ABSTRACT
Abstract. The paper proposes two new fluid controllers based on the properties o f the ER fluids. The first controller is a modulated width pulse system in which the control variable is the duration of the input signal with constant amplitude. An ER valve with an on/off function assures the pulse width modulated signal. This valve operates as a hydraulic semiconductor controlled by a highvoltage signal. The second controller is developed like a new control system based on a mixed control: a conventional control o f the fluid pressure and a centralised and sequential distributed viscosity controller. The stability of the motion is proved and the conditions o f the trajectory control on the switching manifolds are determined. Two viscosity control procedures are used: a lumped control and a sequential distributed control which allows the decomposition o f the system in a finite number o f a lower dimension problems. The numerical simulations are presented.
