Patent ID: 8878657

Claim:
An haptic interface comprising: an element that interacts with a user, a rotation shaft with a longitudinal axis to which the user interaction element is fixed in rotation; an element that interacts with a fluid, the fluid interaction element being fixed in rotation to the shaft, the fluid being of magneto-rheological type; a system that generates a magnetic field in the fluid configured to modify viscosity of the fluid; a control unit configured to generate orders to the magnetic field generation system so as to modify the magnetic field; a housing containing the interaction element, the magneto-rheological fluid, and the system for generating a magnetic field, the housing including a sidewall and two end walls, the rotation shaft passing through one of the end walls and penetrating inside the housing, the housing forming a sealed chamber confining the magneto-rheological fluid; wherein the user interaction element is arranged outside the housing, the system for generating a magnetic field comprising means for generating a variable magnetic field and means for generating a permanent magnetic field, the means for generating a permanent magnetic field being arranged in the housing to cause an increase in the fluid viscosity in absence of a system electrical power supply, and the means for generating a variable magnetic field and the means for generating a permanent magnetic field are each located inside the fluid interaction element and are each immobile relative to the housing.