Haptic attenuation device via a passive monobloc structure.

Abstract

The invention relates to a haptic device (11) embedded in a vehicle, comprising a haptic actuator (110) having a fixed part (110a) and a moving part (110b), configured to generate a vibration of the moving part relative to the fixed part, and a deformable envelope (111) in contact with an external surface (Se) of the moving part. The deformable envelope comprises a single-piece lattice, and the vibration transmissibility coefficient associated with the deformable envelope is a function of the lattice's occupancy rate within the deformable envelope. (See Figure 2 for abbreviations.)

Description

Title of the invention: Haptic attenuation device via a passive monobloc structure. technical field

[0001] The invention relates to vibration propagation and attenuation devices, in particular associated with haptic devices generating vibrations transmitted to a contact surface, and more particularly those embedded in a vehicle, for example of the automobile type. Technological background

[0002] A haptic device is a technology that allows a user to interact with virtual or physical objects using the sense of touch. This technology relies on sensory feedback, such as vibrations, force, or movement, to create a realistic tactile sensation. Haptic devices are commonly used in training simulators, video games, virtual reality, and augmented reality, allowing users to feel textures, resistances, or forces, as if they were touching real objects. By mimicking the sensation of touch, these devices enrich the immersive experience and increase the realism of user-computer interactions.

[0003] The main advantage of transmitting vibrations generated by a haptic device to the user lies in improving user immersion and engagement. Vibrations can simulate various sensations, such as the friction of a rough surface or the force feedback of a collision. For example, in an automotive context, a haptic device can generate feedback when the user interacts with a human-machine interface (HMI), such as an HMI associated with one or more driver assistance systems and / or an in-vehicle infotainment system (IVI). Vibrations from a touch surface are emitted, for example, to validate a user action, allowing the user to know that their action has been registered by the HMI without having to look at a screen.

[0004] However, minimizing the transmission of these vibrations to the rest of the environment is essential for several reasons. First, the dispersion of vibrations can create unwanted interference or disturbances, which can affect the accuracy and effectiveness of the haptic device. Uncontrolled vibrations can cause unwanted noise or resonance that degrades the quality of the haptic experience for the user, with unwanted noise suggesting that assemblies, for example, of interior parts, are of poor quality or even synonyms for fault or damage. In addition, vibrations transmitted to the environment can cause unintentional or erroneous reactions from the sensors, leading to a decrease in the accuracy and control of the interface.

[0005] Furthermore, containing the vibrations within the haptic device itself contributes to the user's safety and comfort. Vibrations propagating outside the device could potentially cause discomfort or even damage to other sensitive equipment nearby, or to people in the environment.

[0006] Finally, isolating vibrations within the haptic device also allows for better energy management and a more optimized system design. By minimizing unnecessary dissipation of vibrational energy into the environment, the device can operate more efficiently, with reduced energy consumption and less mechanical wear. This extends the equipment's lifespan and reduces maintenance costs, while ensuring optimal performance of the haptic device to deliver a high-quality user experience. Summary of the present invention

[0007] An object of the present invention is to solve at least one of the problems of the technological background described above by designing a haptic device that makes it possible to attenuate vibrations in certain areas of the haptic device.

[0008] According to a first aspect, the present invention relates to a haptic device embedded in a vehicle, comprising: - a haptic actuator comprising a fixed part and a moving part, configured to generate a vibration of the moving part relative to said fixed part, and - a deformable envelope in contact with an external surface of the moving part, the haptic device being characterized in that the deformable envelope comprises a one-piece lattice, a vibration transmissibility coefficient associated with the deformable envelope is a function of a filling rate of the deformable envelope by the lattice.

[0009] According to one variant, the deformable structure is anisotropic, the transmissibility coefficient being defined along one direction.

[0010] According to another variant, the direction is normal to the external surface.

[0011] According to yet another variant, the vibration is generated along the direction.

[0012] According to yet another variant, the lattice is formed from at least two nested planar structures, planes comprising the planar structures of at least two planar structures being intersecting along a principal axis.

[0013] According to a further variant, the lattice is cylindrical, the lattice being formed from a planar structure wound around an axis of rotation.

