阅读说明：本技术 使用动力转向系统的辅助电机以根据振动确定周期生成测试周期 (Using an auxiliary motor of a power steering system to generate a test period from a vibration determination period ) 是由 马蒂厄·卢梭 克里斯多夫·拉维耶 于 2018-12-03 设计创作，主要内容包括：本发明涉及一种用于表征动力转向系统(1)的方法,该方法用于根据经验确定所述系统(1)的至少一种特性,所述动力转向系统包含至少一个转向盘(2)、配备有齿条(4)的转向机构(3)、以及至少一个辅助电机(7),除了转向阶段之外,所述方法包含：自动激活辅助电机(7)的步骤(a),在此期间,计算机(13)被用于自动生成激活指令并将其应用于辅助电机(7),而无需在转向盘(2)上进行任何外部的操作,激活指令遵循被称为预先设定的探索周期(CY)的一个或多个周期,以在至少一个探索周期或在所述至少一个探索周期(CY)结束时,测量至少一个指标参数(P7_mes,T7_mes,P4_mes,T2_mes,V2_mes),该指标参数特定于由动力转向系统对辅助电机的自动激活的响应并是对期望特性的表征,在转向阶段期间将动力转向系统(1)分配给车辆的驾驶,以使所述车辆遵循根据所述车辆相对于其环境的状况而确定的轨迹。(The invention relates to a method for characterizing a power steering system (1) comprising at least one steering wheel (2), a steering mechanism (3) equipped with a rack (4), and at least one auxiliary motor (7), for empirically determining at least one characteristic of the system (1), said method comprising, in addition to a steering phase: a step (a) of automatically activating the auxiliary motor (7), during which a computer (13) is used to automatically generate and apply an activation command to the auxiliary motor (7), without any external operation on the steering wheel (2), the activation command following one or more cycles called predetermined search Cycles (CY), to measure at least one index parameter (P7_ mes, T7_ mes, P4_ mes, T2_ mes, V2_ mes) at the end of at least one exploration cycle or at the end of said at least one exploration Cycle (CY), the index parameter is specific to the response of the power steering system to the automatic activation of the auxiliary motor and is indicative of a desired characteristic, a power steering system (1) is assigned to the driving of a vehicle during a steering phase so that the vehicle follows a trajectory determined according to the condition of the vehicle with respect to its environment.)

1. A method for characterizing a power steering system (1) intended to empirically determine at least one characteristic of said power steering system (1), called "desired characteristic", said power steering system comprising at least one heading defining device (2), such as a steering wheel (2), which allows to define a direction called "steering angle" (a1) of said power steering system; a steering mechanism (3) equipped with at least one movable member (4), such as a rack (4), the position (P4) of which is adapted so as to correspond to a selected steering angle (a 1); and at least one auxiliary motor (7) arranged to be able to drive the steering mechanism (3), the method comprising, in addition to a driving phase:

a step (a) of automatically activating said auxiliary motor (7), during which a computer (13) is used to automatically generate and apply to said auxiliary motor (7) an activation setting that follows one or more preset periods called "exploration periods" (CY), without any external action on said heading definition device (2);

a measurement step (b) according to which at least one physical parameter, called "target parameter" (P7_ mes, T7_ mes, P4_ mes, T2_ mes, V2_ mes), specific to the response provided by the power steering system to the automatic activation of the auxiliary electric machine (7) and representative of the desired characteristic, is measured during the exploration cycle or upon completion of the exploration Cycle (CY);

then an analysis step (c) during which the desired characteristic is quantified from the measurement of the indicator parameter;

-applying, during the automatic activation step (a), a force exploration cycle (CY _ force) in the form of a vibration exploration cycle (CY _ sine) according to which the auxiliary motor (7) is excited by means of an alternating periodic torque setpoint (T7), preferably sinusoidal, with the frequency (f7) of said periodic torque setpoint varying over a predetermined range over a plurality of frequency steps, preferably comprised between 0Hz and 200Hz, to characterize the frequency response of the power steering system (1) to vibrations, and more particularly to identify, whenever present, one or more resonance frequencies and/or one or more cut-off frequencies and, if necessary, a respective bandwidth, characterized in that the amplitude, i.e. the peak, of said torque setpoint (T7) corresponds to a value comprised between 20% and 50% of the maximum auxiliary torque that the auxiliary motor is able to output,

wherein, during the driving phase, the power steering system (1) is dedicated to the driving of a vehicle so as to cause the vehicle to follow a path determined according to the condition of the vehicle with respect to its environment.

