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The focus of this survey is the modeling and control of a 6 DOF arm robot. Based on Lagrangian dynamics, a 6 DOF(degree of freedom) arm robot model is built. The computed torque control (CTC) is applied to the position tracking control and a planned trajectory is given. Furthermore, to improve the tracking speed and achieve the velocity tracking, a nonlinear integral backstepping (NIB) technique is...
Although pneumatic actuators have a good power-weight ratio, there is a reduced number of works that consider them to be applied in manipulator robots, mainly because they present difficulties to be controlled, and nonlinearities that make them complicated to obtain a mathematical model which describes their behavior in specific conditions. Control techniques can be implemented in this kind of actuators,...
The rapid development of aerospace technology means that the roles of space robots are becoming important. In order to reduce fuel consumption and successfully accomplish on-orbit service tasks, the base attitude disturbance should be as small as possible. When the particle swarm optimization (PSO) algorithm based trajectory planning method is applied to solve the problem, it is falling into local...
Exact estimation of link length and joint position of human body is an important application in biomechanics, motion synthesis and analysis. Since human joint angles are not measureable, the starting point in studying this application is dealing with the identification of a robot based on task space measurement. The purpose of this study is to present a method to estimate robot joint parameters without...
This work proposes a framework that enables arbitrary robots with unknown kinematics models to imitate human demonstrations to acquire a skill, and reproduce it in real-time. The diversity of robots active in non-laboratory environments is growing constantly, and to this end we present an approach for users to be able to easily teach a skill to a robot with any body configuration. Our proposed method...
One of the challenging issues in the robotic technology is to use robotics arm for surgeries, especially in eye operations. Among the recently developed mechanisms for this purpose, there exists a robot, called Eye-RHAS, that presents sustainable precision in vitreo-retinal eye surgeries. In this work the closed-form dynamical model of this robot has been derived by Gibbs-Appell method. Furthermore,...
In this paper, we propose a relatively simple approach to solve the motion control problem of a three dimensional articulated manipulator arm. The manipulator arm has two links connected by a revolute joint and is anchored on a rotatable base. The kinematic model is developed and a velocity based algorithm is used to move the end-effector from an initial position to a goal position taking into account...
In this paper, an optimal trajectory of the variable geometry truss (VGT) manipulator in point-to-point motion is proposed. To achieve this goal, the kinematic model of a VGT module is introduced and a trajectory optimization model considering the physical limits of the VGT manipulator is accomplished. By employing LMI (Linear Matrix Inequalities) optimization, the problem gets solved under some restraint...
This paper presents a fuzzy logic control approach for trajectory tracking of Stewart platform which is a six degrees of freedom parallel manipulator. In order to have a robust tracking a fuzzy logic controller, convenient for nonlinear complex systems, is developed. The performance of the developed FLC is compared with classical PID controller. The performances of both controllers are measured using...
Survey of literature has revealed research on excavators in trajectory analysis, modeling, control, soil-tool interaction, energy efficiency, and simulators. Kinematics of excavators has largely remained unchanged over time. Dynamic models of 3 degree of freedom (DOF) manipulator have been applied in literature. Soil-tool interaction models are becoming computationally less demanding and more accurate,...
Orbital robotics, due to the unfriendly environment (radiation, micro-gravity, thermal stresses, etc.) poses unique challenges to robot and robot algorithms, and sets the need for new and innovative autonomous systems. The design of servicing operations and devices is nowadays one of the most important research field in space robotics. Servicing operations range from regular inspection to the upgrade...
A grinding robot is composed of six joints, within which the second joint is a prismatic joint and the others are rotational joints. According to its configuration characteristic, the 6DOF of the inverse kinematics problem was decomposed into two 3DOF sub-problems: the position inverse kinematics and the attitude inverse kinematics. Then the two sub-problems were respectively solved analytically,...
This paper addresses a sliding mode control scheme based on weighted integral gain reaching for a novel 3-DOF redundantly actuated parallel mechanism to implement accuracy motion tracking control. The sliding control scheme is designed with consideration of varying uncertain parameters and external disturbances to guarantee system robustness. Using Lyapunov stability theory, the closed-loop system...
In this paper, a 2-DOF robotic manipulator is controlled to track the motion of object in a plane using brushless DC motor as an actuator. Two brushless DC motor are used to actuate the each of two revolute joints of the 2-DOF robotic manipulator. To control the angular position of robotic arm fuzzy PD controller is used. To generate the Smooth trajectory for joint angle of robotic manipulator, cubic...
Parallel-architecture haptic devices offer significant advantages over serial-architecture counterparts in applications requiring high stiffness and high accuracy. To this end, many haptic devices have been created and deployed by modularly piecing together several serial-chain arms to form an in-parallel system. However, the overall system performance depends both on the nature of the individual...
Compared with serial robots, because of some advantages, e.g. higher stiffness, errors will not accumulated, parallel robot has much potential use. To 3-RPS parallel robot, there are 3 controllable degrees of freedom (axis x, axis y, axis z, or angle x, angle y, axis z). It may be called position kinematics or posture kinematics. According to structural characteristics of the 3-RPS parallel robot,...
Cable-driven robots are currently extensively studied. Generally, for this type of manipulators, cables are considered to be massless and inextensible. But for large working volume applications, their mass cannot be neglected. Based on a well-known model which describes the profile of a cable under the action of its own weight, the inverse and forward kinematics of minimally constrained cable-driven...
Based on the SimMechanics Toolbox of MATLAB, this paper introduces a method of simulation in researching 3-RRRT parallel manipulator. Through deeply studying fuzzy control theory, for overcoming the shortcomings and inadequacies of the PID control algorithm, a fuzzy adaptive supervisory algorithm is presented in this paper. The paper discusses how to use it to optimize the conventional PID controller,...
This paper presents the ground work prepared for turning a bucket wheel reclaimer (BWR) into a robotic arm for operation automation. BWR has been widely used in dealing with bulk materials by removing them from the conveyor and stack them as well as to load stacked materials onto the in-feed conveyor, such as in mining industry. Generally speaking, current BWRs are manually operated, remotely operated,...
A novel model-based controller for six degree of freedom (dof) parallel manipulator-PID controller with gravity compensation is developed, in order to improve the control precision of six-dof hydraulic driven parallel manipulator with long stroke hydraulic actuator and heavy load. In this paper, six-dof parallel manipulator is described as a thirteen rigid-body systems. The mathematical model of gravity...
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