Design and Experimental Analysis of an Adaptive Second-Order Fast Non-Singular Terminal Sliding Mode Controller for Electronic Throttle With Disturbance.

Achieving accurate and reliable tracking control for the electronic throttle (ET) with uncertainties and external disturbances is one of the most meaningful and challenging tasks. In this paper, a novel adaptive second-order fast non-singular terminal sliding mode control approach is proposed for the ET system of engines. First, the hierarchical two-layer sliding surface was designed based on the concepts of high-order sliding mode and nonlinear sliding mode, which exhibits features of chattering-free, fast response and high accuracy. Then, a novel adaptation mechanism of bidirectional gain variation was included in the modified approach to avoid the prior evaluation of the unknown disturbances and uncertainties located in the ET system. The idea behind this was to calculate the relative position between the system state and the stable point in real-time. Further, the system stability and convergence region were deduced based on the Lyapunov stability theory. Finally, in order to further prove its high control performance and adaptation capability, it was compared with the following commonly used methods: non-singular terminal sliding mode control, adaptive sliding mode control and high-order sliding mode control. Experimental verifications were conducted to validate the performance of the proposed approach considering four different test signals.