Patents by Inventor Christophe Ravier
Christophe Ravier has filed for patents to protect the following inventions. This listing includes patent applications that are pending as well as patents that have already been granted by the United States Patent and Trademark Office (USPTO).
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Patent number: 11597433Abstract: A method for determining a setpoint torque for a steering wheel of a power-assisted steering system of a vehicle, the setpoint torque making it possible to determine a motor torque applied directly or indirectly by a control motor to the steering wheel, and the setpoint torque being at least determined by a reversibility function designed to bring a steering wheel angle of the steering wheel toward the steering wheel angle at which the vehicle will follow a trajectory in a straight line, the reversibility function comprising a first step in which a target speed of the steering wheel is determined depending on the steering wheel angle, wherein the target speed is also a function of a yaw rate of the vehicle.Type: GrantFiled: October 1, 2019Date of Patent: March 7, 2023Assignee: JTEKT EUROPEInventors: Pierre Larminy, André Michelis, Pascal Moulaire, Christophe Ravier
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Publication number: 20220041208Abstract: A method for determining a setpoint torque for a steering wheel of a power-assisted steering system of a vehicle, the setpoint torque making it possible to determine a motor torque applied directly or indirectly by a control motor to the steering wheel, and the setpoint torque being at least determined by a reversibility function designed to bring a steering wheel angle of the steering wheel toward the steering wheel angle at which the vehicle will follow a trajectory in a straight line, the reversibility function comprising a first step in which a target speed of the steering wheel is determined depending on the steering wheel angle, wherein the target speed is also a function of a yaw rate of the vehicle.Type: ApplicationFiled: October 1, 2019Publication date: February 10, 2022Applicant: JTEKT EUROPEInventors: Pierre LARMINY, André MICHELIS, Pascal MOULAIRE, Christophe RAVIER
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Publication number: 20220041211Abstract: A method for determining a setpoint torque for a steering wheel of an electric power steering system of a vehicle, the setpoint torque helping determine an engine torque applied directly or indirectly to the steering wheel, the setpoint torque being a function of at least one equivalent lateral acceleration having a dimension of an acceleration, wherein the equivalent lateral acceleration is weighted by a gain dependent on at least a steering wheel torque.Type: ApplicationFiled: August 21, 2019Publication date: February 10, 2022Applicant: JTEKT EUROPEInventors: André MICHELIS, Pascal MOULAIRE, Christophe RAVIER, Pierre LARMINY
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Publication number: 20210164869Abstract: A method for a power steering system for empirically determining at least one property of the system, power steering system including at least one steering wheel, a steering mechanism provided with a rack, and at least one assist motor, method having, outside a steering phase during which the power steering system is assigned to the driving of a vehicle in order to cause vehicle to follow a trajectory which is determined as a function of the situation of vehicle with respect to its environment, a step (a) of automatically activating the assist motor, during which step a computer is used to automatically generate and apply to the assist motor; at least one indicator parameter which is specific to the response by the powersteering system to the automatic activation of the assist motor and which is characteristic of the desired property.Type: ApplicationFiled: December 3, 2018Publication date: June 3, 2021Applicant: JTEKT EUROPEInventors: Matthieu LOUSSAUT, Christophe RAVIER
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Publication number: 20200391793Abstract: A power steering system having at least one steering wheel, steering mechanism provided with rack, and at least one servo motor, the method having, outside steering phase during which power steering system is assigned to driving of vehicle to cause vehicle to follow trajectory which is determined as function of the situation of vehicle with respect to its environment, step (a) of automatically activating the servo motor, during which step computer is used to automatically generate and apply the servo motor, without requiring any external action on steering wheel, activation instruction that follows one or more cycles referred to as pre-established exploration cycles in order to measure, during at least one exploration cycle or at the end of at least one exploration cycle, at least one indicator parameter which is specific to response by power steering system to automatic activation of servo motor and which is characteristic of desired property.Type: ApplicationFiled: December 3, 2018Publication date: December 17, 2020Applicant: JTEKT EUROPEInventors: Matthieu LOUSSAUT, Christophe RAVIER
