A device for generating haptic simulations of musical instruments

Abstract

The present invention relates to a haptic device (1) for controlling the keys of a keyboard equipped on an electronic musical instrument, associated with a key (K) pivotally mounted with respect to a frame, the key extending in a longitudinal direction and undergoing angular movement between a high angle position and a low angle position, characterized in that the haptic device (1) comprises means (30) for detecting a dynamic state of the key, calculation means for calculating, depending on the dynamic information, an instantaneous resistance force to be applied to the key in response to a depression of the key, a rotary electric actuator (10), and mechanical coupling means (20) arranged between the actuator and the key to apply a resistance force to the key, the mechanical coupling comprising at least one element that bends under pressure and hardens under traction.

Description

Detailed Description of the Invention

[0001] [Technical field] The present invention relates to a device for the haptic simulation or emulation of a digital keyboard-based musical instrument.

[0002] More particularly, the present invention relates to a device and associated method for recreating the tactile sensation of an acoustic piano keyboard on an electronic piano. [Background technology]

[0003] Designers and manufacturers of digital pianos have been trying for years to improve the sense of touch in order to approach the feeling of an acoustic piano by providing haptic effects closer to the original. Therefore, the problem is to reproduce the "force feedback" exerted by the parts of the mechanism of an acoustic piano key (bridge, jack, whippen, hammer, muffler) on the keys of a digital piano keyboard.

[0004] A conventional acoustic piano is designed to have a certain resistance to the touch and a certain return speed of the keys in order to work accurately and provide a good playing sensation. When tuning a piano keyboard, the descending and ascending key weights are looked at and weights may be added to optimally tune these values. The balance of the feel also depends on the inertia of the mechanism. This depends on the mass of the parts, mainly the hammers and weights, as well as the mechanical whippen. More specifically, it can be said that the inertia depends on the mechanical ratio between the hammer stroke and the key stroke. Finally, many other effects, namely the stiffness of the connecting felt between the parts, the internal friction on the felt, the dry friction on the contact points and at the pivots, are also nonlinear (in the mathematical sense) and sometimes irregular, and they affect the quality of the feel. Finally, the relationship between the "force feedback" of the key and its movement arises from a dynamic range with several degrees of freedom, which is nonlinear, irregular and depends on the history of the movement. It cannot be accurately described by an impedance type relationship.

[0005] From 1928, on the Ondes Martenot instruments it was possible to find keys called "intensity keys" or expression keys, which allow to control the volume of the sound produced by the instrument. The keys are mounted in the form of levers so that by pressing the key, one crushes a bag of conductive powder that transmits the electric signal that carries the sound. The crushing of the bag leads to a modification of the resistivity of the powder and, consequently, to a modification of the amplitude of the sound. The use of such bags allows a relationship between the force applied to the key and the amplitude of the sound, which is very close to the psychophysiological perception by the player.

[0006] US9275618 returns to this principle by improving it. The tail of the key is fixed at its end to a flexible metal strip, which is clamped to pivot the key. A force and / or position sensor is placed on the key. A deformable stop (an elastomeric material) placed under the tail of the key exerts a force resisting the downward movement exerted by the user. The asymmetrical hole of this stop gives a monotonic nonlinear characteristic to the resistance force exerted by the stop. The sensor recovers the information of the resistance force resulting from the movement of the flexible strip and the deformable stop in the form of a signal, which is then fed to a processing unit to generate a sound having a volume corresponding to the stimulus.

[0007] French patent application FR 2 902 538 describes a haptic simulation device that uses a magnetorheological fluid whose viscosity is modulated by a magnetic field to generate a force that opposes the movement of the key to improve the sensation of the player. The keyboard instrument disclosed in this document uses three sensors (acceleration, velocity and position) arranged to provide in real time a current control to a means for generating a magnetic field as a function of time, which opposes a reaction force that depends on the displacement of the key to provide a satisfying sensation of touch. The generating means consist of a coil covered by a current that varies over time, which makes it possible to activate a force on a strip fixed to the key whose intensity varies as a function of the value of the current.

[0008] WO 2020 / 016536 describes a haptic controller capable of reproducing certain sounds other than those of a traditional piano, one of these features being generally designated by the term "aftertouch", the essential element of which is a damping device consisting of a body made of a deformable material having two recesses, the body having a protrusion arranged in a groove located on the bottom surface of the key. The two recesses absorb the compression exerted by the key through the protrusion along two different damping profiles, one flexible and the other rigid. A sensor adapted to measure the rotational and translational displacement of the key delivers a signal as a function of this displacement.

[0009] US Patent No. 7,582,821 discloses a device that seeks to reproduce the sensation of releasing an acoustic piano key, essentially consisting of a pivoting lever, three key switches and a retractable load member. When the player presses a key, the key pivots about its axis and presses a pivoting lever located below the key with substantially the same length as the key. The pivoting lever then contacts three elastic switches of different lengths, making it possible to provide information about the depth of the press thanks to the successive triggering sequence of the switches. The retractable load member slows down the rise of the lever according to the information collected by the switches and the position sensor.

[0010] In US2018286605, the reaction force generating device consists of a deformable element in the form of a tilted dome with a flat surface at its apex, the tilt of which allows it to stably receive the key that applies pressure.

[0011] Finally, in the document "Realisation d'un dispositif a retour d'effort to simulate the touch of various mechanisms for playing pianos", Guillaume Paillot, Quentin Desclee (2018), a force feedback device is proposed, which consists of an actuator placed in the key's movement (contact area between the key and the striking mechanism), two fixed permanent magnets and a coil integral with the key. This embodiment poses stability problems due to the mass and inertia that this configuration gives, which are stronger than those of a conventional key.

[0012] However, these devices are bulky due to the available space and / or expensive and / or do not allow to actively reproduce fully the dynamics of a given key (e.g. an acoustic piano) without using more expensive mechanisms at the origin of this dynamics, or derived mechanisms that are unsatisfactory in terms of the user's ability to control the instrument. OBJECTS OF THEINVENTION

[0013] To this end, according to a first aspect, the invention proposes a tactile device for controlling the keys of a keyboard equipped on an electronic musical instrument intended to reproduce the sensation of using a similar acoustic musical instrument, the tactile device being arranged to be associated with the keys of the electronic musical instrument pivotally mounted around a pivot axis relative to a frame, the keys extending in the longitudinal direction and having an angular displacement between a high angle position called the original position and a low angle position called the stop.

[0014] This device is a detection means for detecting dynamic state information of the key; a calculation means for calculating the instantaneous resistance force applied to the key in response to depression of the key as a function of the dynamic information thus detected; a rotary electric actuator arranged to generate a resistive force; and a mechanical coupling means disposed between the rotary electric actuator and the key for applying a resistive force to the key, the mechanical coupling means comprising at least one element that flexes under pressure and stiffens under traction.

[0015] The device according to the invention proposes a compact and inexpensive construction that allows to reproduce the sensation of using an acoustic musical instrument, for example a piano, while having little or no inertia in its actuation and little or no instability in its control. It allows to select or set the resistance to a given key press. In addition, it allows to apply a dynamic reaction force upon the key press according to a given dynamic relationship, including implementing several internal degrees of freedom. Finally, it tends to return the key to its original position when the user stops pressing it.

[0016] For the remainder of the above and / or description, the following terms have the following definitions: Key: A manual control member arranged to control the emission of sound when depressed by a playing user.

[0017] Rotary Electric Actuator: A rotating electromagnetic device or actuator. Distal end of the key: the pressure zone or end zone intended to receive the user's finger(s). Proximal End: The end of a key opposite the distal end. Key Return: A part that protrudes from the underside or bottom of a key such that one face of the key return faces the underside or bottom of the key; for example, the key return is "L" shaped and one face of the base of the "L" shaped key return faces the underside or bottom of the key. Mechanical coupling means: a means for connecting an actuator to a key, which may comprise one or more interconnected mechanical elements. Unidirectionally flexible element of the mechanical connection means: a means that can bend in particular in one dimension or direction (zero flexibility in two stress directions) without longitudinal elasticity and / or limited flexibility (wires generally have a very large flexibility). Element that flexes under pressure and stiffens under traction: a flexible element arranged to work under tension both to convert a resistive mechanical torque into a resistive force applied to the point on the key being depressed and to return the key to its angular rest position. Termination: the end of a mechanical connection means such as an actuator termination or a key termination, and / or the end of a flexible element, for example a cable termination or a ribbon termination. High angle position or original position: the position in which the key is placed on the upper abutment before the user starts to actuate the key to obtain a sound when playing the instrument normally. Ribbon: An element having a width at least three times greater than its thickness, e.g. a thin strip-shaped sheet made of metal or fiber or composite polymer, capable of bending without any longitudinal or transverse elasticity other than that which allows it to bend or curve, and having a low but not negligible resistance to bending or rolling. Cable: A cable or a parallel combination of several cables (e.g., 2 to 5 cables) that can bend in two directions but has no elasticity in the longitudinal direction.

