Optimal Kinematic Design of Gantry Parallel Robots

2005 ◽  
Author(s):  
Viktor Berbyuk ◽  
Lars Johannesson
Keyword(s):  
Degrees Of Freedom ◽  
Parallel Robot ◽  
Parallel Robots ◽  
Objective Functions ◽  
Kinematic Design ◽  
Parallel Structures ◽  
The Difference ◽  
The Relationship ◽  
Kinematic Properties ◽  
Conditioning Number

This paper addresses some issues of optimal kinematic design of parallel robot with 3 degrees of freedom. Robot performs translational gantry type motion with a large workspace. The structure’s nominal kinematics is identical to the Linear Delta Robot, the difference being the way which the links are organized. In order to yield a design of the Gantry Parallel Robot with a large workspace volume and good kinematic properties, multi-criteria optimization is used. The objective functions comprise a space utilization index and the inverse conditioning number of the Jacobian matrix. Three different geometrical layouts of the robot are examined and the Pareto optimality between the objective functions is found for several different cases. Pareto-optimal curves showing the relationship between the workspace size and the manipulability are presented as a tool for the designer. The obtained results give a good overview of the kinematic properties of the Gantry Parallel Robot that can be used for designing the parallel structures for various applications.

scholarly journals Cable-Driven Parallel Robot with Reconfigurable End Effector Controlled with a Compliant Actuator

Sensors ◽  
2018 ◽  
Vol 18 (9) ◽  
pp. 2765 ◽  
Author(s):  
Alejandro Rodriguez-Barroso ◽  
Roque Saltaren ◽  
Gerardo A. Portilla ◽  
Juan S. Cely ◽  
Marco Carpio
Keyword(s):  
Degrees Of Freedom ◽  
Parallel Robot ◽  
Parallel Robots ◽  
Degree Of Freedom ◽  
Elastic Model ◽  
Dynamic Simulations ◽  
End Effector ◽  
High Tension ◽  
Compliant Actuator ◽  
The Relationship

Redundancy in cable-driven parallel robots provides additional degrees of freedom that can be used to achieve different objectives. In this robot, this degree of freedom is used to act on a reconfigurable end effector with one degree of freedom. A compliant actuator actuated by one motor exerts force on both bodies of the platform. Due to the high tension that appears in this cable in comparison with the rest of the cables, an elastic model was developed for solving the kinestostatic and wrench analysis. A linear sensor was used in one branch of this cable mechanism to provide the needed intermediate values. The position of one link of the platform was fixed in order to focus this analysis on the relationship between the cables and the platform’s internal movement. Position values of the reconfigurable end effector were calculated and measured as well as the tension at different regions of the compliant actuator. The theoretical values were compared with dynamic simulations and real prototype results.

Modelling and Simulation of a Isoglide T3R1 Parallel Robot

2010 ◽  
Vol 166-167 ◽  
pp. 457-462
Author(s):  
Dan Verdes ◽  
Radu Balan ◽  
Máthé Koppány
Keyword(s):  
High Speed ◽  
Degrees Of Freedom ◽  
Parallel Robot ◽  
Parallel Robots ◽  
Practical Implementation ◽  
Medical Robots ◽  
The Past ◽  
And Control ◽  
Workspace Design ◽  
Human Systems

Parallel robots find many applications in human-systems interaction, medical robots, rehabilitation, exoskeletons, to name a few. These applications are characterized by many imperatives, with robust precision and dynamic workspace computation as the two ultimate ones. This paper presents kinematic analysis, workspace, design and control to 3 degrees of freedom (DOF) parallel robots. Parallel robots have received considerable attention from both researchers and manufacturers over the past years because of their potential for high stiffness, low inertia and high speed capability. Therefore, the 3 DOF translation parallel robots provide high potential and good prospects for their practical implementation in human-systems interaction.

