Touch-sensitive interface comprising a force sensor
AssigneeHap2U
InventorsEric Vezzoli, Cédrick Chappaz
Life of this patent
Estimating the term…
Abstract
A touch-sensitive interface has a contact surface that is able to be touched by an effector (e.g., a finger). The interface includes actuating transducers (e.g., piezoelectric transducers) allowing a standing flexural wave to be formed, in a resonant mode, extending over the length of the slab. The interface includes a detector for measuring the amplitude of the wave, and a detecting circuit for determining an attenuation signal, when the contact surface is touched by an effector. It includes a processing circuit for estimating a magnitude of the force exerted by the effector on the contact surface.
Claims19
A touch-sensitive interface, comprising a plate, defining a contact surface designed to be touched by an effector, the touch-sensitive interface comprising:
- an actuating transducer, designed to exert a pressure on the plate, so as to form a stationary flexural wave extending along the plate, according to a resonance frequency, driving a vibration of the plate,
- wherein the touch-sensitive interface further comprises:
- at least one detector, designed to detect an amplitude of the flexural wave, each detector being connected to a detection circuit;
- the detection circuit being configured for forming an attenuation signal, representative of an attenuation of the flexural wave resulting from a contact between the effector and the contact surface;
- and
- a processing circuit, configured for estimating a magnitude of a force applied, by the effector, onto the contact surface, based on the attenuation signal.
A method for estimating a magnitude of a force exerted by an effector pressing on a contact surface of a plate belonging to a touch-sensitive interface, the method comprising:
- a) forming, by at least one actuating transducer, a stationary flexural wave, the flexural wave extending along the plate, according to a resonance frequency;
- b) measuring, with a detector, an amplitude of the flexural wave at a measurement time;
- c) as a function of the measurement obtained during b), obtaining an attenuation signal representative of an attenuation of the flexural wave under the effect of the force;
- and
- d) estimating the magnitude of the force, at the measurement time, as a function of the attenuation signal obtained during c).
Dependencies are inferred from the claim text.