[0018] Preferably, the pivot axis of the key is located at the proximal end of the key.

[0019] Preferably, the mechanical coupling means is arranged between the actuator and the key. The mechanical coupling means comprises an actuator end and a key end. According to one embodiment, the mechanical coupling means comprises a single key end and a single actuator end.

[0020] Preferably, the key end is attached to the key at a key point, called the fastening point, located between the receiving point, located at a distance equal to at least 25% of the longitudinal length of the key from the pivot axis, on the one hand, and the distal end of the key, on the other hand. In other words, the key points can be located on a continuous area extending from the distal end of the key over a distance equal to 75% of the longitudinal length of the key.

[0021] The function of the actuator and the mechanical connection between it and the key consists of physically applying a force to the key, the force being specified or its relationship to the movement of the key being predetermined. Depending on the fastening point on the key, the torque applied to the key by the actuator is calculated as a maximum of about 20 Newtons multiplied by the lever arm at the distal end at the fortissimo mark.

[0022] According to a first embodiment, the rotary electric actuator has an axis of rotation parallel to the pivot axis of the key.

[0023] According to a second embodiment, the rotary electric actuator has an axis of rotation parallel to the longitudinal direction of the key.

[0024] According to a third embodiment, the rotary electric actuator has an axis of rotation perpendicular to the longitudinal direction of the key and to the axis of rotation of the key.

[0025] The position where the rotation axis of the actuator is parallel or perpendicular to the longitudinal direction of the key is understood to be the position established when the key is at rest or in its original position, and the key can pivot a few degrees when pressed by the user. In other words, the rotation axis of the actuator and the longitudinal direction of the key are substantially parallel or substantially perpendicular (plus or minus a few degrees) and are located in the same vertical plane.

[0026] Preferably, the rotary electric actuator is a DC electric motor.

[0027] Advantageously, the rotary electric actuator is located above or below the key, the arrangement of the actuator and mechanical linkage being arranged to apply a traction force to the instrument key, providing a resistance to depression when the user presses the key, and returning the key to its original position when the user is not pressing the key.

[0028] Advantageously, the mechanical coupling means is located above or below the key. Preferably, the mechanical coupling means comprises a key end of the mechanical coupling means attached to the top or bottom surface of the key.

[0029] The upper surface is understood to mean the surface that faces upwards when the electronic musical instrument is placed horizontally and / or the surface that faces towards the outside of the instrument, and the lower surface is understood to mean the surface that faces downwards when the electronic musical instrument is placed horizontally and / or the surface that faces towards the inside of the instrument.

[0030] The mechanical coupling means comprises means for connecting with the key, the connecting means being attached to the key and arranged to connect the key end of the mechanical coupling means to the key.

[0031] The mechanical coupling means comprises at least one connecting piece corresponding to the key end. Preferably, the connecting piece is located as far as possible from the pivot axis of the key. This distance makes it possible to apply a larger resistive torque to the key and / or to choose an actuator within the range of devices with a lower nominal current or lower power, reducing the price and / or inertia of the motor and / or the price of its electrical control.

[0032] For example, the ratio between, on the one hand, the lever arm distance separating the pivot axis from the key point where the key end of the mechanical coupling means is attached to the key, and, on the other hand, the lever arm distance separating the rotation axis of the rotary electric actuator from the actuator point where the actuator end of the mechanical coupling means is attached to the actuator shaft, is at least 10, preferably at least 20, advantageously at least 30, advantageously at least 40, advantageously at least 50.

[0033] According to one alternative embodiment, the rotary electric actuator is positioned under the key, for example on the key return, which is attached or positioned on the underside of the key, for example in a flat piano.

[0034] Preferably, the key end of the mechanical coupling means is attached to an upper surface of the key return of the key. The mechanical coupling means comprises a connecting piece arranged on the upper surface of the key return.

[0035] Advantageously, the rotary electric actuator has a diameter or width that is less than the average width of the key.Preferably, the rotary electric actuator has a diameter or width that is less than twice the average width of the key.

[0036] It may also have a longitudinally elongated shape, correspondingly increasing the length of the conductor and therefore the torque available for a given current in the actuator.

[0037] According to one embodiment, the mechanical coupling means comprises an assembly means comprising a winding part arranged to fit onto the shaft of the rotary electric actuator and a stirrup-shaped clamp part having two prongs arranged to at least partially surround the winding part.

[0038] Preferably, the at least one flexible element is unidirectionally flexible, for example the at least one unidirectionally flexible element comprises one or more ribbons or one or more cables.

[0039] Firstly, the slight bending of the flexible element in a single direction serves to at least partially guarantee the kinematic compatibility between the rotational movement of the key and the translational movement imposed by the traction of the actuator. The flexibility of the element allows it to wind around the actuator axis. If the mechanical linking means comprises two unidirectional flexible elements, in particular two ribbons, the kinematic compatibility between the rotational movement of the key and the actuator is performed by one ribbon, called the key ribbon, and the winding around the actuator axis is performed by a ribbon, called the actuator ribbon, separate from the key ribbon, the two ribbons being connected to each other.

[0040] Secondly, the reduced flexibility (not infinite as in the case of a wire) serves to prevent the actuator from continuing to rotate when the key is blocked or slowed in its movement by, for example, a lower stop. The bounces are limited in number and duration by a very specific shape of the longitudinal compressibility of the flexible element in one direction, being zero at the buckling limit and then finite beyond the buckling limit.

[0041] Preferably, the mechanical linkage means comprises at least one ribbon or at least one cable that bends under pressure and stiffens under traction, having a distal end connected to the hub of the rotary electric actuator and a proximal end connected to the key, the ribbon being: (i) converting the resistive mechanical torque into a resistive force applied at the point where the key is depressed; (ii) It is arranged to work under tension both to return the key to its angular rest position and to return the key to its angular rest position.

[0042] At least one ribbon allows the necessary tension to be exerted on the key, while at the same time allowing a slight flexion that is used to ensure compatibility between the rotational movement of the key and the translational movement of the ribbon as it is pulled by the actuator. In addition, the finite flexibility of the ribbon used prevents or eliminates bouncing vibrations when the key reaches the end of its stroke.

[0043] Preferably, the at least one element that bends under pressure and hardens under traction comprises a cable that bends under pressure and hardens under traction or a ribbon that bends under pressure and hardens under traction.

[0044] According to one embodiment, the mechanical connection means comprises at least two ribbons that bend under pressure and stiffen under traction.

[0045] According to another embodiment, the mechanical connection means comprises at least two cables that bend under pressure and stiffen under traction.

[0046] According to yet another embodiment, the mechanical connection means comprises at least one ribbon that bends under pressure and hardens under traction, and at least one cable that bends under pressure and hardens under traction.

[0047] According to yet another embodiment, the mechanical interlocking means comprises at least three ribbons that bend under pressure and stiffen under traction.

[0048] According to one embodiment, the mechanical connection means comprises a single ribbon having an actuator end arranged to be connected to the actuator shaft and a key end opposite the actuator end arranged to be connected to the key.

[0049] According to one embodiment, the connection means forms a pivot connection between the key and the key end.

[0050] For example, the key end of the mechanical coupling means has a cylindrical opening and the connecting means comprises a pivot shaft, the cylindrical opening being able to engage and pivot about the pivot shaft. Preferably, the connecting means comprises a removable pivot shaft, also called a connecting shaft, and a body having a hole arranged to receive the removable pivot shaft, the body being arranged to be attached to the key and comprising a slot along a plane transverse to the axis of the hole for aligning the cylindrical opening of the key end of the mechanical coupling means with the hole and inserting the removable shaft into the hole and the opening.

[0051] According to one alternative embodiment, the hole has the shape of an oblong hole according to its cross section so as to allow the connecting shaft to translate laterally, preferably with a maximum length of the oblong hole being at least 20% greater than its width (or minimum length).

[0052] According to another embodiment, the mechanical connecting means comprises at least two elements that bend under pressure and harden under traction, the at least two ribbons that bend under pressure and harden under traction, and a joining part arranged between the two ribbons, the joining part having two ribbon receiving surfaces that are opposite and perpendicular to each other for receiving the terminal ends of the two ribbons.

[0053] For example, the mechanical coupling means may comprise two ribbons, namely an actuator ribbon arranged to be connected to the actuator shaft and a key ribbon arranged to be connected to the key, and a joint piece arranged between the two ribbons and adapted to receive the terminal ends of the orthogonally arranged ribbons.

