Classifications

• • G—PHYSICS
  • G06—COMPUTING; CALCULATING OR COUNTING
  • G06F—ELECTRIC DIGITAL DATA PROCESSING
  • G06F3/00—Input arrangements for transferring data to be processed into a form capable of being handled by the computer; Output arrangements for transferring data from processing unit to output unit, e.g. interface arrangements
  • G06F3/01—Input arrangements or combined input and output arrangements for interaction between user and computer
  • G06F3/016—Input arrangements with force or tactile feedback as computer generated output to the user
• • G—PHYSICS
  • G06—COMPUTING; CALCULATING OR COUNTING
  • G06F—ELECTRIC DIGITAL DATA PROCESSING
  • G06F3/00—Input arrangements for transferring data to be processed into a form capable of being handled by the computer; Output arrangements for transferring data from processing unit to output unit, e.g. interface arrangements
  • G06F3/01—Input arrangements or combined input and output arrangements for interaction between user and computer
  • G06F3/03—Arrangements for converting the position or the displacement of a member into a coded form
  • G06F3/041—Digitisers, e.g. for touch screens or touch pads, characterised by the transducing means
• • G—PHYSICS
  • G06—COMPUTING; CALCULATING OR COUNTING
  • G06F—ELECTRIC DIGITAL DATA PROCESSING
  • G06F2203/00—Indexing scheme relating to G06F3/00 - G06F3/048
  • G06F2203/041—Indexing scheme relating to G06F3/041 - G06F3/045
  • G06F2203/04105—Pressure sensors for measuring the pressure or force exerted on the touch surface without providing the touch position

