Improved Haptic Control Device

Abstract

The present invention relates to a haptic control device comprising an electric motor (100) provided with a stator (110) comprising a plurality of wound teeth (112), said teeth (112) extending radially from an annular yoke and an external rotor (120) comprising a plurality of magnetized magnetic poles arranged on the inner surface of a ferromagnetic tubular yoke (123) and facing the end of the wound teeth (112) to form a magnetic air gap (230), a user interface (2) mechanically connected to said rotor (120), a braking means (200). This braking means (200) acts directly on at least one external tubular surface (250) of said tubular yoke (123) of the rotor (120) of the motor (100) / A computer ensures the control of said electric motor (100) on the one hand and said braking means (200) on the other hand as a function of the signal delivered by said angular position sensor and a control law.Abstract Figure: Figure 1.

Description

Title of the invention: Haptic device with improved control Technical field of the invention

[0001] The invention relates to a haptic device for controlling a rotating member, typically a steering wheel or handlebar of a vehicle, or a control wheel of industrial equipment, a joystick or a yoke / half-steering wheel (in English "yoke") for guidance, or even peripherals for driving simulators or exoskeleton joints.

[0002] Such devices are intended to provide a human operator with perceptible feedback on the state of the controlled organ, so as to enable him to intuitively understand the situation and the forces exerted on the controlled organ, and which could be masked by assistance exceeding the forces exerted voluntarily by the user.

[0003] It is also useful to be able to brake the rotation of a steering wheel, in certain particular situations, for example when the wheels come up against a curb, to make the driver feel this situation clearly perceptibly, or when a helpless or drunk driver leans on the steering wheel to help him / her get out of the vehicle. It is then important that the steering wheel is firmly held to allow the driver to lean on the steering wheel to maintain his / her balance. Another context concerns the limitation of the angular rotation travel, without a mechanical stop, to prevent the steering wheel from being turned several times, which would lead to the wires of the airbag mounted in the head of the steering wheel being torn off. Also when driving on the motorway, it may be useful to brake the rotation of the steering wheel sharply to avoid skidding. state of the prior art

[0004] Patent application WO2022123088Al is known in the prior art, which relates to a haptic control device provided with a magnetorheological braking system comprising a fixed support and two braking components. One of the two braking components is connected in a rotationally fixed manner to the support. The two braking components can rotate relative to each other continuously about an axis of rotation. A first braking component extends along the axis of rotation and comprises a core made of magnetically conductive material. The second braking component comprises a hollow shell portion which extends around the first braking component. Axially spaced peripheral braking gap portions at least partly filled with a magnetorheological fluid are formed between the first and second braking components.

[0005] Patent EP1698538B1 describes a haptic feedback device comprising a motor; a user contact element that contacts a user, during use, to provide haptic feedback; and a brake for selectively applying a braking force to the user contact element, characterized in that the device also comprises a magnetorheological clutch for selectively coupling the motor with the user contact element; and an electronic force feedback control system that is configured to drive the brake and the clutch, during use, so as to provide haptic feedback to the user.

[0006] Patent EP3707583B1 relates to a haptic feedback device comprising:

[0007] - a body capable of forming an interface with a user;

[0008] - contact means capable of establishing contact with a surface of a system capable to contain information;

[0009] - a first actuator connected to the contact means and capable of applying a translational movement of said contact means relative to said body;

[0010] - braking means capable of applying mechanical resistance to the movement relative between the means of contact and the body;

[0011] - a second actuator capable of varying the mechanical resistance applied by the braking means. Disadvantages of the prior art

[0012] The solutions of the prior art provide a combination between two coupled electromagnetic systems, an electric motor on the one hand and a braking system, generally magnetorheological, which act on the member of interaction with the user. These solutions are relatively bulky and the mechanical coupling between the braking system and the motor introduces latencies and artifacts reducing the dynamics of the haptic system. Furthermore, magnetorheological braking has a hysteresis limiting the reactivity of the haptic system and not allowing faithful feedback to be restored with sufficient resolution. Statement of the invention

[0013] The present invention aims to overcome the drawbacks of the state of the art by making it possible to improve the haptic rendering performance and the size of haptic devices integrating an electric motor and a braking means.

