Forward kinematics model using DH parameters in MATLAB

AI Thread Summary
The discussion focuses on implementing a forward kinematics model using Denavit-Hartenberg (DH) parameters in MATLAB for a robotic arm with five links. The user seeks guidance on how to input the DH parameters—theta, d, a, and alpha—into the transformation matrix to calculate the end-effector position. They provide a code snippet that defines a function to generate transformation matrices and another function to compute the overall transformation from the base to the end-effector. The main concern is correctly incorporating the joint angles (theta1 to theta5) into the transformation calculations. The thread emphasizes the importance of understanding matrix operations in this context for accurate kinematic modeling.
Joon
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Homework Statement
Derive the forward kinematics model in MATLAB using the DH parameters provided.
Relevant Equations
The homogeneous transformation matrix has the form shown in the attached image.
5 links (thus 6 frames) and corresponding theta, alpha, d and a values are all given.
However, I'm not sure how to start coding the DH parameters to derive a forward kinematics model.

I know that I'll have to use matrix operators, but do I just put in the values of the 4 factors mentioned above in the transformation matrix in the attached image and then calculate the transformation matrix from the origin to the end-effector?
Please help. Thanks.
 

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Below is my code. I have all the DH parameters that will allow me to calculate the end effector position.
I'm not sure where to input the values of thetas 1 ~5 shown at the bottom. Please help.

function [T] = getTransformMatrix(theta, d, a, alpha)
T = [cosd(theta) -sind(theta) * cosd(alpha) sind(theta) * sind(alpha) a * cosd(theta);...
sind(theta) cosd(theta) * cosd(alpha) -cosd(theta) * sind(alpha) a * sind(theta);...
0,sind(alpha),cosd(alpha),d;...
0,0,0,1];
end

function [T00,T01,T12,T23,T34,T45,EndEffector] = forwardKinematics(theta1, theta2, theta3, theta4, theta5)T00 = [1 0 0 0; 0 1 0 0; 0 0 1 0; 0 0 0 1];
T01 = getTransformMatrix(theta1,10.25,0,90);
T12 = getTransformMatrix(theta2,0,9,0);
T23 = getTransformMatrix(theta3,0,9,0);
T34 = getTransformMatrix(theta4,0,0,90);
T45 = getTransformMatrix(theta5,6.25,0,0);
EndEffector = T00 * T01 * T12 * T23 * T34 * T45;

end

theta1 = 30;
theta2 = 45;
theta3 = -90;
theta4 = 45;
theta5 = 60;
 
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