I want to use a matrix and a function to then create another function

Question

Michael Sposato 2022-11-28

0
链接

此问题的直接链接

https://ww2.mathworks.cn/matlabcentral/answers/1866023-i-want-to-use-a-matrix-and-a-function-to-then-create-another-function

评论： Stephen23 2022-11-29

I currently have a matrix that has known values that I then want to use to create a second matrix using a function loop. The matrix within the function loop has four variables that coincide with the variables from the above matrix DH. How do I use each row of the DH matrix to be a value to then insert into the Ai matrix? (Colum 1 = theta, Column 2 = d, etc.) I need this to then output 6 different matrices A1,A2,etc.

clear

clc

close all

theta1 = -50;

theta2 = 30;

theta3 = 15;

theta4 = -75;

theta5 = -45;

theta6 = -60;

DH = [theta1, 486.5, 150, -90;...

theta2+90, 0, -700, 0;...

theta3, 0, 0, 90;...

theta4, 600, 0, -90;...

theta5, 0, 0, 90;...

theta6, 65, 0, 0];

function Ai = getHomogeneousTransform(theta, d, a, alpha)

Ai = [cos(theata), -sin(theta)*cos(theta), sin(theta)*sin(alpha),a*cos(theta);...

sin(theta),cos(theta)*cos(alpha),-cos(theta)*sin(alpha),a*sin(theta);...

0, sin(alpha), cos(alpha), d;...

0,0,0,1];

end

1 个评论
显示 -1更早的评论隐藏 -1更早的评论

Stephen23 2022-11-29

"How do I use each row of the DH matrix to be a value to then insert into the Ai matrix?"

Use a loop and indexing.

"I need this to then output 6 different matrices A1,A2,etc."

Numbering variable names like that forces you into writing slow, complex, inefficient, buggy code. Best avoided.

The simple and very efficient approach is to use indexing. You should use indexing.

请先登录，再进行评论。

请先登录，再回答此问题。

Answer 1

Torsten 2022-11-28

0
链接

此回答的直接链接

https://ww2.mathworks.cn/matlabcentral/answers/1866023-i-want-to-use-a-matrix-and-a-function-to-then-create-another-function#answer_1114673

在 MATLAB Online 中打开

theta1 = -50;
theta2 = 30;
theta3 = 15;
theta4 = -75;
theta5 = -45;
theta6 = -60;
DH  = [theta1, 486.5, 150, -90;...
    theta2+90, 0, -700, 0;...
    theta3, 0, 0, 90;...
    theta4, 600, 0, -90;...
    theta5, 0, 0, 90;...
    theta6, 65, 0, 0];
A = cell(size(DH,1),1);
for i = 1:size(DH,1)
  A{i} = getHomogeneousTransform(DH(i,1)*pi/180, DH(i,2), DH(i,3), DH(i,4)*pi/180);
  A{i}
end
ans = 4×4
    0.6428    0.4924    0.7660   96.4181
   -0.7660    0.0000    0.6428 -114.9067
         0   -1.0000    0.0000  486.5000
         0         0         0    1.0000
ans = 4×4
   -0.5000    0.4330         0  350.0000
    0.8660   -0.5000         0 -606.2178
         0         0    1.0000         0
         0         0         0    1.0000
ans = 4×4
    0.9659   -0.2500    0.2588         0
    0.2588    0.0000   -0.9659         0
         0    1.0000    0.0000         0
         0         0         0    1.0000
ans = 4×4
    0.2588    0.2500    0.9659         0
   -0.9659    0.0000    0.2588         0
         0   -1.0000    0.0000  600.0000
         0         0         0    1.0000
ans = 4×4
    0.7071    0.5000   -0.7071         0
   -0.7071    0.0000   -0.7071         0
         0    1.0000    0.0000         0
         0         0         0    1.0000
ans = 4×4
    0.5000    0.4330         0         0
   -0.8660    0.5000         0         0
         0         0    1.0000   65.0000
         0         0         0    1.0000
function Ai = getHomogeneousTransform(theta, d, a, alpha)
 Ai = [cos(theta),-sin(theta)*cos(theta),sin(theta)*sin(alpha),a*cos(theta);...
       sin(theta),cos(theta)*cos(alpha),-cos(theta)*sin(alpha),a*sin(theta);...
       0,sin(alpha),cos(alpha),d;...
       0,0,0,1];
end