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The mechanical properties between wheel and ground will affect the motion performance of wheeled omnidirectional mobile robot (OMR). MY3 wheel is an omnidirectional wheel. This paper aims to analyze the contact mechanical characteristics between MY3 wheel and ground to improve the motion accuracy of an omnidirectional mobile platform with MY3 wheel (MY3-OMR).

This method takes MY3 wheel as the research objective. The normal and tangential contact mechanics model and rolling contact mechanics model of MY3 wheel are established by analyzing the structure of MY3 wheel, and thereby, the slip ratio of MY3 wheel in the process of motion is calculated. The kinematics model of MY3-OMR is optimized by taking the slip ratio as the optimization parameter that aims to improve motion accuracy of MY3-OMR.

The correctness of the mechanical analysis and the feasibility of the method are verified by the MY3-OMR prototype. Let MY3-OMR move along the set circular trajectory and square trajectory, and the error between the motion trajectory before and after optimization and the standard trajectory is obtained. It illustrates that the error in the square trajectory is reduced by 1.5%, and the circular trajectory error is reduced by 2%; therefore, the method is effective.

A method based on contact mechanics is proposed and verified. Through the establishment of wheel-ground contact mechanics model to optimize MY3-OMR kinematics model, and thereby, the motion accuracy of MY3-OMR is improved, which lays a foundation for MY3-OMR engineering application.

This paper aims to propose a one-layer Mamdani hierarchical fuzzy system (HFS) to navigate autonomously an omnidirectional mobile robot to a target with a desired angle in unstructured environment. To avoid collision with unknown obstacles, Mamdani limpid hierarchical fuzzy systems (LHFS) are developed based on infrared sensors information and providing the appropriate linear speed controls.

The one-layer Mamdani HFS scheme consists of three fuzzy logic units corresponding to each degree of freedom of the holonomic mobile robot. This structure makes it possible to navigate with an optimized number of rules. Mamdani LHFS for obstacle avoidance consists of a number of fuzzy logic units of low dimension connected in a hierarchical structure. Hence, Mamdani LHFS has the advantage of optimizing the number of fuzzy rules compared to a standard fuzzy controller. Based on sensors information inputs of the Mamdani LHFS, appropriate linear speed controls are generated to avoid collision with static obstacles.

Simulation results are performed with MATLAB software in interaction with the environment test tool “Robotino Sim.” Experiments have been done on an omnidirectional mobile robot “Robotino.” Simulation results show that the proposed approaches lead to satisfied performances in navigation between static obstacles to reach the target with a desired angle and have the advantage that the total number of fuzzy rules is greatly reduced. Experimental results prove the efficiency and the validity of the proposed approaches for the navigation problem and obstacle avoidance collisions.

By comparing simulation results of the proposed Mamdani HFS to another navigational controller, it was found that it provides better results in terms of path length in the same environment. Moreover, it has the advantage that the number of fuzzy rules is greatly reduced compared to a standard Mamdani fuzzy controller. The use of Mamdani LHFS in obstacle avoidance greatly reduces the number of involved fuzzy rules and overcomes the complexity of high dimensionality of the infrared sensors data information.

The purpose of this paper is to achieve optimal climbing control of the gas-insulated switchgear (GIS) robot, as the authors know that the GIS inspection robot is a kind of artificial intelligent mobile equipment which auxiliary or even substitute human labor drive on the inner wall of the gas-insulated metal enclosed switchgear. The GIS equipment fault inspection and maintenance can be realized through the robot manipulator on the mobile platform and the camera carried on the fuselage, and it is a kind of intelligent equipment for operation. To realize the inspection and operation of the GIS equipment pipeline without blind spots, the robot is required to be able to travel on any wall inside the pipeline, especially the top of the pipeline and both right and left sides of the pipeline, which requires the flexible climbing of the GIS inspection robot. The robot device has a certain adsorption function to ensure that the robot is fully attached to the wall surface. At the same time, the robot manipulator can be used for collision-free obstacle avoidance operation planning in the narrow operation space inside the GIS equipment.

The above two technologies are the key that the robot completes the GIS equipment inspections. Based on this, this paper focuses on modeling and analysis of the chassis adsorption characteristics for the GIS inspection robot. At the same time, the Denavit Hartenberg (D-H) coordinate model of the robot arm system has been established, and the kinematics forward and inverse solutions of the robot manipulator system have been derived.

The reachable working space point cloud diagram of the robot manipulator in MATLAB has been obtained based on the kinematics analysis, and the operation trajectory planning of the robot manipulator using the robot toolbox has been obtained. The simulation results show that the robot manipulator system can realize the movement without collision and obstacle avoidance. The space can cover the entire GIS pipeline so as to achieve no blind area operation.

