Papers by Author: Xiu Long Chen

Abstract: In order to improve kinematics performance of high-speed spatial PCMM(parallel coordinate measuring machine), the comprehensive dexterity coefficient, which are defined to evaluate the whole dexterity of various configurations, was applied to the kinematics performance optimization of PCMM. By analyzing three dexterity measures, including conditional number, the smallest singular value and operation of PCMM, the comprehensive dexterity coefficient was proposed. The influence law of the distribution position angle of the joints on the stationary platform and moving platform, the distribution position radius of the joints on the stationary platform and moving platform on the comprehensive dexterity coefficient were discussed. On these grounds, the distribution position angle of the joints on the stationary platform and moving platform, the distribution position radius of the joints on the stationary platform and moving platform were optimized. The simulation results show obvious improvement of the kinematics performance for PCMM, so that the powerful theoretical basis and method of optimization design for the PCMM are provided.

Abstract: In order to improve performance of 4-UPS-RPS high-speed spatial parallel robot, the elastic dynamics optimization design was executed. The influence law of the mass of moving platform and the diameter of driving limbs on the dynamic performance, which includes kinematics output response and maximum dynamic stress of driving limbs, were discussed. On these grounds, the mass of moving platform and the diameter of driving limbs were optimized. The simulation results show obvious improvement of the dynamics performance for 4-UPS-RPS parallel robot, therefore the theoretical basis are provided.

Abstract: In order to solve spring-back problem of the stamping forming process, A method for stamping forming and spring-back process simulation of automotive panel by finite element technologies was proposed. The solid model of automobile right side strengthening panel was created in UG software and transmitted to Dynaform. The stamping forming and spring-back process simulation were realized by using Dynaform. The distribution of strain, the variety of the sheet thickness and the spring-back were analyzed. The maximum stress or strain, the minimum thickness and the maximum spring-back were obtained. The simulation results can reflect the real stamping forming of the strengthening panel, and forecast the possibly spring-back value in stamping process. This research can optimize the stamping process and provide strong references for the design of the automotive panel die.

Abstract: A novel 5-Degree of Freedom PCMM (parallel coordinate measuring machine) was proposed, and its motion control system was designed. Compared with the other structural PCMMs, the structure feature of proposed PCMM was described. Then its motion control system was designed with the modularized and open architecture. The controlled scheme of hardware, which based on PC, PMAC motion control card and the precision measuring probe, was developed. The software of the motion control system was written by Visual Basic6.0 language. Finally, the process of motion control for 4-UPS-UPU PCMM was proposed. The new method above for design of motion control system is simple and effective, and may be applied to other parallel machine.

Abstract: In order to grasp the vibration characteristics of a novel High-Speed 4-HPS-HPH PMT(parallel machine tool), A vibration behaviors analysis method using virtual prototype simulation was put forward. By the united application of CAD, CAE and visual technologies, the rigid-flexible vibration model of 4-HPS-HPH PMT was constructed. Then the dynamic response of the tool tip, including vibration displacement, vibration velocity, vibration acceleration, and maximum dynamic stresses of driving limbs were realized. The simulation results show that the rigid-flexible vibration model proposed can indicate the vibration behaviors of parallel machine tool. This research provides necessary guidance for dynamic performance analysis, optimization design and control of this 4-HPS-HPH PMT.

Abstract: In order to obtain dynamic behaviors of a spatial rigid-flexible coupling system of PMT(parallel machine tool) without the construction of mathematical model, a new method for dynamic behaviors simulation, which integrates CAD, CAE and visual technologies, was presented. The solid model of PMT was built in SolidWorks and transmitted to ADAMS, the modal neutral file of flexible body including driving limbs and spherical joints were generated in ANSYS, and introduced into ADAMS, then the rigid-flexible coupling model of PMT was build. Based on the rigid-flexible coupling model, the dynamic behaviors, which includes displacements error output response, dynamic stress of driving limbs and natural frequency, were realized. The simulation results show that the rigid-flexible coupling model established can indicate the dynamic behaviors of PMT. The flexibility of driving limbs and spherical joints are demonstrated to have significant impact on dynamics characteristics of PMT. This research can provide the important theoretical base of the optimization design of dynamic parameters for PMT.

Abstract: The gear plunge shaving process is a widely used process for soft finishing of gears in the gear manufacturing industry. But it is difficult and expensive to profile plunge shaving cutter, because the cutter must be ground by a cone grinding wheel on a special grinder. A new method, profiling gear shaving cutter on the shaving machine, i.e. a CBN dressing gear which has the same parameters with the machined gear is clamped in place of the workpiece on the shaving machine and profiling the cutter in shaving process, is put forward. Meshing and Tooth contact analysis of shaving cutter profiling has been considered. Meshing equation of profiling process and equation of shaving cutter gear blank after profiling are obtained. Experiment testified that it is an applied method and has many advantages.