A New 6 DOF Robotic Arm with Linkage Motion Mechanism and Actuators Placed in Base

<p>We examined mechanism design and kinematic simulation of a new six degrees of freedom (DOF) robotic arm with rotational joints and a linkage motion mechanism. In the design, a parallel linkage mechanism, accompanied by an additional set of bevel gears, was used to create the desired motion for all six links along with transfer of all actuators to the robot’s base to reduce the mass of most of the arms. These changes resulted in reduction of the torque required for joints 1, 2, and 3. Using this parallel mechanism ensures dependence to motion links and creates a special case for the control of the robot and more rigidity against unwanted movement. Initially, we examined mechanism design methods for a parallel linkage mechanism and considered methods for application in an operational robot. In the next step, we determined the kinematic relationships that were established between the robot’s actuators and joints spaces due to the use of this mechanism. Then, we developed an example of the robot’s function in a performance simulation. The simulation results indicated that the mechanism and controller performance were acceptable.</p>

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Kinematics Analysis and Jacobian calculation for six Degrees of Freedom Robotic Arm

2020 IEEE 17th India Council International Conference (INDICON) ◽

10.1109/indicon49873.2020.9342093 ◽

2020 ◽

Author(s):

Manpreet Kaur ◽

Swati Sondhi ◽

Venkata Karteek Yanumula

Keyword(s):

Degrees Of Freedom ◽

Robotic Arm ◽

Kinematics Analysis ◽

Six Degrees Of Freedom

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Inverse Kinematic Problem of Movement of Six Degrees of Freedom Robotic Arm (Solved by a Numerical Method)

IOP Conference Series Materials Science and Engineering ◽

10.1088/1757-899x/709/3/033095 ◽

2020 ◽

Vol 709 ◽

pp. 033095

Author(s):

A V Kochetkov ◽

P M Salov ◽

O V Zakharov

Keyword(s):

Numerical Method ◽

Degrees Of Freedom ◽

Inverse Kinematic ◽

Robotic Arm ◽

Inverse Kinematic Problem ◽

Six Degrees Of Freedom

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Sequential Time-Optimal Algorithm for Extended Path Tracking Problem

Journal of Dynamic Systems Measurement and Control ◽

10.1115/1.4046614 ◽

2020 ◽

Vol 142 (8) ◽

Author(s):

Gábor Csorvási ◽

István Vajk

Keyword(s):

Degrees Of Freedom ◽

Optimal Algorithm ◽

Real Life ◽

Path Tracking ◽

Robotic Arm ◽

Tracking Problem ◽

Six Degrees Of Freedom ◽

Time Optimal ◽

Path Tracking Algorithm ◽

Extended Path

Abstract This paper presents a fast and easily implementable path tracking algorithm for robots. Usually, for a path tracking problem, the goal is to move the robot on a predefined path, while the joint velocities and accelerations are kept within their limits. This paper deals with the extended case, constraining the forces applied to the objects at the manipulator. First, a problem with a special set of constraints is presented, and a sequential solver method is formulated. The presented sequential solver algorithm has significant computational benefits compared to the direct transcription approach. Then, a practical example is introduced where the proposed algorithm can be applied. At last, the algorithm is validated by real-life experimental results with a six degrees-of-freedom robotic arm.

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Development of a Robotic Arm for Automated Harvesting of Asparagus

European Journal of Agriculture and Food Sciences ◽

10.24018/ejfood.2020.2.1.18 ◽

2020 ◽

Vol 2 (1) ◽

Author(s):

Yuki Funami ◽

Shinji Kawakura ◽

Kotaro Tadano

Keyword(s):

Input Data ◽

Degrees Of Freedom ◽

Robotic Arm ◽

Pneumatic Cylinder ◽

Agricultural Crops ◽

Robot Arm ◽

Linkage Mechanism ◽

Robot System ◽

Wheeled Robot ◽

Agricultural Setting

We designed and developed an original arm-robot system that harvests asparagus in both outdoor and indoor agricultural fields. Using the system, we carried out harvesting work automatically with input data related to asparagus vegetation in restricted settings. The developed fixed-site (non-wheeled) robot can reach out its arm to a stem of asparagus from a passage between two ridges on cultivated farmland without touching non-target stems or requiring changes to the farm conditions. Additionally, the hand at the tip of the arm stably grasps, cuts, harvests, and throws the stem it into a specific bag made for the gathering of agricultural crops. In mechanical terms, our originally developed robot arm has four degrees of freedom and is driven by motors. It harvests target asparagus stems without coming into contact with other objects in an agricultural setting, and the hand using the linkage mechanism of a pneumatic cylinder driven by air pressure, can hold the stem firmly and cut it. Our repetitive verification experiments showed that the mechanism is sufficiently accurate. The present study confirmed the robot arm system could be used for automatically harvesting asparagus, and the system was endorsed by several farmers. Moreover, we carried out experiments of harvesting asparagus on actual outdoor land and successfully harvested three stems sequentially under the condition that the operator obtained the positional coordinates earlier.

