Research And Design Of Full-Ocean-Depth Underwater Pan And Tilt Control System

The Full-ocean-depth operational Human-occupied vehicle is a major means for human beings to detect deep sea environment,as well as the core of marine engineering equipment technology.As a platform for mounting observation equipment such as cameras,underwater lights,laser rangefinders and the Pan-tilt is installed in the head of human-occupied vehicle,which is the key to obtaining high-quality underwater images.Based on the requirements of Pan-tilt operation in the Human-occupied vehicle,this thesis applies the techniques of robot control,mechanical design,automation,communication and image processing to research and design the Full-ocean-depth underwater Pan-tilt control system.Primary works have been done in following aspects for study:Research the background of Full-ocean-depth underwater Pan-tilt control system:Based on the research purpose of the Full-ocean-depth Pan-tilt mounted on the Human-occupied vehicle,the application background of the mobile Pan-tilt control technology is described,and the research achievements at home and abroad of Pan-tilt and its control system are investigated.Overall design and modeling of Full-ocean-depth underwater Pan-tilt system:According to the operation needs of the Full-ocean-depth underwater Pan-Tilt mounted on the Human-occupied vehicle,the overall functions and design requirements of Pan-tilt control system are clarified.The underwater Pan-Tilt mechanical structure is designed,and the Pan-tilt rotation mechanism is simplified to establish the inertial coordinate system and the Pan-tilt coordinate system.The forward kinematics modeling method is used to describing the motion space of the underwater camera installation position.The second type of Lagrangian method is used to derive the Pan-tilt dynamics model to describe the correspondence between structural parameters,output torque and velocity.Hardware design of the Full-ocean-depth underwater Pan-tilt control system: Inorder to meet the underwater Pan-tilt function needs,the modular design method is used to subdivide the control circuit board into the main control module,communication module,servo control module and so on.Develop a communication scheme in which the control terminal indirectly accesses the outboard CAN bus node through the Bluetooth technology to maximize the in-cabin communication interface and space resources;The Elmo Gold Twitter servo drive,DC brushless motor and DC reducer are used to form a servo control system to meet the precise position control characteristics of the Pan-tilt control system.Software design of the Full-ocean-depth underwater Pan-tilt control system: The Pan-tilt control protocol based on the BLE Bluetooth application layer is formulated to realize the communication function of each node.In order to realize network management function of CAN Slave nodes,this thesis impies CANopen application layer protocol on the hardware platform of servo control system.The lower machine software of servo control system is developed by STM Cube MX,Keil and Elmo Studio to realize the functions of Pan-Tilt attitude precise control and attitude manual fine adjustment.Android mobile control terminal software and display platform software use Java and C# respectively to development a good human-computer interaction between the lower computer node and the upper control terminal.Research and implementation of Full-ocean-depth underwater Pan-Tilt tracking technology: In order to solve the problem that the underwater Pan-tilt manual tracking mobile target is difficult to operate,the moving target region is obtained using an image processing technique based on background difference image recognition and color feature matching based on the mean shift algorithm.The minimum circumscribed rectangular poid coordinates of the target area are extracted using the Graham operator.According to the distance between the poid and the image center,the rotational direction and the rotational speed control amount are obtained,so as to realize real-time tracking of the moving target and improve the intelligent level of Full-ocean depth underwater Pan-tilt control system.