[0014] To do this, the present invention proposes a haptic control device comprising - an electric motor provided with a stator comprising a plurality of wound teeth, said teeth extending radially from an annular yoke and an external rotor comprising a plurality of magnetic poles magnets arranged on the inner surface of a ferromagnetic tubular yoke and facing the end of the wound teeth to form a magnetic gap, - a user interface mechanically connected to said rotor - an electronic card comprising the means for controlling said electric motor, - an angular position sensor providing the position of said user interface - a means of braking characterized in that - said braking means acts directly on at least one external tubular surface of said tubular yoke of the engine rotor - in that it comprises a computer controlling on the one hand said electric motor and on the other hand said braking means as a function of the signal delivered by said angular position sensor and a control law. According to variants: • The device further comprises an elastically deformable element • said position sensor comprising two members secured to each of the ends of said elastically deformable element (to provide a signal of the relative angular position of these two members. • one of the members is composed of interdigitated toothed crowns, the other of said members being a multipolar magnetized ring, said sensor further comprising flux collectors making it possible to guide the magnetic flux between the toothed crowns, said collectors forming between them an air gap in which a magneto-sensitive probe is housed. • said rotor has at least one second ferromagnetic tubular yoke defining an additional braking interaction surface, said braking means acting directly on the outer surface of said first tubular yoke of the motor rotor and on at least one inner surface of said tubular yoke • the electrical connection between said motor and said position sensor is made by a locally delaminated printed circuit. • the electronic card also includes the means for controlling the braking system • said braking means has a nominal response time at least eight times greater than the nominal response time [i.e. at identical supply voltage] of said motor. • said electronic card includes a voltage converter to supply said braking system with a voltage higher than the supply voltage of said motor. • The device comprises a means for detecting the presence of hands on a steering wheel constituted by said position sensor and a calculator applying a function taking into account at least one derivative of the position signal • said braking means consists of at least one electrically actuated friction element movable between a position spaced from said rotor yoke and a position of tribological interaction with said yoke. • said braking system consists of a magnetic hysteresis brake. • the brake device is provided with an annular ferromagnetic core cooperating with at least one electric coil and arranged concentrically with said electric motor, said ferromagnetic core forming with the ferromagnetic yoke of the rotor a second air gap in which a magnetorheological material is arranged. • said magnetorheological material is a magnetorheological fluid accompanied by a sealing means. • the motor and the brake device are integrated into a housing, the electronic card being integrated into a central control unit located outside said housing. brief description of the figures

[0015] Other characteristics and advantages of the invention will emerge from the following reading of detailed embodiment examples, with reference to the appended figures which represent respectively:

[0016] [Fig-1] [Fig.l] represents a schematic view of a haptic device according to the invention

[0017] [Fig.2] [Fig.2] represents a schematic view of a first example of a sheave lization of a haptic device according to the invention

[0018] [Fig.3] [Fig.3] represents a schematic view of a second example of a sheave lization of a haptic device according to the invention

[0019] [Fig.4] [Fig.4] represents a schematic view of a second example of a sheave lization of a haptic device according to the invention

[0020] [Fig.5] [Fig.5] represents a schematic view of a second example of a sheave lization of a haptic device according to the invention Principle of the invention

[0021] The invention is intended to improve and secure the operation of a haptic device and to provide extended haptic feedback, both for low amplitude and low power movement situations and for situations where ional arrival at the end with high torques. The principle of the invention consists of associating, in the same compact device, a. a motor, providing high dynamic movements, but limited in torque, with b. a braking means, with low dynamics but higher torque, both being jointly controlled by a computer whose input receives a signal from an angular position sensor integrated into the device or at least coupled to the driven rotating member.