Type synthesis of coordinated multi-robot system based on parallel thought

2018 ◽  
Vol 42 (2) ◽  
pp. 164-176 ◽  
Author(s):  
Wanqiang Xi ◽  
Bai Chen ◽  
Yaoyao Wang ◽  
Feng Ju
Keyword(s):  
Degrees Of Freedom ◽  
Screw Theory ◽  
Parallel Robot ◽  
Parallel Robots ◽  
Type Synthesis ◽  
World Coordinate System ◽  
Coordination System ◽  
Branched Chain ◽  
Branched Chains ◽  
Multi Robot

For the synthesis of the required type about the multi-robot coordination system in industrial transportation, this paper presents a novel method in which each robot in the coordinated task is viewed as a branched chain of an equivalent parallel robot (EPR), which is converted into a problem for type synthesis of parallel robots. A theoretic method is proposed to represent the kinematic features of the mechanism’s end-effector and its position and pose in the world coordinate system. The basic concept of a robotic characteristic (C) set is given, and the corresponding algorithm is analyzed. Based on the theory of C set, the concrete steps for type synthesis of EPR are presented by analyzing the characteristics of its branched chains, and many EPR groups with end kinematic features for the C sets of the operational tasks are obtained. Then three translational (3T) operational requirements that can be extended to other degrees of freedom (DOF) are adopted, and the DOF of homogeneous and heterogeneous EPR are analyzed using screw theory. Finally the validation of the method is demonstrated by Adams, which shows that the two groups are able to complete the task.

Kinematic Analysis of a Five-Legged Mobile Robot

2010 ◽  
Author(s):  
Muhammed R. Pac ◽  
Dan O. Popa
Keyword(s):  
Kinematic Analysis ◽  
Degrees Of Freedom ◽  
Parallel Robot ◽  
Parallel Robots ◽  
The Body ◽  
Legged Robots ◽  
Upper Body ◽  
Design Changes ◽  
Robot Performance ◽  
The Impact

Legged robots are more maneuverable, and can negotiate rough terrain much better than conventional locomotion using wheels. However, since the kinematic or dynamic analysis of such robots involves closed chains, it is typically more difficult to investigate the impact of design changes, such as the number, or the design of its legs, to robot performance. Most legged robots consist of 4 legs (quadrupeds) or 6 legs (hexapods). This paper discusses the kinematic analysis of an unconventional, symmetrical 5-legged robot with 2-DOF (Degrees Of Freedom) universal joints in each leg. The analysis was carried out in order to predict the mobility of the upper body platform, and investigate the number of robot actuators needed for mobility. The product of exponentials formulation with respect to the local coordinate frames is used to describe the twists of the joints. The analysis is based on the idea that the robot body platform along with the legs can be considered instantaneously as a parallel robot manipulating the ground. Hence, the analysis can be done using the Jacobian formulation of parallel robots. Simulation results confirm the mobility analysis that the robot can have at most 3-DOF for the body and that these freedoms are coupled rotations and translations in 3D space also with a dependence on the configuration of the robot.

Novel Deployable Mechanisms With Decoupled Degrees-of-Freedom

2015 ◽  
Vol 8 (2) ◽  
Author(s):  
Shengnan Lu ◽  
Dimiter Zlatanov ◽  
Xilun Ding ◽  
Rezia Molfino ◽  
Matteo Zoppi
Keyword(s):  
Degrees Of Freedom ◽  
Singularity Analysis ◽  
Degree Of Freedom ◽  
Three Dimensions ◽  
Potential Applications ◽  
Magnification Ratio ◽  
The Relationship ◽  
Kinematic Properties ◽  
Kinematic Simulations

A novel family of deployable mechanisms (DMs) is presented. Unlike most such devices, which have one degree-of-freedom (DOF), the proposed DM can be deployed and compacted independently in two or three directions. This widens the range of its potential applications, including flexible industrial fixtures and deployable tents. The mechanism's basic deployable unit (DU) is assembled by combining a scissor linkage and a Sarrus linkage. The kinematic properties of these two components and of the combined unit are analyzed. The conditions under which the unit can be maximally compacted and deployed are determined through singularity analysis. New 2DOF DMs are obtained by linking the DUs: each mechanism's shape can be modified in two directions. The relationship between the degree of overconstraint and the number of DUs is derived. The magnification ratio is calculated as a function of link thickness and the number of DUs. The idea of deployment in independent directions is then extended to three dimensions with a family of 3DOF mechanisms. Finally, kinematic simulations are performed to validate the proposed designs and analyses.

