-wheel shape error, rolling-wheel compression deformation, skidding of rolling-wheel to measured axis workpiece and its non-uniform temperature etc. The system can obtain the measured axis’s diameter and roundness real time while getting the needed information of error amendment by integrating multi opto-electronic switch, round grating, reference grating, micro-displacement sensor, temperature sensor etc. The system can realize diameter measurement extended uncertainty 5Dμm(D:1m～10m) and roundness measurement extended uncertainty 1.5Dμm.

Abstract: A grating nanomeasurement device based on TMS320F28335 was presented, a novel subdivision algorithm for nanomeasurement was put forward and implemented in TMS320F28335. The analysis and test show that, through the pre-amplifying circuit well designed and through the data process algorithm optimized, the device applied with 20m pitch grating can realize 2nm resolution and greater than 200mm/s measurement speed. The experimental results of nanopositioning also demonstrate that the grating nanomeasurement device developed by the paper can be taken as nanomeasurement equipment used in nano-CMM and nanopositioning system.

Abstract: This paper has developed the bimodal USM a novel actuation pattern, which can actuate the bimodal USM in nanometer magnitude with single actuation pattern instead of combination control of AC actuation pattern, pulse actuation pattern and DC actuation pattern. The novel actuation pattern utilizes a single chip micro-computer to produce a kind of wavelet actuation unit which contains several sine voltage waves with different amplitudes, each wavelet actuation unit is exerted on bimodal USM according to the instruction, by which the step control is obtained. Across the two electrodes of bimodal USM, the differential wavelet actuation voltages are applied to reduce the moving distance of each actuation step, thus the nanometer magnitude actuation sensitivity is achieved. The grating is used as position sensor and the subdivision formulae of mutual compensation functions are adopted to promote the real-time response. The experiment indicated that, with the novel wavelet differential actuation pattern, the actuation characteristic of bimodal USM was improved, the micro-nanometer positioning control was easy to be implemented and the important positioning control parameters under every different actuation conditions could be obtained through the study in the process of actuation.