Due to the complex and varied substrate environmental characteristics of cobalt-rich crusts and hydrothermal sulfide survey area in deep sea,a composite wheeled mining robot with active and passive over-obstacle capacity is designed. The mining robot is composed of 4-composite wheels and an integral articulated sealed compressive tank frame.A static model of the composite wheels structure is set up in the typical over-obstacle condition,to obtain its main structural parameters affecting over-obstacle capacity.Using MATLAB toolbox,the composite wheels structural parameters are optimized for design,so that the over-obstacle capacity is improved.Considering the complex and varied substrate environmental characteristics in deep sea,dynamics model of the optimized composite wheeled robot is set up,the simulation analysis with ADAMS is performed,and dynamic characteristics curve and mechanical characteristics curve of the mining robot are obtained in over-obstacle process.Through designing prototype and testing its over-obstacle capacity,it is shown that the mining robot has strong over-obstacle capacity and transit stability in the complex and varied deep sea substrate environment.

A control system design method based on dynamic interpolation strategy is proposed to improve the motion control performance of rehabilitation robot.Firstly,the impaired-limb movement features are extracted with sliding standard deviation for a certain data samples,and the real-time physical state of impaired limb is acquired by fuzzy reasoning.Secondly,the appropriate interpolation method for motion control is recommended using dynamic interpolation decision-making mechanism.Finally,the position-based impedance control is adopted to carry out training exercise.The proposed method avoids the limitations of the conventional single-interpolation methods,and effectively integrates the characteristics of different interpolation methods.Experimental results based on WAMTM rehabilitation robot show that the designed control system with proposed method demonstrates better motion control performances under disturbances.

Most traditional single-legged hopping robots use state-based control algorithms in height control.Position sensor is used in these algorithms,which results in the complexity of mechanics and control systems.To simplify the system,a control algorithm based on time event is proposed,which only uses ground-touch switch.A dynamics model considering pneumatic features is developed,the characteristics of the control algorithm are analyzed through simulation,and its effectiveness is verified with a prototype robot.The simulation and experiment results show that the robot using the control method based on time event not only can ensure the same stable margin and convergence speed,but also has flexible adjustment ability of hopping height and a simple system structure compared with algorithms based on state event.

To solve the problem in the space robot's microgravity simulation experiment that lateral interference force/moment exists and the workbench is uneven,a high load capacity,high stiffness round aerostatic thrust bearing with circumferential and radial pressure-equalizing grooves is designed and manufactured,and its load capacity is modeled and numerically analyzed using deformational Reynolds equation.In order to validate the theoretical calculation results,simulation analysis using Fluent is carried out to get the load capacity characteristics,and the influence of the impact created by the high pressure gas on the load capacity is analyzed.Finally,an experiment about the bearing's load capacity characteristics is performed on the standard test platform,and the result is compared with the data of bearing without grooves.It turns out that the structure design and theoretical analysis are correct.

An efficient method for constructing an open 3D robot simulation environment is presented.Based on the platform of Matlab software,this method integrates the 3D solid design softwares such as Pro/E,Matlab Robot Toolbox and Matlab 3D visualization technology to construct a 3D robot simulation environment with good visualization and highly detailed model.Taking widely applied VA1400 arc welding robot as an example,steps of this method are presented in detail,including the construction of 3D robot model,data importation of solid model and 3D animation display of the simulation system.Thereafter,a high-level open robot simulation system with good 3D visualization is achieved.Snapshots and simulation graphs are presented,which prove the effectiveness of our method.

An adaptive coverage sampling algorithm is proposed for solving the dynamic and unknown ocean phenomenon by underwater gliders. Firstly, the criterion for optimal coverage sampling is defined based on the centroidal Voronoi partition of the sampling space. Secondly, recursive least square with forgetting factor is used to estimate the parameters of ocean phenomenon online. Finally, the distributed control law is proposed, which can guarantee the sampling network composed of underwater gliders to converge to the optimal sampling network config defined from the random initial state. The simulation experiment is carried out to show the effectiveness of the proposed method. The results show that the proposed adaptive coverage sampling strategy has a better performance in the sampling of dynamic ocean phenomenon.

