Enhanced haptic control device

Abstract

The present invention relates to a haptic control device comprising an electric motor (100) equipped with a stator (110) having a plurality of wound teeth (112), said teeth (112) radiating outwards from an annular yoke and an external rotor (120) having 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), a braking means (200). This braking means (200) acts directly on at least one external tubular surface (250) of said tubular cylinder head (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 according to the signal delivered by said angular position sensor and a control law.Figure from the summary: Figure 1.

Description

Title of the invention: Enhanced haptic control device Technical field of the invention

[0001] The invention relates to a haptic control device for a rotating organ, typically a steering wheel or handlebar of a vehicle, or a control wheel of industrial equipment, a joystick or yoke / half-wheel (in English “yoke”) for guidance, or 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 efforts exerted on the controlled organ, which could be masked by assistance exceeding the efforts exerted voluntarily by the user.

[0003] It is also useful to be able to brake the rotation of a steering wheel in certain specific situations, for example, when the wheels come to a stop against a curb, to clearly make the driver aware of this situation, or when a disabled or intoxicated driver uses the steering wheel for support to help themselves get out of the vehicle. It is then important that the steering wheel be held firmly to allow the driver to use it for support to maintain their balance. Another context concerns limiting the angular travel of rotation, without a mechanical stop, to prevent the steering wheel from being turned over several times, which could lead to the airbag wires being torn out of the steering wheel. Also, when driving on the highway, it can be useful to strongly brake the steering wheel rotation to prevent skidding. prior art

[0004] Prior art patent application WO2022123088Al is known, which relates to a haptic control device equipped with a magnetorheological braking system comprising a fixed support and two braking components. One of the two braking components is rotationally fixed to the support. The two braking components can rotate continuously relative to each other 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 envelope portion extending around the first braking component. Peripheral braking gaps, axially spaced and at least partially 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 makes contact with 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 a force feedback electronic control system that is configured to drive the brake and clutch, during use, so as to provide haptic feedback to the user.

[0006] The 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 suitable system 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 movement relation between the means of contact and the body;

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

[0012] Prior art solutions involve a combination of two coupled electromagnetic systems: an electric motor and a braking system, generally magnetorheological, which act on the user interaction device. These solutions are relatively bulky, and the mechanical coupling between the braking system and the motor introduces latencies and artifacts that reduce the dynamics of the haptic system. Furthermore, magnetorheological braking exhibits hysteresis, limiting the responsiveness of the haptic system and preventing the reproduction of faithful feedback with sufficient resolution. Description of the invention

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

[0014] To this end, the present invention proposes a haptic control device comprising - an electric motor equipped with a stator having a plurality of wound teeth, said teeth radiating radially from an annular yoke and an external rotor having a plurality of magnetic poles magnets arranged on the internal surface of a ferromagnetic tubular cylinder head and facing the ends of the wound teeth to form a magnetic air gap, - a user interface mechanically linked to the rotor - an electronic circuit board containing the means for controlling said electric motor - an angular position sensor providing the position of said user interface - a braking system characterized in that - said braking means acts directly on at least one external tubular surface of said tubular cylinder head of the motor rotor - in that it includes a computer controlling on the one hand said electric motor and on the other hand said braking means according to the signal delivered by said angular position sensor and a control law. Depending on the variants: • The device also includes an elastically deformable element • said position sensor comprising two organs attached to each end of said elastically deformable element (to provide a signal of the relative angular position of these two organs. • one of the organs is composed of interdigitated toothed rings, the other of said organs being a multipolar magnetic ring, said sensor further comprising flux collectors enabling the magnetic flux to be guided between the toothed rings, said collectors forming between them an air gap in which a magnetosensitive probe is housed. • said rotor has at least one second ferromagnetic tubular endplate defining an additional braking interaction surface, said braking means acting directly on the outer surface of said first tubular endplate of the motor rotor and on at least one inner surface of said tubular endplate • the electrical connection between said motor and said position sensor is made by a locally delaminated printed circuit board. • The electronic board 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 board includes a voltage converter to power said braking system with a voltage higher than the supply voltage of said motor. • The device includes a means for detecting the presence of hands on a steering wheel, consisting of said position sensor and a computer applying a function that takes 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 away from said rotor cylinder head and a position of tribological interaction with said cylinder head. • said braking system consists of a magnetic hysteresis brake. • the braking 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 disposed. • said magnetorheological material is a magnetorheological fluid accompanied by a sealing means. • The motor and braking device are integrated into a housing, with the electronic board integrated into a central control unit located outside said housing. brief description of the figures

