Questions tagged [manipulator]
manipulator is a device used to manipulate materials without direct contact.
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Why does the Denavit-Hartenberg representation fail to capture the length of the last link in my model?
The length of the last link (1.73) of my model (of a human finger) is not represented in any of the parameters that I calculated using the Denavit-Hartenberg algorithm, which I think can't be right. I ...
user18408
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How to check reachability of manipulator to a point?
I have written a MATLAB code for inverse kinematics of 3R robotic arm, which returns value of joint angles for given link lengths and end effector position and orientation. But if location of point is ...
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Optimization of link lengths for 3R serial manipulator
I am trying to formulate an optimization problem for determining link lengths of 3R manipulator shown in picture below,
Following are the constraints,
Robot arm should be reachable at point x = 100, ...
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How can serial manipulator have unique condition number for given end effector position?
I am reading about Condition Number which is considered as measure of manipulability of robotic arm, it is defined as
$$
k = \parallel J \parallel \parallel J^{-1} \parallel
$$
Where,
$$
\parallel J \...
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Validation of dh parameters
I am working on a concept of robotic arm for which I have fixed DH frames and parameters. Is there any way to validate the correctness of DH parameters and frames ?
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how to make a configuration space of a robot manipulator?
How to make a configuration space of a robot manipulator from a work space ? it's robot manipulator is 3 degree of freedom. Is a robot manipulator with more degrees of freedom the same process ?. Do ...
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Euler-Lagrange Dynamic model
I'm working on a masters thesis and need to calculate Mass inertia matrix ($M$), Coriolis/Centrifugal matrix ($C$), and the gravity matrix ($G$) in the equation $M\ddot{\theta} + C\theta + G = \tau$ (...
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forward and inverse kinematics of arm
I'm trying to figure out to a problem with a planar manipulator.
The manipulator has a base effector and L1 and L2 with 3 joints.
Question: INVERSE KINEMATICS
Given the ...
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Calculating the singular configuration of a 3 revolute joint manipulator
I would really appreciate it if somebody could help me calculate the singular configuration of this simple manipulator
I am confused since J is a 2x3 matrix and I cannot simply calculate the ...
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Is it possible to control joint torque using the position input and torque feedback?
So I am working with a UR10 manipulator which doesn't have a direct torque interface. However, it provides torque/velocity/position feedback for each joint as well as position/velocity interfaces for ...
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DH parameters of a PUMA-type manipulator
I'm struggling to find the DH parameters for this PUMA-type manipulator that yield the same results as the author (1):
The way I'm checking if the parameters I have are correct is by comparing the ...
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Symbolic Representaion of Links and Joints: How to sketch complex manipulators using simple symbols?
In some papers and books we can see that authors using symbols to represent robot arms. My question is, is there a convention for such sketches? If so could you provide a reference which shows how ...
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Different methods to determine DOF: Chebychev-Kutzbach-Grubler method vs. Screw method
I'm familiar with Chebychev-Kutzbach-Grubler method to determine degree of freedom of a robot arm. But it seems this method fails to calculate the mobility of some parallel robots, as explained here.
...
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Robot Graphical Representation in Real Time
I'm working with a robot intended to be placed in a tele-echography environment. To control the robot I'm using a 6D space mouse that control each degree of freedom of the robot. However, since the ...
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Are scissors what I want for moving straight up and out?
I'm a programmer. I had a tiny amount of experience building robots in college a few years ago, but haven't done anything since.
I'd like to build a robot that can move around my house, pick items up ...
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Dynamics of a 3R planar robot manipulator,matrices M(q),C(q,q') and G(q)
The dynamics equation is T=M(q)*q''+C(q,q')*q'+G(q).
Can somebody provide me with the M(q), C(q,q') and G(q) matrices of a 3R manipulator with link mass,length and rotational inertia m_i, l_i and ...
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How to use RL (Robotics Library) with Xcode?
