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Researches on forging manipulator have enormous influence on the development of the forging industry and national economy. Clamp device and lifting mechanism are the core parts of forging manipulator, and have been studied for longer time. However, the optimization and mechanical accuracy reliability of them are less analyzed. Based on General Function(G F) set and parallel mechanism theory, proper configuration of 10t forging manipulator is selected firstly. A new type of forging manipulator driven by cylinders is proposed. After solved mechanical analysis of manipulator’s core mechanisms, expressions of force of cylinders are carried out. In order to achieve smaller force afforded by cylinders and better mechanical characteristics, some particular sizes of core mechanisms are optimized intuitively through the combined use of the genetic algorithms(GA) and GUI interface in MATLAB. Comparing with the original mechanisms, optimized clamp saves at least 8 percent efforts and optimized lifting mechanism 20 percent under maximum working condition. Finally, considering the existed manufacture error of components, mechanical accuracy reliability of optimized clamp, lifting mechanism and whole manipulator are demonstrated respectively based on fuzzy reliability theory. Obtained results show that the accuracy reliability of optimized clamp is bigger than 0.991 and that of optimized lifting mechanism is 0.995. To the whole manipulator under maximum working condition, that value exceeds 0.986 4, which means that optimized manipulator has high motion accuracy and is reliable. A new intuitive method is created to optimize forging manipulator sizes efficiently and more practical theory is utilized to analyze mechanical accuracy reliability of forging manipulator precisely.

A novel type of mechanical presses design driven by three servo motors in parallel is proposed to develop high stamping capacity based on the theory of generalized function sets, and then is improved to enhance its practicability in engineering practice. The inverse and forward kinematics analyses are conducted later. Based on the fuzzy probability theory, the computing method of fuzzy reliability of kinematic accuracy of slider is then obtained. Finally, with a set of optimized length parameters of the presses given, the fuzzy reliability is calculated, on the basis of which a typical deep-drawing process is simulated.

The influence of the ultrasonic vibrated diamond tool on the transition of ductile cutting to brittle cutting of the glasses is investigated by facing turning. It is understood that the critical depth of cut for the ductile cutting of the brittle materials is increased obviously by the ultrasonic vibrated diamond tool. The optical quality surface of the glasses is obtained, the surface roughness of which is less than0.03m. Finally, the relation between the roughness of machined surface and the cutting distance is studied experimentally.

The experimental results for silicon carbide (SiC) wheel with fine grit size grinding of silicon carbide (Si3N4) revealed that the grinding parameters affect not only the ground silicon nitride surface roughness, but also the degree of surface damage. There exists complex non-linear relationship between the grinding parameters and surface quality. Better surface roughness doesn’t surely mean less surface damage. A method of prediction of grinding quality based on support vector regression is then presented according to the condition of small samples. The result shows the prediction accuracy based on this method is obviously higher than neural network, which provides an effective way for optimizing the grinding parameters to ensure the grinding quality as well as grinding efficiency while grinding of silicon carbide using conventional abrasive.

In this paper, an online measurement and error compensation system for curve grinding based on pattern recognition was presented and verified by experiments. The measurement system organization and its principle of operation were introduced in detail. The work piece and grinding wheel image were sampled at certain positions to avoid spark influence. In order to increase system resolution, images were sampled only at local areas of the work piece and grinding wheel. A discrimination technology based on a circular tolerance zone was proposed which can solve the problem of local image edge comparison. For image de-noising, a local threshold algorithm was applied to determine new wavelet coefficients. Furthermore, a two-step edge detection method was used to realize sub-pixel precision. Finally, a series of experiments were carried out to examine the detection precision of the image measurement system and its influencing factors. From experiments, it can be said that the proposed method in this paper is effective, and its detection precision is much better than traditional methods.

The fuzzy allowable intervals of the deflection, the vibration frequency and the fatigue strength of the shaft fixing grinding wheel are proposed in present paper based fuzzy set theory. According to fuzzy probability theory, the fuzzy reliability model of the rigidity, the fuzzy reliability model of the vibration and the fuzzy reliability model of the fatigue for the shaft fixing grinding wheel in internal grinding are given. The method is put into real example.

Chatter marks that limit ground surface finish have been observed in accurate grinding by using optical curve grinder. To reveal the mechanism of chatter marks, the relationships between grinding parameters and chatter marks are experimentally studied. The profile of the ground surface is analyzed through microscope as well as FFT method. It is found the dynamic characteristics of grinder and the vibration test are efficient tools for this study. Modeling of grinding chatter marks is proved effective for the result of simulation showing consistent with that of experiments. The results of study point out the way to eliminate chatter marks and establish the basis for detection and prediction of the marks.

