Kinematics, Workspace, and Singularity Analysis of a Parallel Robot With Five Operation Modes (original) (raw)
Related papers
Kinematics and Workspace Analysis of a Novel 3-DOF Spatial Parallel Robot
Presented in ICEE 2011 - The 19th Iranian Conference on Electrical Engineering In this study, kinematics design and workspace analysis of a novel spatial parallel mechanism is elaborated. The proposed mechanism is to be exploited in a hybrid serial parallel mobile robot to fulfill stable motion of the robotic system when handling heavy objects by a serial manipulator mounted on the parallel mechanism. In fact, this parallel mechanism has been designed to obtain an appropriate maneuverability and fulfill the tipover stability of a hybrid serial-parallel mobile robotic system after grasping heavy objects. The proposed mechanism is made of three legs while each leg has one active degree of freedom (DOF) so that the mechanism contains 3-DOF. In order to investigate this novel parallel mechanism, inverse and forward kinematics model is developed and verified using two maneuvers. Next, the workspace of the manipulator is demonstrated symbolically, besides a numerical analysis will be studied. Finally, the advantages of exploiting such a parallel manipulator are discussed in order to be used in a hybrid serial-parallel mobile robotic system.
Influence of design parameters on the singularities and workspace of a 3-RPS parallel robot
Transactions of the Canadian Society for Mechanical Engineering, 2018
This paper presents variations in the workspace, singularities, and joint space with respect to design parameter k, which is the ratio of the dimensions of the mobile platform to the dimensions of the base of a 3-RPS parallel manipulator. The influence of the design parameters on parasitic motion, which is important when selecting a manipulator for a desired task, is also studied. The cylindrical algebraic decomposition method and Gröbner-based computations are used to model the workspace and joint space with parallel singularities in 2R1T (two rotational and one translational) and 3T (three translational) projection spaces, where the orientation of the mobile platform is represented using quaternions. These computations are useful in selecting the optimum value for the design parameter k such that the parasitic motions can be limited to specific values. Three designs of the 3-RPS parallel robot, based on different values of k, are analyzed.
A study of workspace and singularity characteristics for design of 3-DOF planar parallel robots
The International Journal of Advanced Manufacturing Technology, 2010
A study of workspace and singularity characteristics is presented for two common types of 3-DOF planar parallel robot manipulators. The robots considered feature a kinematic structure with three in-parallel actuated, R-R-R, and R-P-R serial chain geometries. In this study, computer simulations aided with graphic visualization were used to characterize the complete pose workspace (for ranges of both position and orientation) and the singularity inherent to the systems. Parametric studies have also been performed to ascertain the way in which both characteristics vary with respect to various geometric parameters such as pivot locations, link lengths, and size of end-effector. Results are shown by way of a unique composite ratio of the available workspace to the density of singularity within that workspace, which can be used to optimize the geometry of the robots in design.
Workspace and Joint Space Analysis of the 3-RPS Parallel Robot
Volume 5A: 38th Mechanisms and Robotics Conference, 2014
The Accurate calculation of the workspace and joint space for 3 RPS parallel robotic manipulator is a highly addressed research work across the world. Researchers have proposed a variety of methods to calculate these parameters. In the present context a cylindrical algebraic decomposition based method is proposed to model the workspace and joint space. It is a well know feature that this robot admits two operation modes. We are able to find out the set in the joint space with a constant number of solutions for the direct kinematic problem and the locus of the cusp points for the both operation mode. The characteristic surfaces are also computed to define the uniqueness domains in the workspace. A simple 3-RPS parallel with similar base and mobile platform is used to illustrate this method.
Journal of Mechanisms and Robotics, 2017
A novel parallel robot, dubbed the SDelta, is the subject of this paper. SDelta is a simpler alternative to both the well-known Stewart–Gough platform (SGP) and current three-limb, full-mobility parallel robots, as it contains fewer components and all its motors are located on the base. This reduces the inertial load on the system, making it a good candidate for high-speed operations. SDelta features a symmetric structure; its forward-displacement analysis leads to a system of three quadratic equations in three unknowns, which admits up to eight solutions, or half the number of those admitted by the SGP. The kinematic analysis, undertaken with a geometrical method based on screw theory, leads to two Jacobian matrices, whose singularity conditions are investigated. Instead of using the determinant of a 6 × 6 matrix, we derive one simple expression that characterizes the singularity condition. This approach is also applicable to a large number of parallel robots whose six actuation wr...
296 Novel Design of a 4 DOF Parallel Robot
regional-robotics.org
This work illustrates the novel design of a unique 4 degree-of -freedom parallel robot with 3 DOF in translation and one DOF in rotation. The forward and inverse kinematics will be detailed including the analysis of the singularities of the mechanism. The extensive simulation of the system is proposed. The design methodology shows the advantage over the other conventional method in less complexity of the direct kinematics solutions which can be extended to 5 or 6 DOF parallel robot. The purpose configuration can be applied to the rapid prototype application and also the 5-axis milling machine for advance manufacturing application.
Workspace and singularity analysis of 3-RRR planar parallel manipulator
Nowadays, Planar Parallel Manipulators (PPMs) are widely used due to many inherent characteristics over the serial manipulator. In this paper, PPM with 3-RRR (revolute joints) configuration is simulated using Pro/mechanism and investigated analytically. Revolute joints are considered as joints with virtually no mechanical limits so that the workspace can be maximized. Loop closure equations are formulated for the 3-RRR manipulator and Jacobian matrices are developed for singularity analysis. For the proposed mechanism, singularity analysis is carried out using Instantaneous Center of Rotation (ICR) method. With regard to planar parallel manipulators, singularity can be classified into three groups based on properties of instantaneous center of rotation. This method is very fast and can easily be applied to the manipulators under study. The results of ICR are compared using analytical approach. Functional workspace of planar parallel manipulator is developed by actuating different combination of servomotors and is often limited because of interference among their mechanical components.
Comparative Analysis in Dynamics of the 3-RRR Planar Parallel Robot
Proceedings of the Romanian Academy - Series A: Mathematics, Physics, Technical Sciences, Information Science
Matrix relations for kinematics and inverse dynamics of the 3-RRR planar parallel robot are established in this paper. Three identical planar legs connecting to the moving platform are located in the same plane. Knowing the general motion of the platform, we develop first the inverse kinematics problem and determine the positions, velocities and accelerations of the robot's elements. The inverse dynamics problem is solved using the principle of virtual work, but it has been verified the results in the framework of the Lagrange equations with multipliers. Recursive equations offer expressions and graphs for the input powers of three revolute actuators and the internal forces in the joints. A of joint k m k J – mass and symmetric matrix of tensor of inertia of k T about the link-frame k k k z y x 10 10 10 , , A B C p p p – powers of three fixed revolute actuators 1. INTRODUCTION Compared with serial manipulators, the followings are the potential advantages of parallel robots: high...
Workspace Analysis of a New Parallel Manipulator
1999
This paper studies the workspace of a six-DC)F parallel manipulator of three-PPSR (prismatic-prismaticspheric-revolute) type. It is well recognized that the most significant drawback of parallel manipulators is their limited workspace. To develop new parallel mechanisms with a larger workspace is of interest to additional applications. The mechanism of the three-PPSR manipulator and its variations are briefly analyzed first. The workspace is then determined and the effects of joint limit and limb interference constraints on the workspace shape and size are studied. The constituent regions of the workspace corresponding to different classes of manipulator poses are discussed. It is shown that the workspace of this parallel manipulator is larger than that of a comparable Stewart platform especially in the vertical direction.