Questions tagged [robotic-arm]
The arm tag is intended to be used for questions relating to robotic arms from, small hobby arms with only 1 or 2 degrees of freedom to large industrial robots with complex joint assemblies. For the ARM CPU, use the tag arm-cpu.
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Calculation for a robotic arm
good people! I was planning to design an arduino controlled robotic arm of DOF 5 for my 3rd year project. I wonder if anyone out there help me calculate everything (stress, strain, force, torque, arm ...
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Force Feedback Values on Robotic Gripper
I am trying to get force feedback data on a coupled linear motor which is used to grip objects as they are lifted off the ground by a robotic arm. However, my issue is that my value for the force used ...
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Arduino robotic arm kit
I want to buy a cheap robot arm for control it with an Arduino. Do you know of a kit that has a good value for money? I don't care about the degrees of freedom it has (4, 5 or 6), and above all I'm ...
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I need help getting the DH parameters for a humanoid robotic arm with four revolute joint. Kindly ignore point Q4 in the image below
I'm new into robotics, and I've been trying to get the DH parameters of the robotic arm in the image below.
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hitbot Robot Z-Arm 922. Does anybody know hot to use the safety stop programmaticaly?
I'm currently programming a sequence in which the robot go and picks two plastic parts from a mold and places them y different positions in order to cut the surplus plastic from the molding process, I ...
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Calculate joint torques in 3 joint RRR mechanism
I don't know if I could upload these things here, but I want solve the following exercise:.
I undestand that I should use the following formula:
But, I have to solve every joint torque, so how could ...
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When assigning frames in Denavit-Hartenberg (DH) parameters, where do I put the frame on end effector?
I have a simple question, for the last link (end effector) I need to estimate the parameters but when I put the reference frames in the center of the end effector, I just don't know.
Last link (end ...
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Marker pose flickering one axis from -4 to +18 when camera is not moving
I'm taking a sequence of frames from intel real sense and detecting april tags, I noticed the axis is flickering even camera is not moving. euler angle y axis is changing(visually and numerically) ...
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SCARA robot configuration subtype (first axis vertical)
I'm working on a project where I need a SCARA where the first axis is the linear / vertical one (as often seen in hobbyist configurations). Something like this:
https://www.igus.eu/product/21104?C=DE&...
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Light weight one axis hinge name/recommendation
I'm attempting to build a crow that can stay upright even when its perch tilts. For that I need to have some single axis hinges (not u-joints). I'm using 3mm rod for my internal supports and am ...
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Differential Inverse Kinematic Controller ROS
Inverse differential Kinematic - Problem with Orientation
Hey guys,
currently I am working to control my UR-Robot. My goal is to control the robot with inverse differential kinematics :
1.) vel_q = J^...
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Powering 3 MG996R servos
I'm building a robotic arm with 3 MG996R servos using Arduino Uno R3 board. I'm using this 16 channel servo motor driver for the project. I'd like to use an AC-DC adapter to power the servos. Is that ...
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Question about Impedance control in The Modern Robotics: Mechanisms, Planning, and Control
Impedance equation In 11.7.1 section $\tau = J^T(\theta)(\hat{\Lambda}(\theta)\ddot{x}+\hat{\eta}(\theta,\dot{x}) - (M\ddot{x}+B\dot{x} + Kx))$ is actually means $\tau = J^T(\theta)(\hat{\Lambda}(\...
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Impedance control algorithm in The Modern Robotics: Mechanisms, Planning, and Control
I am studying The Modern Robotics: Mechanisms, Planning, and Control (by Kevin Lynch, Frank Park and Evan Suma). I am trying to implement Chapter 11.7.1 Impedance-Control Algorithm of the book with ...
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Convert 5-axis CNC motion to robotic arm motion
I have G-code generated for a 5 axis CNC machine, with a rotating and tilting table. I would like to run this code on my robotic arm and therefore thought about converting it to a rotating and tilting ...
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Grasp matrix implementation
I've majorly followed Dex-net implementation to calculate a grasp matrix (G) to compute other grasp quality metrics (e.g., Ferrari Canny L1 metric or smallest singular value of G).
