Error using * Incorrect dimensions for matrix multiplication
3 views (last 30 days)
Show older comments
How can I fix
Error using *
Incorrect dimensions for matrix multiplication. Check that the
number of columns in the first matrix matches the number of rows in
the second matrix. To perform elementwise multiplication, use '.*'.
Error in Untitled (line 55)
s23 = -((a3+a2*c3)*Pz)+(c1*Px+s1*Py)*(a2*s3-d4);
?
Here is the code
% *** Program ik_Algebraic.m
...Solving inverse kinematics...
...Created on March 2021 by KKK.Adams.***
%%
clear ; close all; clc;
% Link lenghts & Offsets in Millimeters(mm)
a2=380; a3=0; d3=0; d4=351; L5=89;
% Finding Px, Py, Px
p1x= 202.90; p1y= 55.85; p1z =-449.09;
p2x= 232.91; p2y= 49.08; p2z =-465.79;
p3x= 199.39; p3y= 31.37; p3z =-445.48;
p4x= 196.96; p4y= 55.17; p4z =-459.50;
Mx= 250.32; My= 44.14; Mz= -395.82;
p1_p2= 35; p1_p3= 25; p1_p4= 12;
nx = (p2x-p1x)/p1_p2; ny= (p2y-p1y)/p1_p2;nz= (p2z-p1z)/p1_p2;
disp('nx = '),disp(nx)
disp('ny = '),disp(ny)
disp('nz = '),disp(nz)
sx = (p3x-p1x)/p1_p3; sy= (p3y-p1y)/p1_p3;sz= (p3z-p1z)/p1_p3;
disp('sx = '),disp(sx)
disp('sy = '),disp(sy)
disp('sz = '),disp(sz)
ax = (p4x-p1x)/p1_p4; ay= (p4y-p1y)/p1_p4;az= (p4z-p1z)/p1_p4;
disp('ax = '),disp(ax)
disp('ay = '),disp(ay)
disp('az = '),disp(az)
%
Pxfp= 206.2437; Pyfp= 39.0914; Pzfp= -472.9750; %from forward kinematics
Px = (Pxfp-L5*ax); Py = (Pyfp-L5*ay); Pz = (Pzfp-L5*az);
% Finding joint angle 1
theta1 = atan2(Py,Px)-atan2(d3,[1 -1]*sqrt(Px^2+Py^2-d3^2)); % +/-...[1 -1]
theta1 = rad2deg(theta1);
disp('theta1 ='),disp(theta1)
%
c1 = cos(theta1);
s1 = sin(theta1);
% Finding joint angle 3
K = (Px^2+Py^2+Pz^2-a2^2-a3^2-d3^2-d4^2)/(2*a2);
disp('K= '),disp(K)
%
theta3 = atan2(a3,d4)-atan2(K,[1 -1]*sqrt(a3^2+d4^2-K^2)); % +/-...[1 -1]
theta3 = rad2deg(theta3);
disp('theta3 ='),disp(theta3)
%
c3 = cos(theta3);
s3 = sin(theta3);
% Finding joint angle 2
s23 = -((a3+a2*(c3))*Pz)+((c1)*Px+s1*Py)*(a2*(s3-d4));
c23 = (-d4+a2*s3)*Pz+(c1*Px+s1*Py)*(a2*c3+a3);
theta23 = atan2(s23,c23);
theta23 = rad2deg(theta23);
theta2 = theta23 - theta3;
disp('theta2 ='),disp(theta2)
0 Comments
Accepted Answer
DGM
on 29 Mar 2021
c1,c3,s1,s3 are vectors. If you want elementwise multiplication, use that.
s23 = -((a3+a2*c3)*Pz) + (c1*Px+s1*Py).*(a2*(s3-d4));
c23 = (-d4+a2*s3)*Pz + (c1*Px+s1*Py).*(a2*c3+a3);
Don't know if that's the intention.
More Answers (0)
See Also
Categories
Find more on Assembly in Help Center and File Exchange
Community Treasure Hunt
Find the treasures in MATLAB Central and discover how the community can help you!
Start Hunting!