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Publication number: 20200391792Abstract: A method for characterizing a power steering system for empirically determining at least one property of the system, the power steering system including at least one steering wheel, a steering mechanism provided with a rack, and at least one assist motor, the method including, outside a steering phase during which the power steering system is assigned to the driving of a vehicle in order to cause the vehicle to follow a trajectory which is determined as a function of the situation of the vehicle with respect to its environment, a step (a) of automatically activating the assist motor, during which step a computer is used to automatically generate and apply to the assist motor, without requiring any external action on the steering wheel, an activation instruction that follows one or more cycles referred to as pre-established exploration cycles for measuring.Type: ApplicationFiled: December 3, 2018Publication date: December 17, 2020Applicant: JTEKT EUROPEInventors: Matthieu LOUSSAUT, Christophe RAVIER
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Publication number: 20200277005Abstract: A method for a power steering system for empirically determining at least one property of the system including at least one steering wheel, a steering mechanism with a rack, and at least one assist motor, the method including, outside a steering phase during which the power steering system is assigned to drive a vehicle to follow a trajectory determined as a situation function of the vehicle with respect to its environment, a step (a) of automatically activating the assist motor, during which a computer automatically generates and applies to the assistance motor, without requiring action on the steering wheel, an activation instruction following one or more pre-established exploration cycles for measuring, during or at the end of the at least one exploration cycle, at least one indicator parameter is specific to the power steering system response to the automatic activation of the assist motor and is a desired property characteristic.Type: ApplicationFiled: December 3, 2018Publication date: September 3, 2020Applicant: JTEKT EUROPEInventors: Matthieu LOUSSAUT, Christophe RAVIER
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Patent number: 10549775Abstract: A method for estimating the ageing of a steering mechanism during which the ageing of the steering mechanism is assessed by calculating a value called «ageing value» according to an ageing function (old, old2, ene) which corresponds to the integral, over time, of an expression which is weighted by a stress indicator (Tm(u), Ts(u)) the value of which at each considered instant (u) is representative of the intensity of a stress force (Tm, Ts), such as the operating force exerted by the assist motor, which is undergone by the steering mechanism at the considered instant.Type: GrantFiled: April 7, 2015Date of Patent: February 4, 2020Assignee: JTEKT EUROPEInventors: Sébastien Bourdrez, Pascal Moulaire, Romaric Pregniard, Christophe Ravier
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Patent number: 10293852Abstract: A method for detecting a situation of loss of grip of a vehicle provided with a steering system operated by a steering wheel, the method including a step (a) of evaluating a first indicator of loss of grip (P1) by calculating, as the first indicator of loss of grip (P1), the partial derivative ( P ? ? 1 = ? ? . ? ? ) , relative to a variable (?) representative of the angular position of the steering wheel, of a driving parameter which is representative of the yaw rate ({dot over (?)}) of the vehicle.Type: GrantFiled: November 16, 2015Date of Patent: May 21, 2019Assignee: JTEKT EUROPEInventors: André Michelis, Christophe Ravier, Pascal Moulaire
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Patent number: 10286947Abstract: The invention concerns a method for detecting a transition (4?) in a noisy signal, which involves submitting a noisy signal (?Signal) carrying an item of information used for managing the power steering, said method comprising a derivation sub-step (a1), which involves evaluating the time derivative of the noisy signal (?Signal/?t), following by a selective filtering sub-step (a2) which involves comparing said time derivative of the noisy signal (?Signal/?t) with a predefined variation threshold (Spic) in order to detect the appearance of a derivative peak (7), greater than said variation threshold (Spic), evaluating the holding time (dpic) of said derivative peak, during which the time derivative of the noisy signal (?Signal/?t) is held above said variation threshold (Spic), and checking if said peak holding time (Spic) reaches or exceeds a predefined minimum time threshold (d0).Type: GrantFiled: February 27, 2015Date of Patent: May 14, 2019Assignee: JTEKT EUROPEInventors: Sébastien Bourdrez, Pascal Moulaire, Christophe Ravier
