Design And Control Of The Mobile Manipulator For Biological Sampling

In recent years, the outburst of the emerging infectious diseases become morefrequent and the terrorist attacks using biological and chemical weapons become morecommon. As to assess the pollution range and verify the pollution source, samples of theatmosphere, soil and water in the targeted area should be taken and analyzed where themobile manipulator can play the role of human to take the samples in the front line,which will save the first responders from the harm of the environment. So thedevelopment of a mobile manipulator for chemical and biological sampling has greatpractical value. Aiming at the sampling requirement, the mechanical design of a5Rmobile manipulator is completed, as well as the sampling gripper and special designedquick change tools. The control system based on ROS is implemented and the samplingexperiment is conducted to verify the functionality of the system.Firstly, the sampling process is planned and the requirement is analyzed in detail.On the basis of the research of typical mobile manipulators around the world andconsidering the special requirement, the DOF and configuration of the manipulator ischosen and the mechanical design of the manipulator is completed. A quick changesampling scheme is designed and the sampling gripper, the sampling container,container installing base and the five special tools for deep water, surface liquid, sandysoil, pan soil and pick up object are designed.Secondly, the forward and inverse kinematics of the5R sampling manipulator isanalyzed. The workspace is pictured using Monte-Carlo method which is analyzed todetermine the motion range of each joint. As to get the greatest performance in thetargeted area, the planner3R manipulator is deeply looked into and the optimization ofthe sampling manipulator is completed with the parameters determined, the targetfunction established using the Jacobian matrix and several constraints built consideringthe sampling requirements.Next, the requirement for the control system is analyzed and the functionaldecomposition is finished based on which the framework of the software is establishedand specific implementation method is proposed under ROS. As for specific functionmodules, the PMAC and the robot interface program is implemented. The coordinatorprogram combing the trajectory interpolation, the kinematics is completed. The virtualplatform of the sampling manipulator is developed.Last, the hardware platform of the control system is established and thecommunication network is set up based on ROS with the hardware debugged from thebottom. On such condition, the sampling process is planned in detail and the sampling experiments for five sampling targets are conducted to prove the functionality of thespecial tools and the control system.