[0054] According to a particular embodiment, the mechanical connection means comprises three flexible elements, two flexible actuator elements arranged to be connected to the actuator shaft, a flexible key element arranged to be connected to the key, and an interface part arranged between the key element and the two flexible actuator elements, the interface part being arranged to receive the terminal ends of the three ribbons. Preferably, the two flexible actuator elements are connected around the actuator shaft at two diametrically opposed points.

[0055] Preferably, the interface piece has two opposing perpendicular ribbon receiving surfaces for receiving the two ribbons.

[0056] According to one embodiment, the joining part has two mutually opposite and perpendicular slits for receiving the two ribbons so as to be located between them, each slot having a thickness equal to or greater than the thickness of one ribbon.

[0057] According to another embodiment, the joining part comprises two joining parts arranged perpendicular to each other, each joining part having a receiving surface for fastening the ribbon. For example, the joining part comprises two plates extending in the same vertical direction. The plates are arranged perpendicular to each other, each plate being perforated to receive a means for fastening the ribbon.

[0058] Therefore, it is advantageous to use ribbons with increased center thickness relative to the thickness near the joining parts, or shorter ribbons, to increase the buckling limit and decrease the compressibility beyond the buckling limit. Preferably, the center thickness is increased relative to the thickness of the portion of the ribbon that is not wrapped on the actuator shaft.

[0059] According to an alternative embodiment, which may be combined with one or more ribbons or cables, the mechanical coupling means comprises a return component.

[0060] Preferably, the mechanical coupling means comprises at least two flexible elements, a flexible actuator element arranged to be connected to the actuator shaft, a flexible key element arranged to be connected to the key, and a return part having a pivot axis, the return part being arranged between the two flexible elements, the return part being arranged to generate a non-linear trajectory of the mechanical coupling means.

[0061] According to a particular embodiment, the mechanical coupling means comprises three ribbons, namely an actuator ribbon arranged to be connected to the actuator shaft, a first key ribbon, a joining part arranged between the actuator ribbon and the first key ribbon, a second key ribbon arranged to be connected to the key, and a return component arranged between the first key ribbon and the second key ribbon and adapted to receive the terminal ends of the orthogonally extending ribbons.

[0062] For example, the return element may be an "L" shaped lever actuated element or a pulley.

[0063] According to a first alternative embodiment, the return part is a fixed or rotating pulley, such that the ribbon or cable is in contact with the pulley. In operation with a particular configuration of pulleys, the pulley rotates a quarter or the ribbon or cable travels a quarter of the circumference of the fixed pulley. Preferably, the mechanical coupling means further comprises a counter pulley or an axial guide parallel to the axis of the pulley. The counter pulley or guide is placed close to the pulley, such that the ribbon or cable is in simultaneous contact with the pulley on the one hand and the counter pulley or guide on the other hand.

[0064] According to a second alternative embodiment, the mechanical coupling means comprises a lever actuated part. For example, the lever actuated part has the shape of an "L" or a bracket. The lever actuated part comprises an axis of rotation at the intersection of the two arms of the "L" or the two arms of the bracket. According to one embodiment, the "L" actuated part is placed under the key and connected near the key return.

[0065] Optionally, the lever actuated part may form the joining part. One or both ends of the part may be provided with a slot as defined above for the joining part.

[0066] Various embodiments including combinations of the features suggested above are presented below in a non-exhaustive manner. the rotary electric actuator has an axis of rotation parallel to the axis of the key, and the mechanical linkage means comprises a cable or ribbon connecting the actuator to the key; the rotary electric actuator has an axis of rotation parallel to the axis of the key, the mechanical linkage means comprising a cable or ribbon connecting the actuator to the key and a return piece between the actuator and the key for altering the trajectory of the cable or ribbon, the return piece having a pivot axis parallel to the axis of the key; The rotary electric actuator has an axis of rotation parallel to the axis of the key, the mechanical linking means comprises two flexible elements, which may be two cables or two ribbons or a cable and a ribbon, connecting the actuator to the key, and a return part, which has a pivot axis parallel to the axis of the key, the two flexible elements being separated by the return part, the rotary electric actuator has an axis of rotation parallel to the longitudinal direction of the key, the mechanical linkage comprising a cable connecting the actuator to the key; the rotary electric actuator has an axis of rotation parallel to the longitudinal direction of the key, the mechanical coupling means comprises a ribbon connecting the actuator to the key, the coupling means comprising a hole having an oblong cross section to achieve operating clearance in a direction parallel to the longitudinal direction of the key; the rotary electric actuator has an axis of rotation parallel to the longitudinal direction of the key, the mechanical coupling means comprising two ribbons connecting the actuator to the key and an interface piece disposed between the two ribbons; the rotary electric actuator has a rotation axis perpendicular to the longitudinal direction of the key and to the axis of rotation of the key, the mechanical coupling means comprising two flexible elements, which may be one or two cables or two ribbons or one ribbon and one cable, connecting the actuator to the key, and a return part, which has a pivot axis parallel to the axis of the key, the two flexible elements being separated by a return part, which may also be a joining part in the presence of one or two ribbons; the rotary electric actuator has an axis of rotation perpendicular to the longitudinal direction of the key and to the axis of rotation of the key, the mechanical connection means comprising two flexible elements, which may be two ribbons or a ribbon and a cable, connecting the actuator to the key, and an "L"-shaped lever actuating part, with a pivot axis parallel to the axis of the key, the two flexible elements being separated by a lever actuating part, which comprises, at the end intended to connect the actuator ribbons, a hole with an oblong-shaped cross section so as to achieve an operating clearance in a direction parallel to the longitudinal direction of the key, the rotary electric actuator has a rotation axis perpendicular to the longitudinal direction of the key and to the axis of rotation of the key, the mechanical coupling means comprising two ribbons connecting the actuator to the key, a joint part arranged between the two ribbons and, in addition to the joint part, a return part, in particular a pulley, having a pivot axis parallel to the axis of the key, the return part being arranged in contact with the key ribbon to change the trajectory of the key ribbon; The rotary electric actuator has an axis of rotation perpendicular to the longitudinal direction of the key and to the axis of rotation of the key, the mechanical coupling means comprises three ribbons, or two ribbons and a cable, connecting the actuator to the key, the joint part is arranged between the two first ribbons, the return part, in particular the lever actuated part, has in addition to the joint part a pivot axis parallel to the axis of the key, the lever actuated part is arranged between the second ribbon and the third ribbon or cable.

[0067] According to another particular embodiment, the mechanical coupling means comprises at least two ribbons, an actuator ribbon arranged to be connected to the actuator shaft, a key ribbon arranged to be connected to the key, a joint part arranged between the two ribbons and adapted to receive the terminal ends of the ribbons arranged perpendicular to each other, and a pulley with which the key ribbons cooperate.

[0068] According to other alternative embodiments, the rotary electric actuator has an axis of rotation perpendicular to the longitudinal direction of the key and to the axis of rotation of the key and offset with respect to a plane passing through the thickness of the key. In these cases, the return part has a pivot axis parallel to the longitudinal direction of the key. In this configuration, various embodiments are presented below that include combinations of the features proposed above. the mechanical coupling means comprises two flexible elements, which may be two cables or two ribbons or a ribbon and a cable, a return part connecting the actuator to the key and separating the two flexible elements, which in the case of an actuator ribbon and an "L" shaped lever actuating part may be a pulley or an "L" shaped lever actuating part, the latter being provided at the end intended to connect the actuator ribbon with a hole having an oblong-shaped cross section to achieve a working clearance in a direction parallel to the pivot axis of the key, and / or in the case of a key ribbon, the mechanical coupling means comprises a coupling means provided with a hole having an oblong-shaped portion to achieve a working clearance in a direction parallel to the longitudinal direction of the key, the mechanical linking means comprises two ribbons connecting the actuator to the key, a joint part separating the ribbons, and a pulley having a pivot axis parallel to the longitudinal direction of the key and arranged in contact with the key ribbon to change the trajectory of the key ribbon; the mechanical coupling means comprises three flexible elements (which may be three ribbons or two ribbons and one cable) connecting the actuator to the key, a joint part separating the first ribbon and the second ribbon and / or a joint part separating the second ribbon and the third ribbon, a pulley with a pivot axis parallel to the longitudinal direction of the key and arranged to contact the ribbons to change their trajectory, and an "L" shaped lever actuating part separating the two flexible elements, the mechanical coupling means comprising connecting means with holes having an oblong cross section to achieve working clearance in a direction parallel to the longitudinal direction of the key, The mechanical coupling means comprises four ribbons connecting the actuator to the key, a joining part separating the first ribbon from the second ribbon and / or a joining part separating the third ribbon from the fourth ribbon, and an "L" shaped lever actuating part separating the second ribbon from the third ribbon.

[0069] According to one embodiment, the mechanical coupling means comprises at least two ribbons, an actuator ribbon arranged to be connected to the actuator shaft, at least one key ribbon arranged to be connected to the key, and a lever actuating element arranged between the two ribbons and adapted to receive the terminal ends of the orthogonally arranged ribbons.

