Triggered by technological advances, automated driving of vehicles is a reality. Actually driving vehicles, the use of integrated training devices that tell drivers what they should do, and GPS based look-ahead control strategies raise the question of what the optimal way of driving the vehicle would be. Optimality typically refers to energy consumption, time, driver's comfort, hardware wear-off, or a combination of these objectives.
Control problems that arise in this research field have at least two characteristics which stimulate development of novel mathematical methods. First, the real-time requirements are high as the time between measurements and a reaction of the controler is limited due to the possibly high driving speed. Second, models of interest involve discrete decisions, such as the optimal choice of gear or mode of operation in hybrid vehicles. Or switching behavior of traffic lights. Nonlinear Model Predictive Control problems in Automotive Engineering are hence in the class of MIOCP.
This YouTube video is an exemplary visualization of a time-optimal ride on the Hockenheim ring, by Florian Kehrle and Sebastian Sager. The solution has been calculated with modern mathematical methods. It is based on a simplified dynamical model, including nonlinear tire dynamics. The optimization took the gear choice explicitely into account. The solution is open loop without any feedback and for one complete round.
Selected publications
@incollection{Bethge2022, author = {Bethge, J. and Findeisen, R. and Le, D.D. and Merkert, M. and H., Rewald and Sager, S. and Savchenko, A. and Sorgatz, S.}, title = {Mathematical Optimization and Machine Learning for Efficient Urban Traffic}, booktitle = {KoMSO Success Stories on Mathematics in Industry}, publisher = {Springer}, year = {2022}, editor = {K\"{u}fer, Karl-Heinz and Maass, Peter and Milde, Anja and Schulz, Volker}, pages = {113--120}, url = {https://mathopt.de/publications/Bethge2020.pdf} }
@article{Le2022, author = {Le, D.D. and Merkert, M. and Sorgatz, S. and Hahn, M. and Sager, S.}, title = {Autonomous traffic at intersections: an optimization-based analysis of possible time, energy, and {CO2} savings}, journal = {Networks}, year = {2022}, volume = {79}, number = {3}, pages = {338--363}, url = {https://optimization-online.org/?p=16226}, doi = {10.1002/net.22078} }
@article{Robuschi2021, author = {Robuschi, N. and Zeile, C. and Sager, S. and Braghin, F.}, title = {Multiphase Mixed-Integer Nonlinear Optimal Control of Hybrid Electric Vehicles}, journal = {Automatica}, year = {2021}, volume = {123}, pages = {109325}, url = {https://optimization-online.org/?p=15819} }
@phdthesis{Sorgatz2016, author = {Sorgatz, S.}, title = {Optimization of Vehicular Traffic at Traffic-Light Controlled Intersections}, school = {Otto von Guericke University Magdeburg}, year = {2016}, url = {https://mathopt.de/publications/Sorgatz2016.pdf} }
@article{Sager2015, author = {Sager, S. and Claeys, M. and Messine, F.}, title = {{E}fficient upper and lower bounds for global mixed-integer optimal control}, journal = {{J}ournal of {G}lobal {O}ptimization}, year = {2015}, volume = {61}, number = {4}, pages = {721--743}, doi = {10.1007/s10898-014-0156-4} }
