Quoting Doug Ausmus <daus...@gmail.com>:

Have you calculated the sampling/control intervals yet? If so, what are the fastest ones or most critical ones that must absolutely be deterministic?

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`No, but we have them bounded. There is no need to run the control loop`

`faster than 1000Hz (which is a 25-50Hz *control* bandwidth) as we`

`proved when considering actuator force would destroy the fins, yet I`

`think I can easily make the case that it must be faster than 10Hz`

`(which is a 0.25-0.50Hz *control* bandwidth) due to the fast roll axis`

`dynamics.`

`So, between 10 and 1000 loops per second. If I had to pick today, I'd`

`say 400Hz.`

`In that time, we need to be able to perform several 12x12 matrix`

`multiplies, a few martix-vector multiplies, matrix add and subtract`

`operations, and one or two 12x12 inversions (this is pretty typical of`

`an optimal control scheme).`

`btw, '25Hz *control* bandwidth' means the rocket will follow a 25Hz`

`sine wave 'point in this direction' command of +- 10 degree amplitude`

`with at least +- 7 degree response and less than 90 degrees of phase`

`lag.`

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