[0014] According to yet another variant, the haptic actuator belongs to a set of haptic actuators comprising: • piezoelectric actuators, • rotating eccentric mass actuators, • linear resonance actuators, and • electromagnetic actuators.

[0015] According to yet another variant, the deformable envelope is included in a rim of a steering wheel of the vehicle.

[0016] The invention also relates, according to a second aspect, to an infotainment system comprising a human-machine interface and a haptic device according to the first aspect of the present invention, the human-machine interface being configured to control the haptic device.

[0017] The invention also relates, according to a third aspect, to a vehicle comprising a haptic device as described above according to the first aspect of the present invention or an infotainment system according to the second aspect of the present invention. Brief description of the figures

[0018] Other features and advantages of the present invention will become apparent from the description of the particular and non-limiting embodiments of the present invention below, with reference to the attached Figures 1 to 4, in which:

[0019] [Fig-1] schematically illustrates part of a vehicle passenger compartment, according to a first particular and non-limiting example of a realization of the present invention;

[0020] [Fig.2] illustrates a cross-sectional view of a haptic device in a first configuration, according to a first particular and non-limiting embodiment of the present invention;

[0021] [Fig. 3] illustrates a cross-sectional view of a haptic device in a second configuration, according to a second particular and non-limiting embodiment of the present invention; and

[0022] [Fig.4] schematically illustrates two particular embodiments of a lattice of the haptic device of the first or second figure according to particular and non-limiting examples of the present invention. Description of examples of achievements

[0023] An example of a haptic device for a vehicle will now be described with reference to Figures 1 to 4. According to this example, a haptic device or an infotainment system including such a device installed in a vehicle, comprises a haptic actuator including a fixed part and a moving part, configured to generate a vibration of the moving part relative to the fixed part, and a deformable envelope in contact with an external surface of the moving part. Indeed, the deformable envelope comprises a monobloc lattice and a vibration transmissibility coefficient associated with the deformable envelope is a function of the lattice's filling rate within the deformable envelope.

[0024] The terms "first," "second" (or "firsts," "seconds"), etc., are used in this document by arbitrary convention to allow for the identification and distinction of different elements (such as operations, means, etc.) implemented in the embodiments described below. Such elements may be distinct or correspond to a single element, depending on the embodiment.

[0025] Fig. 1 schematically illustrates part of the passenger compartment of a vehicle 10, for example, a motor vehicle. In other examples, the vehicle 10 corresponds to a coach, a bus, a truck, a utility vehicle or a motorcycle, i.e., a motorized land vehicle.

[0026] Vehicle 10 corresponds for example to a vehicle with a thermal engine, with electric motor(s) or even a hybrid vehicle with a thermal engine and one or more electric motors.

[0027] The vehicle 10 incorporates one or more systems such as an infotainment system, referred to as an IVI system, or driver assistance systems, referred to as ADAS (Advanced Driver-Assistance System). In order to interact with, or even control, a system embedded in the vehicle 10, an embedded system includes a human-machine interface, referred to as an HMI or user interface.

[0028] Such an HMI is a device or set of devices enabling interaction between a human and a machine or computer system, in this case, an embedded system of vehicle 10. The main objective of an HMI is to make this interaction as intuitive, efficient, and natural as possible, thereby facilitating the use of the embedded system by the user, in this case, a passenger or driver of vehicle 10. This HMI includes, for example, one or more screens, touch-sensitive or not, as well as controls such as buttons, arranged in various locations within the passenger compartment so as to make them visible and accessible to the user. The HMI is thus designed to facilitate the use of an embedded system by the user, by providing understandable means of control and feedback.

[0029] To improve the HMI, it includes a haptic device. Indeed, the technology of a haptic device allows the user to receive feedback through touch. This can include vibrations, forces, simulated textures, or resistance feedback. The advantages of combining a haptic device with an HMI are numerous.

[0030] Indeed, haptic feedback provides additional information that can complement visual and auditory information. For example, a vibration emitted by the haptic device towards the user can indicate that an action has been registered or that a limit has been reached, thus improving the user's understanding and the efficiency of this interaction. For example, if the vehicle 10 is equipped with cruise control, a vibration emitted towards the driver when the driver activates the cruise control function allows the driver to be certain that their activation action has been registered by the system responsible for regulating the speed of the vehicle 10.