2. The method according to claim 1, characterized in that the method allows determining at least one desired characteristic in a mechanical resonance frequency of the steering mechanism (3) in response to vibrations, a cut-off frequency or a bandwidth of the steering mechanism (3).

3. A power steering system (1) intended to equip a vehicle and comprising:

at least one heading defining device (2), such as a steering wheel, which enables a driver to define a steering angle (A1) of the power steering system;

a steering mechanism (3) equipped with at least one movable member (4), such as a rack, the position (P4) of which is adapted to correspond to a selected steering angle; and

at least one auxiliary motor (7) arranged to be able to drive the steering mechanism (3),

the power steering system (1) comprises, on the one hand: a first on-board module (8), called "assistance module", which contains a first set of functions called "assistance law", which, when the power steering system is dedicated to the driving of a vehicle, allows the generation of driving settings to the auxiliary motor to cause the vehicle to follow a path determined according to the conditions of the vehicle with respect to its environment; and another aspect includes: -a second on-board module (13), called "characterization module", which contains a second set of functions called "characterization functions" distinct from said assistance law and which allows to automatically implement a characterization method during driving periods in which the power steering system is not dedicated to the vehicle, said characterization method being intended to empirically determine at least one characteristic of the power steering system, called "desired characteristic", said characterization method comprising: a step (a) of automatically activating the auxiliary motor (7), during which the second onboard module (13) automatically generates and applies to the auxiliary motor (7) activation setpoints (T7, V7, P7), without any external action on the course defining device (2), the activation settings (T7, V7, P7) follow one or more predetermined periods, called "exploration periods" (CY), to allow the measurement step (b) to be carried out, during or at the completion of the exploration cycle, measuring according to the measuring step (b) at least one physical parameter, called "indicator parameter" (P7_ mes, T7_ mes, P4_ mes, T2_ mes, V2_ mes), specific to a response provided by the power steering system (1) to the automatic activation of the auxiliary motor (7) and characteristic of the desired characteristic; then an analysis step (c) during which the desired characteristic is quantified from the measurement of the index parameter, during the automatic activation step (a), a force exploration cycle (CY _ force) is applied in the form of a vibration exploration cycle (CY _ sine), according to which the auxiliary motor (7) is excited by means of an alternating periodic torque setpoint (T7), preferably sinusoidal, with the frequency (f7) of the periodic torque setpoint varying over a predetermined range over a plurality of frequency steps, preferably comprised between 0Hz and 200Hz, to characterize the frequency response of the power steering system (1) to vibrations, and more particularly to identify, whenever present, one or more resonance frequencies and/or one or more cut-off frequencies and, if necessary, the corresponding bandwidth, characterized in that the amplitude, i.e. the peak, of the torque setpoint (T7) corresponds to the maximum bandwidth that can be output by the auxiliary motor, included in the torque setpoint (T7) A value between 20% and 50% of the assistance torque.

4. A power steering system according to claim 3, characterized in that the second on-board module (13) comprises a vibration characterization function using a vibration exploration cycle (CY _ sine), according to which the auxiliary electric machine (7) is excited by means of an alternating periodic torque setpoint (T7), preferably sinusoidal, with a frequency (f7) that varies over a predetermined range over a plurality of frequency steps, and the torque (T2) and/or displacement (P2) produced at the steering wheel in response to the excitation is measured at different frequency steps.