Definitions

• the invention relates to surfaces capable of generating haptic feedback perceptible by a user, using elastic waves propagating in the surface in the ultrasonic frequency domain.
• a growing number of tactile interfaces which have a haptic feedback effect perceptible by a user. They generally use an electromechanical actuator coupled to a surface, to which they impart vibrations perceptible by a finger or a stylus of the user. They differ according to several parameters, such as the frequency of the electrical signal supplying the actuators, or its amplitude.
• a vibrating actuator produces a macroscopic mechanical deformation (of the order of a millimeter) of the pulp of the finger, at the frequency of the actuator stimulus.
• the chosen stimulus frequency must be in the range of frequencies perceptible by touch (typically 1 to 1000 Hz, most often 50Hz to 250Hz), and the vibratory amplitudes must be greater than the perception thresholds of a finger at these frequencies.
• actuators are generally thick, and require guidance of the movable part by elastic parts, as described for example in document FR3068840-A1.
• An example of the use of vibrotactile actuators is described in document WO2019094440A1, in the application in particular to game controllers or the like.
• the actuators used are low-frequency actuators, in particular of the LRA type (“Linear Resonant Actuator” or ERM (“Eccentic Rotating Masses”) chosen for their low cost in comparison with actuators of the piezoelectric type, which are expressly excluded by this document for
• LRA or ERM actuators are also selected for their ability to produce locally, that is to say directly above the actuators, an elliptical force communicated locally to the contact surface.
• vibro-tactile actuators produce movements in the axis of the finger, substantially normal with respect to the surface, that is to say out of plane, in a range of frequencies directly perceived by the mechanoreceptors of the finger. the user.
• the low-frequency vibro-tactile feedback interfaces produce noise, since the movements generated are at an audible frequency.
• the general aim of the present invention is to provide a haptic feedback interface capable of overcoming the aforementioned drawbacks of the known interfaces mentioned above.
• a particular aim of the invention is to provide a haptic feedback interface capable of producing, with the same hardware structure, several haptic effects which until now required different and incompatible structures.
• the single target interface must be able to generate both artificial texture effects based on the real-time control of the coefficient of friction and perceived during the exploration of a surface (constituting an active touch), as well as effects of low frequency vibrations capable of exciting mechanoreceptors located under the skin directly in their bandwidth (1 Hz to 1000 Hz).
• the targeted interface must be able to generate a virtual texture effect in response to a finger moving on a surface, or an effect of guiding the finger along a trajectory, which supposes the creation of a driving tangential force (for example to feel the outline of a letter or a shape), or a click or notification effect in response to a passive touch without moving the finger.
• a driving tangential force for example to feel the outline of a letter or a shape
• a click or notification effect in response to a passive touch without moving the finger.
• Another object of the invention is to provide a haptic feedback interface which does not generate any noise audible by the human ear.
• the invention consists in generating elastic waves at ultrasonic frequencies inducing movements of the particles of the surface of the interface along weakly elliptical trajectories (that is to say as close as possible to a circle ), and capable of producing forces along a privileged axis in the plane of the interface. These forces are then modulated to produce the desired haptic effect, in response to an active touch or a passive touch of the user on the surface of the interface.
• the resulting ultrasonic waves are obtained by the combination of two standing waves at the same frequency, the control signals of which are phase-shifted by 90 °.
• said standing waves are chosen so that the resulting ultrasonic wave is a traveling wave.
• the piezoelectric actuators are arranged so as to generate a wave combining a bending wave having a principal component normal to the surface of the interface, and a compression-expansion wave having a principal component tangential to the surface. of the interface.
• the surface of the interface has the shape of a rectangular plate of small thickness with regard to its length and its width, comprising on one face of the plate along one of its edges a first set of piezoelectric actuators arranged so as to generate a bending wave in the plate, and comprising on the thickness of said edge a second set of piezoelectric actuators arranged so as to generate a compression-expansion wave in the plate.
• the touch interface further comprises a contact force sensor measuring the pressing force of the user's finger on the interface surface, and a means for controlling the vibration of the surface. interface when the support force exceeds a threshold of predetermined value.
• the touch interface may also include a position sensor indicating the position of the user's finger when it is in contact with the surface of the interface, and a means for controlling the setting in vibration of this surface when the position of the user is. saved contact is in a predefined position or in a predefined area of the interface surface.
• Another subject of the invention is the use of the tactile interface described above, configured so as to generate, upon contact with a finger or a stylus, a click or notification effect in response to a passive touch of the interface surface.
• Passive touch denotes a mode of interaction in which the user places his finger on the surface without moving it in a direction tangential to the plane of the surface of the interface.
• the haptic notification is used to notify the user of the end of a task, the taking into account of an order, the presence of information to consult, etc.
• a phase jump of 180 ° is applied to the two standing waves phase shifted by 90 degrees, so as to reverse the direction of rotation of the particles set in elliptical motion, to create an impulsive sensation under the pulp of the finger. comparable to a click effect.
• the touch interface is configured so as to generate, upon contact with a finger or a stylus, an effect of guiding the finger or the stylus towards a predetermined area of the surface of the interface, in response to passive touching of the interface surface.
• the touch interface is configured so as to generate, upon contact with a finger or a stylus, a virtual texture effect by ultrasonic lubrication, in response to an active touch of the surface of the device. interface.
• active touch is meant a mode of interaction where the user moves his finger on the interface surface in a direction tangential to the plane of the interface surface, in a movement similar to a "sweep". of the interface surface.
• FIG. 2 represents a perspective view from below and from above of an embodiment of a touch interface according to the invention
• - Figure 3 shows a perspective view from below of another embodiment of a touch interface according to the invention.
• a vibrating plate 1 constituted for example by the surface glass of a touch screen, is shown in cross section.
• the plate is made to vibrate by an ultrasonic frequency wave which makes the plate 1 undulate by subjecting each elementary particle of the plate to an elliptical movement.
• the finger 5 touching the surface of the plate 1 is then driven in a direction indicated by the arrow 6, corresponding to the direction of the tangential component of the elliptical movement of the particle 4 corresponding to the point of contact.
• the trajectory 8 of the elliptical motion of a particle 4 of the surface of the plate is shown in an enlarged manner in FIG. 1B. It comprises at each instant a tangential component U corresponding to a displacement parallel to the plane of the plate, and a normal component Un corresponding to a displacement perpendicular to the plane of the plate.
• the driving force component A contributes to the ultrasonic lubricating effect, which relies on the levitation of the finger above the surface of the touch interface. In the context of the invention, this effect of levitation of the finger corresponding to the normal component Un is therefore combined with the effect of lateral drive of the finger corresponding to the tangential component U of the elliptical movement.
• Un Un COS (ü t)
• Ut and Un are the amplitudes corresponding to the length of the axes of elliptical motion
• w is the pulsation of elliptical motion
• t denotes time.
• the invention has made it possible to determine that there is an optimum ratio Ut / Un of the amplitudes Ut and Un of the tangential and normal components of the ultrasonic frequency wave producing an elliptical movement of the particles 4 of the surface, to allow obtaining different haptic feedback effects targeted in response to an active touch or a passive touch of the user, namely an ultrasonic lubrication effect, or a click, notification, or finger or stylus guidance effect.
• an interesting means consists in combining a bending wave, having a component transverse principal, with another type of vibration such as compression-expansion, having a longitudinal principal component.
• FIG. 3 Another embodiment for obtaining this same mode superposition is shown in Figure 3 and consists of replacing the actuators 3 above ( Figure 2) by actuators 2 located on the edge that is to say in the thickness of the plate 1 to be actuated.
• the actuators 3 located on the underside of the plate 1 only serve to generate bending waves and the actuators 2 located on the edge of the plate actuate only the compression-expansion waves.
• Another embodiment (not shown) consists in generating two bending waves, by means of two networks of identical piezoelectric actuators 3 placed this time on the same face of the surface 1 to be actuated, but on opposite edges.
• haptic effects in particular effects of artificial textures in response to the exploration of a surface by an active touch, or else in response to a passive touch (without displacement finger by the user), effects of guiding the finger along a path, or click or notification effects.
• the haptic interface according to the invention is excited at an ultrasonic frequency and therefore does not generate any noise audible by the human ear.
• the invention is easy to implement and integrate on a haptic surface, thanks to the small size allowed by the use of piezoelectric actuators.

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• Engineering & Computer Science (AREA)
• General Engineering & Computer Science (AREA)
• Theoretical Computer Science (AREA)
• Human Computer Interaction (AREA)
• Physics & Mathematics (AREA)
• General Physics & Mathematics (AREA)
• User Interface Of Digital Computer (AREA)
• Position Input By Displaying (AREA)
• Dental Tools And Instruments Or Auxiliary Dental Instruments (AREA)
• Percussion Or Vibration Massage (AREA)
• General Electrical Machinery Utilizing Piezoelectricity, Electrostriction Or Magnetostriction (AREA)
• Apparatuses For Generation Of Mechanical Vibrations (AREA)

Applications Claiming Priority (2)

Publications (1)

Family

ID=70228257

Family Applications (1)

Country Status (7)

Family Cites Families (13)

• 2020
  • 2020-01-30 FR FR2000932A patent/FR3106912A1/fr active Pending
• 2021
  • 2021-01-29 WO PCT/FR2021/000006 patent/WO2021152227A1/fr unknown
  • 2021-01-29 US US17/795,754 patent/US20230075405A1/en active Pending
  • 2021-01-29 JP JP2022546350A patent/JP2023513032A/ja active Pending
  • 2021-01-29 KR KR1020227026493A patent/KR20220128368A/ko unknown
  • 2021-01-29 CN CN202180011746.0A patent/CN115176217A/zh active Pending
  • 2021-01-29 EP EP21710535.2A patent/EP4097573A1/fr active Pending

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