Finally, the GIS inspection robot physical prototype system has been developed through system integration design, and the inspection, maintenance operation experiment has been carried out in the actual GIS equipment. The entire robot system can complete the GIS equipment inspection operation soundly and improve the operation efficiency. The research in this paper has important theoretical significance and practical application value for the optimization design and practical research of the GIS inspection robot system.

Building inspection tasks usually involve working at life‐threatening height, especially for high‐rise buildings. The purpose of this paper is to introduce two service robots which are designed for high‐rise building inspection applications.

The first service robot, equipped with independent‐climbing capability, is applied to gas pipe inspection. The robot requires very little setup time and is suitable for some small inspection tasks. The second, which shares some similarities of industrial gondolas, is applied to check the health conditions of tile‐walls of high‐rise buildings. This robot requires more initial setup time but can provide faster inspection operations. In addition, it can be programmed to carry out the inspection task automatically. So, it is more suitable for large‐scale inspection tasks.

For tile‐wall inspection, a fast, low‐cost and effective non‐destructive testing technique based on impact acoustic method has been developed for the robot.

Both prototypes have been applied to housing estates for evaluation purposes.

This paper aims to propose a suitable motion control method for omni‐directional mobile robots (OMRs). In RoboCup competition, the robot moves in a dynamic and oppositional environment, which occurs with high acceleration and deceleration motion frequently, especially for our OMR that slipping is almost inherently encountered in motion. Therefore, the purpose of this paper is to present one improved dynamical model with slip, and then to propose one suitable path‐tracking controller based on it, which gives more accurate control result.

A dynamic modeling method for OMRs based on the theory of vehicle dynamics is proposed. By analyzing the wheel contact friction forces both in the wheel hub rolling direction and in the roller rolling direction, an amendatory dynamics model is presented. This model is introduced into the computed‐torque‐like‐controller (CTLC) system to solve the path‐tracking problem.

An amendatory dynamics model with slip is analyzed and introduced into the CTLC system to solve the path tracking problem for OMR in this paper. The anti‐disturbance ability and the trajectory tracking effect of the proposed motion control method are proven through simulations and experiments.

The proposed path tracking control method based on one improved dynamic model with slip is applied successfully to achieve effective motion control for one four‐wheel OMR, which is suitable for any kind of OMR.

One amendatory dynamics model including slipping between the wheels and ground is presented. Based on the above‐slipping model, one CTLC is implemented to solve the path‐tracking problem for one four‐wheel OMR.

Omnidirectional mobile platforms are still plagued by the problem of heading deviation. In four-Mecanum-wheel systems, this problem arises from the phenomena of dynamic imbalance and slip of the Mecanum wheels while driving. The purpose of this paper is to analyze the mechanism of omnidirectional motion using Mecanum wheels, with the aim of enhancing the heading precision. A proportional-integral-derivative (PID) setting control algorithm based on a radial basis function (RBF) neural network model is introduced.

In this study, the mechanism of omnidirectional motion using Mecanum wheels is analyzed, with the aim of enhancing the heading precision. A PID setting control algorithm based on an RBF neural network model is introduced. The algorithm is based on a kinematics model for an omnidirectional mobile platform and corrects the driving heading in real time. In this algorithm, the neural network RBF NN2 is used for identifying the state of the system, calculating the Jacobian information of the system and transmitting information to the neural network RBF NN1.

The network RBF NN1 calculates the deviations ?Kp, ?Ki and ?Kd to regulate the three coefficients Kp, Ki and Kd of the heading angle PID controller. This corrects the driving heading in real time, resolving the problems of low heading precision and unstable driving. The experimental data indicate that, for a externally imposed deviation in the heading angle of between 34º and ∼38°, the correction time for an omnidirectional mobile platform applying the algorithm during longitudinal driving is reduced by 1.4 s compared with the traditional PID control algorithm, while the overshoot angle is reduced by 7.4°; for lateral driving, the correction time is reduced by 1.4 s and the overshoot angle is reduced by 4.2°.

In this study, the mechanism of omnidirectional motion using Mecanum wheels is analyzed, with the aim of enhancing the heading precision. A PID setting control algorithm based on an RBF neural network model is introduced. The algorithm is based on a kinematics model for an omnidirectional mobile platform and corrects the driving heading in real time. In this algorithm, the neural network RBF NN2 is used for identifying the state of the system, calculating the Jacobian information of the system and transmitting information to the neural network RBF NN1. The method is innovative.

With the development of automation technology, the accuracy, bearing capacity and self-adaptation requirements of wheeled mobile robots are more and more demanding under various complex conditions, which will urge designers such shortcomings as the low accuracy, poor flexibility and weak obstacle crossing ability of traditional heavy haul vehicles and improve the wear resistance and bearing capacity of traditional omnidirectional wheels.

