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In this paper, the mechanical gripper driven by pneumatic artificial muscle is taken as the research object, through theoretical analysis and experimental verification, the feasibility of force feedback control and incremental PID control applied to the mechanical gripper driven by pneumatic muscle is deeply studied, and the results of nondestructive and flexible grasping are obtained. The adaptive control process and deviation comparison link are designed to determine the expected output force of different items. Subsequently, the incremental PID control algorithm is used to eliminate the steady-state error, so as to achieve the self-adaptability of the control system to determine the expected force according to different items.

Mingzhou bridge in Ningbo is a half-through steel box arch bridge with 450m main-span. The bridge adopts welded steel structures except that abutments are made of steel composite structure. High requirements for the bridge construction technology are put forward because of the restrictions including poor geological conditions for bridge site, height limit for aircraft, narrow channel, frequent typhoon. The mid-span arch rib adopts cable hoisting and stayed buckle cable technology for the construction. This paper introduces the construction method during the assembled process of the mid-span arch rib. The numerical simulation analysis for the construction process is carried out. Stress and deformation of the main arch are in a reasonable range, which indicates completing the bridge construction control target successfully.

TA15 airplane wall panels are used widely in aircraft manufacture, which consist of some reinforced ribs and a motherboard. Therefore, welding sequences of different reinforced ribs directly determine distortion and residual stress distributions of welding wall panels, and then affect the structure service performance. Therefore, it is important to get the optimistic sequence during manufacture processing of welding wall panels. This paper analyses and predicts regularities of distributions of residual distortion and stress under four kinds of different welding sequence namely, order welding sequence, head-tail welding, head-tail symmetry welding and center symmetry welding. Compared the distortion and residual stress of four kinds of sequences, it is obvious that the welding distortion is smaller and welding quality is better under head-tail symmetry welding sequence, and the order welding sequence is the worst. The simulated distortions are in good agreement with the experiments. So this study puts forward the best welding sequence when welding airplane wall panels, which adapt to any amounts of reinforced ribs welded with the motherboard.

This paper conducted the outer constraint test of Coffin thermal fatigue and studied the deformation behaviors of microstructure for two kinds of welding deposited metals, they are 3Cr2W8 and HM3. The experimental results show that the thermal fatigue deformation belongs to multiple slip systems and the heterogeneous deformation mainly concentrates around the second phase particles. Moreover, it is found that the cracking initiation relates to the separation between the second phase particles and base body, void and micro-cracking formation.

In this research, we experimentally studied the spectral quality of the CUl324.7nm and Cul327.4nm lines of the copper alloy standard samples in argon atmosphere at reduced pressure by a laser microprobe emission spectral analysis (LMESA) system. Compared with the results obtained in air atmosphere with the pressure of 760Torr, the spectral quality of the lines obtained obvious improvement. As the distance between the two graphite electrodes is 4mm and the pressure is 250Torr, the intensity of the spectral lines is about 2-3 times of that in the air atmosphere and the Full-Width-at-Half-Maximum (FWHM) is nearly one third of that in the air atmosphere.