The dimensions of the array are different, but I don't know which part is wrong.

Hi, i have 1 problem as follow:

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>> Example1_T_Matrix1

Error using horzcat

Dimensions of arrays being concatenated are not consistent.

Error in Example1_T_Matrix1 (line 30)

T01 = [R_z_1 P_0;0 0 0 1];

================================================================================================

P_0 = [0 0 0]; % 0벡터

P_1 = [0 0.1 0.2]; % 1번 프레임에서 Linkage 길이

P_2 = [0 -0.1 0.6]; % 2번 프레임에서 Linkage 길이

P_3 = [0 0.2 0.6]; % 3번 프레임에서 Linkage 길이

P_4 = [0 0.1 0.1]; % 4번 프레임에서 Linkage 길이

theta_1 = 0/180*pi; % 1축 회전각

theta_2 = 0/180*pi; % 2축 회전각

theta_3 = 0/180*pi; % 3축 회전각

theta_4 = 0/180*pi; % 4축 회전각

% R_x = [1 0 0; 0 cos(theta) -sin(theta); 0 sin(theta) cos(theta)];

% R_y = [cos(theta) 0 sin(theta); 0 1 0; -sin(theta) cos(theta)];

% R_z = [cos(theta -sin(theta) 0; sin(theta) cos(theta) 0; 0 0 1];

R_z_1 = [cos(theta_1) -sin(theta_1) 0;

sin(theta_1) cos(theta_1) 0;

0 0 1]; % Frame 1 z축 회전

R_x_2 = [1 0 0;

0 cos(theta_2) -sin(theta_2);

0 sin(theta_2) cos(theta_2)]; % Frame 2 x축 회전

R_x_3 = [1 0 0;

0 cos(theta_3) -sin(theta_3);

0 sin(theta_3) cos(theta_3)]; % Frame 3 x축 회전

R_y_4 = [cos(theta_4) 0 sin(theta_4);

0 1 0;

-sin(theta_4) 0 cos(theta_4)]; % Frame 4 y축 회전

% T행렬 작성

T01 = [R_z_1 P_0;0 0 0 1];

T12 = [R_x_2 P_1;0 0 0 1];

T23 = [R_x_3 P_2;0 0 0 1];

T34 = [R_y_4 P_3;0 0 0 1];

% T행렬 합성

T02 = T01*T12; % 0 Frame에서 본 2 Frame

T03 = T01*T12*T23; % 0 Frame에서 본 3 Frame

T04 = T01*T12*T23*T34; % 0 Frame에서 본 4 Frame

% Global 좌표계(0 Frame)에서 본 각 Frame 별 링키지

P_1_G = T01*[P_1;1];

P_2_G = T02*[P_2;1];

P_3_G = T03*[P_3;1];

P_4_G = T04*[P_4;1];

% 링키지 표시(선분의 경우 시점과 종점 좌표가 필요)

L1 = [P_0 P_1_G(1:3,1)];

L2 = [P_1_G(1:3,1) P_2_G(1:3,1)];

L3 = [P_2_G(1:3,1) P_3_G(1:3,1)];

L4 = [P_3_G(1:3,1) P_4_G(1:3,1)];

% 좌표계 표시(x, y, z좌표의 시점과 종점, 크기는 0.1)

x_L = [0 0.1;0 0;0 0;1 1];

y_L = [0 0;0 0.1;0 0;1 1];

z_L = [0 0;0 0;0 0.1;1 1];

% Global 좌표계에서 본 각 좌표계

x_1 = T01*x_L;

y_1 = T01*y_L;

z_1 = T01*z_L;

x_2 = T02*x_L;

y_2 = T02*y_L;

z_2 = T02*z_L;

x_3 = T03*x_L;

y_3 = T03*y_L;

z_3 = T03*z_L;

x_4 = T04*x_L;

y_4 = T04*y_L;

z_4 = T04*z_L;

close all

figure(1)

% Frame plot

plot3(x_1(1,:), x_1(2,:),x_1(3,:),'r', x_2(1,:),x_2(2,:),x_2(3,:),'r',...

x_3(1,:),x_3(2,:),x_3(3,:),'r', x_4(1,:),x_4(2,:),x_4(3,:),'r', 'LineWidth',1)

% 여러개를 하나의 figure 위에 그리기 위해

hold on

plot3(y_1(1,:), y_1(2,:),y_1(3,:),'g', y_2(1,:),y_2(2,:),y_2(3,:),'g',...

y_3(1,:),y_3(2,:),y_3(3,:),'g', y_4(1,:),y_4(2,:),y_4(3,:),'g', 'LineWidth',1)

plot3(z_1(1,:), z_1(2,:),z_1(3,:),'b', z_2(1,:),z_2(2,:),z_2(3,:),'b',...

z_3(1,:),z_3(2,:),z_3(3,:),'b', z_4(1,:),z_4(2,:),z_4(3,:),'b', 'LineWidth',1)

plot3(L1(1,:),L1(2,:),L1(3,:),'-o','color',[0, 0.4470, 0.7410],'LineWidth',2)

plot3(L2(1,:),L2(2,:),L2(3,:),'-o','color',[0.8500, 0.3250, 0.0980],'LineWidth',2)

plot3(L3(1,:),L3(2,:),L3(3,:),'-o','color',[0.9290, 0.6940, 0.1250],'LineWidth',2)

plot3(L4(1,:),L4(2,:),L4(3,:),'-o','color',[0.4940, 0.1840, 0.5560],'LineWidth',2)

grid on

axis equal

tilte('robot')

figure(2)

Answer 1

[Prateek Rai]

To my understanding, you are getting an array because dimensions of arrays being concatenated are not consistent.

The error is proabably arrising on line 30 i.e.,

T01 = [R_z_1 P_0;0 0 0 1];

Here, size of R_z_1 is [3, 3] , Size of P_0 is [1, 3].

To concatenate two matrices, they must have compatible sizes. In other words, when you concatenate matrices horizontally, they must have the same number of rows.

Thus,

[R_z_1 P_0]

Here, number of rows is not same thus they are not compatible and hence it is throwing error. Now since,

[R_z_1 P_0] 

is not compatible, thus,

 [R_z_1 P_0;0 0 0 1] 

is also not compatible.

You can refer to following answer to find more on a possible workaround. You can also refer to Creating, Concatenating, and Expanding Matrices MathWorks documentation page to find more information on concatenation in general.