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Geometric synthesis of spatial parallel manipulators with fewer than six degrees of freedom

Proceedings of the Institution of Mechanical Engineers Part C Journal of Mechanical Engineering Science ◽

10.1243/095440602321029418 ◽

2002 ◽

Vol 216 (12) ◽

pp. 1175-1185 ◽

Cited By ~ 31

Author(s):

T S Zhao ◽

J S Dai ◽

Z Huang

Keyword(s):

Mechanism Design ◽

Degrees Of Freedom ◽

Screw Theory ◽

Algebraic Approach ◽

Structural Complexity ◽

Parallel Manipulators ◽

Parallel Mechanisms ◽

Kinematic Pair ◽

Type Synthesis ◽

Six Degrees Of Freedom

Manipulators with fewer than six degrees of freedom meet specific tasks and have the advantage of reducing structural complexity, design redundancy and cost. In order to construct parallel manipulators for given tasks, this paper develops an algebraic approach to type synthesis of spatial parallel mechanisms with fewer than six degrees of freedom based on the screw theory. With the proposed steps (i.e. describing restraining screws, identifying basic kinematic pair (KP) screws reciprocal to the restraining screws, linearly transforming the basic KP screws to obtain equivalent serial limbs and allocating the serial limbs) new parallel mechanisms can be constructed. The approach converts a mechanism design into a screw algebra operation, in which screws describe kinematic pairs and constraints between links. As examples, synthesis procedures of parallel mechanisms with four degrees of freedom are given, from which five novel parallel mechanisms result.

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Integrating laser profile sensor to an industrial robotic arm for improving quality inspection in manufacturing processes

Proceedings of the Institution of Mechanical Engineers Part C Journal of Mechanical Engineering Science ◽

10.1177/0954406220942552 ◽

2020 ◽

pp. 095440622094255

Author(s):

Toufik Al Khawli ◽

Muddasar Anwar ◽

Dongming Gan ◽

Shafiqul Islam

Keyword(s):

Degrees Of Freedom ◽

Ground Truth ◽

Calibration Procedure ◽

Robotic Arm ◽

Manufacturing Processes ◽

Quality Inspection ◽

Six Degrees Of Freedom ◽

Tool Positioning ◽

Sharp Object ◽

Laser Profile

This paper investigates the integration of laser profile sensor to an industrial robotic arm for automating the quality inspection in manufacturing processes that requires a manual labour intensive work. The aim was to register the measurements from a laser profile sensor mounted on a six degrees-of-freedom robot with respect to the robot base frame. The registration is based on a six degrees-of-freedom calibration, which is an essential step for several automated manufacturing processes that require high level of accuracy in tool positioning and alignment on one hand, and quality inspection systems that require flexibility and accurate measurements on the other hand. The investigation compromises of two calibration procedures namely the calibration using a sharp object and the planar constraints. The solution of the calibration procedures estimated from both iterative and optimization solvers is thoroughly discussed. By implementing a simulation platform that generates virtual data for the two procedures with additional levels of noise, the six-dimensional poses are estimated and compared to the ground truth. Finally, an experimental test using a laser profile from Acuity mounted on Mitsubishi RV-6SDL manipulator is presented to investigate the measurement accuracy with four estimated laser poses. The calibration procedure using a sharp object shows the most accurate simulation and experimental results under the effect of noise.

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Inverse Kinematics Data Adaptation to Non-Standard Modular Robotic Arm Consisting of Unique Rotational Modules

Applied Sciences ◽

10.3390/app11031203 ◽

2021 ◽

Vol 11 (3) ◽

pp. 1203

Author(s):

Štefan Ondočko ◽

Jozef Svetlík ◽

Michal Šašala ◽

Zdenko Bobovský ◽

Tomáš Stejskal ◽

...

Keyword(s):

Inverse Kinematics ◽

Degrees Of Freedom ◽

Structural Changes ◽

Kinematic Chain ◽

Building Blocks ◽

Robotic Arm ◽

Six Degrees Of Freedom ◽

Coordinate Vector ◽

Mathematical Equations ◽

The Individual

The paper describes the original robotic arm designed by our team kinematic design consisting of universal rotational modules (URM). The philosophy of modularity plays quite an important role when it comes to this mechanism since the individual modules will be the building blocks of the entire robotic arm. This is a serial kinematic chain with six degrees of freedom of unlimited rotation. It was modeled in three different environments to obtain the necessary visualizations, data, measurements, structural changes measurements and structural changes. In the environment of the CoppeliaSim Edu, it was constructed mainly to obtain the joints coordinates matching the description of a certain spatial trajectory with an option to test the software potential in future inverse task calculations. In Matlab, the model was constructed to check the mathematical equations in the area of kinematics, the model’s simulations of movements, and to test the numerical calculations of the inverse kinematics. Since the equipment at hand is subject to constant development, its model can also be found in SolidWorks. Thus, the model’s existence in those three environments has enabled us to compare the data and check the models’ structural designs. In Matlab and SolidWorks, we worked with the data imported on joints coordinates, necessitating overcoming certain problems related to calculations of the inverse kinematics. The objective was to compare the results, especially in terms of the position kinematics in Matlab and SolidWorks, provided the initial joint coordinate vector was the same.

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