“…Then, the WMR can be represented as a switching system. Afterwards, considering that the position and the orientation of the robot, (x, y, θ), and the input torques are measured, an identification scheme for the tire/road contact condition is built using algebraic numerical differentiation, which is a convenient method to estimate the time derivatives of some noisy measurements [1], [9], [10], [14], [17]. In practice, some of the parameters in the WMR model may vary because of exogenous and unknown effects, such as loading or unloading of the mobile robot, irregularity of the road surface, coefficients of the tire materials etc.…”