Control Technology, Based On The Vision Of The Six Degrees Of Freedom Manipulator

Manipulators with multi-degree of freedom play an important role in known environment owing to their characters, such as high-speed and flexible. However, they can't get external information independently, so the autonomous controlling of manipulators faces new challenge in unknown environment. With the development of the video and image processing technology, the appearance of the controlling technology based on vision provides a method which resolves the problem of the autonomous controlling of manipulators in unknown environment.A method to control manipulators based on vision is studied in this paper. The work is carried through on the PowerCube modular manipulator with six degrees of freedom. Making use of the feedback from the vision sensor, the actuator of the manipulator can aim at the target and snatch at it.First, the structure of the manipulator is analyzed. With the D-H method, the model of the manipulator's kinematics is set up. Based on the model, the equation of direct kinematics is deduced. A method which solves the problem of the manipulator's inverse kinematics is proposed. And the analytical solution of the problem of the manipulator's inverse kinematics is found. Meanwhile, the experiment is completed on the manipulator.Second, a method of picking up the target's feature from the image is researched. And with camera demarcating, a method to get the three-dimensional coordinates of the target with a camera is proposed. The methods used in the experiments are proved correct.Finally, a system to control the manipulator based on vision is designed. The software is illustrated from the perspective of the software structure, the flow chart and the user interface. Besides, a controlling experiment based on vision with a camera whose type is EVI-D100P is carried out on the PowerCube manipulator. The results have proved the correctness of the methods of inverse kinematics and target location.