scholarly journals End-Effector Position Analysis Using Forward Kinematics For 5 Dof Pravak Robot Arm

2013 ◽  
Vol 2 (3) ◽  
Author(s):  
Jolly Atit Shah ◽  
S.S. Rattan ◽  
B.C. Nakra
Keyword(s):  
Forward Kinematics ◽  
Robot Arm ◽  
End Effector ◽  
Position Analysis

Design and Analysis of a Biomimetic Wire-Driven Robot Arm

2011 ◽  
Author(s):  
Zheng Li ◽  
Ruxu Du ◽  
Man Cheong Lei ◽  
Song Mei Yuan
Keyword(s):  
Inverse Kinematics ◽  
Geometric Analysis ◽  
Forward Kinematics ◽  
Positioning Error ◽  
Robot Arm ◽  
End Effector ◽  
Fixed Node

Inspired by the octopus and snakes, we designed and built a wire-driven serpentine robot arm. The robot arm is made of a number of rigid nodes connected by two sets of wires. The rigid nodes act as the backbone while the wires work as the muscle, which enables the 2 DOF bending. The forward kinematics is derived using D-H method, while the inverse kinematics and its workspace can be solved by geometric analysis. To validate the design, a prototype is built. It is found that the positioning error of the robot arm is generally less than 2%. The advantage of this robot arm is that with several nodes fixed the rest nodes are still controllable. The positioning error is smaller when the fixed node is closer to the end effector.

Three-Degree-of-Freedom Parallel Robot Arm

2006 ◽  
Author(s):  
Martin Hosek ◽  
Michael Valasek ◽  
Jairo Moura
Keyword(s):  
Parallel Robot ◽  
Degree Of Freedom ◽  
Motion Path ◽  
Angular Orientation ◽  
Robot Arm ◽  
Flat Panel Display ◽  
End Effector ◽  
Cluster Tools ◽  
Manufacturing Applications ◽  
Three Degree Of Freedom

This paper presents single- and dual-end-effector configurations of a planar three-degree of freedom parallel robot arm designed for automated pick-place operations in vacuum cluster tools for semiconductor and flat-panel-display manufacturing applications. The basic single end-effector configuration of the arm consists of a pivoting base platform, two elbow platforms and a wrist platform, which are connected through two symmetric pairs of parallelogram mechanisms. The wrist platform carries an end-effector, the position and angular orientation of which can be controlled independently by three motors located at the base of the robot. The joints and links of the mechanism are arranged in a unique geometric configuration which provides a sufficient range of motion for typical vacuum cluster tools. The geometric properties of the mechanism are further optimized for a given motion path of the robot. In addition to the basic symmetric single end-effector configuration, an asymmetric costeffective version of the mechanism is derived, and two dual-end-effector alternatives for improved throughput performance are described. In contrast to prior attempts to control angular orientation of the end-effector(s) of the conventional arms employed currently in vacuum cluster tools, all of the motors that drive the arm can be located at the stationary base of the robot with no need for joint actuators carried by the arm or complicated belt arrangements running through the arm. As a result, the motors do not contribute to the mass and inertia properties of the moving parts of the arm, no power and signal wires through the arm are necessary, the reliability and maintenance aspects of operation are improved, and the level of undesirable particle generation is reduced. This is particularly beneficial for high-throughput applications in vacuum and particlesensitive environments.

Cooperation and Null-Space Control of Networked Omni-Directional Mobile Manipulators

2020 ◽  
Author(s):  
Michael John Chua ◽  
Yen-Chen Liu
Keyword(s):  
Degrees Of Freedom ◽  
Null Space ◽  
Kinematic Model ◽  
Mobile Manipulator ◽  
Main Task ◽  
Mobile Manipulators ◽  
Robot Arm ◽  
Task Space ◽  
End Effector ◽  
Mobile Base

Abstract This paper presents cooperation and null-space control for networked mobile manipulators with high degrees of freedom (DOFs). First, kinematic model and Euler-Lagrange dynamic model of the mobile manipulator, which has an articulated robot arm mounted on a mobile base with omni-directional wheels, have been presented. Then, the dynamic decoupling has been considered so that the task-space and the null-space can be controlled separately to accomplish different missions. The motion of the end-effector is controlled in the task-space, and the force control is implemented to make sure the cooperation of the mobile manipulators, as well as the transportation tasks. Also, the null-space control for the manipulator has been combined into the decoupling control. For the mobile base, it is controlled in the null-space to track the velocity of the end-effector, avoid other agents, avoid the obstacles, and move in a defined range based on the length of the manipulator without affecting the main task. Numerical simulations have been addressed to demonstrate the proposed methods.

Design, Modelling and Simulation of a Rotational Robotic Arm

2020 ◽  
Author(s):  
Bin Wei
Keyword(s):  
Angular Velocity ◽  
3D Model ◽  
Modelling And Simulation ◽  
Robotic Arm ◽  
Forward Kinematics ◽  
Position Vector ◽  
Control Law ◽  
Model Design ◽  
End Effector ◽  
Design And Optimization

Abstract In this paper, a rotational robotic arm is designed, modelled and optimized. The 3D model design and optimization are conducted by using SolidWorks. Forward kinematics are derived so as to determine the position vector of the end effector with respect to the base, and subsequently being able to calculate the angular velocity and torque of each joint. For the goal positioning problem, the PD control law is typically used in industry. It is employed in this application by using virtual torsional springs and frictions to generate the torques and to keep the system stable.

scholarly journals A Novel Kinematically Redundant Planar Parallel Robot Manipulator With Full Rotatability