The drilling assisted by ultrasonic elliptical vibration (UEV) is proposed in present paper. The drilling system assisted by UEV was developed. The characteristics of the drilling process assisted by UEV are analyzed. The effect of ultrasonic elliptical vibration on the axial drilling force, the radial drilling force and the chip thickness are investigated experimentally. The experimental results show that the axial drilling force, the variation of the radial drilling force and the chip thickness of drilling assisted by UEV can be reduced.

In the present paper, the thrust cutting force model in ultrasonic elliptical vibration cutting is proposed based on the principle of ultrasonic elliptical vibration cutting, and the reason of the thrust cutting force reduced by applying ultrasonic elliptical vibration is clarified theoretically. The effect of ultrasonic elliptical vibration on the thrust cutting force is verified experimentally.

The cutting speeds of the tool, the rake angle and clearance angle through the cycles of elliptical vibration cutting for separating type ultrasonic elliptical vibration cutting are defined initially in the present paper. Subsequently, a theoretical model of the thrust cutting force in ultrasonic elliptical vibration cutting is proposed, and the reason of the machining accuracy improvement by applying ultrasonic elliptical vibration is clarified theoretically. Finally, the effect of ultrasonic elliptical vibration cutting on machining accuracy is verified experimentally by utilizing an ultrasonic elliptical vibration cutting system.

In this paper, a new type of the offshore wind turbine installation equipment is proposed, which has 6 sets of intelligent legs. Each intelligent leg consists of two-UPS and one-UP. Based on the theory of the parallel mechanism, the mechanism of this offshore wind turbine installation equipment with 6 sets of intelligent legs is constructed. We take a set of the intelligent leg for analysis and conducted kinematic analysis and dynamic analysis on the offshore wind turbine installation equipment. Finally, by studying the fuzzy reliability of the kinematic accuracy of a branch, the reliability model of the whole mechanism of the installation equipment combined with the characteristics of installation process is established, and the calculation of the fuzzy reliability of the kinematic accuracy of the whole mechanism is carried out.Copyright © 2014 by ASME

In this paper, a kind of 6-degree of freedom parallel earthquake simulator is proposed, which has 28 -input, two types of the branches and the redundant and fault-tolerant actuators. Based on the theory of the parallel mechanism, the mechanism of the 6-degree of freedom parallel earthquake simulator with 28 -input and the redundant and fault-tolerant actuators is constructed. The kinematic model of the earthquake simulator is established by D-H method. The kinematic simulation and the dynamic simulation of the earthquake simulator are carried out with ADAMS software. Finally, FEM model of the earthquake simulator is given and the modal analysis of the earthquake simulator is made with ANSYS software.Copyright © 2013 by ASME

In this paper, a new type of the positioner is proposed, which has with dual-drive and dual-screw. Comparing with the positioner of the traditional gear transmission system, the positioner with the new mechanism has less power and less work space. Based on the designing requirements, we optimized the dimensions of the mechanism of the positioner, and carried out the kinematic and dynamic analysis of the positioner. The strength and the rigidity of the positioner are analyzed by the use of FEM. Finally, according to fuzzy mathematical theory, the reliability of the mechanism motion of the positioner is studied.Copyright © 2012 by ASME

In this paper a novel orthogonal 6-DOF (Degree Of Freedom) parallel robot with redundant actuation is studied as an earthquake motion simulator. Taking the practical simulation of earthquake waves into consideration, we firstly analyze the general characteristics of natural earthquakes. Complexity and variety of seismic waves, 3-dimension and multi-DOF movement and strong devastating force are regarded as their three obvious features in this article. Based on the characteristics of this novel orthogonal 6-DOF parallel mechanism with redundant actuation and the features of earthquakes, the feasibility of using this parallel robot as an earthquake motion simulator is analyzed. In order to simulate earthquake motion by using the parallel robot, its unambiguous kinematics and dynamics models are derived in details. The control system of the proposed earthquake simulator is developed based on the PXIbus development platform. A typical three-direction earthquake motion, the El Centro earthquake, is simulated on the end-effector of the parallel robot using its mathematical models and control system. Three main motion parameters of simulated seismic waves, displacements, velocities and accelerations are measured respectively. The experimental results show that this equipment is appropriate for using as an earthquake simulator.

There are short of detection methods during grinding process at present. In this paper a new online detection method based on pattern recognition was studied. Firstly, the machine vision measurement system was designed according to the characteristics of grinding machining. The work piece or grinding wheel image was sampled at a certain position in order to avoid sparks influences. The factors which influence detection precision were also investigated, and also gave some solving methods. Finally, lots of experiments were done to test the system performance and its precision. From the experiments analysis, the detection precision of the system is less than 2mum. It can meet the detection requirement of accurate grinding