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urosolia / RacingLMPC

Implementation of the Learning Model Predictive Controller for autonomous racing
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A possible error coding in LTVMPC.py #11

Open CeHao1 opened 4 years ago

CeHao1 commented 4 years ago

Hi Rosolia, I am Hao, now studying autonomous racing vehicle in UCB. Your LMPC is amazing while I found a possible error in the fnc/PathFollowingLTVMPC.py, line 279, where you linearize the epsi/ey. depsi_ey = - dt (vx np.cos(epsi) - vy * np.sin(epsi)) / (den*2) cur * (-cur) However, according to the kinetic model, which you write in the "Learning how to autonomously race a car: a predictive control approach" f1 I think this equation should be minus rather than positive based on fractional derivative. So I try to change this equation and finally found the simulator runs faster.(6.0s before, 5.8s after). I am not quite sure if there is a minor error, but I hope this comment can help you. In all, thank you for sharing the LMPC. If you don't mind, I want to implement the LMPC in my project in UCB.

urosolia commented 4 years ago

Hi,

It seems that in the LMPC file is implemented correctly (look here: https://github.com/urosolia/RacingLMPC/blob/devel-ugo/src/fnc/LMPC.py#L706). Did you modify just the LTVMPC.py or also the LMPC.py?

Sure, feel free to implement it. Let me know if you have questions

CeHao1 commented 4 years ago

It seems that the code you mentioned in LMPC is correct while that in the PathFollowingLTVMPC.py is different. https://github.com/urosolia/RacingLMPC/blob/6b83c3ffc0a73ad6ed4f999ca0a7802ca2416046/src/fnc/PathFollowingLTVMPC.py#L279 Thank you for your generosity. Ce Hao