I am getting an error "Index in position 1 exceeds array bounds. Index must not exceed 1." Error in "v_x(n) = fmincon(fun_x(n), x0, A_x(n,:), b_x(n,:)); Can someone help"

Here is the code:

t_span = 30;
dt = 0.01;
t = 0:dt:t_span;
x(1) = 0; %Initial condition for state x
y(1) = 0; %Initial condition for state y
x0 = [0]; %initial condition for v_x in fmincon
y0 = [0]; %initial condition for v_y in fmincon 
goal = [3; 5]; %final trajectory coordinate
obs_1_center = [1; 2]; %obstacle coordinate
D_obs = 0.5; %some positive value
R = 0.5; %radius of the obstacle
K = 1; %controller gain
alpha = 0.5; %constant
for n = 1:length(t)
    obs_1_x(n) = obs_1_center(1) + R*cos(0.01*n);
    obs_1_y(n) = obs_1_center(2) + R*sin(0.01*n);
    
    v_des_x(n) = - K * (x(n) - goal(1));
    v_des_y(n) = - K * (y(n) - goal(2));
    A_x(n) = - (x(n) - obs_1_x(n)) / norm (x(n) - obs_1_x(n)) ;
    A_y(n) = - (y(n) - obs_1_y(n)) / norm (y(n) - obs_1_y(n)) ;
    
    b_x(n) = alpha * ( norm(x(n) - obs_1_x(n)) - D_obs );
    b_y(n) = alpha * ( norm(y(n) - obs_1_y(n)) - D_obs );
    fun_x{n} = @(v_x)((norm(v_x(n) - v_des_x(n)))^2); 
    fun_y{n} = @(v_y)((norm(v_y(n) - v_des_y(n)))^2);
    v_x(n) = fmincon(fun_x(n), x0, A_x(n,:), b_x(n,:));
    v_y(n) = fmincon(fun_y(n), y0, A_y(n,:), b_y(n,:));
    x(n+1) = x(n) + dt * (v_x(n));
    y(n+1) = y(n) + dt * (v_y(n));
end

Answer 1

[Jan]

Change:

    fun_x{n} = @(v_x)((norm(v_x(n) - v_des_x(n)))^2);
    fun_y{n} = @(v_y)((norm(v_y(n) - v_des_y(n)))^2);
    v_x(n) = fmincon(fun_x(n), x0, A_x(n,:), b_x(n,:));
    v_y(n) = fmincon(fun_y(n), y0, A_y(n,:), b_y(n,:));    

to:

    fun_x{n} = @(v_x)((norm(v_x - v_des_x(n)))^2); 
    fun_y{n} = @(v_y)((norm(v_y - v_des_y(n)))^2);
    v_x(n) = fmincon(fun_x{n}, x0, A_x(n), b_x(n));
    v_y(n) = fmincon(fun_y{n}, y0, A_y(n), b_y(n));   

In this definition:

    @(v_x)((norm(v_x(n) - v_des_x(n)))^2)    

the inout argument v_x is a scalar. Then v_x(n) must fail for n > 1.

A_x(n) = ... creates a row vector, but A_x(n,:) requests the n.th row. A(n) uses the n.th element instead.

[Pallov Anand]

It worked....Thanks a lot :)