Based on my ...
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Why the robot is not at the zero configuration
As part of my testing, I was using Kuka's arm to test some kinematic controllers. In the picture below, when the arm is spawned in Gazebo, the positions of the joints are zero (i.e. obtained from <...
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For robot manipulators what is the relationship between angular velocity and time derivative of quaternions?
For a robot manipulator with joint angles $\theta$, the well-known relationship is
$$\omega = J_\omega(\theta)\dot{\theta}.$$
What if the angular velocity is represented as the time derivative of ...
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robotic arm controlled by mouse
I want to create a webot simulation for robotic arm. The entire arm should be controlled by the mouse. Is it possible to implement in webots?
I am trying simulation for this https://youtu.be/...
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Trajectory generation for robotic manipulator using trapezoidal velocity profile in MATLAB
I am trying to write code in MATLAB to generate a trajectory for a scara manipulator in the robot operational space with trapezoidal velocity profile for each segment passing through 5 waypoints using ...
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Meaning of p(q) in the expression for minimum clearance from obstacle for redundant robotic manipulators
Can somebody who has studied Industrial manipulators or has worked on Industrial manipulators using Jacobian Inverse and Jacobian Pseudo inverse algorithm for Inverse Kinematics please explain what ...
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Having trouble assigning x-axis to calcualte DH table
I'm trying to do a DH table but I'm having trouble determining thedirection of the x-axis in the following figure.
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Recommendations for a robot for scanning in a 2D plane
I'm new to robots and struggling to find information (buy) and sources on what we're looking for (or what we are trying to accomplish) for an idea (proof of concept) we want to test. We really don't ...
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What type of actuators are needed for a high accuracy, low load weight robotic arm?
I am trying to build a robotic arm that needs to lift a very low amount of weight (between 0.01-0.05kg) at a time, but it needs to be very precise (+/- 1mm accuracy ideally). The robot really only ...
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Can MoveIT framework be used separately from ROS, i.e. "as a standalone library"?
As far as I understand, MoveIT can act as a IK/FK solver one can supply input into (i.e. end-effector xyz) and get an output (joint angle values).
I'd like to utilize this aspect of MoveIT (version 1) ...
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Articulated Body Algorithm with gear ratio
I am reading up on the proposed articulated body algorithm by Featherstone, which goes like:
Pass 1:
\begin{equation}
\nu_0 = 0\\
\nu_i = {^i}X_{\lambda(i)}\nu_{\lambda(i)}+s_i\dot{q}_i\\
c_i = \nu_i \...
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Trajectory tracking for a robotic arm
I want a robotic arm to do trajectory tracking in the joint space. Suppose the waypoints are
$$
[t(0),q_1(0),q_2(0),q_3(0)],\\
\cdots,\\
[t(n-1),q_1(n-1),q_2(n-1),q_3(n-1)]
$$
I already know that I ...
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What Properties of a Robot Arm Would Make its C-Space a Genus-2 Torus?
Once upon a time, I saw a webpage that had a complete list (with ellipses, of course) of robot arms that have each surface (closed [compact and without boundary], 2-dimensional manifolds) as their c-...
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What could be the unit ( dimension) of the vectors spanning the Jacobian matrix?
Let the general forward rate kinematics equation for a serial mechanism be given as follows:
$$ \begin{bmatrix} \boldsymbol{v} \\ \boldsymbol{\omega} \end{bmatrix} = \begin{bmatrix} \boldsymbol{J}...
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How DH-parameters is obtained for this manipulator?
So I'm trying to find DH parameters for the manipulator as shown in this picture:
I draw coordinate systems for each joint as:
And I got this DH parameters:
Is this solution correct? Am I missing ...
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definition of self motion
From my understanding, self motion refers to a set of joint velocities which doesn't cause any cartesian motion on the end-effector. Here, by motion it is meant both linear and angular components or ...
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angle rates wrt another frame
My manipulator has a gyroscope attached to its end-effector (ee). The sensor provides angular velocity in the form of angular rates. Those rates are wrt fixed axis, so they effectively represent roll-...
