Chen Qingwei

A new Geometrical Method for the Inverse Kinematics of the Hyper-Redundant Manipulators

Aimed at the inverse kinematics of hyper-redundant planar manipulators, a new and simple geometrical method was proposed in this paper. The proposed method can obtain a optimal solution of the inverse manipulators with less computations. Some disadvantages of the existing methods were overcome by the proposed method. The proposed method can be applied to any planar manipulators with n-links serially connected by revolute joints. Finally, through a detail computing procedure for a planar manipulator with five joints, the effectiveness of the proposed method was shown.

Robust reliable control of switched uncertain systems with time-varying delay

This paper is concerned with reliable control problems for the switched uncertain systems with time varying delay. A method for designing robust reliable controller is presented by means of the multiple Lyapunov functions technique so that the energy-like functional does not have to decrease along the switching instants. The proposed controller is reliable in that it can guarantee the closed loop asymptotic stablility of switched delay systems in the case of the possible presence of failures of partial actuators. Delay independent results of the reliable controller design are presented in terms of Linear Matrix Inequalities (LMIs). Finally, a numerical example is given to illustrate the applicability of the proposed results.

Behavior Selection Mechanism of Two Typical Brain Movement Disorders: Comparative Study Using Robot

Parkinsons disease and Huntingtons disease are two typical brain movement disorders, both of which have been studied extensively for decades. Dysfunctions in the basal ganglia-a group of sub cortex nuclei in vertebrate brains-are generally considered to account for these two diseases. But what will happen if a robot gets Parkinsons disease or Huntingtons disease? Based on the concepts in behavior based robotics, this paper studied the behavior patterns of a real robot when it suffers such two diseases. The experiment results showed that the sick robot exhibited some symptoms of Parkinsons disease or Huntingtons disease to some extent. This study made explorations to mimic high level brain functions and casted light on designing more intelligent behavior selection methods in the future.

Dynamic Formation Control for Car-like Mobile Robots

For the formation problem of the car-like mobile robots, a dynamic coordinated control algorithm for multiple robots is proposed. Firstly, a model of trajectory tracking system for the follower robot is established through the virtual robot, which is generated according to the desired formation parameters of the leader and follower robots. Then the robots kinematics model is transformed into the chain form, and the Lyapunov function of the trajectory tracking system is constructed via the backstepping method. The trajectory tracking controller for the follower robot is obtained by making this Lyapunov function negative-definite. The formation control of the car-like mobile robots is realized in this way. A 3D simulation testbed is designed by the Microsoft Robotics Developer Studio 4(MRDS4), and the effectiveness of the proposed method is demonstrated through 3 sets of experiments.

A SRT-based path planning algorithm in unknown complex environment

Aiming to the robot path planning problem in the unknown complex environment, this paper presents an improved Sensor-based Random Tree (SRT) path planning algorithm. First, RRT and SRT path planning algorithms are briefly introduced. Then, an original algorithm which uses the real-time local information from robot sensors and the target tendency method to make the online planning is presented. The algorithm overcomes SRTs redundant branches and low efficiency by combining the nonholonomic constraint conditions and the candidate viewpoint optimization, on which improves SRTs planning efficiency, and guarantees its stability as well. Finally, simulated experiments are done on Player/Stage and MRDS platforms, and the results verified the reliability and effectiveness of the proposed algorithm.

Design of dual-PMSM synchronous control drive

To meet the demands of modern AC servo systems for high-power and high-precision, a new drive that synchronizing two Permanent Magnet Synchronous Motors (PMSM) is designed based on DSP (Digital Signal Processor) and CPLD (Complex Programmable Logic Device) in this paper. The structure of the dual-PMSM synchronous control drive is detailed described. The hardware circuits and the software with the function of synchronous control are also designed. The experimental results show that the synchronous control drive has good performance in terms of running reliably and tracking precision for synchronizing two motors. This device has a broad perspective for popularization.

A recursive design method of stabilization controller for the inertia wheel pendulum

Aimed at the stabilization problem of the Inertia Wheel Pendulum system, a recursive design method of stabilization controller is present. And a state feedback controller with explicit form was obtained. The stability of the closed loop system was analyzed by input-to-state stability. Finally, the effectiveness and performance of the proposed stabilization controllers for an inertia wheel pendulum system with parameters taken from a real-life model of the IWP is shown through simulations.

The review and implementation of multi-robot system simulation software

Compared to the single-robot system, the multi-robot system has more advantages and a broaden application aspect, and is becoming one of the hottest topics in Robotics. Furthermore, the simulation experiment is playing an important role in multi-robot system researches. This paper makes a good analysis and conclusion of the multi-robot system simulation software status quo, with an emphasis on the several present mainstream ones and the evaluation criteria. Then, based on the characteristics and requirements of the multi-robot system simulation experiments, the 3D simulation platform is developed in the Microsoft Robotics Developer Studio, aiming to the two typical tasks - Collaborating Transportation and Formation Patrol.

Observer design for MIMO networked control systems

The observer design is described for a class of MIMO networked control systems. Consider a MIMO networked control system within time-driven sensor nodes and controller node, the effect to the information transmission, which caused by network induced delay and data packet dropout, is analyzed firstly. And a observer is proposed to compensate the delay and packet dropout. Then based on separation theory, with the multi-Lyapunov functions and linear matrix inequality method, the sufficient condition on the asymmetric stability of the observer error system is given, together with the design approach of the gain matrix. Finally, a numerical example is given to validate the method.

A recursive design method of controller for the stabilization of the translational oscillator with a rotational actuator system

Aimed at the stabilization problem of the translational oscillator with a rotational actuator system, a recursive design method of controller is present. And a state feedback controller with explicit form is obtained. The stability of the closed loop system is analyzed by input-to-state stability. Finally, the effectiveness and performance of the proposed controllers is shown through simulations for the stabilization of the translational oscillator with a rotational actuator system which uses the same parameters that are taken from a real-life model of the TORA.