7.26.10

I was able to get the experiment running around 20Hz with Simulink by removing the pause between DM commands. This is great, except it now looks like DM dynamics are definitely screwing things up.

Here's a plot comparing the PSD's from 10000 frames using the same disturbance input and several different plant models.


Clearly using the original plant model in the AO loop, which contains a single delay and PI controller, produces crap; its worse than using just the classical controller. From my ARX experiments with the DM, I found that running at full speed seems to add an additional delay, and sure enough multiplying this ideal plant model with a delay works much better. Unsurprisingly the best results come with identifying a plant model first.

None of these results are as good as what I get with the artificial pause between DM commands, but the time difference is significant (20Hz vs. 4 Hz). I get the feeling this is a fact I'll just have to live with for the time being.