Omnidirectional Wheeled Robot Research Articles

Practical Obstacle-Overcoming Robot with a Heterogeneous Sensing System: Design and Experiments

It is challenging for robots to improve their ability to pass through unstructured environments while maximizing motion performance in cities and factories. This paper presents an omnidirectional deformable wheeled robot based on a heterogeneous sensing system. We presented a novel structure with dual swing arms and six wheels. Moreover, the heterogeneous sensing system can perceive critical environmental data, such as friction and temperature, to assist the robot in executing different functions. In addition, a top-down ‘Order–Decision–Behaviour’ overall motion strategy is proposed based on the data acquisition. The strategy combines the key condition parameters with a kinetic model to integrate the robot’s movement, overcoming of obstacles, and mode switching. The robot is flexible and fast in moving mode and can overcome obstacles safely, reliably, and simply. This study describes the robot’s design, strategy, simulation, and experiments. Motion performance and strategy were investigated and evaluated in field environments.

Overcoming Kinematic Singularities for Motion Control in a Caster Wheeled Omnidirectional Robot

Omnidirectional planar robots are common these days due to their high mobility, for example in human–robot interactions. The motion of such mechanisms is based on specially designed wheels, which may vary when different terrains are considered. The usage of actuated caster wheels (ACW) may enable the usage of regular wheels. Yet, it is known that an ACW robot with three actuated wheels needs to overcome kinematic singularities. This paper introduces the kinematic model for an ACW omni robot. We present a novel method to overcome the kinematic singularities of the mechanism’s Jacobian matrix by performing the time propagation in the mechanism’s configuration space. We show how the implementation of this method enables the estimation of caster wheels’ swivel angles by tracking the plate’s velocity. We present the mechanism’s kinematics and trajectory tracking in real-world experimentation using a novel robot design.

Structure design of an omni-directional wheeled handling robot

In response to the demand for automated item handling, this paper proposes an omnidirectional wheeled handling robot. Firstly, determine that its mobile platform is based on the design of the Mecanum wheel, which can move safely and efficiently. Secondly, according to the common object shapes, a single-side opening and closing insertion rack clamping mechanism is proposed. Thirdly, in order to meet the needs of transporting objects and avoid interference with the movement of the moving body, the mechanical arm is a four-degree-of-freedom joint structure. Finally, a decelerated AC servo motor with self-locking function is selected as the drive motor, and a low-speed motor with a reducer is used as the drive element of the moving body.

Robust Observer-based Control of Nonlinear Multi-Omnidirectional Wheeled Robot Systems via High Order Sliding-mode Consensus Protocol

This paper presents a novel observer-based controller for a class of nonlinear multi-agent robot models using the high order sliding mode consensus protocol. In many applications, demand for autonomous vehicles is growing; omnidirectional wheeled robots are suggested to meet this demand. They are flexible, fast, and autonomous, able to find the best direction and can move on an optional path at any time. Multi-agent omnidirectional wheeled robot (MOWR) systems consist of several similar or different robots and there are multiple different interactions between their agents, thus the MOWR systems have complex dynamics. Hence, designing a robust reliable controller for the nonlinear MOWR operations is considered an important obstacles in the science of the control design. A high order sliding mode is selected in this work that is a suitable technique for implementing a robust controller for nonlinear complex dynamics models. Furthermore, the proposed method ensures all signals involved in the multi-agent system (MAS) are uniformly ultimately bounded and the system is robust against the external disturbances and uncertainties. Theoretical analysis of candidate Lyapunov functions has been presented to depict the stability of the overall MAS, the convergence of observer and tracking error to zero, and the reduction of the chattering phenomena. In order to illustrate the promising performance of the methodology, the observer is applied to two nonlinear dynamic omnidirectional wheeled robots. The results display the meritorious performance of the scheme.

Implementation Kinematics Modeling and Odometry of Four Omni Wheel Mobile Robot on The Trajectory Planning and Motion Control Based Microcontroller

The control of kinematic modeling in a four wheel omni-directional robot (FWOR) is very difficult. Because you have to adjust the speed of the four DC motors. The speed of DC motors is controlled so that the FWOR robot can be controlled. This paper will explain the application of kinematic modeling of four wheel omni directional robots as track tracking controllers and microcontroller based movement control. Kinematic is the study of robot motion based on geometric structure analysis of a stationary / moving reference coordinate frame system without considering the force, torque or certain moments that cause movement. By applying kinematic modeling and calculation of the odometric system as feedback, the control of the robot trajectory movement can be controlled with precision in accordance with the path planning that has been made. The robot track control technique is embedded in a 32-bit ARM microcontroller. The path planning system and observing robot movement are carried out using a friendly graphic interface using Processing to facilitate the robot monitoring process. The results of the experiments and tests carried out, the system is able to control the rate of movement of the robot with great precision in accordance with the path planning made.

