Fu Sheng Yu

Study on the Positioning Error of Turntable Based on Machine Vision System

This paper developed a turntable positioning error measurement system based on machine vision. The system consists of image acquisition devices, the image acquisition card, computer and data processing software and other components. Among them, the image acquisition devices consisted of two digital CCD cameras and two microscope objectives. The image acquisition devices capture images of fixture fixed on the turntable in horizontal and vertical direction. Then, the collected images are processed by adopting the filtering method, binarization method, edge detection method, calibration method and other steps. The high-accuracy measure of turntables positioning errors is realized, and the error histogram is drawn. Theoretical analysis and experimental results show that the method is correct and feasible.

Study on the Detection and Selection of Bearing Diameter Based on Machine Vision System

A new method and system for inspecting the bearing diameter is developed. The mechanical and movement control units, as well as its machine vision system, are designed. A precision measuring method based on machine vision system is developed to measure bearing diameter. Computer outputs the bearing edge contour and its three-dimensional coordinates after image processing software process the image of bearings which are collected by CCD camera. The controller controls the operation of motor by ball screws and drives the movement of individual parts which can crawls the gripper in the three-dimensional coordinates. Inductive gage is used to measure bearing diameter. Besides, a technology roadmap of image edge character detection is analyzed .Gaussian filter is used to noise reduction of the image and canny operator is used to edge detection. Template match is adapted to the automatic recognition of bearing characteristics. The paper may be helpful to those who work on the same subject in future.

Study on the Double Pulse Laser Dynamic Electronic Speckle Measurement Based on FPGA

Speckle pattern interferometry can be used to measure he displacement, strain and vibration, surface deformation and surface roughness. And dynamic laser speckle measurement with high accuracy has been widely used in measurement of surface deformation. Tool breakage is the main bottleneck of high-speed intermittent cutting development, therefore, obtaining stress distribution of milling tools is a base of improving the tool design and tool life. Using a speckle measurement method of double pulsed digital based on FPGA, which involves the laser cutter, tools and CCD, transforms the high-speed dynamic measurement to quasi-static measurement. As a result, we can get two speckle images of front and back milling cutter surface and calculate the deformation ,strain and stress distribution of the tool surface with analysis.

Modeling and Simulation of High Speed Intermittent Cutting Based on the Finite Element Method

In order to study the distribution of the stress field in the high-speed intermittent cutting process, finite element model of high-speed intermittent cutting is established. Exponential material model of the constitutive equation and adaptive grid technology are applied in the finite element analysis software AdvantEdge. The material processing is simulated under certain cutting conditions with FEM ( Finite Element Method ) and the distribution of cutting force, stress field, and temperature field are received. A periodic variation to the cutting force and temperature is showed in the simulation of high-speed intermittent cutting. Highest value of the milling temperature appears in front contacting area of the knife -the chip.and maximum stress occurs at the tip of tool or the vicinity of the main cutting edge. The analysis of stress and strain fields in-depth is of great significance to improve tool design and durability of tool.

Winter Jujubes Automatic Sorting Equipment Based on Photocell

Combining optical-electric separation with mechanical separation, winter jujubes are successfully separated by the characters of unripeness, ripeness and the size of it. When jujubes are sent into a box that holds jujubes, motor drives belt and jujube pallet to carry jujubes on the photoelectric separator. The separator is designed based on photocell. Effective control of electromagnet is achieved by photoelectric sensor which is consisted of red LED, power amplifier and MCU. Then winter jujubes are separated through the characters of ripeness and unripeness. Mechanical separation is accomplished by leakage pipe for jujubes in the adaptor. So winter jujubes are separated through their size.

COM Component Based on Matlab Algorithm for Speckle Processing

As a non-contract optical measurement method in solid mechanics, the digital speckle correlation method (DSCM) has already been recognized as an excellent method for determining the surface deformation field in materials because of its outstanding features. In-plane displacement fields at the surface of objects under load are abstracted by using this method in this paper. And the corresponding maps of displacement fields are drawn to show deformation. The basic principle and mathematical model of gradient-based subpixel registration are briefly introduced for measuring subpixel displacement. COM component of this method is generated by using matlab7.1 through images of laser speckles. The COM component is called by Visual C++6.0 and the stand-alone application is generated. It is becoming easier to deal with image in Visual C++ by using this method. Then more time and energy will be spent on the algorithm. The development cycle of the algorithm is speeded up and efficiency of the application is improved.

Effect of Working Parameters on the Damage of Ladder Impact Drill

The step face of the large-scale ladder impact drill is easy to generate fracture damage. The unreasonable working parameters are an important factor for the fracture damage in addition to the irrational structure. In this paper, three working parameters consisting of drill impact height, impact frequency and impact stratum for damage are studied from two perspectives of theoretical analysis and finite element analysis.

Structure Optimization of Large-Diameter Percussive Drill

The second and the third end faces of the tube support plate of the large-diameter percussive drill are prone to fracture. The structure optimization of large-diameter percussive drill is carried out in this paper. The fully closed structure is turned into semi-closed structure. The reinforcing rib is arranged. With a drop test analysis, the optimized structure can effectively reduce the stress of the drill.

Study on Multi-Objective Optimization Design of Planetary Gear Reducer

Various elements in planetary gear reducer design are discussed. A multi-objective optimization model is created. The model requires the minimum volume and the maximum contact ratio. The method of multiplication and division is used to solve the multi-objective problem, and the method of feasibility enumeration is used to handle the discrete variables. The results show that the optimal solution meets the actual requirements.

Computer Simulation of Fracture Damage for Large-Diameter Percussive Drill

A large-diameter trapezium percussive drill modeling is made by finite element modeling software and a computer simulation study of the drill is carried out in this paper. By a drop test analysis, the stress changes of each trapezoid faces is showed and the the larger stressed places are found out in this paper.The larger stressed places are easy to be fracture damaged.The beneficial theory basis will be provided by this simulation for the structural optimization of large-diameter percussive drill.