The optimal design problems of the lunar rover with the called suspension was introduced in this paper.Based on the analysis of the traveling mechanism and obstacle-navigation task requirements of the rover,the performance evaluating indicators of Rocker-Bogie was proposed,and four aspects are included.For the performance evaluating indicators,the multi-targets optimal design for the Rocker-Bogie has been carried out.The simulation results show that the mechanism parameters achieved from the optimal design can improve the traveling mechanism and the obstacle-navigation performance of the lunar rover effectively,providing the systematical design of the rover body with theoretical basis.

Highly accurate and fairly complicated tasks remotely via the Internet by teleoperation were available for expertise individuals today. But several obstacles still exist, ranging from human-computer interfacing and overcoming random time delay to task synchronization and human-robot interaction. This paper provides a new method on these challenges and some experimental results were obtained. Particularly, with the assistant of virtual force and QoS technique, the stability of teleoperation systems is guaranteed even under random network delay.

This paper presents a modeling method called "Wheel-Center Modeling" for kinematics of a wheeled mobile robot that moves on uneven terrain. The technique is verified by analyzing the special locomotion characteristics of the multi-rigid body and wheels of a wheeled mobile robot. A six-wheeled mobile robot with the called "Rocker-bogie" suspension has been modeled by using this method. The proposed method was verified by simulation where the robot moves on a flat plane.

A general method of kinematical modeling for all-terrain mobile robots is proposed.The robot is treated as a series-parallel multi-rigid body system.A series sub-system is formed from each wheel-terrain contact point to the robot body through compliant joints.Planar slips including forward slip,side slip and steering slip are considered by building instantaneous coordinate frame at each wheel-terrain contact point,and a closed velocity chain is developed for each series sub-system.In each closed velocity chain,the velocity relationship between the rigid body motion of the robot and the steering,and driving rates of the wheels can be directly written out at the axle center of each driving wheel.The whole kinemat ics equation of the robot body can be achieved by combining the velocity equation of each closed velocity chain.By using this kinematic s modeling method which considers both planar slips of each driving wheel and the effects of terrain profile,velocity equations can be easily developed for an all-terrain mobile robot.As long as the structure parameters of the robot are known,the kinematical equations of the robot body will be easily achieved,and also the forward and inverse kinematics are convenient to solve by using this method.The example of applying this method to a six-wheeled all-terrain mobile robot shows its merits of generality,definite physical meaning and concise derivation process.

Mixed-integer linear programming (MILP) for trajectory generation of mobile robot suffers from nonlinear constraints due to complex obstacle contours and dynamic environment. In this paper, relative velocity coordinates (RVCs) are proposed for solving the target pursuit and multiple-obstacle avoidance (TPMOA) problem. In the proposed RVCs, nonlinear constraints can be inherently described as linear inequalities, which allow MILP to be utilized to find the optimal trajectory satisfying the linear inequalities. The complexity of obstacle contour does not increase the computational load of the proposed approach. Simulation results are presented in comparison with those of evolutionary algorithm (EA), showing significant improvement in a number of aspects.

针对直线位姿估计问题分析了量化误差的传播特性,并以闭式解的形式建立了位姿估计结果受图像量化误差影响的数学模型.同时,在分析量化误差传播特性的基础上,给出了直线的选线方法.最后,确定了最优直线配置,提高了位姿估计精度.

This paper analyzes a kinematics model for a WMR(wheeled mobile robot) traversing a 3-D uneven terrain.A new kinematics model for WMR is deduced with velocity projection.Based on virtual reality,a virtual roving system for WMR is realized with VC++ OpenGL.With its strong interactive and real-time characteristics,the system provides the planetary exploration rovers with a verification platform for virtual navigation and teleoperation.