[0070] For example, each ribbon has the following dimensions: Actuator Ribbon: a length of 25 to 50 millimeters, preferably 15 to 40 millimeters, preferably more than 15 millimeters; The width is between 5 and 10 millimeters, It is 0.05mm thick. Key Ribbon: a length of 15 to 30 millimeters, preferably 5 to 30 millimeters, preferably more than 5 millimeters, preferably more than 10 millimeters; The width is between 5 and 10 millimeters, It is 0.05mm thick.

[0071] Preferably, the mechanical connection means is a metallic connection means. The actuator and key ribbon may be a metallic actuator and key ribbon.

[0072] The material of the ribbon comprises or consists of a metal (steel, preferably stainless steel, or aluminium), or a fibre or composite polymer material, and / or a synthetic fibre fabric, for example Kevlar®.

[0073] The ribbons make it possible to execute the necessary tension acting on the key when the key tape is pulled by the actuator, while allowing a slight bending to ensure compatibility between the rotation of the key and the translational movement of the key tape. A second function provided by the limited flexibility of the ribbons consists of limiting the stroke of the actuators, driven by their own inertia, when the key is decelerated. They make it possible to prevent or extinguish bouncing vibrations. Moreover, flexible ribbon connections do not have the disadvantage of backlash and have the advantage of a stable equilibrium configuration during the release of tension.

[0074] According to another embodiment, the haptic device comprises an actuator stop arranged around or around the rotating shaft of the actuator so as to control the angular movement of the actuator's rotating shaft, especially if the connection means implements a cable. For example, the stop may be arranged on or near the actuator's rotating shaft, for example tangentially. According to one embodiment, the stop is cylindrical. The actuator stop is arranged in the immediate vicinity of the connection means or the actuator. Preferably, the actuator stop is reached at the moment when the key reaches the stop position.

[0075] The presence of at least one element that flexes under pressure and hardens under traction and / or the presence of an actuator stop constitute mechanical means for controlling the displacement of the mechanical coupling means. The control means make it possible to control the angular movement of the rotating shaft of the actuator as a function of the angular movement of the key. They also make it possible to avoid undesired or excessive movements of the coupling means.

[0076] Advantageously, the mechanical means for controlling the displacement of the mechanical connecting means are mechanical in nature and are arranged in the immediate vicinity of the connecting means and the actuator, the means having the function of holding the connecting means and the actuator in a geometric configuration which makes them absolute with respect to the key at the moment when the tension force is stopped.

[0077] Preferably, the mechanical means for controlling the movement of the mechanical linking means is at least one flexible element. The use of a ribbon makes it possible to ensure this geometric restoration function mainly due to its stable natural equilibrium configuration.

[0078] Wire connections, especially those that do not have a natural configuration of stable balance, have the disadvantage of being difficult to install and complicated in limiting the stroke of the motor, which must be guaranteed by other means, i.e. actuator stop means or electrical position control means.

[0079] Complementarily, the actuator can be controlled according to four-quadrant operation and participate in the control of the mechanical linkage means to prevent the motor from rotating under its own momentum.

[0080] Preferably, the tactile device further comprises means for holding the key in an elevated position. Holding it in an elevated position is understood to mean holding it in its original position. The elevated holding means also allows the key to be returned to its original position when the user is not pressing the key. In particular, the elevated holding means may be independent of the rotary electric actuator. For example, the elevated holding means may comprise at least one spring, at least two permanent magnets, or a holding actuator through which an electric current passes continuously when the key thus equipped is not in use.

[0081] According to another embodiment the computation means is capable of controlling the rotary electric actuator to perform a height keeping function via the mechanical linkage means. Preferably the computation means includes a four-quadrant control means for operating the electric actuator.

[0082] The detection means are arranged and configured to detect or measure the position and / or acceleration of the associated key or the force applied to the associated key by a user, which make it possible to inform a calculation algorithm implemented by the calculation means.

[0083] Preferably, the key detection means comprises a sensor for the kinematics of the key, for example a position sensor, a motion sensor, an acceleration sensor, an angular velocity sensor.

[0084] The key detection means includes, for example, a force sensor of the strain gauge type.

[0085] According to one embodiment, the key detection means comprises two sensors.

[0086] According to a variant embodiment, the detection means are arranged under the key, preferably on the underside of the key.

[0087] According to another embodiment, the detection means comprise means for measuring the current in the actuator.

[0088] The computational means preferably includes an integrated microprocessor on an autonomous board, a control interface and software containing a mathematical model of the dynamics of the actual musical instrument mechanism that is to be reproduced.

[0089] Preferably, the computation means comprises an actuator module integrating a mechanical model for controlling at least one key of at least one acoustic musical instrument. The module integrates a mathematical model of the dynamics of the mechanism of the real musical instrument to be reproduced. The module also integrates a mathematical model of the dynamics of the mechanism of the digital keyboard used to reproduce the real musical instrument in the absence of electrical control. Preferably, the computation means comprises an actuator module integrating a mechanical model for controlling at least one key of the keyboard described herein when the associated actuator does not receive electrical current. The module integrates a mathematical model of the dynamics of the mechanism of the keyboard used to reproduce the real musical instrument, made passive by the absence of electrical control. The module also incorporates a mathematical model of the dynamics of the keys, the coupling means and the actuators in the absence of electrical control.

[0090] Regarding the mathematical model of the dynamics of the mechanism of the real instrument that we try to reproduce, see for example the paper "Non-smooth model of the grand piano action" by Anders Thorin (https: / / pastel.archives-ouvertes.fr / pastel-00939493).

[0091] According to a second aspect, the invention proposes a haptic feedback electronic musical instrument keyboard comprising at least one key and at least one haptic device, each key being associated with a device according to one or more of the features of the first aspect.

[0092] According to a third aspect, the invention proposes an electronic musical instrument, for example an electronic piano, comprising at least one haptic device according to one or more of the features of the first aspect or comprising a keyboard according to the second aspect.

[0093] Preferably, the electronic musical instrument comprises several haptic devices, the haptic devices being arranged adjacent to one another. According to one embodiment, the haptic devices are arranged such that their rotary electric actuators are arranged parallel to one another.

[0094] According to a fourth aspect, the invention proposes a method for controlling an electronic musical instrument equipped with at least one haptic device according to one or more of the features of the first aspect.

[0095] The method aims to control at least one rotary electric actuator associated with the key, in response to a given user movement on the key measured by the pressure detection means, to apply a predetermined holding force against the user's loading force, said holding force substantially corresponding to the force acting on the key of a similar conventional or acoustic instrument, in order to obtain the same movement and thus emulate the dynamics of conventional instrument mechanisms.

[0096] This control method includes at least detecting by a detection means that a user has pressed a key; and controlling the actuator in real time to apply tension to the key to resist the pushing force or to apply tension to return the key to its original position.

[0097] The detection means periodically measure the position and / or acceleration of the keys and then transmit this information to the calculation means which calculates the forces generated in the actual instrument mechanism from a mathematical model of the dynamics of the mechanism.

[0098] The computation means must have sufficient computational power to simulate the model of the key in real time. The cycle time (measurement / calculation / actuation) is constrained and defined by the movement of the piano keys. The sampling frequency is for example 2 kHz. At lower values, the simulation of a conventional piano key has instabilities. The computation means is for example a computer.

[0099] Preferably, for transmitting information between the various components, the computing means comprises: Power electronics and Signal electronics; a computing board based on a real-time simulation model; MIDI (Musical Instrument Digital Interface) hub, The device further comprises a router.

[0100] The function of the computation means is to process the measured signals, calculate in real time the dynamics of the traditional and digital keys (simulations) and generate the commands to be applied to the actuators.

[0101] The calculation means calculates the current or voltage to be applied to the actuator based on a dynamic model of the musical instrument to be simulated and real-time measurements from the sensing means.

[0102] Therefore, the control method according to the present invention comprises: Low-cost adjustable and changeable mechanisms; Different mechanisms refer to instruments on the same keyboard but different instruments, for example harpsichord, fortepiano, clavichord or organ, Features that do not exist on acoustic instruments but that may be desirable for modern light touch pianos, for example, allowing for better control by very young piano students. There are no physical problems such as keys without dry friction, the escapement point of the hammer very close to the point of impact on the wire, etc., which are desirable for different reasons, for example greater ease of control when playing with "piano" marks, greater possible repetition rates, but whose possible adoption makes it possible to emulate or simulate the dynamics of the mechanism, which may give rise to some ecological problems.

[0103] The computing board performs calculations in real time to emulate the dynamics of the keys of a conventional keyboard through processing of signals from the sensors, performs measurements of the power electronics circuits associated with the actuators, and optionally performs the application of control algorithms to the force signals with the aim of compensating for certain imperfections of the system, such as delays.

