Multi-input sliding mode control of nonlinear uncertain non-affine systems with mono-directional actuation

In this paper the control of classes of nonlinear systems characterized by uncertain non-affine dependence on the control vector and controlled by mono-directional actuators is dealt with. We consider systems with mono-directional actuators and with state and time dependent uncertainties affecting the so-called High Frequency Gain Matrix (HFGM). We propose a switching logic based on a simplex of control vectors; the presented switching logic is effective in the case when the uncertain HFGM is time and state dependent with positive unknown, time and state dependent, eigenvalues. It is then introduced an integral sliding mode method which is able to cope with non-affine systems when the control is generated by a set of mono-directional actuators.