In order to acquire high‐performance tracking control for a class of nonlinear systems with matched and mismatched modeling uncertainties, a disturbance‐compensation‐based nonlinear robust controller with a continuous control law is integrated via a novel asymptotic‐filter‐based backstepping approach. Specially, a set of novel asymptotic disturbance observers with exact estimation performance is constructed to estimate matched and mismatched total disturbances respectively in real time. Moreover, the integrated control algorithm just needs the state measurements only and does not require any internal dynamics and other physical parameter information generally. Furthermore, only the first derivative of the command to be tracked is demanded. It is noted that asymptotic output tracking performance under the closed‐loop operation can be achieved. Finally, the whole closed‐loop stability is proven strictly via the Lyapunov theoretical analysis and the feasibility of the integrated controller is demonstrated by contrastive application results.

The physics of the heat transfer process from the slider of a hard disk drive to its disk is discussed. A generalized heat transfer model, which incorporates various molecular dynamics models, is proposed to solve the heat transfer problem in thin film bearings at head-disk interface. The proposed model considers the impact of molecular collisions between film molecules and solid surfaces, which plays an important role in the heat transfer of thin film bearings and is expected to improve the accuracy of predicting the thermal protrusion caused by the heating of the slider at the head-disk interface of hard disk drives.

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