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arXiv · 1610.03461

On break-away forces in actuated motion systems with nonlinear friction

Michael Ruderman
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Abstract

The phenomenon of so-called break-away forces, as maximal actuation forces at which a sticking system begins to slide and thus passes over to a steady (macro) motion, is well known from engineering practice but still less understood in its cause-effect relationship. This note analyzes the break-away behavior of systems with nonlinear friction, which is analytically well-described by combining the Coulomb friction law with rate-independent presliding transitions and, when necessary, Stribeck effect of the velocity-weakening steady-state curve. The break-away conditions are harmonized with analytic form of the system description and shown to be in accord with a relationship between the varying break-away force and actuation force rate -- well known from the experiments reported in several independently published works.

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Michael Ruderman. 2016-10-11. On break-away forces in actuated motion systems with nonlinear friction. https://doi.org/10.1016/j.mechatronics.2017.03.007

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