Experimental Analysis the Forward and Reverse Motion of Three Omnidirectional Wheel Robot (TODWR)

Presently in the automation era vehicle robot is very important, therefore analysis the vehicle robot is most interesting topic for researchers. Omnidirectional wheels brought a renaissance in the area of vehicle robot. This study presents a design of the three omnidirectional wheeled robot (TODWR) controller and its application for a vehicle robot. As the omnidirectional wheels’ has a holonomic character, the three omnidirectional wheeled robot (TODWR) are capable to move any desire trajectory. The chassis of this robot is equilateral triangle shape and all omnidirectional wheels are arranged each of the corners of the triangle. The track are designed on the fixed world frame and then converted by the method of inverse kinematic to individual motor speeds.

Trajectory Path Analysis of Three Omnidirectional Wheel Robot (TODWR)

Presently there is a demand for vehicle robot in automated industry, military and hospital areas etc. Three omnidirectional wheel robot (TODWR) is basically a holonomic mobile vehicle which can achieve rotational and translational motions simultaneously and autonomously. This study exhibits the analysis of kinematics and dynamic motion of the three omnidirectional wheeled robot (TODWR). The TODWR robot is prepared by three wheels which are omnidirectional and set at the corners of triangle geometry shape chassis which is basically equilateral. This TODWR robot was performed by experimentally with different combination of wheel’s movement and it is also noted, different trajectory motion of TODWR robot.

Sensor-based Navigation of Omnidirectional Wheeled Robots Dealing with both Collisions and Occlusions

SUMMARYNavigation tasks are often subject to several constraints that can be related to the sensors (visibility) or come from the environment (obstacles). In this paper, we propose a framework for autonomous omnidirectional wheeled robots that takes into account both collision and occlusion risk, during sensor-based navigation. The task consists in driving the robot towards a visual target in the presence of static and moving obstacles. The target is acquired by fixed – limited field of view – on-board cameras, while the surrounding obstacles are detected by lidar scanners. To perform the task, the robot has not only to keep the target in view while avoiding the obstacles, but also to predict its location in the case of occlusion. The effectiveness of our approach is validated through several experiments.

Damping and Transfer Control System With Parallel Linkage Mechanism-Based Active Vibration Reducer for Omnidirectional Wheeled Robots

This paper proposes a damping and transfer control system with an active vibration reducer for omnidirectional wheeled robots. The active vibration reducer, which is installed on omnidirectional wheeled robots that use three omni wheels, employs a parallel linkage mechanism and three pneumatic actuators. A spherical pendulum, used as a tentative transfer object, is installed on the endplate of the reducer. The acceleration of the robot is shaped with a notch-filter, and the endplate is controlled by an optimal regulator to damp the swinging of the pendulum generated as the robot moves. The results of experiments conducted in which the robot travelled horizontally along a smooth straight path and a smooth circular path, respectively, and also along a straight path over uneven terrain indicate that the damping performance of the proposed system is effective and satisfactory.

Online Policy Iteration-Based Tracking Control of Four Wheeled Omni-Directional Robots

In this paper, online policy iteration reinforcement learning (RL) algorithm is proposed for motion control of four wheeled omni-directional robots. The algorithm solves the linear quadratic tracking (LQT) problem in an online manner using real-time measurement data of the robot. This property enables the tracking controller to compensate the alterations of dynamics of the robot's model and environment. The online policy iteration based tracking method is employed as low level controller. On the other side, a proportional derivative (PD) scheme is performed as supervisory planning system (high level controller). In this study, the followed paths of online and offline policy iteration algorithms are compared in a rectangular trajectory in the presence of slippage drawback and motor heat. Simulation and implementation results of the methods demonstrate the effectiveness of the online algorithm compared to offline one in reducing the command trajectory tracking error and robot's path deviations. Besides, the proposed online controller shows a considerable ability in learning appropriate control policy on different types of surfaces. The novelty of this paper is proposition of a simple-structure learning based adaptive optimal scheme that tracks the desired path, optimizes the energy consumption, and solves the uncertainty problem in omni-directional wheeled robots.

Trajectory Tracking of an Omni-Directional Wheeled Mobile Robot Using a Model Predictive Control Strategy

This paper addresses trajectory tracking of an omni-directional mobile robot (OMR) with three mecanum wheels and a fully symmetrical configuration. The omni-directional wheeled robot outperforms the non-holonomic wheeled robot due to its ability to rotate and translate independently and simultaneously. A kinematics model of the OMR is established and a model predictive control (MPC) algorithm with control and system constraints is designed to achieve point stabilization and trajectory tracking. Simulation results validate the accuracy of the established kinematics model and the effectiveness of the proposed MPC controller.

Parametric Uncertainties Prone Adaptive Control Method for Omni Directional Vehicle

The trajectory tracking problem of a wheeled omnidirectional robot is addressed in this paper. The proposed controller takes into account the dynamics of the wheeled omnidirectional robot when adaptive linear control with computed torque is utilized for tracking its trajectory. The computed torque method was employed to follow a reference trajectory but there were certain degrees of uncertainties in parameters such as estimation of mass and inertia which caused the performance to deviate from the ideal case. The adaptive linear control method is used to overcome the degradation of the computed torque when there is drift in vehicle parameters. Lyapunov stability criteria was utilized to prove that the proposed adaptive linear control with computed torque method is stable. The proposed strategy was evaluated through numerical simulation which showed the better performance in tracking a reference signal of the adaptive linear control with computed torque method as compared to computed torque method only.