[0104] According to a preferred configuration in which the actuator is associated with a single key, the control method provides closed-loop control of at least one rotary electric actuator, whereby the at least one actuator exerts a variable force over time according to commands given by the computer in real time and relayed by the power electronics.

[0105] Each computing board uses electronic circuits to provide a MIDI code that corresponds to the note played on the key it controls. The code is converted into a signal according to the MIDI standard. The signals of the various computing boards are sent to a MIDI (internal or external) hub, which sends the MIDI code required for the sound synthesis to a computer (in the case of an autonomous prototype) or to a digital piano. In the case of an autonomous prototype, the computer performs the sound synthesis by means of a sound synthesis software, for example the software Pianoteq®.

[0106] Other features and advantages of the present invention will become apparent from the following detailed description of the invention which refers to the accompanying drawings.

[0107] For greater clarity, identical or similar elements of the various embodiments are designated by the same reference numerals in all figures. [Mode for carrying out the invention]

[0108] Figures 1, 2a and 2b show a first embodiment of an electronic musical instrument haptic control device 1. A musical instrument, for example a piano as shown in Figures 3a and 16, is an instrument that consists of a keyboard containing several keys, a single key of which is shown in Figures 1, 2a and 2b.

[0109] The haptic device and the key K are seen in a side view, the key being represented by a horizontal rectangle. The key K represents a piano key. It is pivotally mounted about a pivot axis A1 relative to a frame, for example the frame of a keyboard (see Fig. 3a and Fig. 16). The pivot axis A1 is represented by two mutually perpendicular dashed lines representing a target on a disk representing a rotating shaft. The pivot axis A1 is shown on the left side of Figs. 1, 2a and 2b, below the key K, near a first end, called the proximal end, of the key. Near a second end, called the distal end, opposite the first end, and above the upper surface K1 of the key, the fingers of the user of the instrument are shown and are only visible in Fig. 1.

[0110] Beneath the key, near the distal end, the haptic device comprises means 30 for detecting and / or measuring the presses and movements of the key by the user. With reference to Figure 1, the detection and / or measurement means comprises two movement sensors 31, 32, e.g. accelerometers, arranged to measure the movements of the key and to transmit this information to computational means, also called servo and control means, of the haptic device (not shown).

[0111] The haptic control device 1 comprises a rotary electric actuator 10. Preferably, the actuator is a direct current electric motor whose drive shaft extends along an axis B1. The motor is arranged with respect to the key K such that the axis of rotation B1 is parallel to the longitudinal direction K0 of the key K, in particular such that in the original position the direction K0 and the axis B1 are vertically aligned. In the present embodiment the axis of rotation B1 is substantially horizontal.

[0112] 1, 2, 3a and 16, the haptic control device further comprises a mechanical coupling means 20 connecting the shaft of the motor 10 to the upper surface K1 of the key. The mechanical coupling means 20 comprises several elements or parts connected to each other, namely an assembly means 25 (not visible in Figs. 1 and 2), an actuator ribbon 24 (two actuator ribbons 24a, 24b in Fig. 16), a joining part 23, a key ribbon 22 and a connection means 21.

[0113] The assembly means allows the actuator ribbon to be connected to the rotating shaft of an electric motor (see Figs. 3a and 3b). For example, with reference to Fig. 7, the assembly means 25 comprises a winding part 25e and a clamping part 25s, or a stirrup with two branches. The winding part has a hole arranged to be fitted onto the rotating shaft of the electric motor (see Figs. 3a and 3b). It further has a rectangular part extending radially to the hole, in which a slot is formed to allow the fitting. The clamping part 25s is formed in a U-shape so as to overlap the rectangular part of the winding part 25e. The clamping part includes in one of its branches an internal thread arranged perpendicular to the rectangular part of the winding part. When the actuator ribbon is attached, it is pressed between an inner surface of the clamping part and a first outer surface of the rectangular part (see Figs. 3a and 3b). The surface opposite to the first surface receives the end of a screw attached to the internal thread of the clamping part. The screwing action both closes the slots in the rectangular portion of the winding assembly to tighten the winding assembly onto the drive shaft, and also pushes the end of the actuator ribbon until it is clamped.

[0114] The actuator ribbon 24 is disposed between the assembly means 25 and the interface part 23. The actuator ribbon extends perpendicular and tangential to the rotating shaft of the motor.

[0115] The key ribbon 22 is arranged between the joining part 23 and the connecting means 21. The key ribbon extends vertically along a plane parallel to the transverse plane of the key, particularly in the original position.

[0116] According to another embodiment, with reference to FIG. 16, which is explained by the difference with FIG. 3a, the mechanical coupling means 20 comprises a pair of actuator ribbons 24a and 24b. Each ribbon 24a, 24b connects the actuator 10 to the joint part. The two ribbons are attached around the shaft of the actuator 10 via a sleeve-shaped assembly means 25. The actuator ends of the ribbons 24a, 24b are arranged diametrically opposite. The actuator ribbon 24a is connected directly between the joint part and the actuator. The actuator ribbon 24b is connected between the joint part and the actuator by a wheel 11. The wheel 11 is arranged elevated with respect to the actuator so that the ribbon 24b is wrapped around the wheel 11 and then attached to a point on the circumference of the actuator substantially diametrically opposite to the attachment point of the actuator end of the ribbon 24a. This configuration allows to apply a double traction in opposite directions around the actuator shaft during the actuation of the actuator. The ribbons of the actuators 24a and 24b are arranged substantially symmetrically with respect to a plane parallel to both the axis of the actuator and the longitudinal direction of the key associated with the device comprising the ribbons.

[0117] According to an alternative embodiment represented by figure 17, the actuator comprises two half shafts 111, 112 and the mechanical linking means 20 comprises a single actuator ribbon 24 which passes between the two half shafts of the drive shaft before being connected to the wheel 11. Each half shaft has a rectangular face along its longitudinal axis, one side of which corresponds to the diameter of the shaft and a curved face corresponding to a circular semi-cylinder. The joining of the half shafts makes it possible to obtain a shaft.

[0118] The ribbon (or cable) passes through the shaft of the actuator (motor) between two half rods clamped together on the shaft of the motor, for example by a clamping part consisting of two half cylinders clamped together by two screws.

[0119] The two ends of the ribbon (or cable) meet on the key. In this way, the two ends of the ribbon (or cable) exert the same force on the key (these forces are cumulative), but also exert forces of opposite sign on the shaft of the motor. The result is a force on the key and a pair of forces on the motor that cancel each other out.

[0120] An intermediate redirecting member, such as a pulley or wheel 11, is used to allow the force applied to the key to be pulled straight along the vertical axis without lateral deviation.

[0121] 8a, the joining part 23 comprises two mutually opposing perpendicular slits 26, 27 for receiving the terminal ends of the two ribbons 22, 24. The joining part performs the function of a ribbon orientation converter. A first end of the joining part has a slot 26 arranged to receive the terminal end of the actuator ribbon 24, and a second end opposite the first end has a slot 27 arranged to receive the terminal end of the key ribbon 22.

[0122] According to another embodiment of the joining part, shown in Fig. 8b, the joining part 23 comprises two plates extending in the same vertical direction, the plates being arranged perpendicular to one another and each plate being perforated to receive a means for fastening the ribbons.

[0123] Finally, the connecting means 21 is attached to the upper surface K1 of the key K (Figures 1, 2a and 2b). With reference to Figure 9a, the connecting means has the form of two rods: a connecting rod 21a and a key rod 21b. The connecting rod a comprises, at one end, called the slot end, a slot arranged to receive the key ribbon end. The slot is oriented along a plane parallel to the transverse plane of the key. The key rod comprises a threaded body arranged to fit into an internal thread formed in the key. The key rod comprises a hollow body for receiving the end of the connecting rod opposite the slot end. The peripheral wall of the hollow body comprises a radially extending internal thread for receiving a screw making it possible to lock the position of the connecting rod in the key rod.

[0124] According to another embodiment, shown in figure 9b, the connection means 21 comprises two plates arranged vertically and in different directions relative to each other: the first plate extends horizontally to be attached to the key K, the second plate extends vertically to be connected to the key ribbon. Each plate comprises a hole for passing a screw.

[0125] 1, the connection means are arranged on the key at key points located at a distance equal to 25% of the longitudinal distance of the key from the pivot axis A1. Preferably, the key points are located between the center of the key and the distal end of the key. Preferably, they are mounted as far away as possible from the pivot axis A1.

[0126] For example, the connection means are arranged on the key such that the key point is at a distance of at least 50 mm, preferably at least 100 mm, advantageously at least 150 mm from the pivot axis. The assembly means, in particular the winding parts, are arranged on the motor axis such that the actuator point is located at a distance of 3 mm from the motor axis. In these latter cases (150 and 3 mm), the reduction ratio of the angular displacement between the motor and the key, i.e. the torque multiplication ratio, is equal to 50.

