I have the following problem that i can't sort out, any ideas? the main problem is multiplying a 1D vector of two elements by 1D vector of two elements but here are the details.
i'm designing a controller and i want to make the controller work with a simulation model and by a switch make it work with the physical system. I'll implement this later as it's not on the picture. so i decided i'll put the controller separetely in a while loop and the system model in a simulation loop and synch. the timing.
my controller should be able to track a reference input signal vector (two inputs)- the step in the first picture. using a tracking technique in Franklin and Powell, fifth edition p.380, i've the following equation to implement. u= -k*x+k*N_x*R+N_u*R
where u: is the manipulated input vector - input to the simulated/physical system
x: is the state vector
k: is the state space gain matrix
N_u, N_x are vectors used for tracking the reference input.
R: the step input signal (vector) see 3rd picture
now my simple problem is ... whenever i want to multiply N_u*R ... i get an error of trying to multiply something of dimension 2 by something of dimension 1.
the thing is Nu is a 1D vector of two elements, R: is also a 1D vector of two elements. i guess that the problem could be solved if there is something to rotate a 1D vector or is it really another problem??
also, you might ask, why didn't i use the gain element on the simulation toolkit... because that only fits in a simulation loop, not a while loop which will not not help me put the controller separetly in a while loop. so that's why i'm using AxB.VI and I also tried the dot product VI. the thing is ... it says that the dimension of the demand signal is 1 and the dimension of Nu is 2 as in picture2 but as i defined the demand - see picture 3, it's a vector of two elements and i've an indicator showing Nu and it's also a vector of two elements.
any idea's .... very confused... or probably another way of implementing this part???
Message Edited by Jzee on 04-03-2007 12:58 PM
