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A finite element model based on Abaqus/Explicit is built. Micro cutting mechanism of Al7075 with different cutting depth is simulated and analyzed. The simulation results show that if the cutting depth is more than 10μm, the chip is a kind of continuous curl. If the cutting depth is less than 10μm, the chip is a kind of feathery squeeze debris. When the cutting depth is very small (3μm), the shape of chips is just like discontinuous wrinkle. By contrasting the simulation results of cutting force with its theoretical values, they have the same result. The model of the chip prediction could achieve ideal simulation results.

This paper introduced a kind of micro/nanomotion platform. The platform mainly includes 12 flexible hinges, piezoelectric ceramic driver (PZT), motion platform (loaded platform), pre-tightening force adjusting screw and so on. The orthogonal experiment method was used to the output displacement of the micro/nanoplatform. The relationship among the voltage, pre-tightening force and output displacement of the platform was analyzed. The factor level table of the output displacement was produced. The experimental system was established by Laser interferometer and pressure sensor, then the output displacement was obtained when the voltage ranges from 0V to 150V on the condition of every force (20N, 40N, 60N, 80N and 100N). The experimental result lays the foundation for the regression analysis of the output displacement of the platform.

The Fast Tool Servo (FTS) is widely used for the machining of micro-structures, especially for optical micro lens array. The working principle of FTS is that a voice coil motor or a piezoelectric (PZT) actuator is used as the driving elements, and the flexure hinges are developed as the guide mechanisms. In addition, an optical encoder is applied to measure the displacement. However, the existing design of FTS is too complicated and expensive. One reason is that the stroke of the FTS for the fabrication of optical micro lens array is only a few hundred micrometers, while its precision reaches to nanometric range, thus the optical encoder in not applicable. On the other hand, there exists sluggish and creep for piezoelectric materials, which makes the control of displacement difficult. This paper develops a displacement sensor embedded voice coil motor. In the design, the driving element is ampere force of the voice coil motor which is a linear ratio to the input current. Both the two covers are thin plates which serve as compliant mechanism by supporting the deformation at the Radial direction and provide linear stiffness in the axial direction. Therefore, the output displacement is proportional to the ampere force. The existence of external force affects the actual displacement, an embedded capacitor serves as displacement sensor will detects the real displacement, and the external force can be estimated by the current and measured displacement, which makes the motion control easy. At the same time, a multiphysics model of the developed FTS is built in this study by using finite element method and the displacement control under different cutting force is studied. The experimental results show that the developed FTS is efficient for achieving short stroke with high precision.

The optical structure has a large number of micro-structures, which has multiple arrays, complex free-form surface features. But those can not be achieved the requirements with traditional turning and grinding processing, it require to use high-frequency and micro-feed to get ultra-precision machining precision. After creating the 3D digital model of micro-displacement platform using Pro/Engineer, and analyzing the motion and the force, the paper studies the influencing factors about the rigidity and acceleration and explores the motion characteristics of the micro-displacement platform in the high-frequency control, and it the establishes the corresponding dynamics equation. The stiffness and linearity data is accessed after the micro-stage is simulated used by Admas and Ansys software. According to the above data, the structure of micro-stage is optimized in order to meet the ultra-precision machining accuracy and the quality of the workpiece. The research takes advantage of the favorable conditions of the Nanofabrication Laboratory, and it has completed the physical production of the micro-displacement platform supported by the introduction of innovative R&D team program of Guangdong Province, those provide a reliable experimental conditions for future in-depth study.

This paper introduced a kind of fast tool servo (FTS). Base on in the frame rack, flexible hinge, piezoelectric ceramic driver, tool base, diamond tools and so on. Laser interferometer is used for displacement measuring of the fast tool servo. The structure simulation was done to the FTS and the nature frequency was obtained. The output displacement of FTS was measured by Laser interferometer. Four kinds of different sin wave sign were given and the frequency of driving voltage ranged from 10Hz to 400 Hz. The relation of the displacement and the driving voltage frequency and the relation of displacement and the driving voltage had been established by experiment.

It is a FTS with flexible hinge that can be replaceable. It includes flexible hinges, a movable block, piezoelectric ceramic driver and framework. The flexible hinge is installed on inner side of the frame, and the other side is connected with the movable block. The piezoelectric ceramic driver is installed in movable block, and its other end is installed on the end beam of the frame. There is a tool base in the front end of the movable block on which the diamond tools can be fixed. Under the support of the flexible hinges, the tool can move back and front driven be piezoelectric ceramic driver. Through the simulation analyses with finite element technology and experiment, it is certify that the design of FTS is successful and practical to further study.

t presents the parallel mechanism and variable acceleration control method, which is composed of slider, connecting rod, moving platform and linear guide etc. The motion platform is supported by three connecting rods through hinging, the other end of the connecting rods are respectively hinged with two sliders. Among them two pairs of connecting rod, two sliders and the moving platform formed a symmetric structure that is the so called Parallel Mechanism. The third connecting rod is parallel to one of two connecting rods, so that the two parallel connecting rods, slide block and the moving platform formed a parallelogram structure, it makes that the moving platform is always parallel to liner guiderail in the process of movement. By controlling the two sliders moving in the way of variable acceleration, it can make the trajectory curve, speed curve and acceleration curve of the moving platform are continuous, smooth, so impact and vibration of the moving platform is limited in the operation process.