[0127] Preferably, each slot or each hole of the connecting parts is associated with a fastening means, for example a screw, for example an internal thread extending radially or perpendicularly to the axis of the parts to receive the screw.

[0128] With reference to FIG. 2a, the key K is placed in a substantially horizontal or elevated position. When the upper surface K1 and near the distal end of the key are pressed, the key is pivoted so that the distal end is lowered, and the key ribbon 22 is bent at an angle by the pivoting of the key (see FIG. 2b). The actuator ribbon 24 remains vertical and unwound, held by the electric motor 10 supplied with current to reproduce the dynamics of the keyboard mechanism of an acoustic instrument (or any other dynamics previously determined). Each motor is controlled by a current. When pressed, the torque of the motor allows to brake the lowering of the key (generator action). When released, the same current control allows to raise the key (motor action). The torque generated by the motor always keeps the same sign. Only the direction of rotation changes between pressing and releasing the key (2-quadrant action). FIG. 10 shows the power electronics diagram of the device. According to another embodiment, the computation means can use an ad-hoc modification of the power electronics diagram to control the actuators to perform a 4-quadrant action.

[0129] With reference to Figures 3a and 3b, the arrangement of electric motors for a keyboard with a number of keys, in particular black and white piano keys, is shown. The electric motors are arranged so that the rotating shafts are arranged in two horizontal rows, offset so that the mechanical linkages are aligned.

[0130] Figures 4a and 4b show a second embodiment, which is illustrated by its differences with respect to the previous embodiment.

[0131] The illustrated key corresponds to a flat piano key, with a key return R extending from its distal end below the key to form an "L". In this case, the rotary electric actuator and the mechanical coupling means are arranged above the upper surface K2 of the key return. The distance separating the upper surface K2 of the key return from the lower surface K3 is, for example, equal to 45 millimeters. With reference to FIG. 4a, the connection means is attached to the upper surface K2 of the key return. With reference to FIG. 4b, the end of the key ribbon is attached to the distal transverse surface of the key return R.

[0132] According to an alternative embodiment shown in figure 4b, the underside K3 of the key may have a recess, for example of concave shape, to partially receive the actuator. This feature makes it possible to propose an even more compact device.

[0133] According to another alternative embodiment shown in Fig. 4c and explained by the difference with Fig. 4a, the device comprises a threaded rod arranged at the end of the drive shaft of the actuator. Preferably, the threaded rod is a V-thread.

[0134] Furthermore, the device comprises a mounting finger P arranged on the key return, above the threaded rod, preferably substantially parallel to the drive shaft or the threaded rod. According to the embodiment shown, the mounting finger has a cylindrical shape and is attached to a plane perpendicular to the upper surface K1.

[0135] Furthermore, the mechanical connection means 20 comprises two cables, namely cable 24c1 connecting the distal end of the key return to the threaded rod and cable 24c2 connecting the threaded rod to the mounting finger.

[0136] In operation, the key return R and the mounting finger P are united in translation when the key is lowered or raised, for example vertically according to the embodiment shown. The screw V is united with the actuator axis and is rotatable along the geometric axis of the drive shaft. The threaded rod, and in particular the screw V, does not translate.

[0137] Preferably, the mechanical linking means 20 comprises a single cable 24c with two strands 24c1 and 24c2. In the latter case, the cable 24c is wrapped around the screw V one or more times and attached to the screw to prevent the cable from sliding. For example, the cable 24c is attached to the screw or threaded rod by gluing. Preferably, the strands or cable parts 24c1 and 24c2 emerge on the same side of the threaded rod or screw V. The role of the strand of the cable 24c2 (whose end is fixed to the key) is to lock the rotation of the actuator by stopping its momentum when the key reaches the bottom stop. The cable strand 24c2 only exerts a force when the key is stopped and only serves to hold the motor. In operation, when the key is pressed, the cable strand 24c2 wraps around the screw V and the cable strand 24c1 unwinds from the screw V.

[0138] According to yet another alternative embodiment represented by Fig. 4d, it is explained by its difference with respect to the preceding variant. The device further comprises a pulley or wheel 121 and a cable 24d with two strands 24d1 and 24d2. According to Fig. 4d, the pulley 121 is arranged above the screw V and attached to the actuator frame, the axis of the pulley 121 being substantially parallel to the axis of the actuator. The cable 24d moves substantially through the circumference of the pulley 121 and winds partially around the threaded rod or screw V. The strand 24d1 of the cable connecting the distal end of the key returns to the pulley 121 by approaching, without contacting, the threaded rod or screw V and the strand 24d2 of the cable connecting the pulley 121 to the threaded rod or screw V. The connection point of the distal end of the strand 24d2 is fixed on the circumference of the threaded rod at a point diametrically opposite to the connection point of the distal end of the cable strand 24c2. 4d, the connection points are also axially offset. As in the previous variation, strands 24c1 and 24c2 may be attached to the same side of a threaded rod or thread V, or may be axially offset along the circumference of thread V.

[0139] In operation, when the key is pressed, cable strand 24c2 winds around screw V, decreasing the length of the strand, cable strand 24d2 unwinds from screw V, cable strand 24c1 unwinds from screw V, increasing the length of the strand, and cable strand 24d1 increases in length. The two cables 24c and 24d exert a pair of opposing forces on the actuator shaft while exerting a accumulating force on the return of the key. The function of cable 24d is to pull the key like strand 24c1, but thanks to the return pulley 121, it pulls the motor in the opposite direction to that of strand 24c1 while rotating the actuator in the same direction.

[0140] FIG. 5a shows a third embodiment described by its differences with respect to the first embodiment. The electric motor 10 is arranged above the key K and fixed to a frame (not shown). The rotation axis B1 of the electric motor is perpendicular to the longitudinal direction of the key K. The actuator ribbon 24 extends horizontally and tangentially to the rotation shaft of the motor. For simplicity, the assembly means, the joining means and the connection means are not shown here. The mechanical coupling means further comprises a pulley 28 whose rotation axis is parallel to the pivot axis A1. The pulley is connected to a frame (not shown). The pulley allows to receive the key ribbon 22 on its circumference along its path. Between the joining part and the pulley, the parts of the key ribbon extend substantially horizontally. Between the pulley and the connection means, the parts of the key ribbon extend substantially vertically. According to an alternative embodiment shown in FIG. 5b, the device further comprises a cylindrical counter pulley 51, arranged tangentially to the pulley 28. The counter pulley is in contact or quasi-contact with the key ribbon 22. The counter pulley makes it possible to guide and / or control the movement of the key ribbon and thus to keep it around the pulley 28. The counter pulley prevents the key ribbon from coming off the pulley.

[0141] Fig. 5c shows a fourth embodiment, which is described by differences with respect to the previous embodiments. Instead of a pulley 28, the mechanical connection means comprises a bracket 29 whose axis of rotation C1 is parallel to the pivot axis A1. The axis C1 of the bracket is connected to a frame (not shown). The bracket receives the key ribbon 22 along its path. The key ribbon 22 comprises a first key ribbon 22b and a second key ribbon 22a. Between the joint part and the bracket, the first key ribbon 22b extends substantially horizontally. Between the bracket and the connection means, the second key ribbon 22a extends substantially vertically.

[0142] Fig. 6a shows a fifth embodiment, which is illustrated by its differences with respect to the third embodiment. The key shown corresponds to a flat piano key, which is provided with a key return R, as in the second embodiment. An electric motor 10 is arranged below the key K. The rotation axis B1 of the motor is perpendicular to the longitudinal direction of the key and perpendicular to the pivot axis A1. Mechanical coupling means extend below the lower surface K3 of the key. A pulley 28 is arranged between the upper surface of the key return R and the lower surface K3 of the key. Connection means (not shown) are attached to the upper surface K2 of the key return.

[0143] Figure 6b shows a sixth embodiment, which is described by a difference with respect to the preceding embodiments: the pulley 28 is replaced by a bracket 29, the arrangement of which with respect to the key and the actuator ribbon is similar or identical to the fourth embodiment.

[0144] According to an alternative embodiment represented by Fig. 6c, illustrated by a difference with respect to the previous embodiment, the actuator 10 is arranged close to the pivot axis A1. The device further comprises one of ribbon guides 61 making it possible to guide the movement of the actuator ribbon 24. Each ribbon guide comprises a pair of rods spaced apart from one another so that the ribbon can translate between them (see also Fig. 6d).

[0145] Referring to Fig. 6d, which represents an alternative embodiment that can be integrated into all of the previous embodiments, the mechanical coupling means further comprises an actuator stop 42 arranged near the actuator's rotating shaft to limit the angular movement of the shaft. The stop 42 is cylindrical in shape and fixed to the frame. The stop 42 is provided to limit the rotation of the actuator's rotating shaft via the assembly means 25.

