Research On Loading Manipulator System Based On Vision Positioning

Mechanical engineering is an important of modern industry.It is widely used in national defense, construction, urban construction, environmental protection, transportation, energy industry and material industry etc.Caterpillar shaft is an important part of the caterpillar type machine. The processing of the caterpillar shaft must be after quenching and tempering treatment to get good mechanical properties.Now the environment of the caterpillar shaft heat treatment is harsh and the level of the caterpillar shaft automatic production is low. So the working efficiency of the caterpillar shaft production is not high and the handling time after the caterpillar shaft quenching is not enough. It is very important to develop a set of automated moving equipment to strictly control the preparing time between quenching and tempering, to ensure the caterpillar shaft quality and to improve the efficiency of the whole process.In the background of caterpillar shaft automatic loading and unloading production line system, the paper firstly introduces the current development of robot and computer vision. Then the paper introduces the development status of robot vision and the commonly used visual processing method. The overall structure of the manipulator is proposed according to the requirement of the project and the key hardwares are selected.According to the problems in the process of loading and unloading and the characteristic of the workpiece, the whole structure of the manipulator be designed and a special gripper be studied. In addition to the handing function, the whole manipulator also have real-time monitoring functions of the positional relationship between the gripper and the workpiece, to prevent the collision; and when a deviation occurs between crawl offset center of the workpiece and the center of the gripper, the deviation will be detected and corrected timely. The grasping process can automatic complete rectifying a deviation.According to features that the industrial field is not conducive to using the calibration plate, a method of non-uniform calibration are put forward by use of workpiece on the basis of the traditional calibration methods. According to the location the workpiece appear in the visual region determine the interest visual range, namely the focus of visual calibration region. Determine the calibration point by matching the actual point of the workpiece coordinate and image coordinate, through a set of calibration point to complete the rapid calibration of the camera by using the local linear interpolation, and the camera are used to assist the manipulator system to complete the visual location of the workpiece.Build the test platform, software programming, through the experiment verify the feasibility of this method, and further analysis of the relationship between the number of calibration points and the position error in a same region of interest,. After statistical analysis of a large amount of data obtained by experiment, the workpiece to conform to normal distribution on nine interval in the workpiece box, consistent with the uniform calibration, verified the practicability of the system.