[0022] This signal is constituted either by an angular position signal, or by a differential angular position signal of two parts of a segment of a torsion shaft, or even a torque signal exerted on a segment of a torsion shaft determined as a function of the relative angular position. The computer optionally applies processing to determine a torque signal from the differential angular position signal provided by the position sensor, as proposed in patent FR2972896 for example.

[0023] This calculator can be integrated into the device or remote, it could in particular be integrated into a central control electronics of a motor vehicle. The calculator optionally receives other contextual input signals.

[0024] This torque is the torque exerted by the driving member (for example the steering wheel), and the driven member (for example the steering system or the simulator sensor).

[0025] The braking means consists, in a non-exhaustive manner, of: - a braking system comprising one or more parts interacting by friction with the surface of the engine cylinder head, and actuated by an electromagnetic actuator, - a braking system acting magnetically by magnetic hysteresis with the cylinder head of said engine, - a braking system acting magnetically via a magnetorheological material with the cylinder head of said engine, - and more generally any electrically controllable braking solution to interact reversibly with the cylinder head of the electric motor.

[0026] An important aspect of the invention is that the braking means interacts directly and without intermediate parts with the cylinder head of the engine in order to reduce the size and avoid any assembly of parts likely to distort the mechanical interaction between the braking means and the electric motor, and in order to guarantee that the control controlled by the computer does not undergo any mechanical artifact during its application to the engine and the braking means.

[0027] Optionally, part or all of the electronic components necessary for controlling the electric motor, such as the power switches and the computer, are arranged on an electronic card integrated into the haptic device. This electronic card can also include the brake control means.

[0028] Also optionally, the electronic card has a voltage converter making it possible to supply the braking system with a voltage different from the voltage of the electric motor. Detailed description of a general example

[0029] [Fig.l] represents a schematic view illustrating the general principle of the invention.

[0030] The device comprises three sub-assemblies, namely an electric motor (100), a braking means (200) and a position sensor (300), associated with a driving member constituted by a shaft (1) coupled to a user interface, for example a flywheel (2), and a driven member (3) constituted by the rotor (120) of the electric motor (100), integral with the shaft (1) and concentric with the stator (110).

[0031] The motor (100) is a motor with an external rotor (120) surrounding the stator (110), to define in a known manner a tubular air gap (150). The rotor (120) comprises in a known manner magnetized poles (125), for example made from a plurality of magnets, or by multipolar magnetization of the same magnet.

[0032] The stator (110) of the motor comprises a plurality of teeth (112) extending radially towards the rotor (120). Some or all of the teeth (112) carry electrical coils (111).

[0033] The stator (110) is integral with the frame (5). One or more bearings (510, 520) ensure the guidance of the shaft (1) relative to the frame (5). These bearings (510, 520) can be plain bearings, rolling bearings or any other guiding means known to those skilled in the art.

[0034] The rotor (120) has a tubular outer surface (250) ensuring interaction with the braking means (200). Depending on the type of braking, it may have a tribological surface condition adapted to said associated braking means.

[0035] The braking means (200) surrounds the motor (100) and in particular the rotor (120). The shaft (1) carries a target (320) positioned opposite a probe (310), to form an angular position sensor (300) determining the angular position of the shaft (1) relative to the frame (5). The angular sensor may be a magnetic sensor, an inductive sensor, an optical sensor, or any other type of sensor known to those skilled in the art involving a probe and a beacon whose angular displacement is measured by said probe.

[0036] A printed circuit (400) is arranged, in the example described without limitation, transversely; it is crossed by the axis (1). The electrical coils (111) of the motor as well as the braking means (200) are electrically connected to this printed circuit (400) by electrical connections (401, 402).

[0037] To ensure the braking of the rotor (120), the activation of the braking means (200) secured to the frame (5) is controlled by an electrical signal produced by the electronic circuit (400). This activation can be electromechanical, for a mechanical braking means, or electrical for a magnetostrictive or magnetorheological braking means.