[0146] According to an alternative embodiment shown in Fig. 6e, the device comprises a coaxially arranged wheel 291 and roller 292, the diameter of the wheel 291 being larger than that of the roller, for example at least three times larger. The assembly of the wheel 291 and roller 292 is arranged near the key return, such that the key ribbon 22 is connected to the roller 292 and to the distal end of the key return. Compared to the previous embodiment, the actuator ribbon 24 is replaced by a cable 24e having two strands 24e1, called the lower strand, and 24e2, called the upper strand. Preferably, the cable 24e is attached to the wheel 291, in particular making it possible to limit or prevent the sliding of the cable in contact with the circumference of the wheel.

[0147] Furthermore, the actuator 10 is disposed near the pivot axis A1, and the axis of rotation of the actuator is substantially perpendicular to the pivot axis A1. The actuator comprises two rotating shafts, an upper shaft and a lower shaft, each of which is disposed at one axial end of the actuator. The cable 24e has one end connected to the upper shaft, extends to the wheel 291 to form an upper strand 24e2, travels substantially half the circumference of the wheel 291, extends to the lower shaft to form a lower strand 24e<1, and is connected to the lower shaft. One end of 24e1 is wound around the lower part of the axis of the actuator. The ends are wound in different rotational directions, and as one end is wound, the other end is unwound.

[0148] In operation, when the key is pressed, the key return also descends and the pulling on the key ribbon 22 exerts a traction force on the strand of cable 24e1, driving the counterclockwise rotation of the roller and wheel 291 assembly to unwind cable 24e1 from the lower shaft, thus exerting a resistance force and driving the actuator. This alternative embodiment makes it possible to obtain a very large ratio between the rotation angle of the actuator and the rotation angle of the key, which allows a corresponding reduction in the torque required from the actuator relative to the torque applied to the key.

[0149] Fig. 12 shows a seventh embodiment described by its differences with respect to the first embodiment. The electric motor 10 is placed above the upper surface K1 of the key, the rotation axis of the motor extends parallel to the pivot axis A1 of the key. The mechanical coupling means comprises a single ribbon that executes both the actuator ribbon 24 and the key ribbon 22. The assembly means 25 corresponds to the assembly means of Fig. 3a and 3b. The connection means 21 follows the connection means of Fig. 9b. The upper part of Fig. 13 represents two haptic devices according to Fig. 12 connected to a white key. The two actuators associated with the white key are placed on the key, overlapping and offset with respect to each other.

[0150] With reference to the lower part of Fig. 13, an eighth embodiment is shown and is described by its differences with respect to the previous embodiment. Each of the illustrated black keys comprises a key return R that extends under the key to form an "L". In this case, the rotary electric actuator and the mechanical coupling means are arranged above the upper surface K2 of the key return. The keys associated with the black keys are arranged under the key and offset from each other. The connecting means are attached to the front surface of the end of the key return. The terminal end of the key ribbon is attached to the distal transverse surface of the key return R.

[0151] According to an alternative embodiment, seen in the lower part of FIG. 13, the mechanical coupling means comprises a return pulley 28 arranged between the key return R and the electric motor 10 .

[0152] The embodiment of figure 13 proposes a particular arrangement to solve the bulk problem caused by the lateral arrangement of the actuators, whose length is several times the average width of the keys. The figure shows a perspective view of four keys, three of which are associated with actuators and connecting means of configuration AxR1, and the black key in the first plane is associated with actuators and connecting means of configuration AxR1PxR1. The axis of the actuators is parallel to the rotation axis of the keys, and the connecting means are reduced to a single ribbon and its fastening parts.

[0153] Figure 14 shows a ninth embodiment described by its differences with respect to the first embodiment. The mechanical coupling means comprises a single ribbon performing the functions of both the actuator ribbon 24 and the key ribbon 22. The assembly means 25 corresponds to the assembly means of figures 3a and 3b. The ribbon is connected to the key by a particular connection means 21. With reference to figure 15, the connection means is a connection piece 21 comprising a body from which two parallel plates extend perpendicular to the longitudinal direction of the key and perpendicular to the pivot axis of the key, the plates being spaced apart from each other so as to define slots. The slots have a width allowing the insertion of the key end of the ribbon. The plates each have a hole whose axis extends parallel to the pivot axis of the key and the holes are coaxial. In addition, the key end comprises an opening. The connection means comprises a connection shaft arranged to be inserted in the hole and in the opening. According to one particular embodiment, each hole has the shape of an oblong hole so that according to its cross section the connection shaft can translate laterally. Preferably, the longest length of the slot is at least 20% greater than the width (or the shortest length) of the slot. The oblong hole makes it possible to achieve operating clearance in a direction parallel to the longitudinal direction of the key.

[0154] Referring to FIG. 11, a method for calculating the holding force of a conventional or acoustic instrument is shown to simulate its dynamics.

[0155] The different stages of the simulation are described below. Initialization: A preliminary step in which the geometry and coefficients of the system are initialized. Measurement: Measurements of the key's position and acceleration are collected at the current moment, a filter is applied to reduce measurement noise, and the key's velocity is calculated. Geometry update: The positions of the elements of the system are updated with the measurements at the current instant and the results of the solution of the equations at the previous instant. Calculation of force moments, with parallel calculation of contact force moments, weights, spring forces and viscous friction torques. Estimation of Dry Friction Torque at Joints and at Contacts Between Parts: This calculation requires all of the above to complete properly. Calculation of the solutions of each of the simultaneous equations which represent, on the one hand, the dynamics of the mechanical system to be emulated (acoustic musical keyboard or other musical keyboard) and, on the other hand, the dynamics of the haptic interface adopted in the absence of electrical control.

[0156] The present invention has been described above by way of example, and it is understood that those skilled in the art can make different modified embodiments of the present invention without departing from the scope of the present invention. [Brief description of the drawings]