Kinematics modeling and simulation of an autonomous omni-directional mobile robot

<p class="Abstractandkeywordscontent"><span lang="EN-US">Although robotics has progressed to the extent that it has become relatively accessible with low-cost projects, there is still a need to create models that accurately represent the physical behavior of a robot. Creating a completely virtual platform allows us to test behavior algorithms such as those implemented using artificial intelligence, and additionally, it enables us to find potential problems in the physical design of the robot. The present work describes a methodology for the construction of a kinematic model and a simulation of the autonomous robot, specifically of an omni-directional wheeled robot. This paper presents the kinematic model development and its implementation using several tools. The result is a model that follows the kinematics of a triangular omni-directional mobile wheeled robot, which is then tested by using a 3D model imported from 3D Studio</span><span lang="EN-US">®</span><span lang="EN-US"> and Matlab</span><span lang="EN-US">® for the simulation. The environment used for the experiment is very close to the real environment and reflects the kinematic characteristics of the robot.</span></p>

Design and Movement Analysis of Single Roller Omni Directional Wheeled Robot for Different Assembly Structures

This paper addresses the movement analysis of square structured and triangular structured Omni directional mobile robots and its combination in the form of octagonal structured mobile robot. The Omni wheel used in this research is having 8 rollers made up of synthetic rubber coated polypropylene rollers. An experiment was setup to analyse the movement of the square, triangular and octagonal structured robot in x-axis, y-axis and rotary motion. This experiment is an attempt of combining square structure and triangular structure robot in a single robot. Omni Directional mobile robot creates another step in the field of mobile robotics.

Model Reference Switching Quasi-LPV Control of a Four Wheeled Omnidirectional Robot

In this paper, the problem of trajectory tracking for a four wheeled omnidirectional robot is solved in the inertial fixed coordinate system. The solution relies on a reference model approach, where the resulting nonlinear error model is brought to a quasi-Linear Parameter Varying (LPV) form suitable for designing an LPV controller using Linear Matrix Inequalities (LMI)-based techniques. In particular, the controller is obtained within the switching LPV framework. The effectiveness of the proposed approach is shown through simulation results.

Analysis of Climbing Obstacle Capability and its Influential Factors of Omni-Directional Wheeled Robot

The perpendicular climbing obstacle capability of omni-directional wheeled robot was studied, based on simplified mechanics model. The relation between influential factors and perpendicular climbing obstacle height was given under two conditions: simultaneously climbing obstacle by two front wheels and simultaneously climbing obstacle by two rear wheels. Then maximum perpendicular climbing obstacle height of this omni-directional wheeled robot was calculated. Simulation analysis to the result by MATLAB was done. The simulation analysis gave theoretical foundation to the climbing obstacle capability of omni-directional wheeled robot.

Trajectory Tracking Control of Omni-directional Wheeled Robot for Lower Limbs Rehabilitative Training

Omni-directional wheeled robot for lower limbs rehabilitative training needs to track trajectory which is set by doctors.The uncertainties of the robot and the disturbances caused by trained patient affect the tracking performances. A nonlinear robust L_2 controller is presented to solve disturbance rejection problems.Kinematics model of lower limbs rehabilitative training robot is presented,thereby,a kinematics model of the position error system is established.The tracking and uncertain disturbance rejection are formulated as an L_2 control question to design control law with backstepping algorithm in a built storage function.A trajectory tracking controller meeting the disturbance rejection requirement is constructed. Simulation and experiment results show that the proposed controller is effective.

Trajectory Tracking of Omni-Directional Wheeled Opera Robot Based on Wavelet

As the perfect fusion of intelligent robotics and China's classic culture, Opera robots, two omni-directional wheeled robots were made in my research centre. They can smoothly fight with each other just as Opera actors. A novel trajectory tracking method based on robotic dynamics model and wavelet sampling theorem for Opera robot is proposed in this paper. The formula for calculating torque of each driving motor when the robot moves along spline curves is studied in detail. By experiment, the robot can be derived smoothly to track predetermined trajectory.

Bio-inspired algorithm for wheeled robot's navigation

This paper discusses the bio-inspired algorithm of the Particle Swarm Optimisation (PSO) for a wheeled robot|s displacement. PSO was selected because its flexibility and its tempting results. An omnidirectional wheeled robot was simulated on a flat environment with two tasks: |Reach a goal| or |collect balls|. This paper checks on the performance of PSO for the displacement studied. In the first case, we discussed the variation of execution time compared to the particles| and the neighbours| number. In the second one, we studied the change in the path|s length compared to execution time depending on the particles| and balls| number.

Intelligent Adaptive Motion Controller Design for Mecanum Wheeled Omnidirectional Robots with Parameter Variations

Intelligent Adaptive Motion Controller Design for Mecanum Wheeled Omnidirectional Robots with Parameter Variations