RT Journal Article T1 An elementary approach based on variational inequalities for modeling a friction-based locomotion problem A1 Chen, Panyu A1 Mateos González, Álvaro A1 Mertz, Laurent AB We propose an elementary proof based on a penalization technique to show the existence and uniqueness of the solution to a system of variational inequalities modeling the friction-based motion of a two-body crawling system. Here for each body, the static and dynamic friction coefficients are equal. PB Elsevier SN 0893-9659 YR 2025 FD 2025-02 LK https://hdl.handle.net/20.500.14352/119345 UL https://hdl.handle.net/20.500.14352/119345 LA eng NO Chen, P., Mateos González, Á., & Mertz, L. (2025). An elementary approach based on variational inequalities for modeling a friction-based locomotion problem. Applied Mathematics Letters, 160. https://doi.org/10.1016/J.AML.2024.109305 NO L.M. is thankful for support through NSFC Grant No. 12271364 and GRF Grant No. 11302823. We thank the anonymous referee for important feedback. NO National Nature Science Foundation (China) DS Docta Complutense RD 19 ene 2026