Periodic solutions of discontinuous second order differential equations. The porpoising effect Fonda, Alessandro Torres Villarroya, Pedro José Discontinuous systems Periodic boundary value problem Poincaré–Birkhoff theorem We construct a mathematical model in order to study the so called porpoising effect in racing cars, and prove that, when adding a small periodic perturbation, large-amplitude subharmonic solutions may arise 2023-10-13T12:02:34Z 2023-10-13T12:02:34Z 2023-07-10 journal article A. Fonda and P.J. Torres. Periodic solutions of discontinuous second order differential equations. The porpoising effect. Nonlinear Analysis: Real World Applications 74 (2023) 103948[https://doi.org/10.1016/j.nonrwa.2023.103948] https://hdl.handle.net/10481/84972 10.1016/j.nonrwa.2023.103948 eng http://creativecommons.org/licenses/by-nc-nd/4.0/ open access Attribution-NonCommercial-NoDerivatives 4.0 Internacional Elsevier