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A three-DOF (degree of freedom) planar robot completely restrained and positioned parallel pulled by four wires was studied. The wire driving properties were analyzed through experiments. The restrained three-DOF planar platform was established based on slippery course and bearing, and dSPACE real-time control system was used to perform the platform’s motion control experiment on robot. Based on the kinematic equation and mechanical balance equation of moving platform, the stiffness of the robot system was analyzed and the calibration scheme of the system considering wire tension was put forward. Position servo control experiments were carried out, position servo tracking precision was analyzed, and real-time wire tension was detected. The results show that the moving error of the moving platform tracking is small (the maximum difference is about 3%), and the rotation error is large (the maximum difference is about 12%). The wire tension has wave properties (the wire tension fluctuation is about 10 N).

During rehabilitative training, a 3-DOF wire-driven parallel robot driven was designed to coordinate and control the trainer pelvis movement. Based on the force balance equation of the end-effector, the stiffness problem about the robot system was analyzed and one kind of force/position parallel control strategy was proposed that the position loop would realize the end-effector motion trajectory, and the force loop would control the wire tension. The experimental results have shown that the robot systematic stiffness is related with the wire tension and can be changed to realize the compliance control of the robot system by adjusting the wire tension.

Path planning for mobile robot is a kernel problem in the robot technology area, with the characteristics of complexity, binding and nonlinearity. On account of global path planning for mobile robot in static environment, this paper discussed a method of combining ant colony algorithm and genetic algorithm. After completing a cycle of ant colony algorithm, two paths ants walked were randomly selected, and these two paths were further optimized genetically on the basis of certain crossover rate, if more optimal paths were obtained, the pheromone would be released in the more optimal paths, by this method the diversity of solution could be increased and solution speed be improved. The simulation result has verified the effectiveness of the proposed method.

A robot system is present for the wind turbine blade grinding work. The robot is a mobile manipulator equipped with a grinding tool. In order to realize the compliant control of the operation force, a robust impedance controller is present in the presence of coupling factors between the mobile platform and manipulator, modeling uncertainties and existing bounded disturbances. The proposed control strategies guarantee that the system motion converges to the desired manifold and the desired constraint force. Simulation experiment has been done and the experiment results show that, the presented control method can realize the robust control of mobile manipulator, and thus show the effectiveness and correctness of the designed controller.

A mobile grinding robot is present here for the wind turbine blade grinding work. The robot is a mobile manipulator equipped with a grinding wheel. A mobile manipulator robot is built up with a mobile platform and a robotic arm mounted on it. The dynamic model of the robot is built, and the dynamic model of the two subsystems is derived from it, so the dynamic coupling items can be deduced. In order to discover how the coupling force influence the robotic manipulator, the SimMechanics model of the robot is built up and the simulation research is carried out by the built model. The results show the influence of coupling force on the manipulator.

There have been more and more types of electromechanical products which is detected and controlled with computer aided techniques, and also they have been more and more automatic. In order to learn and design a system to measure and control electromechanical products quickly, this paper developed a comprehensive test-bed to measure and control parameters. It combines VC++6.0 programming environment, MATLAB and PCL-818HG data acquisition card. This thesis introduced how to examine the displacement, rev, temperature, stress and the scheme of hardware composition to control the rev of engine. It also introduced the multi-threaded programming of VC++6.0 and the development methods of establishing link libraries between MATLAB and PCL-818HG. There were some applications as well.

In order to simulate the gait of human walking on different terrains a new robot with six degrees of freedom was proposed. Based on sand bearing characteristic compliance control was introduced to control system in horizontal and vertical movement directions at the end of the robot, and position control in attitude. With Matlab/Simulink toolbox, the system control models were established, and the bearing characteristics of rigid ground, hard sand, soft sand and softer sand were simulated. The results show that 0, 0.62, 0.89 and 1.12 mm are the maximal subsidences of the four kinds of ground along the positive direction of x-axis, respectively, and 0, −0.96, −1.99 and −3.00 mm are the maximal subsidences along the negative direction of x-axis, respectively. Every subsidence along y-axis is negative, and 0, −4.12, −8.23 and −12.01 mm are the maximal subsidences of the four kinds of ground, respectively. Simulation results show that the subsidence of footboard points to inferior anterior in early stage of stand phase, while points to posterior aspect in late stage. The subsidence tends to point to posterior aspect in the whole. These results are basically consistent with the gait characteristics of human walking on sand. Gait simulation of the robot for human walking on sand is achieved.

In this paper, multi-legged walking machine is simplified as one leg, which the whole machine is constructed by the modularization configuration of the legs in an axisymmetric way. Consequently, the control of one leg and its trajectory planning is the significant part for multi-legged walking machine. This paper, according to the structure of the walking machine's leg with 3-DOF open chains, calculates the terminal track of the leg using the principle of kinematics and presents a foot's controller based on dSPACE. In order to obtain the optimization of the foot's track, the three-cubic spline algorithm is considered. Depending on the model of the control system in Matlab, the paper provides a semi-physical simulation for a real leg using dSPACE. The feasibility of the planned track is demonstrated and the PID parameters have been adjusted.

An Ocean Casing Pipes Centering Equipment is designed and implemented. Utilizing the equipment, two casing pipes can be fastened together by means of welding. The equipment can automatically carry out clamping and centering two casing pipes, and then the butt welding is conducted at their adjacent ends. In the development of this equipment, some advanced means, such as digital modelling and FEA (Finite Element Analysis), are taken full advantage of. First, all the parts’ 3D models are built with Pro/Engineer. Then, those digital parts is assembled in Pro/E assembly environments. Meanwhile, assembly interference detection is executed. Furthermore, by means of universal finite-element software，the finite element model is constructed. The strength and stiffness of the structure is calculated and analyzed so that the faults of the equipment can be found out in design stage. Through repeating this designing and verifying course, the structure of the equipment can be improved.

A robust compensation control is proposed as anapproach for the robust motion control of a mobilemanipulator service robot comprising a mobile platform with atwo-link arm mounted on top of the platform. Considering thecoupling disturbance between the platform and themanipulator, nominal model of service robot is built, computedtorque and proportion-differential (PD) feedback controlmethod is presented, non-linear feedback is used to decouplethe control system. Aiming at the modeling uncertainty andexisting uncertainties disturbances, compensation is adoptedfor the built control law. Lyapunov method is adopted todetermine the compensation item, and by these, the robustmotion control of the mobile manipulator service robot isrealized. Simulation experiment had been done for the mobileplatform and the manipulator, experiment results show that,the presented control method can realize the robust control ofmobile manipulator service robot, and thus show theeffectiveness and correctness of the designed controller.