I came across RL to program robotic manipulators. But according to the website, currently supported websites are Ubuntu and Windows only. Since Ubuntu and Mac OS are based on UNIX kernel, is it ...
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Cloth (non-rigid body) manipulation with computer vision? [closed]
I am currently working on a prototype device to automate cloth ironing task. So basically the mechanical design involves 4 manipulators and a separate manipulator arm with a hot pad (iron) to ...
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How to decide links length of manipulator?
I'm working on pick and place robotic arm with 4 dof. I'm using MATLAB for inverse kinematics. But, I want to know how to decide links length. Say, I have four point in space upto where my robotic arm ...
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Generating IK solution for use in MoveIT for 5 DOF arm
I am working on a custom 5 DOF arm(image at the bottom). I have generated the URDF, the MoveIt configs etc for it.
I want to have the basic IK, planning and collision detection features of MoveIt. ...
t27
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Integrating Forward Kinematics Map
Let the forward kinematics map be denoted by $\mathcal{F}$ such that
$\mathcal{F}: \theta \in \mathbb{R}^{n} \rightarrow g \in SE3$
Let the minimal representation of $g$ be given by $x \in \mathbb{R}...
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showing error while using inverse kinematics "ikine" for 4 dof robotic arm
I want to do forward dynamics but before that I got struck in inverse kinematics for 4 dof. My code is given below:
...
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ROS Answers SE migration: manipulator
hi there. i want to make a manipulator either 6 DOF or 3 DOF. is there any packages/tutorial available for ROS indigo version ????
Originally posted by Arpitsoni on ROS Answers with karma: 9 on 2016-...
Arpitsoni
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Pick and place using only vision information and forward kinematics [closed]
Is it possible to do pick and place tasks using only forward kinematics and object detection information from a camera?
I want to avoid having to do inverse kinematic calculations for my robot. Is ...
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Dealing with fixed transformations while solving inverse kinematics
I am trying to solve inverse kinematics (using the Jacobian pseudoinverse method) for a 7 DoF arm, but because of the way the robot is mounted, the base frame does not coincide with the frame of the ...
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Inverse kinematics: how to specify TCP constraints in an iterative algorithm?
I am trying to write some simple code to perform IK for a 6 DoF redundant robot using the Jacobian pseudo-inverse method. I can solve IK for a desired pose using the iterative method, and I want to ...
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Recommendations for a hardy, IP67 arm
Hi,
I'm looking for an IP67 arm for a mobile robot in a harsh environment. Some other wishes are:
ROS compatability
Small controller (must fit on a ~900mm x 900mm platform)
Reach >500mm
At least 5 ...
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how to manipulate arm robot? [closed]
I want to make a robot arm with a gripper that can go to any x y z coordinates near it. the robot itself will be simple just servo motors and Arduino but I don't know how to make reach the desired ...
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Dynamic torque simulation for a 6 DOF robotic arm
I am working on a 6 DOF robotic arm(industrial manipulator). I have the basic structural specs (dimensions, weights etc) for the links and joints with me.
Basically, I want to simulate both static ...
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Rostock Delta Robot 3D Printer Degrees of Freedom (DOF)
What is the degrees of freedom (DOF) of the Rostock delta robot 3d printer (delta mechanism that consists of three prismatic joints)?
Here's the link to the delta mechanism I'm referring to:
https://...
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Computing the Jacobian Matrix -- chain rule?
I am learning about robot kinematics and the Jacobian matrix, and I'm trying to understand how to compute the Jacobian matrix given a kinematic chain, such as a robot arm. I understand the theory ...
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Difference between Degrees of Freedom (DOF) and Degrees of Motion (DOM)
What is a difference between degrees of freedom (DOF) and degrees of motion (DOM)? I know that DOF is the number of independent movements a manipulation arm can make and robot system can have max 6 ...
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Anthropomorphic Arm
I developed an anthropomorphic arm (structure in aluminium) with 6 DOF (3 plus spherical wrist) for direct kinematic.
I chose magnetic rotary encoders to measure angles but I am not satisfied, due ...
