| Teleoperation system with master-slave robot control at the core can be complex manipulated in uncertain or extreme environment (such as space, seabed, radialization, battlefield, etc.). The quality of operation is correlation with the ability of getting information (such as force, vision, etc.) about the slave side. The dynamic reciprocity between robot and operated object can be felt by teleoperation system on account of the force telepresence and video telepresence, which make the operator accomplish complicated and exact operation. Nowdays the research of technology related with telepresence is gaining greater attention.The theory of telerobotic system with telepresence is that telerobot working on spot is controlled by an operator with force feedback joysticks at safe location. There are video system and the sensors which are used to measure the hardness of the grabbed object and the resistance in the telerobot. Moreover, the image of on spot is transmitted to the screen in front of the operator by video system. In the sametime, the hardness of the grabbed object and the resistance in working can be judged by the feedback force of the joysticks. The working efficiency is improved greatly by such working of the prompt of highly telepresence. If used in rescue, this system will take less time. In the system, vision telepresence can provide most information for teleoperations, it is of great help for the human operators'cognition to the environments being operated. When robots contact the environment and only vision telepresence is provided, human operators cannot acquire the real sense.Only with the guidance of force telepresence can human operators accomplish these complex and fine tasks. Experiments on teleoperation systems also indicate that force and tangency senses can greatly enhance the efficiency and accuracy of teleoperation systems. Due to these, force telepresence may provide great help forteleoperation systems, and it can greatly enhance manipulation performance.In this paper, we have set up a telerobot system hydraulically droved with force feedback which is called two-DOF bilateral servo system after analyzing the telerobot systems with telepresence, especially those with force telepresence in home and abroad. The system has a symmetrical structure, whose master and slave subsystem is the same in form. To speak of the function of this robot system, it mainly comprises electron hydraulic proportional control subsystem, bilateral servo control subsystem. We have discussed the structures and realization of the functions of all subsystems at length built on those mentioned above.Aim to the problem of bilateral servo control strategy and position control of telerobot with force feedback existing in the telerobot field all over the world, we adopted a new control strategy after analyzing the old ones. And then, we designed a fuzzy-PID controller to control the telerobot system. Compared with the commen PID controller, the fuzzy-PID controller could change its parameters on line. We have validated that the new control strategy is feasible and the fuzzy-PID controller is better than commen PID controller when we did experiment on the two-DOF telerobot system hydraulically droved with force feedback.The main achievements of the research are presented as follows:1. We have set up a two-DOF master-slave telerobot system with force feedback based on electron hydraulic servo control system and it has the capacity of teleoperation, high precision position control and force feedback. The establishment of this system provide practice according for establishment of more complex teleoperation system.2. We have adopted a new bilateral servo control strategy to control the telerobot system. This strategy could make the manipulator control the position of slave side betimes, and at the same time, the manipulator will feel accurate dynamic reciprocity between robot and operated object with high prompt by force feedback. This could also avoid impact of force feedback. The result from experiment shows that this new strategy is feasible and reasonable. The research on new strategy will provide a new direction for the methods of bilateral servo control.3. We have designed fuzzy-PID controller for both master side and slave side of electron hydraulic servo control system. First, we designed a commen PID controller with the mothed of testing, and get its three parameters. And then, we designed a fuzzy-PID controller to control the telerobot system. Compared with the commen PID controller, the fuzzy-PID controller could change its parameters online. The result from experiment shows that fuzzy-PID controller is better than commen PID controller to control the system.4. We have used a new joy stick designed by construction robot laboratory of Jilin university in the two-DOF master-slave telerobot system. The new joy stick is good in rigidity, and have a good effort in force feedback. It is superior when compared with other joy stick. It can satisfy the need of master-slave telerobot system with new bilateral servo control strategy.The electron hydraulic servo master-slave telerobot system with force feedback which is researched in the paper could make manipulator feel dynamic reciprocity between robot and operated object with high prompt by force feedback, it will provide practice reference for more complex teleoperation system built in the future. The new bilateral servo control strategy and fuzzy-PID controller applied in master-slave robot systems have theoretical and practice meaning, it will provide valuable reference to the technique of master-slave telerobot system. |
PDF Full Text Request