A surgical planning scheme for robot-assisted celiac interventional therapy system is proposed.Through analyzing the surgical procedure,a physical model is presented to simplify the needle into an operation arm with a single globe hinge joint.The nonlinear equations with parameter are adopted to obtain the analytic description of the needle's workspace based on the study on the analytic description of the arm's collision-free reachable workspace boundary in robotics.The ribs and blood vessels in the abdominal cavity are described with third-order continuous differentiable super quadric surface equation.With numerical iterative continuation method,the unidimensional manifold of needle's collision-free reachable workspace boundary is solved,and the three-dimensional models are displayed with the Matlab toolbox.For the case that ribs and vessels exist in the abdominal cavity,the workspace boundary of the needle is successfully obtained.According to simulation results,the needle-insertion path will not collide with fraises such as ribs and vessels if the entry point is selected within the needle's workspace boundary.This paper provides an effective means for doctors to make successful surgery operation planning,solves the problem that the current system determines the entry point by doctors' own surgical experiences, and improves the efficiency and success rate of surgery.

A simultaneous localization and mapping(SLAM) algorithm based on the combined EKF(extended Kalman filter) of Sage-Husa adaptive EKF and strong tracking EKF is presented to solve the decrease of filtering accuracy of standard EKF when the statistical characteristics of noise are not accurate and the model builded can not match with the actual one completely.Firstly,the dynamic model,feature model and sensor measurement model of AUV(autonomous underwater vehicle) are set up.Then,feature extraction is implemented through Hough transform,and SLAM of AUV is realized with the combined EKF eventually.Simulation with trial data shows that the described method reduces the influence of both the time-variance of statistical characteristics of noise and the inaccuracy of model,and enhances the accuracy and robustness of SLAM system.

The system of a joint driven by PMAs(pneumatic muscle actuators) is a strong nonlinear time-varying self-balanced second-order system.Traditional control methods are difficult to overcome the conflict between the control accuracy, the regulating speed and the stability.A second-order active disturbance rejection control(ADRC) is designed,in which a third-order ESO(extended states observer) is adopted to estimate the non-modeling part and external disturbance in real time and to make the linear compensation for system.Meanwhile,the control efficiency is improved by a nonlinear feedback. On the premise of ensuring the stability,the adjusting speed and control accuracy is enhanced.The system's steady-state accuracy is less than 0.1°and the tracking accuracy is less than 0.5°.Even in the case of the unknown or partly known system model,the system using ADRC can still achieve a satisfactory control result.

When space robot is capturing an object,the disturbance force produced by interactive collisions may induce the robot arm dithering and distortion;moreover,it may also pop-up the target object away from the capture zone,which will lead to the failure of capturing operation.To solve this problem,the design of three-fingered space robot end-effector of Harbin Institute of Technology(HIT) is introduced firstly,and then the disturbance force produced by interactive collisions during the progress of grasping a target object is analyzed.A compliant grasp strategy is proposed to weaken the interactive collisions disturbance force,and a new structure of controller based on the combination of feed-forward compensation and fuzzy-sliding mode control is proposed.The deterministic disturbance,the linear part of the friction,and the part associated with end-effector's structure itself can be gained by modeling and off-line testing,which can be controlled effectively by feed-forward compensation,and the fuzzy mode control rules can compensate the external uncertain disturbance,nonlinear part of friction,grasp force and so on.Using satellite on-orbit self-servicing manipulator and three-fingered space robot end-effector designed by Harbin Institute of Technology,some grasp experiments are performed on micro-gravity platform. Experimental results show that the proposed strategy and the designed controller can effectively eliminate the disturbance force during grasping.