[0038] It is specified that the detailed description of the torque sensor is not limited to a magnetorheological type braking means and can be implemented with any other electrically controlled braking means. First variant of realization

[0039] [Fig. 2] represents the schematic diagram of a second, more specific embodiment of the invention. This example provides a magnetorheological type braking means, as well as an example of connection between the motor and the angular position sensor, and of configuration of the angular position sensor.

[0040] In this embodiment variant, the electronic circuit comprises two printed circuits (410, 420) connected by a flexible ribbon cable (430). The first printed circuit (410) comprises the electronic components for controlling the motor as well as for controlling the braking means (200). The second printed circuit (420) placed in a plane parallel to that of the first printed circuit (410) supports the probe (310). The flexible ribbon cable (430) can be produced in different ways, either by using a ribbon cable connected to each of the PCBs by a connector, or by a technique of delaminating the resinous layers of a PCB to produce the ribbon cable directly in the internal copper layer of this PBC, or by any means known to those skilled in the art. The aim is to ensure the connection of two electronic cards in a reliable and inexpensive manner.

[0041] It is specified that the description of the magnetorheological braking means is not limited by the characteristics of the connection system or of the position sensor, the description of this magnetorheological braking means being relevant for possible other connection solutions and / or other types of angular position sensor.

[0042] By way of example, the braking means (200) is constituted by a magnetorheological fluid (210), filling a tubular air gap (230) closed at its axial ends in a sealed manner by two O-rings (211, 212), and by excitation coils (220) positioned in said braking means concentrically to the rotor (120).

[0043] Similarly, the detailed description of the angular position sensor is not limited to a magnetorheological type braking means and can be implemented with any other braking means. The same applies to the configuration of the angular position sensor. THIRD variant of implementation

[0044] [Fig. 3] represents the schematic diagram of a third, more specific embodiment of the invention. In this embodiment, the braking means (200) acts on two coaxial peripheral surfaces (250, 260) of the rotor (120). For this purpose, the rotor (120) has a tubular yoke (124) in which the braking means (200) is housed, having a tubular configuration and acting on the two inner and outer tubular surfaces of the rotor (120). In the case of magnetorheological braking, the magnetorheological liquid is activated by excitation coils.

[0045] DETAILED VIEW OF ANOTHER EXAMPLE OF EMBODIMENT OF THE INVENTION

[0046] Figures 4 and 5 represent different views of a device according to the invention, [Fig.4] representing an axial couple view and [Fig.5] an exploded perspective view of this device. It has a magnetorheological type braking means (200), exploiting the modification of the viscosity of a magnetorheological fluid using the electric coils (220), the magnetorheological fluid being placed in contact with the rotor (110) and the modification of its viscosity causing a modulation of the friction forces on the rotor (110).

[0047] The electric motor (100) and the braking means (200) are arranged concentrically, the braking means (200) encompassing the electric motor (100). The stator (110) and the braking means (200) act magnetically on the tubular rotor yoke (123) housed between these two elements. The tubular rotor yoke (123) is ferromagnetic and forms, at its outer surface (250), and with the braking means (200), a magnetic air gap (230) which contains magnetorheological fluid. The tubular rotor yoke (123) carries, at its inner surface, a magnetized ring (125) and forms with the stator (110) a second magnetic air gap (150). Thus the stator (110) and the braking means (200) act directly on the same tubular yoke (123) so as to control its movement as precisely as possible.In order to increase the braking capacities of said associated means, the rotor (120) is provided with a second ferromagnetic tubular yoke (124) surrounding the braking means (200) and forming with it a second magnetic air gap (135) containing magnetorheological fluid. The braking means therefore acting on the inner surface (260) of the second tubular yoke (124). The rotor has two concentric bells, formed by the tubular yokes (123, 124), the annular-shaped braking means (200) being housed between these two bells and exerts a magnetic braking force on each of them and the cylindrical-shaped stator (110) is housed within the inner bell formed by the inner tubular yoke (123).