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cartesian velocity control loop implementation
I'm using ROS (noetic) to intuitively control a franka manipulator using the panda_robot package for the simulation.
I've set up an extended kalman filter which fuses the following measures:
IMU data:...
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How to Implement a Physically Human-Controlled Robotic Arm?
I'm a complete beginner in robotics other than FIRST competitions at my school. I wanted to make a robotic arm that works by a person physically moving the end-effector in 3D space and the robot ...
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How to control end-effector orientation with vector part of quaternion?
I was reading this paper: Closed-Loop Manipulator Control Using Quaternion
Feedback, and it mentioned that you could control the end-effector orientation using a resolved rate controller where the ...
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Record and playback stepservo backdrive
I have a stepservo motor with a high precision encoder. I'd like to use it in "teach" mode where I can move it around with my hand (backdriving), and then playback whatever motion I did.
...
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How to choose the correct power switch ratings for robotics?
I am making a hexapod with MG996R servos and according to the specifications, each servo has a running current of 500 - 900 mA and a stall current of 2.5 A at 6 V. Since I am making a 3DOF hexapod, ...
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What formats are used to describe trajectories in robot simulator programs?
I am working for a university on a general tool for improving trajectories/cycles in robotic cells. As it should be general and not company/simulator-specific, I am trying to find common information ...
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No mutually perpendicular line between z-axes, are there still valid D-H Parameters?
I am trying to set up a generalized approach to generate DH parameters for my simulated robot arms, but I am having trouble setting up the frames. To find the X axis of each joint I read that I have ...
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How to go about programming Robot Arm with 3D point
I have a 6 DOF robot arm that I am programming. I want to be able to move the arm's claw to a 3D point in space. In order to do that, it needs to know the best combination of movements that will take ...
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what does free or forced torque mean in robot arm dynamics?
I'm trying to understand the dynamics (torque , velocity, etc ) of how a simple 2 DoF robotic arm rotates.
I am using the RoboAnalyzer simulator 1 .
It has a Inverse Dynamics setting of "Free&...
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What is the format and required content to define a Joint trajectory using the RoboAnalyzer simulator?
I'm trying to learn how to use the Roboanalyzer simulation tool to model and then display the torques required to pivot a 2 DoF arm. ( [http://www.roboanalyzer.com/][1] )
I see that the tool has a ...
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What is the meaning of joint space and configuration space and task space?
I'm reading an article about teleoperation systems and it talks about three spaces that include joint space, configuration space and task space frames. I do not know what these are, can you explain?
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Vision programming with OpenCV
I am currently working on a project on NiryoOne which requires facial detection of a person through NiryoOne camera (ELP SONY IMX). The code that I am using works on my laptop running ubuntu. However, ...
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Analytical solution to inverse kinematics of 5 dof robot arm
the followings are the equations I worked out for the inverse kinematics of a 5 dofs robotic arm.
First of all, the kinematic diagram:
For the joint angles $q_{2}, q_{3}$ and $q_{4}$ I resorted to ...
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Val3: Reading an Excel spreadsheet
I want to create a pPoint in Val3, which creates an array with the coordinates. The coordinates to be approached are in an Excel table. Is it possible to read this table using a command with Val3 and ...
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Mounting the ur5e robotic arm on a table
I am working on testing motion planning algorithms on a robotic arm. My arm collides with the ground while moving it from one point to another point. My solution to this problem is to mount the arm on ...
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6-DOF Robotic manipulator
I have the following question, I tried to solve it as follows, can anyone help solve the rest or guide me.
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Drawing in gazebo ROS
I am trying to simulate motion for a ur5e robotic arm. I am using the concept of Rodrigues rotation to get the orientation for the end effector. Is there any way to draw a line in gazebo or RViz from ...
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Multiple Stepper Synchronization with updating position control at specified speed
So I have build a 6-axis manipulator having all the degree of freedom. Currently I have used TeensyStep library for controlling synchronization of 6 stepper axis. Also I have tried AccelStepper ...
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