Haven't had much luck getting the spgd controller to work with just the maximum image intensity. The problem is that it simply searches around without actually maximizing anything. In desperation I went back and tried running it with a constant command across all actuators, essentially optimizing over a scalar value.
Since the optimization variable is a scalar in this case we can look at the objective function graphically. Here's a plot of the maximum intensity vs. the constant command. Clearly its not concave, although it would be quasi if it wern't for that little bit beyond the max. There's an obvious maximum, but the problem lies in the flat area from 0 to ~180. When the gradient descent algorithm is in this region there is no obvious direction of steepest descent with small perturbations, so the algorithm gets stuck at the intial value.
Its clear from the images themselves that the beam tightens as the maximum command is approached, but the peak intensity doesn't necessarily increase measurably. I'm trying now to come up with another objecive function that measures the spread of the beam based on a "moment of inertia" calculated from the image.
The results today weren't great, but I was using the center of the frame as the origin for the inertia calculation rather than the "center of mass." I'll try changing this tomorrow, maybe by using the parallel axis theorem to save computational time.
I got around 50% on my final. About average. Along with Adaptive Filtering and Linear Programming, that class should establish my minor field in EE, so I'm technically finished with classes forever.
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