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alexliniger / MPCC

Model Predictive Contouring Controller (MPCC) for Autonomous Racing
Apache License 2.0
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What is ZHO? #88

Closed ziyi-joe closed 1 year ago

ziyi-joe commented 1 year ago

Hi! Thank u so much for the perfect work! I have a question about the ZHO you mention in the model.cc https://github.com/alexliniger/MPCC/blob/bd331621ba47ae3326711922a863bdb1cdf2d2ea/C%2B%2B/Model/model.cpp#L282 Do you mean ZOH(Zero-Order Hold)? BTW, I have never seen the integrator in the discretizeModel. It i concise and precise. Could you give some reference? I'd like to learn about it, but I didn't find it on Google.

alexliniger commented 1 year ago

Yes it is zero order hold, and what I use is the matrix exponential. The matrix exponential is the exact discretization of the linear system, for nonlinear system it is not exact. However, it is definitly more accurate than euler forward. In the new automatic diff branch I am using RK4 for all discretizations.