Questions tagged [dh-parameters]

Denavit–Hartenberg parameters are the parameters associated with a particular convention for attaching reference frames to the links of spatial kinematic chains, or robot manipulators.

Denavit–Hartenberg parameters (also called DH parameters) are the four parameters associated with a particular convention for attaching reference frames to the links of a spatial kinematic chain, or robot manipulator:

$\theta_{i}$, $d_{i}$, $a_{i}$, $\alpha_{i}$

Homogeneous transformations can then be represented as the product of a series of these four basic transformations.

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DH parameters to solve forward kinematics problem

When solving the kinematics problem for a robot using DH parameters, if there are some passive joints between the actuator and the end effector, do I have to define the axis and transformations of passive joints too just like for active joints?
Haider
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Coordinate system of SCARA Manipulator

I am trying to understand how to draw coordinate system for forward kinematics. Figure is Could someone please explain how is the coordinate system drawn as per DH parameter? Basically when do we have to shift the origin of a frame and when not?…
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DH parameters solution for forward kinematics

I am stuck at a problem of solving DH parameters for a simple test mechanism. I know that the given mechanism is a structure but just for pure academic purposes assume that it's a real system. I only want to know the correct way to solve a system…
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Modified DH Parameters?

Is the notation of the geometry of robots from Khalil and Kleinfinger be considered as one of the probably "many" Modified DH Parameters?
Oswaldfig
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Modified DH Parameter for Puma 560

I'm trying to apply modified DH parameters (from Craig's version) to Puma 560. As per modified DH says, And the robot Puma 560 with axes and frame are, As per above sign convention, the sign of d2 and d3 should be negative. However, for the…
Nitin Kumar
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Homogenous Transformation Matrix for DH parameters

I'm studying Introduction to robotic and found there is different equations to determine the position and orientation for the end effector of a robot using DH parameters transformation matrix, they are : Example: Puma 560, All joints are…
Lama Sonmez
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Denavit Hartenberg parameters for 3R spatial manipulator - excercise

I'm learning about robotics and comparing two ways to calculate homogeneous transformation matrix. I'm comparing PoE (product of exponentials) and Denavit-Hartenberg parameters. For the same base frame and same position and orientation of the final…
Micik
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Denavit Hartenberg Exercises

I'm reading "Robot Modeling and Control" by Spong. It seems to me there are mistakes in the manual solutions provided by the authors. I came across the following two questions In this answer I think there is no $d_3$. It should be zero. In the…
CroCo
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DH parameters for offseted elbow joint

Below is the axis setup for the elbow joint manipulator. I am trying to workout the DH parameters for the manipulator. Green frame represents the base and frame1. Starting from there, I am able to get the correct values up to joint3 (purple frame).…
aron dada
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Between which joints does a given DH table row represent?

Say for example __ _____ | | ____ --------|_____|----------| |---------|____ |__| That ASCII art is supposed to represent a "rolling" revolute joint followed by a…
DeepDeadpool
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Modified DH Parameters for Puma 560 - Wrong Results

In continuation of my question on modified parameter for Puma 560 posted here Modified DH Parameters for Puma 560. Further I used a available dimension for Puma 560 here (FYI: the figure shows dimension in inches, but all following dimensions in DH…
Nitin Kumar
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Denavit Hartenberg parameters

Can anybody help figure out HD parameters for the case where two links with a revolute joint are in the same plane, thus that the variable angle is 0, but the twist is not 0. This is a simple drawing. I think that x-axis that is perpendicular to…
guest
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Solving for DH Parameters

Given three sets of joint angles in which the end effector is in the same position, is it possible to find the DH parameters? If the robot has 2 DOF in shoulder, 2 DOF in elbow, and 1 dof in wrist, with DH parameters as upper arm length, elbow…
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How this DH-parameters is obtained for this manipulator

Take a look at the following picture. I'm wondering how $\theta_3 -90^\circ$ appears in the table. As far as I see from the way axes arranged, it is only $\theta_3$.
CroCo
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Finding the DH parameters from Transformation Matrices

My questions is the following: How do I find the DH values of a given transformation matrix? Or a set of transformation matrices if one is not enough? I can assume that the angle theta is known for each of them and all other DH parameters are the…
Alex
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