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Patent number: 10227088Abstract: A method for managing a power steering system, including a step (a) of detecting a reversal in the steering direction which involves acquiring a signal, referred to as a “motor torque signal” (CMot), representative of the assistance force (Cassist) delivered by the power steering motor, then evaluating the time derivative (?CMot/?t) of the motor torque signal, then comparing the time derivative of the motor torque signal to a predefined variation threshold (Spic) in order to detect a derivative peak, greater than the variation threshold (Spic), that indicates a reversal in the steering direction. The method next includes a friction evaluation step (b) which involves evaluating the friction from the drop, during the reversal in the steering direction, in a so-called “actuation force signal” (Caction), which is representative of the total actuation force exerted together on the power steering by the driver and by the power steering motor.Type: GrantFiled: February 27, 2015Date of Patent: March 12, 2019Assignee: JTEKT EUROPEInventors: Sébastien Bourdrez, Pascal Moulaire, Christophe Ravier
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Patent number: 10183695Abstract: The present invention concerns a method for determining the position of a movable steering member (1, 2, 3) belonging to a steering mechanism (4) of a vehicle that comprises at least a first movable member (1), such as a shaft (1) of an assistance motor (M), and a second movable member (2), such as a rack (2), which cooperate with each other by means of at least one first link (L1), said method comprising a step (a) that involves measuring the position (?1) of the first member (1), then a step (b) that involves calculating the instantaneous position (?2) of the second member (2) from said position of the first member (?1), and a correction step (d) during which the calculation of the position (?2) of the second member (2) is adapted, taking into consideration the offset (???) in the position of the second member (2) that results from the elastic deformation of the first link (L1) under the force (C1) transmitted by the latter.Type: GrantFiled: September 1, 2014Date of Patent: January 22, 2019Assignee: JTEKT EUROPEInventors: Romaric Pregniard, Loïc Bastien, Christophe Ravier, Sébastien Bourdrez
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Patent number: 10180378Abstract: A method for evaluating the frictions in a power steering mechanism, the method including a step of acquiring a series of characterization points, during which are measured, for several different values taken successively by the assistance force during the operation of the steering mechanism, the corresponding friction values, so as to empirically obtain a series of distinct characterization points each associating a measured friction value to a measured value representative of the assistance force, then a step of constructing an empirical friction model, during which a correlation law is established between the characterization points constitutive of the series of characterization points, from the scatter chart formed by the series of the characterization points.Type: GrantFiled: March 9, 2015Date of Patent: January 15, 2019Assignee: JTEKT EUROPEInventors: Sébastien Bourdrez, Pascal Moulaire, Christophe Ravier
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Patent number: 10139297Abstract: A method determines a link force within a power-steering mechanism of a vehicle, the method including a step (a) of determining an actuation force, which involves determining the actuation force that results from the assistance force exerted by the assistance motor and the driver force exerted by the driver of the vehicle on the steering mechanism; a step (b) of assessing dry friction; and a step (c) of calculating the link force, which has a summation sub-step which involves calculating an expression representing the link force, which uses the algebraic sum of the actuation force and the dry friction force, and a filtering sub-step which involves applying a low-pass filter in order to smooth the result of the expression when the expression is calculated upon a steering reversal of the steering mechanism.Type: GrantFiled: June 19, 2015Date of Patent: November 27, 2018Assignee: JTEKT EUROPEInventors: Sébastien Bourdrez, Pascal Moulaire, Christophe Ravier
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Patent number: 9937951Abstract: A reference position in a power steering system is defined by acquiring a first edge position corresponding to a first edge of a first index pulse generated when a movable steering member passes an indexed position in a first movement direction; acquiring a second edge position corresponding to a second edge of a second index pulse generated when the movable steering member passes the same indexed position in a second movement position opposite the first movement direction; and calculating the reference position from the first edge position and the second edge position.Type: GrantFiled: January 29, 2015Date of Patent: April 10, 2018Assignee: JTEKT EUROPEInventors: Romaric Pregniard, Christophe Ravier, Xavier Palandre