[0031] Moreover, in virtual reality or simulation applications, particularly those associated with the infotainment system, haptic feedback adds an additional dimension of realism and immersion, allowing users to "feel" digital objects or environments as if they were real.

[0032] Thus, the association of a haptic device with an HMI enriches user interaction by adding tactile feedback, improving the precision of user actions and the safety of driving the vehicle 10, or tactile effects further improving the user's immersion in an application associated with the infotainment system, this association improving driving comfort and / or the perceived quality of applications used by a passenger of the vehicle 10.

[0033] According to the example in [Fig. 1], the passenger compartment of the vehicle 10 includes a steering wheel, enabling a driver of the vehicle 10 to steer it. The steering wheel includes, in particular, a rim 101, which is rectangular in shape. Of course, any shape of steering wheel rim is possible; the rim may, for example, be circular or oblong, with or without a flat section. The rim 101 further includes a haptic device, which constitutes the structure of the rim 101 or, in another example, a part of the rim 101's surface.

[0034] Such a haptic device is, for example, associated with a screen (not shown), which is installed in the center of the steering wheel and is associated with a touch interface (not shown), the touch interface being integrated into the screen which is then a touch screen, or integrated into the rim 101, touch sensors being placed in the latter.

[0035] Fig. 2 illustrates a cross-sectional view of a haptic device 11 in a first configuration, according to a first particular and non-limiting embodiment of the present invention, for example the touch device placed in the rim 101 of the steering wheel of the vehicle 10.

[0036] The haptic device 11 includes at least one haptic actuator 110. Such a haptic actuator is known to a person skilled in the art; the haptic actuator 110 belongs, for example, to a set of haptic actuators comprising one of the following types of actuators. • Piezoelectric actuators, which use piezoelectric materials that deform when subjected to an electric field. This rapid deformation generates high-frequency vibrations and very precise movements. They are often used in devices requiring fast and accurate responses, such as the touchscreens of some mobile devices. • Rotating eccentric mass actuators, also called ERMs, use an eccentric mass attached to a motor that rotates at high speed. The rotation of this mass creates a vibration felt by the user. They are commonly used in mobile phones and game controllers. • Linear resonant actuators, also called LRAs, consist of a moving mass connected to a spring, which vibrates at a resonant frequency when an alternating current is applied. This type of actuator produces more targeted and efficient vibrations compared to ERMs, with a more controlled frequency response. • Electromagnetic actuators, operating on the principle of electromagnetism, where an electric current is used to generate a magnetic field that produces movement. Moving-coil motors are an example of this technology. • Other types of actuators are also known, such as pneumatic and hydraulic actuators, shape memory alloy actuators, also called SMA, ultrasonic actuators or Electroactive Polymer EAP actuators, also called EAP.

[0037] Each type of haptic actuator has its own advantages and disadvantages, and the choice of an actuator depends on the specific application, cost constraints, size, accuracy and frequency response required.

[0038] Figure 2 shows the haptic actuator 110 with a fixed part 110a and a The moving part 110b, separated for example by a vacuum or air gap, and corresponding, for example, to a cross-sectional view of an electromagnetic actuator. Obviously, the other types of actuators mentioned above can also be used to equip the haptic device 11. The fixed part 110a is, for example, integral with the structure of the rim 101. By fixed part, we mean a part that is not moved when the haptic actuator 110 is activated. Indeed, the frame of reference used in this description is that of the steering wheel and therefore of the rim 101, which is indeed mobile in the frame of reference of the vehicle 10, if only in rotation around an axis described by a steering column or a hub. The moving part 110b, on the other hand, is set in motion relative to the fixed part 110a when the haptic actuator 110 is activated.Note that this activation is carried out for example when a motor of the haptic actuator 110 is electrically powered, i.e. when a voltage. a non-zero voltage is applied to its terminals, or a magnetic system receives an electrical signal having a certain input frequency, whether the frequency is stable or not.

[0039] The moving part 110b includes, in particular, an external surface 'Se', which receives a deformable envelope 111. The deformable envelope 111 comprises a first surface 'SI', which is in contact with the external surface 'Se' of the moving part 110b, and a second surface 'S2' distal to the moving part 110b. The first surface 'SI' and the second surface 'S2' are thus separated by a distance equal to the nominal thickness of the deformable envelope 111.