[0015] Other features and advantages of the invention will become apparent from the following detailed embodiments, with reference to the accompanying figures which respectively represent:

[0016] [Fig-1] Fig. 1 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 implementation of a haptic device according to the invention

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

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

[0020] [Fig. 5] [Fig. 5] represents a schematic view of a second example of a implementation 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 situations of low amplitude and low power movements and for situations involving sionnelles of arrival at the end stop with high torques. The principle of the invention consists of combining, in a single compact device, a. an engine, providing high dynamic displacements, 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 part.

[0022] This signal consists either of an angular position signal, or of a differential angular position signal of two parts of a segment of a torsion shaft, or of a torque signal exerted on a segment of a torsion shaft determined according to 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 computer can be integrated into the device or remote; in particular, it could be integrated into the central control electronics of a motor vehicle. The computer optionally receives other contextual input signals.

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

[0025] The braking means consists, but is not limited to: - 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 via 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 an intermediate part with the cylinder head of the engine in order to reduce bulk and avoid any assembly of parts that could distort the mechanical interaction between the braking means and the electric motor, and in order to ensure that the control controlled by the computer does not suffer any mechanical artifacts when applied to the engine and the braking means.

[0027] Optionally, some 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 board integrated into the haptic device. This electronic board may also include the brake control means.

[0028] Also optionally, the electronic board has a voltage converter allowing the braking system to be supplied with a voltage different from that of the electric motor. Detailed description of a general example

[0029] Fig. 1 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 element consisting of a shaft (1) coupled to a user interface, for example a flywheel (2), and a driven element (3) consisting of the rotor (120) of the electric motor (100), fixed to the shaft (1) and concentric with the stator (110).

[0031] The motor (100) is an external rotor motor (120) surrounding the stator (110), to define in a known manner a tubular air gap (150). The rotor (120) has 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 has a plurality of teeth (112) extending radially in the direction of the rotor (120). Some or all of the teeth (112) carry electrical coils (111).

[0033] The stator (110) is fixed to the frame (5). One or more bearings (510, 520) provide guidance for the shaft (1) relative to the frame (5). These bearings (510, 520) can be plain bearings, roller bearings, or any other means of guidance 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 finish 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 board (400) is arranged, in the example described without limitation, transversely; it is traversed by the shaft (1). The electric coils (111) of the motor as well as the braking means (200) are electrically connected to this printed circuit board (400) by electrical connections (401, 402).

[0037] To ensure the braking of the rotor (120), the activation of the braking means (200) attached 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 implementation

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

[0040] In this embodiment, the electronic circuit comprises two printed circuit boards (410, 420) connected by a flexible ribbon cable (430). The first printed circuit board (410) contains the electronic components for controlling the motor and the braking system (200). The second printed circuit board (420), positioned in a plane parallel to that of the first printed circuit board (410), supports the sensor (310). The flexible ribbon cable (430) can be made in various ways, either by using a ribbon cable connected to each PCB by a connector, or by a technique of delaminating the resin layers of a PCB to create the ribbon cable directly within the internal copper layer of that PCB, or by any other method known to those skilled in the art. The aim is to ensure the connection of two electronic boards 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 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) consists of 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 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] Figure 3 shows 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). To this end, the rotor (120) has a tubular yoke (124) in which the braking means (200) is housed. The braking means (200) has a tubular configuration and acts on the two inner and outer tubular surfaces of the rotor (120). In the case of magnetorheological braking, the magnetorheological fluid is activated by excitation coils.

