Constant-speed ramps for a central force field López Camino, Rafael Perdomo, Óscar Ramp Central force field Friction force TreadmillSled Partially supported by the grant no. MTM2017-89677-P, MINECO/AEI/FEDER, UE We investigate the problem of determining the planar curves that describe ramps where a particle of mass m moves with constant-speed when is subject to the action of the friction force and a force whose magnitude F(r) depends only on the distance r from the origin. In this paper we describe all the constant-speed ramps for the case F(r) = -m/r. We show the circles and the logarithmic spirals play an important role. Not only they are solutions but every other solution approaches either a circle or a logarithmic spiral. 2021-05-07T07:55:28Z 2021-05-07T07:55:28Z 2020-05-21 journal article Published version: Rafael López, Óscar Perdomo. Constant-speed ramps for a central force field. Discrete & Continuous Dynamical Systems, 2021, 41 (7) : 3447-3464. doi: [10.3934/dcds.2021003] http://hdl.handle.net/10481/68378 10.3934/dcds.2021003 eng http://creativecommons.org/licenses/by-nc-nd/3.0/es/ open access Atribución-NoComercial-SinDerivadas 3.0 España