[0048] The tubular yokes (123, 124) are connected at their distal end, the end opposite the coupling zone (10) of the shaft (1) with the member to be driven, to a disc partition (122). Said disc partition (122) extends radially from a tube (121) allowing the rotor (120) to be guided in rotation. Said tube (121) is concentric with the tubular yokes (123, 124) and extends in the same direction, these 3 elements therefore being secured to each other at their distal end and left free at their proximal end, that located on the side of the coupling zone (10) of the shaft (1), so as to be able to assemble the rotor (120) with the stator (110) and the braking means (200). The stator (120) is provided, at its axis, with a cylindrical through cavity to allow the insertion of the tubing (121) of the rotor (120).Guide bearings (510, 520), in the form of rings provided with a shoulder, arranged at the axial ends of the stator between the outer periphery of the tube (121) and the inner periphery of the cylindrical cavity passing through the stator (110) make it possible to ensure the guidance of the rotor (120).

[0049] The frame (5) is produced by plastic molding. Its production method consists of precisely positioning the stator (110) and the braking means (200) in the injection mold and overmolding the latter, at their proximal end, with the plastic resin forming the frame so as to obtain a solid assembly. The assembly thus produced has a cylindrical reception zone (56), opening on the distal side and delimited by a transverse partition (55) on the proximal side, in which the stator and the braking means expand, while leaving free the zones necessary for the insertion of the rotor, namely an annular space between the stator and the braking means and an annular space at the periphery of the braking means to accommodate the tubular yokes (123, 124) and the through cylindrical cavity for the insertion of the central tubing (122) of the rotor.Note that during the overmolding operation, the wound teeth and the stator yoke are embedded in the plastic resin and the cylindrical cavity passing through the stator is preferentially formed by this resin rather than by the stator yoke. The frame (5) also has a receiving zone (52), on the proximal side of the transverse wall (55), provided for the insertion of the electronic card (401) having the means for controlling the electric motor (100) and the braking means (200). The receiving zones (56, 57) are respectively closed by covers (53, 52) forming the rear and front faces of the device, these covers being preferentially welded to the frame (5) by laser process. The cover (52) of the front face has a passage provided with a seal (9) crossed by the axis (1).

[0050] The braking means (200) consists of two stamped sheets (201, 202) in the form of pierced hats which fit together to form a closed annular cavity, in which two coils (220) are arranged to provide braking. Interposed ferromagnetic annular pieces (205, 206, 207) make it possible to improve the braking looping of the magnetic flux and orienting the direction of this flux as radially as possible in the air gaps (330, 335) containing the magnetorheological fluid, are arranged on either side of the coils (220) in the annular cavity. The braking means (200) therefore has a cartridge-type assembly, by inserting the components one by one in the annular cavity, a first intermediate ferromagnetic part (205) is thus stacked, then a toroidal coil (220) whose wire has been previously wound on a plastic body, then a second intermediate ferromagnetic part (206) which must be thicker than the first to avoid saturation of the magnetic flux between the two coils (220), then the second coil (220) identical to the first, and finally a last intermediate ferromagnetic part (207).This cartridge thus constituted is introduced into the injection mold and the annular cavity of the cartridge is sealed by the injection of plastic material constituting the transverse wall (55).

[0051] When associating the rotor (110) with the stator (120) and the overmolded braking means (200), there remains, to accommodate the magnetorheological fluid, a cavity having a geometry of revolution whose generator is in the shape of a “U”. The legs of this “U” being produced by the air gaps (230, 235) formed between the tubular yokes (123, 124) of the rotor (110) and the brake element (200), and its base being located between the distal end of the braking means (200) and the part of the disc partition (122) located between the two tubular yokes (123, 124). This configuration is advantageous because it gives rise to a receiving cavity opening only on the proximal side.Thus, during the assembly process, the magnetorheological fluid can be poured by a single dosage at the bottom of the groove, formed by the tubular yokes (123, 124) and the disc partition (122), and distributed in the air gaps (230, 235) by piston effect when the braking means (200) is inserted into the groove. The watertight closure of the “U”-shaped cavity is achieved by the arrangement of two concentric O-rings (211, 212) arranged between the disc end of each of the tubular yokes (123, 124) and the transverse wall (55) of the frame (5).