A Practical Fuzzy Adaptive Control Strategy for Multi-DOF Parallel Robot

2013 ◽  
Vol 347-350 ◽  
pp. 661-665 ◽  
Author(s):  
Wei Meng ◽  
Zu De Zhou ◽  
Quan Liu ◽  
Qing Song Ai
Keyword(s):  
Degrees Of Freedom ◽  
Fuzzy Inference ◽  
Control Strategies ◽  
Parallel Robot ◽  
Parallel Robots ◽  
Medical Rehabilitation ◽  
Position Tracking ◽  
Tracking Accuracy ◽  
Compact Structure ◽  
Fuzzy Adaptive

Multiple Degrees of Freedom (DOF) parallel robots possess the advantages of being compact structure, great stiffness, stability and high accuracy, so such platforms have been widely used in application areas as diverse as the spacecraft motion simulators, radio telescopes, and medical rehabilitation devices. In this paper, after giving a brief review on the control strategies for parallel robot, a 6-DOF robot system for medical purposes based on simulation as well as real environment is established. In order to improve the position tracking accuracy for such objects with time-varying and nonlinear parameters, a practical fuzzy adaptive controller is designed based on the kinematics of parallel platform, where fuzzy inference units are utilized to modify the PID parameters in real-time by using the position feedback from the robot actuators. Finally, both virtual and actual experiment results demonstrate that the proposed algorithm is able to effectively reduce the position tracking errors compared with the traditional PID controller, and the reliability and feasibility of such parallel robotic system can also be guaranteed.

Gateway Configuration for Rapid Pick-and-Place Operations of 2-Degrees-of-Freedom Parallel Robots

2020 ◽  
Vol 13 (1) ◽  
Author(s):  
Andrea Martin-Parra ◽  
David Rodriguez-Rosa ◽  
Sergio Juarez-Perez ◽  
Guillermo Rubio-Gomez ◽  
Antonio Gonzalez-Rodriguez ◽  
...  
Keyword(s):  
Energy Consumption ◽  
Degrees Of Freedom ◽  
Jacobian Matrix ◽  
Parallel Robots ◽  
End Effector ◽  
Joint Coordinates ◽  
Pick And Place ◽  
Low Energy Consumption ◽  
Simulation Results ◽  
The Difference

Abstract This article presents a new assembling for 2 degrees-of-freedom (DOFs) parallel robots for executing rapid pick-and-place operations with low energy consumption. A conventional design of 2-DOF parallel robots is based on five-bar mechanisms. Collisions between links are highly possible, restricting the end-effector workspace and/or increasing the trajectory time to avoid collisions. In this article, an alternative assembling for preventing collisions is presented. This novel assembling allows exploring the difference between the four five-bar mechanism configurations for the same position of the end-effector. Some of these configurations yield to lower time and/or lower energy consumption for the same motorization. First, a dynamic model of the robot has been developed using matlab® and simulink® and validated by comparison with the results obtained by adams® software. A robust cascade PD regulator for controlling joint coordinates has been tuned providing a high accurate end-effector positioning. Finally, simulation results of four configurations are presented for executing controlled maneuvers. The obtained results demonstrate that the conventional configuration is the worst one in terms of trajectory time or energy consumption and, conversely, the best one corresponds to an uncommonly used configuration. A workspace map where all configurations provide faster maneuvers has been obtained in terms of Jacobian matrix and mechanism elbows distance. The results presented here allow designing a rapid manipulator for pick-and-place operations.

