scholarly journals Kinematics Analysis and Modeling of 6 Degree of Freedom Robotic Arm from DFROBOT on Labview

2016 ◽  
Vol 13 (7) ◽  
pp. 569-575 ◽  
Author(s):  
Hanan A.R. Akkar ◽  
Ahlam Najim A-Amir
Keyword(s):  
Degree Of Freedom ◽  
Robotic Arm ◽  
Kinematics Analysis

Parametric Design of a Spherical Eight-Bar Linkage Based on a Spherical Parallel Manipulator

2008 ◽  
Vol 1 (1) ◽  
Author(s):  
Gim Song Soh ◽  
J. Michael McCarthy
Keyword(s):  
Inverse Kinematics ◽  
Parallel Manipulator ◽  
Parametric Design ◽  
Degree Of Freedom ◽  
Kinematics Analysis ◽  
End Effector ◽  
Arbitrary Base ◽  
Three Degree Of Freedom ◽  
Spherical Parallel Manipulator

This paper presents a procedure that determines the dimensions of two constraining links to be added to a three degree-of-freedom spherical parallel manipulator so that it becomes a one degree-of-freedom spherical (8, 10) eight-bar linkage that guides its end-effector through five task poses. The dimensions of the spherical parallel manipulator are unconstrained, which provides the freedom to specify arbitrary base attachment points as well as the opportunity to shape the overall movement of the linkage. Inverse kinematics analysis of the spherical parallel manipulator provides a set of relative poses between all of the links, which are used to formulate the synthesis equations for spherical RR chains connecting any two of these links. The analysis of the resulting spherical eight-bar linkage verifies the movement of the system.

scholarly journals Adaptive robust control of quadrotor with a 2-degree-of-freedom robotic arm

2018 ◽  
Vol 10 (8) ◽  
pp. 168781401877863 ◽  
Author(s):  
Ran Jiao ◽  
Wusheng Chou ◽  
Rui Ding ◽  
Mingjie Dong
Keyword(s):  
Dynamic Models ◽  
Sliding Mode ◽  
Center Of Gravity ◽  
Adaptive Robust Control ◽  
Degree Of Freedom ◽  
Robotic Arm ◽  
Sliding Mode Controller ◽  
Adaptive Backstepping ◽  
Terminal Sliding Mode ◽  
Variable Center

The control of quadrotor equipped with a robotic arm has received growing challenges. This article proposes a new adaptive control strategy of quadrotor equipped with a 2-degree-of-freedom robotic arm. To consider the positional variety of the center of gravity caused by the motion of the robotic arm, the kinematic and dynamic models are built. Based on the presented models, a backstepping and sliding mode controller with a terminal sliding mode manifold is first applied to cope with the condition in which the robotic arm is motionless relative to the quadrotor. As the evolvement of the backstepping and sliding mode controller, a novel adaptive backstepping and sliding mode controller is then designed for the vehicle with the robotic arm wavering. The robustness and effectiveness of the proposed control law are investigated through both simulations and flight tests. With the proposed control laws, several simulations are conducted in conditions of both a variable and a constant center of gravity, and the performance of hovering is tested with a variable center of gravity in an experiment. Overall results show that the proposed adaptive backstepping control could estimate and compensate the variable center of gravity which may seriously influence the stabilization of quadrotor flying in the air.

7-DOF Cable-Driven Humanoid Robotic Arm

2011 ◽  
Author(s):  
Jun Ding ◽  
Robert L. Williams
Keyword(s):  
Linear Programming ◽  
Robotic Arm ◽  
Kinematics And Dynamics ◽  
Dynamics Analysis ◽  
Kinematics Analysis ◽  
End Effector ◽  
Motion Range ◽  
Potential Benefits ◽  
Redundant Mechanism ◽  
Joint Limits

The purpose of this paper is to study a 7-DOF humanoid cable-driven robotic arm, implement kinematics and dynamics analysis, present different cable-driven designs and evaluate their merits and drawbacks. Since this is a redundant mechanism, kinematics optimization is used to avoid joint limits, singularities and obstacles. Cable kinematics analysis studies the relationships between cable length and the end-effector pose. This is a design modified from the literature. Several new designs are compared in pseudostatics analysis of the arm and a favorable design is suggested in terms of motion range and the cable tensions. Linear programming is used to optimize cable tensions. Dynamics analysis shows that the energy consumption of a cable-driven arm is much less than that of traditional motor-driven arm. Cable-driven robots have potential benefits but also some limitations.

Equivalent Kinematic Chains of Three Degree-of-Freedom Tripod Mechanisms With Planar-Spherical Bonds

2005 ◽  
Vol 127 (1) ◽  
pp. 95-102 ◽  
Author(s):  
Patrick Huynh ◽  
Jacques M. Herve´
Keyword(s):  
Closed Loop ◽  
Degree Of Freedom ◽  
Robotic Device ◽  
Kinematics Analysis ◽  
Closed Loop System ◽  
Short Introduction ◽  
Kinematic Chains ◽  
Displacement Group ◽  
Three Degree Of Freedom ◽  
Moving Spheres

The paper aims to analyze the equivalent kinematic chains of a family of three-degree-of-freedom (3-DOF) tripod mechanisms with planar-spherical bonds in order to determine the platform motions generated by the mechanisms, and then to develop a prototype of a 3-DOF 3-RPS type parallel mechanism, which can be used as a wrist robotic device. After a short introduction to mechanical generators of Lie subgroups of displacement, the mobility formula of a general 3-DOF tripod mechanism based on the modified Gru¨ebler’s criterion is given. Using displacement group theory theorems, the analyzed closed-loop system becomes finally equivalent to three contacts between a rigid assembly of three moving spheres onto three fixed planes. As an application of the above method, a prototype mechanism is designed and fabricated based on the kinematics analysis, the force capability and the simplicity.

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