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Best way to use Moveit for teleoperation?
I've seen this topic discussed a bit here, and on the MoveIt! mailing list here and here, but those conversations are pretty old now and I'm wondering if there is a clearer answer now.
I have a 7 DOF ...
Airuno2L
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UR5 - Gazebo Joint Position controller
Dear all,
I need to simulate a velocity control of a UR5 robot in Gazebo + ROS. But current packages of UR only has a joint trajectory controller, But I want to control individual joint velocities ...
dinesh_sl
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Robotic manipulator Jacobian by product of exponentials
I've taken a class and started a thesis on robotics and my reference for calculating the Jacobian by product of exponentials seems incorrect, see:
http://www.cds.caltech.edu/~murray/books/MLS/pdf/...
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Optimal trajectory for manipulators using optimal control
I'm trying to implement direct-multiple shooting method to my problem.
...
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Calculate required motor torque through Harmonic Drive
I have a term project which is controlling a two-link manipulator with harmonic drive installed at each joint.
To control, i used Computed control method to determine the torque needed for each joints ...
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what could be the process flow for trajectory planning of 6DOF manipulator using arduino?
hi,
i want to make exactly what this video shows - https://www.youtube.com/watch?v=IfP6J9Bxt2w . can anybody tell me how to interlink arduino with ros? which tutorial i need to study? i've just ...
baiju
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7DOF inverse kinematics spherical wrist
Is it possible to apply kinematic decoupling for a 7 DOF 7R manipulator with spherical wrist? If it is possible, can anyone suggest a reference on how to apply this approach with a redundant ...
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Human arm inverse kinematics
Hi I want to implement an human arm robot and a task such as moving a glass between two points using Robotic Toolbox for Matlab by Peter Coorke. I'm a student and I'm a newbie in this kind of things ...
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How to find the body jacobain, for each link in a robot manipulator?
The links twist could be obtained, and thus The spatial manipulator Jacobian could be done, but when it comes to the body Jacobian, it is becomes difficult. Moreover, the adjoint transformation ...
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Can a Jacobian be used to determine required joint angles for end effector velocity/position?
I'm in the early stages of working with a simple robot arm, and learning about the Jacobian and inverse kinematics.
From my understanding, the Jacobian can be used to determine the linear and angular ...
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Implementing a torque-controlled method on a position-controlled robot
I am working with a position-controlled manipulator. However, I want to implement a torque-controlled method on this robot. Is there any way to convert a torque command to a position command?
I try ...
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Proportional controller error doesn't approach zero
I'm reading this pdf. The dynamic equation of one arm is provided which is
$$
l \ddot{\theta} + d \dot{\theta} + mgL sin(\theta) = \tau
$$
where
$\theta$ : joint variable.
$\tau$ : joint torque
...
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Short distance ball transport
I'm looking for a way to transport balls (diameter 50mm) 220 mm up with over a slope with a length of 120 mm. Currently I'm considering the usage of a belt system but I cannot seem to find a good belt ...
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Static equilibrium for 7 dof manipulator
I have a 7 dof manipulator (Kuka LBR4+) and would like to calculate the joint torques needed to keep the arm in a static equilibrium. In most books the transposed jacobian is used to map the forces ...
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Computing inverse kinematic with jacobian matrices for 6 dof manipulator
I'm trying to calculate the inverse kinematic for an 6 dof manipulator.
Task:
A target point $p_{target} = (x,y,z)^T$ and the orientation $o_{target} = (a, b, c)^T$ are given and I want to get the ...
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VAL language and velocity control of industrial robot
In my bachelor, I programmed CNC machines. Now, working with an Industrial robot arm, I learn that their programming languages are mostly similar. VAL is a typical example, for instance:
...
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Dynamics of parallel manipulator
My task is to apply forces to control 3-dof parallel manipulator. Forces are applied to linear actuators, friction is neglected. End-effector of a robot is supposed to follow generated path; for ...
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