Questions tagged [manipulator]
manipulator is a device used to manipulate materials without direct contact.
156
questions
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Significance of link length ratio in serial manipulator
I am formulating a problem to optimize link lengths of 3R serial manipulator shown below :
I do not assume any explicit relationship between the link lengths, but in one of the papers (http://www....
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1
answer
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D-H parameters verification
This robot has 2 revolute joints in advance then one cylindrical joint, then one revolute joint, then another cylindrical joint, then three revolute joints at the end.
There is no D-H table for that ...
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2
answers
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Understanding MoveIt! and OMPL more deeply
I wanted to know the actual mathematics behind the path planners MoveIt! uses for manipulators from OMPL. I tried to look into source codes but couldn't get enough details.
I wish to know:
How cost ...
0
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1
answer
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The weight on position constraint for link is near zero. Setting to 1.0
Hi,
While trying to move a robotic manipulator to a new pose (using MoveIt!), in order to move to the Next Best View of the manipulator's workspace using the YAK package, I repeatedly get this warning ...
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3
answers
866
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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
...
0
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1
answer
495
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Which motors are specifically used for UR3 (Universal robot arm) [closed]
I am looking for the specification of UR3, peak torque and rpm.
0
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1
answer
321
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zero-g mode for UR10 gravity compensation
I would like to freely move my UR10 arm in response to an external force, just like the zero-g mode for Baxter robot, which can be activated by holding its wrist. The Baxter documentation on zero-g ...
0
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1
answer
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REQUIRED process [open_manipulator_dynamixel_controller-2] has died!
I just tried to operate open manipulator system by using two motor(MX-106).
When I launch that code, the following error occur.
...
2
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1
answer
563
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Dynamics of a robot manipulator with a force acting on the end-effector
I have this exercise
The dynamic model is
$B(q)\ddot{q}+S(q,\dot{q})\dot{q}=\tau+\tau_k$
Where $B(q)$ is the inertia matrix, $S(q,\dot{q})\dot{q}$ are the centrifugal and Coriolis terms, $\tau$ is ...
1
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1
answer
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Urdf as a way to model dynamics?
Since urdf format serves the purpose of kinematic model but also extends for dynamical properties such as mass,moment of inertia and centre of masses, can it be considered a viable dynamical model of ...
2
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1
answer
731
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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, ...
1
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2
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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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1
answer
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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 \...
0
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1
answer
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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 ...
3
votes
1
answer
550
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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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2
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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 ...
2
votes
1
answer
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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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2
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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 ...
0
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1
answer
825
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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 ...
0
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1
answer
305
views
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 ...
1
vote
2
answers
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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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1
answer
91
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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 ...
0
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2
answers
158
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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 ...
0
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1
answer
255
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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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2
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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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1
answer
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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 ...
1
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0
answers
83
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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 ...
2
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3
answers
5k
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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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1
answer
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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 ...
0
votes
1
answer
9
views
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. ...
2
votes
1
answer
223
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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}...
2
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1
answer
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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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1
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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-...
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1
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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 ...
2
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2
answers
336
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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 ...
2
votes
2
answers
572
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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 ...
0
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3
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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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4
answers
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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 ...
1
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1
answer
530
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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://...
0
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1
answer
13
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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 ...
4
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1
answer
297
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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 ...
6
votes
2
answers
856
views
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 ...
0
votes
1
answer
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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 ...
2
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1
answer
766
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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 ...
3
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2
answers
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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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1
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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 ...
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1
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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 ...
0
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2
answers
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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 ...
6
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1
answer
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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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0
answers
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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:
...