References to the MPC Example

Hi!
I am looking for a reference for the included [MPC example](https://github.com/robotology/osqp-eigen/blob/master/example/src/MPCExample.cpp)

@GiulioRomualdi any hints on the system that corresponds to the that example?

Thanks.

Start with example/src/MPCExample.cpp to identify the system and assumptions used by the MPC example. Search the repository context and history for a source describing that system; done means providing a verified reference and explaining how it corresponds to the example.

Written by the indexing model from the issue text.