Haptic-feedback touch device with spatialized textures

A method for implementing a touch device, the touch device comprising:

• a plate comprising at least one texturing area, to which is assigned a texturing pattern that is virtual, the plate being touchable by an external body;
• at least one transducer configured to vibrate the plate in line with an ultrasonic vibration producing an ultrasonic lubrication effect between the external body and the plate, the at least one transducer being configured to be controlled by an activation signal;
• the method comprising:
• moving the external body along a texturing area of the at least one texturing area;
• determining a position of the external body on the texturing area of the at least one texturing area;
• measuring a speed of the external body along the plate;
• when the external body moves along the texturing area of the at least one texturing area, generating the activation signal, the activation signal depending on the texturing pattern, so as to activate the at least one transducer, or each of the at least one transducer, such that the activation signal results in the plate being vibrated in line with the ultrasonic vibration, the ultrasonic vibration giving rise to a change in friction between the plate and the external body, the moving external body feeling the texturing pattern as a result of its movement along the texturing area of the at least one texturing area;
• wherein:
• the texturing pattern is oriented relative to a reference axis;
• measuring the speed of the external body along the plate comprises:
• determining an angle between a trajectory of the external body and the reference axis;
• and
• calculating a projection of a speed of the external body on the reference axis based on the angle;
• generating the activation signal comprises the activation signal depending on the texturing pattern and the projection of the speed of the external body on the reference axis;
• such that, when the external body moves along the texturing area of the at least one texturing area, the friction between the plate and the external body is changed:
• with the position of the external body on the texturing area of the at least one texturing area;
• and
• with the projection of the speed of the external body on the reference axis.