[0045] DETAILED VIEW OF ANOTHER EXAMPLE OF THE INVENTION

[0046] Figures 4 and 5 show different views of a device according to the invention, [Fig. 4] showing an axial view and [Fig. 5] an exploded perspective view of this device. It comprises a magnetorheological braking means (200), exploiting the modification of the viscosity of a magnetorheological fluid by means of electrical coils (220), the magnetorheological fluid being disposed in contact with the rotor (110) and the modification of its viscosity resulting in a modulation of the friction forces on the rotor (110).

[0047] The electric motor (100) and the braking means (200) are arranged concentrically, with 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) containing 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 cylinder head (123) so as to control its movement as precisely as possible.To increase the braking capacity of the associated means, the rotor (120) is equipped 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 thus acts 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 braking means (200) being housed between these two bells and exerting a magnetic braking force on each of them, and the cylindrical stator (110) being housed within the inner bell formed by the inner tubular yoke (123).

[0048] The tubular cylinder heads (123, 124) are connected at their distal end, the end opposite the coupling zone (10) of the shaft (1) with the driven element, to a disc partition (122). Said disc partition (122) radiates from a tube (121) allowing the rotational guidance of the rotor (120). Said tube (121) is concentric with the tubular cylinder heads (123, 124) and extends in the same direction, these 3 elements thus being joined together at their distal end and left free at their proximal end, the one 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 the level of 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 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), ensure the guidance of the rotor (120).

[0049] The frame (5) is produced by plastic molding. Its manufacture consists of precisely positioning the stator (110) and the braking means (200) in the injection mold and overmolding them, 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 area (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 are positioned, while leaving free the areas necessary for the insertion of the rotor, namely an annular space between the stator and the braking means and an annular space around the periphery of the braking means to accommodate the tubular yokes (123, 124) and the cylindrical through cavity for the insertion of the central tube (122) of the rotor.It should be noted 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 mounting area (52) on the proximal side of the transverse wall (55), designed for the insertion of the electronic board (401) containing the control means for the electric motor (100) and the braking means (200). The mounting areas (56, 57) are respectively closed by covers (53, 52) forming the rear and front faces of the device, these covers being preferably welded to the frame (5) by laser process. The cover (52) on the front face has a passage fitted with a sealing gasket (9) through which the shaft (1) passes.

[0050] The braking means (200) consists of two stamped, perforated, cap-shaped plates (201, 202) that fit together to form a closed annular cavity, in which two coils (220) providing the braking are arranged. Intercalated ferromagnetic annular pieces (205, 206, 207) improve the re The magnetic flux loop and the direction of this flux are oriented as radially as possible in the air gaps (330, 335) containing the magnetorheological fluid. These elements are arranged on either side of the coils (220) in the annular cavity. The braking means (200) thus has a cartridge-type assembly. By inserting the components one by one into the annular cavity, a first ferromagnetic interlayer (205) is stacked, followed by a toroidal coil (220) whose wire has been previously wound on a plastic body, then a second ferromagnetic interlayer (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 ferromagnetic interlayer (207).This cartridge, thus formed, 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 the rotor (110) is joined with the stator (120) and the overmolded braking element (200), a cavity with a geometry of revolution remains, the generatrix of which is U-shaped, to accommodate the magnetorheological fluid. The legs of this U are formed by the air gaps (230, 235) created between the tubular end plates (123, 124) of the rotor (110) and the braking element (200), and its base is located between the distal end of the braking element (200) and the portion of the disc partition (122) situated between the two tubular end plates (123, 124). This configuration is advantageous because it results in a receiving cavity that opens only on the proximal side.Thus, during the assembly process, the magnetorheological fluid can be poured in a single dose at the bottom of the groove, formed by the tubular cylinder heads (123, 124) and the disc partition (122), and distributed into the air gaps (230, 235) by piston effect when the braking element (200) is inserted into the groove. The U-shaped cavity is sealed by two concentric O-rings (211, 212) positioned between the disc end of each of the tubular cylinder heads (123, 124) and the transverse wall (55) of the frame (5).