2018 ◽  
Vol 11 (1) ◽  
Author(s):  
Nicholas Baron ◽  
Andrew Philippides ◽  
Nicolas Rojas
Keyword(s):  
Potential Application ◽  
Robot Manipulator ◽  
Video Recording ◽  
Parallel Robot ◽  
Singularity Analysis ◽  
Geometric Method ◽  
Forward Kinematics ◽  
Online Video ◽  
End Effector ◽  
Moving Platform

This paper presents a novel kinematically redundant planar parallel robot manipulator, which has full rotatability. The proposed robot manipulator has an architecture that corresponds to a fundamental truss, meaning that it does not contain internal rigid structures when the actuators are locked. This also implies that its rigidity is not inherited from more general architectures or resulting from the combination of other fundamental structures. The introduced topology is a departure from the standard 3-RPR (or 3-RRR) mechanism on which most kinematically redundant planar parallel robot manipulators are based. The robot manipulator consists of a moving platform that is connected to the base via two RRR legs and connected to a ternary link, which is joined to the base by a passive revolute joint, via two other RRR legs. The resulting robot mechanism is kinematically redundant, being able to avoid the production of singularities and having unlimited rotational capability. The inverse and forward kinematics analyses of this novel robot manipulator are derived using distance-based techniques, and the singularity analysis is performed using a geometric method based on the properties of instantaneous centers of rotation. An example robot mechanism is analyzed numerically and physically tested; and a test trajectory where the end effector completes a full cycle rotation is reported. A link to an online video recording of such a capability, along with the avoidance of singularities and a potential application, is also provided.

scholarly journals Detachable Robotic Grippers for Human-Robot Collaboration

2021 ◽  
Vol 8 ◽  
Author(s):  
Zubair Iqbal ◽  
Maria Pozzi ◽  
Domenico Prattichizzo ◽  
Gionata Salvietti
Keyword(s):  
Degrees Of Freedom ◽  
Tactile Feedback ◽  
Industrial Robots ◽  
Physical Interaction ◽  
Robot Arm ◽  
Robotic Hands ◽  
End Effector ◽  
External Power ◽  
Self Powered ◽  
Automatic Tool

Collaborative robots promise to add flexibility to production cells thanks to the fact that they can work not only close to humans but also with humans. The possibility of a direct physical interaction between humans and robots allows to perform operations that were inconceivable with industrial robots. Collaborative soft grippers have been recently introduced to extend this possibility beyond the robot end-effector, making humans able to directly act on robotic hands. In this work, we propose to exploit collaborative grippers in a novel paradigm in which these devices can be easily attached and detached from the robot arm and used also independently from it. This is possible only with self-powered hands, that are still quite uncommon in the market. In the presented paradigm not only hands can be attached/detached to/from the robot end-effector as if they were simple tools, but they can also remain active and fully functional after detachment. This ensures all the advantages brought in by tool changers, that allow for quick and possibly automatic tool exchange at the robot end-effector, but also gives the possibility of using the hand capabilities and degrees of freedom without the need of an arm or of external power supplies. In this paper, the concept of detachable robotic grippers is introduced and demonstrated through two illustrative tasks conducted with a new tool changer designed for collaborative grippers. The novel tool changer embeds electromagnets that are used to add safety during attach/detach operations. The activation of the electromagnets is controlled through a wearable interface capable of providing tactile feedback. The usability of the system is confirmed by the evaluations of 12 users.

Finite element method stiffness analysis of a novel telemanipulator for minimally invasive surgery

SIMULATION ◽  
2019 ◽  
Vol 95 (11) ◽  
pp. 1015-1025 ◽  
Author(s):  
Roman Trochimczuk ◽  
Andrzej Łukaszewicz ◽  
Tadeusz Mikołajczyk ◽  
Francesco Aggogeri ◽  
Alberto Borboni
Keyword(s):  
Minimally Invasive Surgery ◽  
Minimally Invasive ◽  
Invasive Surgery ◽  
Numerical Study ◽  
Kinematic Chain ◽  
Robot Arm ◽  
End Effector ◽  
Stiffness Analysis ◽  
Position Accuracy ◽  
Main Factors

This paper presents the concept of a novel telemanipulator for minimally invasive surgery, along with numerical analysis to validate the main system performance. The proposed kinematic structure consists of a passive and an active module. The passive module is similar to the Selective Compliance Assembly Robot Arm - SCARA robot. The active module is based on a parallelogram mechanism. The results of the numerical study are discussed, focusing on the influence of geometry parameters of the kinematic chain on the displacement accuracy of the end-effector. In particular, the paper deals with the identification of the main factors that impact the position accuracy of the robot.

Analyses of Error and Precision of 6-DOF Platform

2012 ◽  
Vol 591-593 ◽  
pp. 2081-2086 ◽  
Author(s):  
Rui Ren ◽  
Chang Chun Ye ◽  
Guo Bin Fan
Keyword(s):  
Inverse Kinematics ◽  
Newton Iteration ◽  
Forward Kinematics ◽  
Parallel Mechanisms ◽  
End Effector ◽  
C Programming Language ◽  
C Programming ◽  
Manufacturing Tolerances ◽  
Parallel Robotics ◽  
Forward Kinematic

A particular subset of 6-DOF parallel mechanisms is known as Stewart platforms (or hexapod). Stewart platform characteristic analyzed in this paper is the effect of small errors within its elements (strut lengths, joint placement) which can be caused by manufacturing tolerances or setting up errors or other even unknown sources to end effector. The biggest kinematics problem is parallel robotics which is the forward kinematics. On the basis of forward kinematic of 6-DOF platform, the algorithm model was built by Newton iteration, several computer programs were written in the MATLAB and Visual C++ programming language. The model is effective and real-time approved by forwards kinematics, inverse kinematics iteration and practical experiment. Analyzing the resource of error, get some related spectra map, top plat position and posture error corresponding every error resource respectively. By researching and comparing the error spectra map, some general results is concluded.

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