Adopting high-speed line scan industrial camera, through window function of the software to capture interested areas scanning by linear structured light, through image processing algorithms and splicing technique to extract 3D feature information of the detected object surface, combined with the camera calibration technology, calculated the three-dimensional coordinates of the detected object, and real-time displayed intuitive pseudo color map, monitored picture signal and weeded out unqualified products. Compared with similar systems at home and abroad, the system are real-time pseudo color graphics display, open system and lower cost.

This paper introduced a kind of fast tool servo (FTS) that its stiffness is adjustable. Based on in the frame rack, flexible hinge, piezoelectric ceramic driver, tool base, diamond tools and so on, a spring assembly appendixes on. The spring assembly is consisting of spring rack, the sleeve, spring, and lock circle etc. Spring rack is fixed in front of the frame rack; there is a screw hole in the middle of the spring rack; there is also a screw outer side of the sleeve that mounted through the screw hole. The spring is installed inside sleeve; one end of the spring contacts with the bottom of the sleeve, and the other end contacts with the flexible hinge on frame rack. It can adjust the force of the spring that presses to the flexible hinge by rotating the sleeve. Through replaced the spring, it can makes stiffness of the FTS changed. It is verified that the device has the stiffness adjustable function through calculation and simulation.

According to the microstructure characteristics of the optical components surface, the paper designs a bridge right-angle flexure hinge driven by a piezoelectric ceramic. It meets the driving micro-displacement magnification requirements and solves the coupling problem in work. Using the calculation formulas of statics and calculation formula of bending moment, the thesis explores the motion law of piezoelectric ceramics with 1KHZ excitation frequency. Through the exploration of the factors of bridge flexure hinge angle stiffness and tensile stiffness, the mathematical model of input displacement and output displacement is established. Studying the theory about the elimination of motion process coupling, it excavates the function relationships of flexure hinge angle and magnification. And the relationship is unearthed among driving force of piezoelectric ceramic, the flexure hinge stiffness, cutting force and mass of cutter system. The paper establishes their mathematical model between the above elements and the output micro-displacement, and the theoretical result is calculated by Matlab. Finally, using Pro/Engineer 3D digital modeling and analysis of simulation results by Ansys, it is found that the error can be controlled in an acceptable range by comparing the theoretical results with simulation results. Through the above analysis, the theoretical design is found to be reliable and effective.

The Fast-Tool-Servo (FTS) is widely used for micro-structure manufacturing especially for micro optical lens. The working principle of FTS presented by Qiang Liu et.al is that, a voice coil motor and a piezoelectric（PZT） actuator are used as the driving elements, and two flexure hinges are developed as the guide mechanisms. However, vertical displacement jump happens when the flexure hinges are driven by a voice coil motor or a piezoelectric actuator. In this paper, a new amplified structure is presented, allowing the horizontal motion while reducing the vertical displacement jump. The working principle is that, the piezoelectric actuator is applied to a beam which has two flexure hinges, one is linked to the frame, and the other is linked to a tool holder which is situated through two parallel membranes. When the piezoelectric actuator deforms, the beam will rotate around the frame, while the displacement is amplified at the other end, causing the tool holder’s motion and the membranes are forced to bend, while the vertical motion is restrained by the membranes. As a result, the presented membrane based flexure structure is able to amplify the motion of the piezoelectric actuator. In addition, the vibration frequency of the membrane is easy to be adjusted by the preloaded force. It is important to know when the FTS is working at different frequency. The performance of the presented structure is analyzed by structural dynamics coupled with piezoelectric, and the parameters of the structure are optimized to remain linear relation between the tool holder and the piezoelectric actuator, while the vertical displacement jump is much smaller than the structure presented in reference.

This paper presents a manual moving and lifting worktable. This worktable consists of roof, base,cross frame, wheels, lifting device, wire driving two-way ratchet and parallelogram steering structure. It can do some action such as moving, turning and lifting through the manual operation for the application of warehouse, logistics, and indoor maintenance. The paper analyses the principle and structure of the worktable, especially on the design and work principle of two-way ratchet. The design is satisfied by built a real model.

This paper presents a two-dimensional movement and the one-dimensional rotating 3 DOF robot that can be used to pick up, delivery and place riveting column, thin axis (referred to as riveting column) and other parts, forming the assembly systems of riveting of sheet metal. In addition to the robot, the system also has moving table, clamp, a number of riveting column station and spin riveter etc. Moving table is equipped with the clamp, it can move in the X and Y directions, respectively. The clamp that fixed the sheet metal work-piece can move in Z-direction, which make it easy for assembling the riveting axis into the riveting holes on the work-piece. Robot can move along the Y axis and swing around the Z axis, make the nozzle that is in the end of manipulator move between riveting column stations and spin riveter, which pick up and place the riveting column. A number of riveting column station is used for store riveting column and sorting them. Spin riveter rotates while moving along the Z axis at the same time, by pressure and rotational force it completes the column riveting on sheet metal parts.