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Publication number: 20170320517Abstract: A method for detecting a situation of loss of grip of a vehicle provided with a steering system operated by a steering wheel, said method being in that it comprises a step (a) of evaluating a first indicator of loss of grip (P1) comprising calculating, as the first indicator of loss of grip (P1), the partial derivative ( P ? ? 1 = ? ? . ? ? ) , relative to a variable (?) representative of the angular position of the steering wheel, of a driving parameter which is representative of the yaw rate ({dot over (?)}) of the vehicle.Type: ApplicationFiled: November 16, 2015Publication date: November 9, 2017Applicant: JTEKT EUROPEInventors: André MICHELIS, Christophe RAVIER, Pascal MOULAIRE
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Publication number: 20170144698Abstract: A method for estimating the ageing of a steering mechanism during which the ageing of the steering mechanism is assessed by calculating a value called <<ageing value>> according to an ageing function (old, old2, ene) which corresponds to the integral, over time, of an expression which is weighted by a stress indicator (Tm(u), Ts(u)) the value of which at each considered instant (u) is representative of the intensity of a stress force (Tm, Ts), such as the operating force exerted by the assist motor, which is undergone by the steering mechanism at the considered instant.Type: ApplicationFiled: April 7, 2015Publication date: May 25, 2017Applicant: JTEKT EUROPEInventors: Sébastien BOURDREZ, Pascal MOULAIRE, Romaric PREGNIARD, Christophe RAVIER
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Publication number: 20170131164Abstract: A method determines a link force within a power-steering mechanism of a vehicle, the method including a step (a) of determining an actuation force, which involves determining the actuation force that results from the assistance force exerted by the assistance motor and the driver force exerted by the driver of the vehicle on the steering mechanism; a step (b) of assessing dry friction; and a step (c) of calculating the link force, which has a summation sub-step which involves calculating an expression representing the link force, which uses the algebraic sum of the actuation force and the dry friction force, and a filtering sub-step which involves applying a low-pass filter in order to smooth the result of the expression when the expression is calculated upon a steering reversal of the steering mechanism.Type: ApplicationFiled: June 19, 2015Publication date: May 11, 2017Applicant: JTEKT EUROPEInventors: Sébastien BOURDREZ, Pascal MOULAIRE, Christophe RAVIER
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Publication number: 20170023445Abstract: A method for evaluating the frictions in a power steering mechanism, the method including a step of acquiring a series of characterization points, during which are measured, for several different values taken successively by the assistance force during the operation of the steering mechanism, the corresponding friction values, so as to empirically obtain a series of distinct characterization points each associating a measured friction value to a measured value representative of the assistance force, then a step of constructing an empirical friction model, during which a correlation law is established between the characterization points constitutive of the series of characterization points, from the scatter chart formed by the series of the characterization points.Type: ApplicationFiled: March 9, 2015Publication date: January 26, 2017Applicant: JTEKT EUROPEInventors: Sébastien BOURDREZ, Pascal MOULAIRE, Christophe RAVIER
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Publication number: 20170015350Abstract: A method for managing a power steering system, including a step (a) of detecting a reversal in the steering direction which involves acquiring a signal, referred to as a “motor torque signal” (CMot), representative of the assistance force (Cassist) delivered by the power steering motor, then evaluating the time derivative (?CMot/?t) of the motor torque signal, then comparing the time derivative of the motor torque signal to a predefined variation threshold (Spic) in order to detect a derivative peak, greater than the variation threshold (Spic), that indicates a reversal in the steering direction. The method next includes a friction evaluation step (b) which involves evaluating the friction from the drop, during the reversal in the steering direction, in a so-called “actuation force signal” (Caction), which is representative of the total actuation force exerted together on the power steering by the driver and by the power steering motor.Type: ApplicationFiled: February 27, 2015Publication date: January 19, 2017Applicant: JTEKT EUROPEInventors: Sébastien BOURDREZ, Pascal MOULAIRE, Christophe RAVIER