[0157] [Figure 1] FIG. 1 is a schematic side view of a haptic control device according to a first embodiment associated with a key of an electronic upright piano, the device comprising an electric motor and a metal ribbon-type mechanical coupling means between the motor and the top surface of the key, the rotation axis of the motor being parallel to the longitudinal direction of the key. [Figure 2a] 2a is a schematic side view of FIG. 1 showing the movement of the key and the mechanical interlocking means in an exaggerated manner, FIG. 2a showing the original position; FIG. [Figure 2b] 2a shows a schematic side view according to FIG. 1 with an exaggerated view of the movement of the key and the mechanical interlocking means, and FIG. 2b shows the stop position when the user presses the key. [Figure 3a] FIG. 1 is a perspective view of three haptic control devices according to a first embodiment, each device comprising a mechanical linkage according to one embodiment. [Figure 3b]FIG. 3b is a detailed view of FIG. 3a in a zone having a rotating shaft of the actuators, each device comprising an actuator stop arranged near the respective rotating shaft. [Figure 4a] FIG. 11 is a schematic side view of a haptic control device according to a second embodiment, in which the motor is positioned below the underside of the key, the mechanical coupling means is positioned above the upper surface of the key return of a flat piano, and the rotation axis of the actuator is parallel to the longitudinal direction of the key. [Figure 4b] 4b is a cross-sectional view of an exemplary embodiment of a haptic device according to FIG. 4a. [Figure 4c] 4b is a perspective view of an exemplary embodiment of a haptic device that is a variation of the embodiment shown in FIG. 4a. [Figure 4d] FIG. 2 is a top perspective view of the system of the previous figure. [Figure 5a] FIG. 11 is a schematic perspective view of a haptic control device according to a third embodiment, in which the motor and mechanical coupling means are positioned above the top surface of the key, the rotation axis of the actuator is perpendicular to the longitudinal and pivot axes of the key, and the mechanical coupling means further comprises a pulley cooperating with the key ribbon. [Figure 5b] FIG. 5b is a view according to FIG. 5a, further comprising a counter pulley whose peripheral surface is in contact with the key ribbon, the counter pulley being arranged substantially tangentially relative to the pulley. [Figure 5c] FIG. 11 is a schematic perspective view of a haptic control device according to a fourth embodiment, in which the motor and mechanical coupling means are arranged above the top surface of the key, the rotation axis of the actuator is perpendicular to the longitudinal direction and pivot axis of the key, and the mechanical coupling means further comprises a rotating bracket and an additional ribbon arranged between the actuator ribbon and the bracket. [Figure 6a] FIG. 11 is a schematic side view of a haptic control device according to a fifth embodiment, in which the motor is positioned under the underside of the key and the mechanical coupling means is connected to the upper surface of the key return of a flat piano, the actuator's rotation axis is perpendicular to the longitudinal and pivot axes of the key, and the mechanical coupling means further comprises a pulley, and the key ribbon guide may be positioned in close proximity to the pulley but is not shown. [Figure 6b]FIG. 13 is a schematic side view of a haptic control device according to a sixth embodiment, in which the motor is positioned under the underside of the key and the mechanical coupling means is connected to the upper surface of the key return of a flat piano, the actuator rotation axis is perpendicular to the longitudinal direction and to the pivot axis of the key, the mechanical coupling means further comprises a rotating bracket and an additional ribbon positioned between the bracket and the actuator ribbon, the actuator ribbon being guided by a series of double guides with a vertical axis. [Figure 6c] FIG. 6b is a cross-sectional view of an exemplary embodiment of a haptic device according to FIG. 6b, further comprising an actuator ribbon guide. [Figure 6d] FIG. 13 is a partial perspective view of a haptic control device according to an alternative embodiment having an actuator stop located near the actuator rotation shaft, showing the actuator ribbon assembly means in contact with the stop. [Figure 6e] FIG. 6B is a side view of an exemplary embodiment of a haptic device that is a variation of the embodiment shown in FIGS. 6a, 6b, and 6c, comprising a winch wheel. [Figure 7] FIG. 2 is a perspective view of an assembly means according to one embodiment. [Figure 8a] FIG. 2 is a perspective view of an exemplary embodiment of an interface piece between two ribbons. [Figure 8b] FIG. 13 is a perspective view of another exemplary embodiment of an interface piece between two ribbons. [Figure 9a] FIG. 2 is a perspective view of an exemplary embodiment of a connecting piece; [Figure 9b] FIG. 13 is a perspective view of another exemplary embodiment of a connecting piece; [Figure 10] 1 shows an electrical diagram of a haptic control device. [Figure 11] FIG. 1 shows a diagram for calculating the holding force as a function of the dynamics of a conventional or acoustic instrument. [Figure 12] FIG. 13 is a schematic perspective view of a haptic control device according to a seventh embodiment associated with a key of an electronic upright piano, the device comprising an electric motor and a mechanical coupling means comprising a single metal ribbon between the motor and the top surface of the key, the rotation axis of the motor being parallel to the pivot axis of the key. [Figure 13] FIG. 13 is a schematic perspective view of four tactile control devices, two according to the previous embodiment and two according to the eighth embodiment, each device comprising a motor arranged under the underside of an associated key and a mechanical coupling means connecting the key return of the associated key, the mechanical coupling means comprising a single metal ribbon between the motor and the key return surface of the key, the rotation axis of the motor being parallel to the pivot axis of the key, and one of the two devices further comprising a return pulley. [Figure 14] FIG. 13 is a schematic perspective view of a haptic control device according to a ninth embodiment associated with the key of an electronic upright piano, the device comprising an electric motor and a mechanical coupling means comprising a single metal ribbon between the motor and the top surface of the key, the rotation axis of the motor being parallel to the longitudinal direction of the key, the mechanical coupling means comprising connection means arranged to achieve operating clearance in the longitudinal direction. [Figure 15] 15 is a perspective view of the connecting means according to FIG. 14 with a hole along an axis perpendicular to the longitudinal direction of the key. [Figure 16] FIG. 13 is a perspective view of three haptic control devices according to a tenth embodiment, each device comprising a mechanical linkage means according to a particular embodiment comprising two flexible actuator elements per device. [Figure 17] FIG. 15 is a perspective view of a haptic control device according to an eleventh embodiment, which is a variation of the previous embodiment.

Claims

1. A haptic control device (1) for the keys of a keyboard on an electronic musical instrument intended to reproduce the feel of using a similar acoustic musical instrument, comprising: said device is arranged to be associated with a key (K) of said electronic musical instrument pivotally mounted relative to a frame about a pivot axis (A1), said key extending in a longitudinal direction and having an angular movement between a high angular position called the home position and a low angular position called the stop; The device, detection means (30) for detecting said dynamic state information of said key; - calculation means for calculating the instantaneous resistance force applied to said key in response to said key being depressed as a function of the dynamic information thus detected; a rotary electric actuator (10) arranged to generate said resistive force; and a mechanical coupling means (20) arranged between said rotary electric actuator and said key for applying said resistance force to said key, said mechanical coupling means (20) comprising at least one element that flexes under pressure and stiffens under traction.

2. 2. The device according to claim 1, wherein the rotary electric actuator has an axis of rotation parallel to the pivot axis (A1) of the key.

3. The device of claim 1 , wherein the rotary electric actuator has an axis of rotation parallel to a longitudinal axis of the key.

4. The device of claim 1 , wherein the rotary electric actuator has an axis of rotation perpendicular to the longitudinal axis of the key and the axis of rotation of the key.

5. 2. The device according to claim 1, wherein the key end is attached to the upper (K1) or lower (K3) surface of the key.

6. 2. The device according to claim 1, wherein said mechanical connection means (20) comprises a key end attached to an upper surface (K2) of the key return of said key.

7. said mechanical coupling means (20) comprising an actuator end and a key end, said key end being attached to said key; on the other hand, a lever arm distance separating said pivot axis (A1) from the key point at which said key end of said mechanical coupling means is attached to said key; a lever arm distance separating the axis of rotation of the rotary electric actuator from an actuator point where the actuator terminus of the mechanical linkage is attached to the actuator shaft; The device of claim 1 , wherein the ratio of

8. 2. The device of claim 1, wherein the mechanical connection means (20) comprises at least two ribbons that bend under pressure and stiffen under traction.

9. 2. The device of claim 1, wherein the mechanical connection means (20) comprises at least two cables that bend under pressure and stiffen under traction.

10. 2. The device of claim 1, wherein the mechanical connection means (20) comprises at least one ribbon that bends under pressure and hardens under traction, and at least one cable that bends under pressure and hardens under traction.

11. 2. The device of claim 1, wherein the mechanical connection means (20) comprises at least three ribbons that bend under pressure and stiffen under traction.

12. 2. The device of claim 1, wherein the at least one element that bends under pressure and hardens under traction is a cable that bends under pressure and hardens under traction or a ribbon that bends under pressure and hardens under traction.

13. 2. The device of claim 1, wherein the mechanical connecting means (20) comprises at least two flexible elements comprising at least two ribbons that bend under pressure and harden under traction, and a joining part (23) arranged between the two ribbons, the joining part having two opposing ribbon receiving surfaces perpendicular to each other for receiving the terminal ends of the two ribbons.

14. 2. The device of claim 1, wherein the mechanical connection means (20) comprises three flexible elements, two flexible actuator elements (24a, 24b) arranged to be connected to the actuator shaft (10), a flexible key element (22) arranged to be connected to the key, and an interface part arranged between the key element and the two flexible actuator elements, the interface part being arranged to receive the terminal ends of the three ribbons.

15. 2. The device of claim 1, wherein the mechanical coupling means (20) comprises at least two flexible elements, a flexible actuator element (24) arranged to be connected to the actuator shaft (10), a flexible key element (22) arranged to be connected to the key, and a return part having a pivot axis, the return part being arranged between two flexible elements, the return part being arranged to generate a non-linear trajectory of the mechanical coupling means.

16. 2. The device according to claim 1, wherein the mechanical coupling means (20) comprises three ribbons, namely an actuator ribbon (24) arranged to be connected to the actuator shaft (10), a first key ribbon (22b), a joint part (23) arranged between the actuator ribbon and the first key ribbon (22b), a second key ribbon (22a) arranged to be connected to the key, and a return component arranged between the first key ribbon (22b) and the second key ribbon (22a) and adapted to receive the orthogonally extending end portions of the ribbons.

17. 16. The device of claim 15, wherein the return element is an "L" shaped lever actuating element or a pulley.

18. 2. The device of claim 1, comprising an actuator stop (42) disposed on or around the rotatable shaft of the actuator to control the angular movement of the rotatable shaft of the actuator.

19. The device of claim 1 , wherein the computing means comprises an actuator module integrating a mechanical model for controlling at least one key of at least one acoustic musical instrument.

20. The device of claim 1 , wherein said computing means comprises four-quadrant control means for operating said electric actuator.

21. 13. An electronic musical instrument keyboard with haptic feedback comprising at least one key and at least one haptic control device according to claim 1, each key being associated with a haptic control device.

22. An electronic musical instrument, for example an electronic piano, comprising at least one haptic device (1) according to claim 1.

23. A method for controlling an electronic musical instrument comprising at least one haptic control device (1) according to claim 1, comprising: detecting, by said detection means, that said user has pressed said key; and controlling the actuator in real time to apply a tension to the key to resist the pushing force or to return the key to its original position.

24. 24. A method according to any one of the preceding claims, wherein the detection means periodically measure the position and / or acceleration of the keys and then transmit this information to the calculation means which calculates the forces generated in the actual musical instrument mechanism from a mathematical model of the dynamics of the mechanism.

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