Mixed-integer linear programming (MILP) for trajectory generation of mobile robot suffers from nonlinear constraints due to complex obstacle contours and dynamic environment. In this paper, firstly, we introduce a relative velocity coordinates MILP (RVCs-MILP) for solving the nonlinear constraints problem in the trajectory generation of the target pursuit and multiple-obstacle avoidance (TPMOA). The computational load of the RVCs-MILP does not increase with the complexity of obstacle contour but only relates to the number of the obstacles. It can be applied in real time when the number of the obstacles is small. For the large numbers of obstacles avoidance, further, we propose an IHDR based online learning mechanism. It sets up a "scenario-action mapping" knowledge base by continuously offline training and online updating. For a trajectory generation task, it will search a best match path of the current state in the knowledge base according to the external environments and the state of the robot in real time. Simulations are presented in comparison with the evolution algorithms (EA) and IHDR. The former shows significant improvement in a number of aspects. The latter confirms the validation of the proposed IHDR methods.

Focusing on rough terrain mobility and security problems,this paper outlines the literatures mainly related to the modeling and control of all-terrain mobile robots from the aspects of robot modeling,wheelterrain contact,wheel slip,traction control and stability control.Meanwhile, the current research status,especially the latest research progresses,is analyzed in this work.At the end,this paper gives a discussion on the development trends of all-terrain mobile robots.

The reconfigurable modular robot has an enormous amount of configurations to adapt to various environments and tasks. It greatly increases the complexity of configuration research in that the possible configuration number of the reconfigurable modular robot grows exponentially with the increase of module number. Being the initial configuration or the basic configuration of the reconfigurable robot, the center-configuration plays a crucial role in system's actual applications. In this paper, a novel center-configuration selection technique has been proposed for reconfigurable modular robots. Based on the similarities between configurations' transformation and graph theory, configuration network has been applied in the modeling and analyzing of these configurations. Configuration adjacency matrix, reconfirmation cost matrix, and center-configuration coefficient have been defined for the configuration network correspondingly. Being similar to the center-location problem, the center configuration has been selected according to the largest center-configuration coefficient. As an example of the reconfigurable robotic system, AMOEBA-I, a three-module reconfigurable robot with nine configurations which was developed in Shenyang Institute of Automation (SIA), Chinese Academy of Sciences (CAS), has been introduced briefly. According to the numerical simulation result, the center-configuration coefficients for these nine configurations have been calculated and compared to validate this technique. Lastly, a center-configuration selection example is provided with consideration of the adjacent configurations. The center-configuration selection technique proposed in this paper is also available to other reconfigurable modular robots.

In this paper, the formation control and obstacle avoidance problems are dealt with a unified control algorithm, which allows the follower to avoid obstacle while maintaining desired relative bearing or relative distance from the leader. In the known leader-follower robot formation control literature, absolute motion states of the leader robot are required to control the followers,which may not be available in some environments. In this research, the leader-follower robot formation is modelled and controlled in terms of the relative motion states between the leader and follower robots. The absolute motion states of the leader robot are not required in the proposed formation controller. Furthermore, the research has been extended to a novel obstacle avoidance scheme based on sensing the relative motion between robot and obstacle. Experimental investigation has been conducted using the platform consisted of three nonholonomic mobile robots and computer vision system, and the results have demonstrated the effectiveness of the proposed methods.

可重构模块机器人具有多种构形以适应不同环境和任务的要求, 构形的多变增加了构形研究的难度. 在可重构模块机器人的众多构形中, 中心构形作为可重构模块机器人的首选构形或基准构形, 对系统的实际应用有重要参考价值. 文中提出了一种在所有构形中选择一个中心构形的方法. 根据构形之间可以相互转化的拓扑特征, 利用网络图中的基本思想和原理对可重构模块机器人的构形进行建模; 相应定义了构形转换耗值矩阵和构形中心因子, 根据最大构形中心因子可以对中心构形进行选择. 以中国科学院沈阳自动化研究所研制的三模块可重构机器人AMOEBA-I为例, 利用仿真计算的结果对机器人9种构形的中心因子进行计算和比较, 验证了该方法的可行性. 最后根据构形邻接数, 给出了中心构形选择方法的应用举例. 此方法还可以适用于其他可重构模块机器人系统中心构形的选择.