[0052] The motor (100) is, in a known manner, a radial flux topology with an external rotor (120). The stator (110) has a generally cylindrical shape, its teeth (112) radiating radially from an inner yoke. The rotor (111) is provided with a tubular yoke (123) carrying on its inner 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 illustrated example, the stator has 24 teeth (112), every other tooth of which carries a coil (111). The inner yoke of the stator (110) is provided with a cylindrical passage to accommodate the shaft (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 multipolar 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, as is known, notably from patent application FR2972896, equipped with two toothed and interdigitated ferromagnetic rings, the number of teeth on each ring being equal to the number of pole pairs of the multipole ring, flux collectors also being located on the periphery of the stator to channel the passage of 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 a differential displacement between the stator (330) and the target (320), the axis of the rotor is in the form of a shaft (10), on which the stator (330) is rigidly fixed at the level of a fixing area (13) located at the level of the front cover (52).The shaft extends distally to the rear cover (53), featuring an intermediate zone of smaller diameter capable of calibrated torsional deformation to provide an elastically deformable means (11). This shaft (10) is housed within the tubing (121) of the rotor (120) and is secured to said tubing at its distal end (132) by a press fit. The rigid tubing extends proximally to the vicinity of the sensor (300) to provide a mounting surface for the target (320). Applying a torque to the shaft (10) causes torsion of the elastically deformable means, resulting in a differential displacement between the mounting zone (13) and its distal end (12), to which the tubing is attached.Since the tubing (121) is rigid, a differential displacement is obtained between the proximal end (131) of the tubing to which the target (320) is attached and the fixing zone (13) to which the stator (330) is attached. In order to correctly guide this differential displacement, a plain 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 located on a second electronic board (420) in radial proximity to the target (320). The electronic board (420) is electrically connected to the main electronic board (410) by means of flexible traces (430). The electronic boards (410, 420) are fabricated on a single PCB, which is locally delaminated to leave only the flexible traces (430). This provides relative freedom of positioning for the two electronic boards while ensuring their electrical connection for the transmission of 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 above 16 kHz, to characterize the The signal signature during hand positioning is characterized by a transient angular registration peak, followed by a sequence with a limited noise level. This characterization can be performed after modeling or by a component providing artificial intelligence processing through a supervised learning process.

[0056] In the embodiment shown in Figures 4 and 5, the brake device exhibits a longer response time than the motor for the same supply voltage. This is primarily due to the difference in permeance between the magnetic circuits of the motor and the brake device. Response time disparities of up to a factor of 20 are observed, with the optimal ratio being around a factor of 8. To improve the responsiveness of the brake device, the electronic circuit can incorporate a voltage converter, commonly called a boost converter, which provides a voltage higher than the supply voltage of the electronic board. This allows the brake device to be driven with a voltage higher than the motor's supply voltage, leading to a reduction in the brake device's response time.

Claims

Demands

1. Haptic control device comprising - an electric motor (100) equipped with a stator (110) having a plurality of wound teeth (112), said teeth (112) radiating outwards from an annular yoke and an external rotor (120) having 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 board (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 cylinder head (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) according to 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 attached to each end 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 elements is composed of interdigitated toothed rings, the other of said elements being a multipolar magnetic ring, said sensor (300) further comprising flux collectors for guiding the magnetic flux between the toothed rings, said collectors forming between them an air gap in which is housed a magnetosensitive probe (310).

4. Haptic control device according to claim 1 characterized in that said rotor (120) has at least one second ferromagnetic tubular cylinder head (124) defining an additional braking interaction surface, said braking means (200) acting directly on the outer surface (250) of said first tubular cylinder head (123) of the rotor (120) of the motor (100) and on at least one inner surface (260) of said tubular cylinder head (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 board (420).

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

7. Haptic control device according to the preceding claim characterized 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 board (400) includes 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 consisting of said position sensor (300) and a computer 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) consists of at least one electrically actuated friction element movable between a position away from said rotor head (120) and a tri-bological interaction position with said head.

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 disposed.

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 board (400) being integrated into a central control unit located outside said housing.

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