[0040] The deformable envelope 111 comprises a one-piece lattice; in other words, the material constituting the deformable envelope 111 forms a lattice made of a single piece. Such a lattice is obtained, for example, by a three-dimensional printing process, by a machining process in a block of material, or by laser cutting a sheet of material shaped after cutting.

[0041] Fig. 4 schematically illustrates two particular embodiments of this lattice according to particular and non-limiting examples of the present invention.

[0042] According to a first particular embodiment, the lattice 1111 forming the deformable envelope 111 is formed from several plane structures 40 nested one inside the other. Each plane structure 40 is arranged along a plane, a first plane structure 40a along a first plane 'PI' and a second plane structure 40b along a plane 'P2', the first and second planes 'PI' and 'P2' being intersecting along the principal axis AL. The first and second planes 'PI' and 'P2' are, according to this particular embodiment, normal, the second plane structure 40b corresponding to a rotation of the first plane structure 40a through an angle of ninety degrees (90°) around the principal axis 'Al'.Other planar structures 401a, 402a, 401b, 402b are then repeated along planes parallel to the first plane 'PI' or the second plane 'P2' so as to create a repeating mesh along the directions included in the first plane 'PI' and in the second plane 'P2' normal to the main axis 'Al'.

[0043] According to other particular embodiments, the lattice forming the deformable envelope 111, formed from several planar structures nested within one another, comprises 'n' planar structures arranged in 'n' planes intersecting the principal axis Al, 'n' being an integer greater than two. The 'n' planes are distinct and include the principal axis 'Al', the 'n' planes being arranged in pairs at an equal angle, for example, of 180° / n.

[0044] According to another particular embodiment, the lattice 1112 forming the deformable envelope 111 is cylindrical, the lattice 1112 being formed from a structure plane 40 similar to the plane structure presented previously and wrapped around an axis of rotation 'A2'.

[0045] The plane structure 40 is, for example, regularly perforated, the openings then forming a geometric pattern such as a mashrabiya. This plane structure 40 is, according to the examples illustrated in [Fig. 4], symmetrical with respect to an axis 'As', which coincides, for example, with the principal axis 'Al' according to the first particular embodiment illustrating the lattice 1111. This plane structure 40 is obtained by repeating a basic pattern 41, which comprises crossbars formed by beams, the beams being the material remaining after hollowing, for example. The mechanical behavior of such a plane structure is then different along certain directions. For example, the plane structure 40 is very flexible along the direction defined by the axis of symmetry 'As', while its rigidity is greater along an axis normal to the axis of symmetry 'As'.The lattice 1111, 1112 formed from such a planar structure 40 is then anisotropic, making the deformable structure composed of this lattice 1111, 1112 itself anisotropic. The Young's modulus, the vibration transmissibility coefficient, and the thermal conductivity of the deformable structure are therefore different depending on the direction. These different coefficients are also a function of the degree to which the lattice fills the deformable structure 111.

[0046] As introduced with reference to [Fig. 2], the first surface 'SI' of the deformable envelope 111 is in contact with the external surface 'Se' of the haptic actuator 110, and more specifically with the moving part 110b of the haptic actuator 110. Thus, the vibrations generated by the haptic actuator 110 set the moving part 110b in motion relative to the fixed part 110a, and, through the contact between the deformable envelope 111 and the moving part 110b, which makes the first surface 'SI' and the external surface 'Se' coincide, the deformable envelope 111 is subjected to these same vibrations. A vibration transmissibility coefficient associated with the deformable envelope 111 is a function of the lattice's occupancy rate of the deformable envelope 111. Thus, for a first filling rate, this vibration transmissibility coefficient has a first value of 'kl'.When the filling rate of the deformable envelope increases, the density of the lattice increases, the transmissibility coefficient then increases with this filling rate and then has a second value 'k2', the second value 'k2' being greater than the first value 'kl'.