[0052] The motor (100) is in a known manner a topology with radial flux and an external rotor (120), the stator (110) has a generally cylindrical shape, its teeth (112) spreading radially from an internal yoke. The rotor (111) is provided with a tubular yoke (123) carrying on its internal surface a magnetized ring (125) facing the ends of the teeth (112) to form the magnetic air gap (150) of the motor (100). In the example illustrated, the stator is provided with 24 teeth (112) of which one in two carries a coil (111). The internal yoke of the stator (110) is provided with a cylindrical passage to accommodate the axis (1).

[0053] In this embodiment, the position sensor (300) measures the differential position between a stator (330) and a target (320) in the form of a multi-pole ring magnetized. The stator (330) and the target (320) are mechanically linked by a torsionally deformable element, so that the measurement of their differential displacement can provide torque information. The stator (330) is, in a known manner, in particular from patent application FR2972896, provided with two toothed and interdigitated ferromagnetic rings, the number of teeth of each ring being equal to the number of pairs of poles of the multipolar ring, flux collectors also being located on the periphery of the stator to channel the passage of the flux between the two toothed rings, said collectors forming between them an air gap in which the probe (310) is housed. In order to provide differential movement between the stator (330) and the target (320), the rotor axis is in the form of a shaft (10), on which the stator (330) is rigidly fixed at a fixing zone (13) located at the front cover (52).The shaft extends in the distal direction to the rear cover (53) having an intermediate zone of smaller diameter and capable of deforming in torsion in a calibrated manner so as to provide an elastically deformable means (11). This shaft (10) is housed in the tubing (121) of the rotor (120) and is secured by fitting to said tubing at its distal end (132). The rigid tubing extends in the proximal direction to the level near the sensor (300) so as to provide a fixing support for the target (320). The application of a torque to the shaft (10) causes the torsion of the elastically deformable means and therefore a differential displacement between the fixing zone (13) and its distal end (12) to which the tubing is secured.The tubing (121) being rigid, a differential displacement is therefore obtained between the proximal end (131) of the tubing to which the target (320) is secured and the fixing zone (13) to which the stator (330) is secured. In order to correctly guide this differential displacement, a smooth bearing (530) is provided between the inner wall of the distal end of the tubing (121) and the periphery of the shaft (10).

[0054] The probe (310) of the torque sensor (300) is arranged on a second electronic card (420) in radial proximity to the target (320). The electronic card (420) is electrically connected to the main electronic card (410) by means of flexible tracks (430). The electronic cards (410, 420) are produced in a single PCB, the latter being delaminated locally to leave only the flexible tracks (430), thus obtaining relative positioning freedom for the two electronic cards while ensuring their electrical connection for the transmission of the signals from the position sensor (300).

[0055] Optionally, the electrical signal provided by the torque sensor (300) is processed to determine the presence of the driver's hands on the steering wheel. This processing consists of analyzing the electrical signal delivered by the sensor with sampling at a high frequency, typically more than 16Khz, to characterize the signature of the signal during hand positioning, resulting in particular in a transient peak of angular resetting, followed by a sequence with a limited noise level. This characterization can be carried out after modeling or by a component providing artificial intelligence processing through a supervised learning process.