@incollection{Zanon2014, author = {Zanon, Mario and Frasch, JanickV. and Vukov, Milan and Sager, Sebastian and Diehl, Moritz}, title = {Model Predictive Control of Autonomous Vehicles}, booktitle = {Optimization and Optimal Control in Automotive Systems}, publisher = {Springer International Publishing}, year = {2014}, editor = {Waschl, Harald and Kolmanovsky, Ilya and Steinbuch, Maarten and del Re, Luigi}, volume = {455}, series = {Lecture Notes in Control and Information Sciences}, pages = {41--57}, doi = {10.1007/978-3-319-05371-4_3} }
@inproceedings{Frasch2013b, author = {Frasch, J. V. and Gray, A. J. and Zanon, M. and Ferreau, H. J. and Sager, S. and Borrelli, F. and Diehl, M.}, title = {{A}n {A}uto-generated {N}onlinear {MPC} {A}lgorithm for {R}eal-{T}ime {O}bstacle {A}voidance of {G}round {V}ehicles}, booktitle = {{P}roceedings of the {E}uropean {C}ontrol {C}onference}, year = {2013} }
@inproceedings{Kirches2013, author = {Kirches, C. and Bock, H.G. and Schl\"oder, J.P. and Sager, S.}, title = {{M}ixed-integer {NMPC} for predictive cruise control of heavy-duty trucks}, booktitle = {{E}uropean {C}ontrol {C}onference}, year = {2013}, pages = {4118--4123}, address = {Zurich, Switzerland} }
@inproceedings{Zanon2013b, author = {Zanon, M. and Frasch, J. and Diehl, M.}, title = {{N}onlinear {M}oving {H}orizon {E}stimation for {C}ombined {S}tate and {F}riction {C}oefficient {E}stimation in {A}utonomous {D}riving}, booktitle = {{P}roceedings of the {E}uropean {C}ontrol {C}onference}, year = {2013} }
@inproceedings{Frasch2012b, author = {Frasch, J. V. and Kraus, T. and Saeys, W. and Diehl, M.}, title = {{M}oving {H}orizon {O}bservation for {A}utonomous {O}peration of {A}gricultural {V}ehicles}, booktitle = {{P}roceedings of the {E}uropean {C}ontrol {C}onference ({ECC})}, year = {2012} }
@inproceedings{Gao2012, author = {Gao, Y. and Gray, A. and Frasch, J. V. and Lin, T. and Tseng, E. and Hedrick, J.K. and Borrelli, F.}, title = {{S}patial {P}redictive {C}ontrol for {A}gile {S}emi-{A}utonomous {G}round {V}ehicles}, booktitle = {{P}roceedings of the 11th {I}nternational {S}ymposium on {A}dvanced {V}ehicle {C}ontrol}, year = {2012} }
@inproceedings{Kehrle2011, author = {Kehrle, F. and Frasch, J.V. and Kirches, C. and Sager, S.}, title = {{O}ptimal control of {F}ormula 1 race cars in a {VDrift} based virtual environment}, booktitle = {{P}roceedings of the 18th {IFAC} {W}orld {C}ongress}, year = {2011}, editor = {Bittanti, S. and Cenedese, A. and Zampieri, S.}, pages = {11907--11912}, address = {Milan, Italy}, url = {https://mathopt.de/publications/Kehrle2011.pdf}, doi = {10.3182/20110828-6-IT-1002.02954} }
@mastersthesis{Buchner2010, author = {Buchner, A.}, title = {{A}uf {D}ynamischer {P}rogrammierung basierende nichtlineare modellpr\"adiktive {R}egelung f\"ur {LKW}}, school = {Ruprecht-Karls-Universit\"at Heidelberg}, year = {2010}, url = {https://mathopt.de/publications/Buchner2010.pdf} }
@patent{Gehring2010, author = {Gehring, O. and Kauffmann, F. and Bock, H.G. and Kirches, C. and Sager, S. and Schloeder, J.P.}, title = {Verfahren zum Steuern des Betriebs eines Fahrzeugs}, year = {2010}, number = {DE102009030784A1}, url = {https://patents.google.com/patent/DE102009030784A1} }
@article{Kirches2010, author = {Kirches, C. and Sager, S. and Bock, H.G. and Schl\"oder, J.P.}, title = {{T}ime-optimal control of automobile test drives with gear shifts}, journal = {{O}ptimal {C}ontrol {A}pplications and {M}ethods}, year = {2010}, volume = {31}, number = {2}, pages = {137--153}, url = {https://mathopt.de/publications/Kirches2010.pdf} }