[0047] The steering wheel rim 101 is, for example, made with a filling ratio of the deformable shell 111 that varies according to different areas. This filling ratio is, for example, low in the areas where the palm of the hand grips, so as to avoid any transmission of vibrations generated by the actuator. In the haptic zone of the steering wheel grip, the driver does not feel the vibrations generated by the haptic device. Conversely, in specific areas, for example in the areas receiving the driver's fingertips, the filling of the deformable envelope 111 is high, thus allowing the driver to feel the vibrations generated by the haptic actuator 110 and transmitted locally through the deformable envelope 111, which forms part of the rim 101. Thus, the vibrations are attenuated by the deformable envelope 111 with low filling due to the lattice, while they are transmitted without attenuation, or even amplified, by the deformable envelope 111 with higher filling, the density of the lattice being greater in this latter area compared to that of the less filled deformable envelope 111.

[0048] According to the particular embodiment in which the deformable envelope 111 is anisotropic, the transmissibility coefficient is defined along a direction, for example along a direction normal to the external surface 'Se' and therefore normal to the first surface 'SI', the vibration being generated along this same direction, i.e. that the moving part 110b of the haptic actuator moves relative to the fixed part 110b of the actuator along this same direction.

[0049] Figure 3 illustrates a cross-sectional view of a haptic device in a second configuration, according to a second particular and non-limiting embodiment of the present invention and for which the filling ratio of the deformable envelope is greater than that illustrated in [Fig.2]. This higher filling ratio is obtained according to two possible embodiments.

[0050] According to the first embodiment, the dimensions of the basic pattern 41 change without changing the amount of material present to form a basic pattern 41. The basic pattern 41 is, according to the example illustrated in [Fig. 3], shorter than that illustrated in [Fig. 2], the height being defined along the direction normal to the first surface 'SI'. The change in the infill percentage resulting from this change in dimensions is obtained during the manufacturing of the rim 101, for example, if it is obtained by three-dimensional printing or 3D printing, the dimensions of the basic pattern 41 are different in different locations on the rim 101, thus generating a heterogeneous material whose local properties differ depending on the location of the rim 101 considered.Similarly, if the deformable envelope 111 includes a lattice obtained by cutting, for example by laser cutting, then the openings are smaller or more numerous for the same lattice surface area. Thus, when the deformable envelope 111 is at rest, the transmissibility coefficient is itself heterogeneous and allows the vibrations generated by the haptic actuator 110 to be filtered so that the second surface 'S2', corresponding to the surface of the rim 101 in contact with a part of the user's body, here the driver of the vehicle 10, vibrates only in certain areas. predefined. Thus, by precisely defining the surfaces of the rim 101 that should vibrate or not, it is possible to transmit vibrations only to the expected receivers and to avoid any unintended propagation of vibrations to other elements of the steering wheel for example.

[0051] According to a second particular embodiment, the change in the dimensions of the basic pattern 41 results from a compression of the deformable envelope 111 and therefore of the basic pattern 41 under the action of a force applied by a part of the body 100 of a user on the second surface 'S2' or under the action of a pressure distributed on the second surface 'S2'. Thus, the coefficient of vibration transmissibility from the first surface 'SI' to the second surface 'S2' is a function of a compression ratio of the lattice, the compression ratio being a function of the force or the pressure and results from the presence of a part of the body '100' of a user in contact with the second surface 'S2', the transmissibility coefficient being: • equal to the first value 'kl' when the part of the body 100 is absent, and • equal to the second value 'k2' when the part of the body 100 is present. The presence of part 100 of the body signifies the application of a force or pressure on the second surface 'S2', while the absence of part 100 of the body signifies a free second surface 'S2' or a deformable envelope 111 at rest. The transmissibility coefficient is then a function of the pressure or force exerted on the second surface 'S2'.

[0052] According to a particular embodiment different from the two previously developed embodiments but which can nevertheless be combined with at least one of these particular embodiments, the material composing the lattice is temperature-sensitive and its mechanical behavior changes depending on the temperature of the lattice. Thus, when a portion of the body 100 is present, i.e., in contact with the second surface 'S2' of the deformable envelope 111, this portion being warmer than the ambient temperature, it heats the lattice material near the second surface 'S2', i.e., the temperature of the lattice increases locally, whereas in the absence of the portion of the body 100, the lattice remains at an ambient temperature lower than the temperature of the portion of the body 100. The material composing the lattice is, for example, a crystalline or semi-crystalline polymer.Indeed, at low temperatures, such a material is in an amorphous and relatively flexible state, but as the temperature increases, it crystallizes further, which temporarily increases its rigidity and therefore its Young's modulus. Since the vibration transmissibility coefficient is a function of the Young's modulus of the material composing the lattice, this transmissibility coefficient is then a function of the local temperature and therefore of the temperature of the deformable envelope 111 at the level of the second surface 'S2'. In this way, the presence of the hand... The driver of the vehicle 10 on the steering wheel rim improves the transmission of vibrations generated by the haptic actuator 110.

