Multiplying matrices and vectors in loop

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This is the part of the code I want to solve but it gives me error, says that the matrix size are not the same but they are all 3 x 3. Do I need a for loop maybe? Can you help with it?
clear all, clc; H=1700 %height
dSG=0.129*H;
dH=0.185*H;
dF=0.146*H;
FiA = -10:20:170 ;
FiFm = -60:10:170 ;
FiRm=-60:20:90;
FiEF=-90:20:60;
COSA=cosd(FiA);
SINA=sind(FiA);
RA = arrayfun( @(sinFif, cosFif) [cosFif 0 sinFif; 0 1 0; -sinFif 0 cosFif], SINA, COSA, 'uniform', 0)
CA=cell2mat(RA)
COSE=cosd(FiEF);
SINE=sind(FiEF);
RE = arrayfun( @(sinFif, cosFif) [cosFif 0 sinFif; 0 1 0; -sinFif 0 cosFif], SINE, COSE, 'uniform', 0)
CE=cell2mat(RE)
[gFiA, gFiFm] = ndgrid(FiA, FiFm);%you want all combinations
gFiF = gFiFm + gFiA / 3 ;
COSF = cosd(gFiF); %cosd and sind because you are working in degrees !
SINF = sind(gFiF );
RF = arrayfun( @(sinFif, cosFif) [1 0 0; 0 cosFif -sinFif; 0 sinFif cosFif], SINF, COSF, 'uniform', 0)
CF=cell2mat(RF)
rSG=[-dSG 0 0]'; %shoulder joint - torso
rH=[0 0 -dH]' ;% upper arm
rF=[0 dF 0]';%fore arm
rW=rSG+CA*CF*rH+CE*rF

Accepted Answer

KL
KL on 14 Dec 2017
they are all 3 x 3...
No, they are not. Check the output for the following
size(CA)
size(CF)
and the other matrices you have.
Just copy-pasting the code doesn't help either. What exactly do you want to do?
  1 Comment
Tea Arrigoni
Tea Arrigoni on 14 Dec 2017
That is correct. Sorry for that. I am relatively new in Matlab. I will send you in the attachment what I need but in short I need to recreate all point that a human wrist can reach in workspace for an exoskeleton-rehabilitation device we are trying to build (My PhD). I have three angles in shoulder FiA, FiF and FiR, and I have one FiEF in elbow and in correlation of shoulder and elbow movement I want to get a cloud of points in a workspace. I have all formulas but I have to make the whole iteration i MatLab. I managed to compute point by point (just tested it) but I need it for the whole area. The formulas you can see attached. Can you help regarding this issue?

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