The optimal configuration for heavy payload transportation is obtained by building sliding friction consumption model of traditional wheels with different driving types based on Hertz tangential contact theory. The heavy payload omnidirectional wheel with a double-wheel steering and a coupled differential wheel driving is designed with the optimal configuration. The wheel consists of a differential gear train unit and a nonindependent suspension unit. Kinematics model of the wheel is established and relative parameters are optimized.

The prototype experiments show that the wheel has higher motion accuracy and environment adaptability. The results are consistent with the theoretical calculation, which show that the accuracy is more than 50% higher than that of differential prototype. The motion stability and the accuracy of the coupled differential omnidirectional wheel are better than those of the traditional omnidirectional wheels during the moving and obstacle crossing process under complex conditions, which verifies the correctness and advantages of the design.

Aiming at the specific application of heavy payload omnidirectional transportation, a new omnidirectional mobile mechanism with a two-wheel coupling drive structure and an adaptive mechanism is proposed. The simulation and experimental results show that it can realize the high-precision heavy-load omnidirectional movement, the effective contact with the ground and improve the adaptability to the rugged ground. It is flexible, simple and modular and can be widely applied to transportation, exploration, detection and other related industrial fields.

The purpose of this paper is to analyze the stability behavior of the omnidirectional mobile robot with active dual-wheel caster (ADWC) assemblies and provide a stable trajectory without any tip-over incident. The omnidirectional mobile robot to be developed is for transporting cuboid-shaped objects.

The omnidirectional transport mobile robot is designed using an ADWC assemblies structure, the tip-over occurrence is estimated based on the support forces of an active footprint, the tip-over direction is predicted, the tip-over stability is enhanced to prevent the tip-over occurrence and a fast traveling motion is provided.

The omnidirectional mobile robot tends to tip-over more on the sides with small ranges of tip-over angle. The proposed method for estimating the tip-over occurrence and enhancing the stability using the gyroscopic torque device was feasible as the tip-over prevention system of the omnidirectional mobile robot with ADWC assemblies.

The research addresses the study of the tip-over stability for the omnidirectional mobile robot that possesses an active footprint. It also addresses the prediction of the tip-over occurrence using the derived dynamical model together with force-angle stability measure and the tip-over stability enhancement method using a single-gimbal control moment gyro device.

The flexible automatic transportation and manual assembly jobs for large aircraft components demand an automated guided vehicle (AGV) system with heavy-duty capacity and omnidirectional movability. This paper aims to propose a four driving-steering wheels-four supporting-steering wheels (4DSW-4SSW) layout plan to enhance the controllability and moving stability of AGV.

The anti-vibration structure of DS wheels and high-torque steering mechanism of SS wheels with tapered rolling bearings are rigorously designed to meet the functional requirements. Based on the specific wheel layout and vehicle dynamics, the rotational kinematic model as well as the straight and rotational dynamic models of AGV are established by the authors. To well verify the motion characteristics of wheels under heavy load in three motion states including straight motion, self-rotation and rotation around a certain point, the simulations in ADAMS and factory experiments have all been conducted.

Simulation results indicate that normal and friction forces of DS wheels and SS wheels are very stable except for some small oscillations, which are caused by non-center load distribution on AGV. Experimental results on driving speed of AGV have directly demonstrated that its positioning accuracy is enough for use in real aircraft assembly lines.

The designed AGV system has been applied to the final assembly line of a certain aircraft in Aviation Industry Corporation of China, Ltd, whose assembly efficiency and flexibility have been significantly improved.

A new layout plan of wheels for an omnidirectional heavy-duty AGV is proposed, which enhances the operating and moving capacity of AGV. A function of human-machine collaboration is also offered by the AGV for transporting large workpieces intelligently and economically in aerospace and other heavy industries.

The purpose of this paper is to propose an enhanced pose tracking method using progressive scan matching, focusing on accuracy, time efficiency and robustness.

The general purpose of localization algorithms is to dynamically track a robot instead of globally locating one. In this paper, progressive scan matching is used to promote the performance of pose tracking. Rotational and translational samples are separately generated to accelerate the calculation and to increase the accuracy. Progressive iteration of sample generation can ensure localization to achieve a specific precision. The direction of localization uncertainty is taken into consideration to increase robustness. Nonlinear optimization is adopted to achieve a more precise result.

The proposed method was implemented on a self-made mobile robot. Two experiments were conducted to test the accuracy and time efficiency of the method. The comparison with the basic Monte Carlo localization shows the advantages of the method. Another two experiments were conducted to test the robustness of the method. The result shows that the method can relocate a robot from an inaccurate place if the offset is moderate.

An enhanced pose tracking method is proposed to promote the performance by separately processing rotational and translational samples, progressively iterating the sample generation, taking the direction of localization uncertainty into consideration and adopting nonlinear optimization. The proposed method enables a robot to accurately and quickly locate itself in the environment with robustness.