[0053] Such a haptic device comprising a deformable envelope made with a lattice which changes spatial distribution locally and can deform under the effect of the presence of the user aims to limit the perception of vibrations in certain areas of this haptic device.

[0054] In the case of a haptic steering wheel, vibrations which are emitted to be perceived under the finger are conversely dampened by the deformable envelope so as to avoid being felt by the palm of the hand, thus allowing the palm of the hand to feel vibrations only from elements external to the haptic device, for example to perceive vibrations generated by the road surface on which the vehicle travels or by a defect in the steering of the vehicle.

[0055] It is therefore necessary to filter differently the vibrations which propagate from the haptic actuator to the fingers and the palm of the hand, which the steering wheel rim located at the interface between the two does when it includes the deformable envelope, the steering wheel rim is thus designed as a part for filtering vibrations coming from the haptic actuator.

[0056] Modifying the local behavior of the haptic device makes it possible to obtain, for example, a magnifying effect and to collect vibratory energy that would otherwise have been diffused homogeneously.

[0057] Such a haptic device therefore makes it possible to eliminate certain effects related to noise, for example, while allowing the focusing of vibratory effects, with an attenuation of the amplitude of the vibrations emitted by the haptic actuator on one side and a transmission of vibrations in an expected contact area.

[0058] Of course, the present invention is not limited to the embodiments described above but extends to a vehicle infotainment system that would include additional elements without departing from the scope of the present invention. Similarly, the invention is not limited to integration in a steering wheel rim but extends to integration in any device intended to be in contact with a part of a user's body, for example, a pedal, a seat, or a headrest.

[0059] The present invention also relates to a vehicle, for example an automobile or more generally an autonomous land-based motor vehicle, comprising a haptic device or an infotainment system comprising a haptic device as shown opposite Figures 1 to 4.

Claims

Demands

1. Haptic device (11) embedded in a vehicle (10), comprising: - a haptic actuator (110) comprising a fixed part (110a) and a moving part (110b), configured to generate a vibration of said moving part (110b) relative to said fixed part (110a), and - a deformable envelope (111) in contact with an external surface (Se) of said moving part (110b), the haptic device (11) being characterized in that the deformable envelope (111) comprises a one-piece lattice, a transmissibility coefficient of said vibration associated with the deformable envelope (111) is a function of a filling rate of said deformable envelope (111) by said lattice.

2. Haptic device (11) according to claim 1, wherein the deformable structure (11) is anisotropic, said transmissibility coefficient being defined along one direction.

3. Haptic device (11) according to claim 2, wherein said direction is normal to said external surface (Se).

4. Haptic device (11) according to claim 3, wherein said vibration is generated along said direction.

5. Haptic device (11) according to any one of claims 1 to 4, wherein the lattice is formed from at least two nested planar structures, planes comprising the planar structures of said at least two planar structures being intersecting along a principal axis (Al).

6. Haptic device (11) according to any one of claims 1 to 4, wherein the lattice is cylindrical, the lattice being formed from a planar structure wound around an axis of rotation (A2).

7. Haptic device (11) according to any one of claims 1 to 6, wherein the haptic actuator (110) belongs to a set of haptic actuators comprising: • piezoelectric actuators, • rotating eccentric mass actuators, • linear resonance actuators, and • electromagnetic actuators.

8.

9.

10. Haptic device (11) according to any one of claims 1 to 7, wherein the deformable envelope (111) is contained within a rim of a steering wheel of the vehicle (10). Infotainment system comprising a human-machine interface and a haptic device (11) according to any one of claims 1 to 8, said human-machine interface being configured to control said haptic device (11). Vehicle (10) comprising a haptic device (11) according to any one of claims 1 to 8 or an infotainment system according to claim 9.

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