Design Optimization of 6-HTRT Parallel Robot Orientated on Workspace

2003 ◽  
Author(s):  
Hui Yu ◽  
Jinsong Wang ◽  
Guanghong Duan ◽  
Lining Sun
Keyword(s):  
Design Optimization ◽  
Motion Control ◽  
Parallel Mechanism ◽  
Optimization Design ◽  
Optimization Method ◽  
Parallel Robot ◽  
Parallel Robots ◽  
Objective Functions ◽  
Restriction Factors

In this paper an optimization method based on the Mechanics of Parallel Robots and orientated on workspace is conducted in the construction of 6-HTRT parallel robot. By analyzing the characteristics of specific workspace and setting up objective functions, optimizations are implemented on the design of parallel robot. As a result of the optimization design, the parallel robot not only figures the minimum overall size of robot structural, but also has workspace unrestricted by the limit range of Hooke joint’s conical angles. The restriction factors on workspace of 6-HTRT parallel robot are reduced thus the algorithm for motion control of the robot is simplified and the performance of the parallel mechanism is improved.

scholarly journals Potential Energy Distribution of Redundant Cable-Driven Robot Applied to Compliant Grippers: Method and Computational Analysis

Sensors ◽  
2019 ◽  
Vol 19 (15) ◽  
pp. 3403 ◽  
Author(s):  
Rodriguez-Barroso ◽  
Saltaren ◽  
Portilla ◽  
Cely ◽  
Yakrangi
Keyword(s):  
Energy Distribution ◽  
Parallel Robot ◽  
Parallel Robots ◽  
Potential Energy Distribution ◽  
End Effector ◽  
Tension Distribution ◽  
Multibody Dynamic ◽  
Compliant Actuators ◽  
Dynamic Software ◽  
The Relationship

Cable-driven parallel robots with a redundant configuration have infinite solutions for their cable tension distribution to provide a specific wrench to the end-effector. Redundancy is commonly used to increase the workspace and stiffness or to achieve secondary objectives like energetic minimization or additional movements. This article presents a method based on energy distribution to handle the redundancy of cable-driven parallel robots. This method allows the deformation and tension of each link to be related to the total energy available in the parallel robot. The study of energy distribution expression allows deformation, tension, and position to be combined. It also defines the range of tension and deformation that cables can achieve without altering the wrench exerted on the end-effector. This range is used with a passive reconfigurable end-effector to control the position of two grippers attached to some cables which act as compliant actuators. The relationship between the actuators’ energy and their corresponding gripper positions is also provided. In this way, energy measurement from the actuators allows the grasping state to be sensed. The results are validated using multibody dynamic software.

DeltaBot: A New Cable-Based Ultra High Speed Robot

2003 ◽  
Author(s):  
Saeed Behzadipour ◽  
Robert Dekker ◽  
Amir Khajepour ◽  
Edmon Chan
Keyword(s):  
High Speed ◽  
Degrees Of Freedom ◽  
Manufacturing Industry ◽  
Design Procedure ◽  
Parallel Manipulators ◽  
Parallel Robot ◽  
Parallel Robots ◽  
Manufacturing Cost ◽  
End Effector ◽  
Serial Manipulators

The growing needs for high speed positioning devices in the automated manufacturing industry have been challenged by robotic science for more than two decades. Parallel manipulators have been widely used for this purpose due to their advantage of lower moving inertia over the conventional serial manipulators. Cable actuated parallel robots were introduced in 1980’s to reduce the moving inertia even further. In this work, a new cable-based parallel robot is introduced. For this robot, the cables are used not only to actuate the end-effector but also to apply the necessary kinematic constraints to provide three pure translational degrees of freedom. In order to maintain tension in the cables, a passive air cylinder is used to push the end-effector against the stationary platform. In addition to low moving inertia, the new design benefits from simplicity and low manufacturing cost by eliminating joints from the robot’s mechanism. The design procedure and the results of experiments will be discussed in the following.

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