In this paper, we study the problem of modeling and controlling leader-follower formation of mobile robots. First, a novel kinematics model for leader-follower robot formation is formulated based on the relative motion states between the robots and the local motion of the follower robot. Using this model, the relative centripetal and Coriolis accelerations between robots are computed directly by measuring the relative and local motion sensors, and utilized to linearize the nonlinear system equations. A formation controller, consisting of a feedback linearization part and a sliding mode compensator, is designed to stabilize the overall system including the internal dynamics. The control gains are determined by solving a robustness inequality and assumed to satisfy a cooperative protocol that guarantees the stability of the zero dynamics of the formation system. The proposed controller generates the commanded acceleration for the follower robot and makes the formation control system robust to the effect of unmeasured acceleration of the leader robot. Furthermore, a robust adaptive controller is developed to deal with parametric uncertainty in the system. Simulation and experimental results have demonstrated the effectiveness of the proposed control method.

In order to implement the rapid reconfiguration of reconfigurable assembly system, based on analysis of traditional control systems, a hybrid architecture based on the multi-Agent systems was proposed, which integrated the advantages of hierarchical and distributed architecture. The proposed architecture was with low complexity, powerful robustness, easy maintainability, scalability, and reusability. Conforming to the Foundation for Intelligent Physical Agents (FIPA) standards, all kinds of Agents in the architecture were realized on the software development platform of Java Agent DEvelopment framework (JADE).

An artificial potential (AP)-guided evolutionary algorithm (EA) scheme for target pursuit in dynamic environment with multi-obstacles existence is proposed. The AP works as a guidance for the EA path planner by limiting the searching area around the potential field. An optimal trajectory is obtained with respect to the search area. The demonstration shown is one vehicle chasing one moving target while avoiding several moving obstacles. Extensive simulations are conducted to demonstrate the great improvements after integrating AP on the efficiency, the convergence and the real-time implementation. Also it solves the local minimum problem to a great extent in such circumstances.

flexible anthropomorphic 7-DOFrobotic armforamobile humanoid robot.The kinematics ofthearm suchas workspace, singularity, thenumberandphysical nature ofself-motion are presented. The concepts and methodology oftheinverse kinematics baseontheself -motion ofthearmaredescribed. Bythis methodthetaskandmotion scheduling cansimply be done.Theformulations ofdynamics andthedynamic effect duetothearm'sdeadweight wereanalyzed.

Stereo-vision plays an important part in planetary exploration. A high-precision calibration method is introduced for such system, which uses wide-angle lens. It makes use of planar homography constraint to estimate intrinsic and extrinsic parameters. On the basis of this initial guess, an optimization scheme is used to minimize a new cost function, 3D reprojection error sum. All calibration parameters of two cameras are globally optimized simultaneously with genetic algorithm (GA). Both simulation and real image experiment results show this scheme have much higher precision than traditional methods

For wheel-based humanoid robot, the dynamic stability is also an important question just like for biped robot. This paper unites the new recursive Newton-Euler method for dynamic modeling and the ZMP concept and then obtains the ZMP model of the robot. The merit of this model is that it is a function of the position, velocity and acceleration of joints in joint space and easier to realize realtime control due to less calculation. Calculation and simulation show that the waist motion takes the main effect on the dynamic stability of the robot. Using the compensation of motion of the waist, the robot can realize dynamic motion. This paper also presents the concepts of the valid stable region and stable degree for the wheel-based robot.

We have developed a highly flexible anthropomorphic 7-DOF robotic arm for a mobile humanoid robot. The kinematics of the arm such as workspace, singularity, the number and physical nature of self-motion are presented. The concepts and methodology of the inverse kinematics base on the self-motion of the arm are described. By this method the task and motion scheduling can simply be done. The formulations of dynamics and the dynamic effect due to the arm's dead weight were analyzed.

In this paper, the problem of formation control of robotic vehicles is studied. For a general formation (path, tree, or net) with one leader, a decentralized controller is proposed that yields exponential stability of the formation. Simulations validate the theoretical results.