Over the last several decades the problem of predicting dynamical contact has played a major role in the effort to understand the contact interaction between sliding surfaces. The opportunity for direct visual observation of surfaces interaction is limited thereby the study of contact area formed by wear particles has stayed unsatisfactory. Entropy models have become popular statistical models in surface damage and other contact problems, and can be useful tools for obtaining estimates of dynamical systems. We propose an alternative approach for the problem of entropy estimation, based on the Kolmogorov–Sinai entropy for a dynamical system. In this paper, we extend a previous spatial stochastic model of the bounded entropy for binary space with different sets. We consider the dynamical contact between two surfaces with three probabilistic sets of the surface contact caused by the existence of microscopic surface roughness (the set of direct contact, the non-contact set, the set of “third body” – by wear particles). Based on this model, using the Kolmogorov entropy, we find the lower and the upper bounds of entropy of the dynamical system for these three probabilistic sets. Furthermore, we make sure that the value of entropy would be within the bounds of a range of ln 2; ln 3; 2⋅ln 2 depending on the surface states.