[0056] For the embodiment shown in Figures 4 and 5, the brake device has a response time greater than that of the motor for the same supply voltage. This is essentially linked to the difference in permeance between the magnetic circuits of the motor and the brake device. Disparities in response time can be noted that can be up to a factor of 20 and are optimally located around a factor of 8. In order to improve the responsiveness of the brake device, the electronic circuit can integrate a voltage converter, commonly called a boost converter, making it possible to provide a voltage greater than the supply voltage of the electronic card. This makes it possible to control the brake device with a voltage greater than the supply voltage of the motor, leading to a reduction in the response time of the brake device.

Claims

Claims

1. Haptic control device comprising - an electric motor (100) provided with a stator (110) comprising a plurality of wound teeth (112), said teeth (112) extending radially from an annular yoke and an external rotor (120) comprising a plurality of magnetized magnetic poles arranged on the internal surface of a ferromagnetic tubular yoke (123) and facing the end of the wound teeth (112) to form a magnetic air gap (230), - a user interface (2) mechanically connected to said rotor (120) - an electronic card (400) comprising the means for controlling said electric motor,- an angular position sensor (300) providing the position of said user interface (2) - a braking means (200) characterized in that - said braking means (200) acts directly on at least one external tubular surface (250) of said tubular yoke (123) of the rotor (120) of the motor (100) - in that it comprises a computer controlling on the one hand said electric motor (100) and on the other hand said braking means (200) as a function of the signal delivered by said angular position sensor and a control law.,

2. Haptic control device according to claim 1 characterized in that it further comprises an elastically deformable element (11), said position sensor (300) comprising two members secured to each of the ends of said elastically deformable element (11) to provide a signal of the relative angular position of these two members.

3. Haptic control device according to claim 2 characterized in that one of the members is composed of interdigitated toothed crowns, the other of said members being a multipolar magnetic ring, said sensor (300) further comprising flux collectors making it possible to guide the magnetic flux between the toothed crowns, said collectors forming between them an air gap in which a magneto-sensitive probe (310) is housed.

4. Haptic control device according to claim 1 characterized in that said rotor (120) has at least one second ferromagnetic tubular yoke (124) defining an additional braking interaction surface, said braking means (200) acting directly on the outer surface (250) of said first tubular yoke (123) of the rotor (120) of the motor (100) and on at least one inner surface (260) of said tubular yoke (124).

5. Haptic control device according to the preceding claim, characterized in that the electrical connection (403) between said motor and said position sensor (300) is made by a locally delaminated printed circuit (420).

6. Haptic control device according to claim 2 characterized in that the electronic card (400) also comprises the means for controlling the braking means (200).

7. Haptic control device according to the preceding claim, characterized in that said braking means has a nominal response time at least eight times greater than the nominal response time [i.e. at identical supply voltage] of said motor.

8. Haptic control device according to the preceding claim characterized in that said electronic card (400) comprises a voltage converter for supplying said braking system with a voltage higher than the supply voltage of said motor.

9. Haptic control device according to claim 2 characterized in that it comprises a means for detecting the presence of hands on a steering wheel constituted by said position sensor (300) and a calculator applying a function taking into account at least one derivative of the position signal.

10. Haptic control device according to claim 1 characterized in that said braking means (200) is constituted by at least one electrically actuated friction element movable between a position spaced from said rotor yoke (120) and a position of tribological interaction with said yoke.

11. Haptic control device according to claim 1 characterized in that said braking system consists of a hysteresis brake magnetic.

12. Haptic control device according to claim 1 characterized in that the brake device is provided with an annular ferromagnetic core cooperating with at least one electric coil (220) and arranged concentrically with said electric motor, said ferromagnetic core forming with the ferromagnetic yoke of the rotor a second air gap (235) in which a magnetorheological material is arranged.

13. Haptic control device according to the preceding claim characterized in that said magnetorheological material is a magnetorheological fluid (210) accompanied by a sealing means.

14. Haptic feedback steering wheel characterized in that it comprises a haptic control device according to claim 1 characterized in that the motor (100) and the brake device (200) are integrated in a housing, the electronic card (400) being integrated into a central control unit located outside said housing.

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