SRMD Table Simulation

What is modeled:

* Approximate servovalve dynamics (see note below)
* Actuator dynamics
* Geometry effects
* Rigid body dynamics in six degrees of freedom
* Approximate physical displacement and velocity limits
* Accumulator bank pressure change with flow

What is not modeled:

* Individual poppets (see note below)
* Hydraulic distribution losses and dynamics
* Sensor and conditioner dynamics
* Foundation interaction
* Specimen, table, and bowstring resonances
* Friction
* Exact physical displacement and velocity limits
  (approximate physical limits values are precomputed relative
  to the table origin, yet applied at the center of gravity)
* Exact nonlinear behavior when hitting a physical limit or
  coming out of a physical limit.

Other notes:

* The individual poppets of each actuator are consolidated
  into a single virtual servovalve for modeling purposes.
* Each upper and lower single-ended outrigger pair is
  modeled as one double-ended actuator applied to a single
  point, the upper outrigger table attachment point.
