CN113167597A - Detection system for vehicle steering capable of measuring torque and multi-turn absolute steering wheel angle - Google Patents

Detection system for vehicle steering capable of measuring torque and multi-turn absolute steering wheel angle Download PDF

Info

Publication number
CN113167597A
CN113167597A CN201980075777.5A CN201980075777A CN113167597A CN 113167597 A CN113167597 A CN 113167597A CN 201980075777 A CN201980075777 A CN 201980075777A CN 113167597 A CN113167597 A CN 113167597A
Authority
CN
China
Prior art keywords
signal
angular position
position sensor
calculation
alpha
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Pending
Application number
CN201980075777.5A
Other languages
Chinese (zh)
Inventor
M·勒尼
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
EFI Automotive SA
Original Assignee
Electricfil Automotive SAS
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Electricfil Automotive SAS filed Critical Electricfil Automotive SAS
Publication of CN113167597A publication Critical patent/CN113167597A/en
Pending legal-status Critical Current

Links

Images

Classifications

    • G—PHYSICS
    • G01—MEASURING; TESTING
    • G01D—MEASURING NOT SPECIALLY ADAPTED FOR A SPECIFIC VARIABLE; ARRANGEMENTS FOR MEASURING TWO OR MORE VARIABLES NOT COVERED IN A SINGLE OTHER SUBCLASS; TARIFF METERING APPARATUS; MEASURING OR TESTING NOT OTHERWISE PROVIDED FOR
    • G01D5/00—Mechanical means for transferring the output of a sensing member; Means for converting the output of a sensing member to another variable where the form or nature of the sensing member does not constrain the means for converting; Transducers not specially adapted for a specific variable
    • G01D5/12—Mechanical means for transferring the output of a sensing member; Means for converting the output of a sensing member to another variable where the form or nature of the sensing member does not constrain the means for converting; Transducers not specially adapted for a specific variable using electric or magnetic means
    • G01D5/14—Mechanical means for transferring the output of a sensing member; Means for converting the output of a sensing member to another variable where the form or nature of the sensing member does not constrain the means for converting; Transducers not specially adapted for a specific variable using electric or magnetic means influencing the magnitude of a current or voltage
    • G01D5/142—Mechanical means for transferring the output of a sensing member; Means for converting the output of a sensing member to another variable where the form or nature of the sensing member does not constrain the means for converting; Transducers not specially adapted for a specific variable using electric or magnetic means influencing the magnitude of a current or voltage using Hall-effect devices
    • G01D5/145—Mechanical means for transferring the output of a sensing member; Means for converting the output of a sensing member to another variable where the form or nature of the sensing member does not constrain the means for converting; Transducers not specially adapted for a specific variable using electric or magnetic means influencing the magnitude of a current or voltage using Hall-effect devices influenced by the relative movement between the Hall device and magnetic fields
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B62—LAND VEHICLES FOR TRAVELLING OTHERWISE THAN ON RAILS
    • B62D—MOTOR VEHICLES; TRAILERS
    • B62D15/00—Steering not otherwise provided for
    • B62D15/02—Steering position indicators ; Steering position determination; Steering aids
    • B62D15/021—Determination of steering angle
    • B62D15/0215—Determination of steering angle by measuring on the steering column
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B62—LAND VEHICLES FOR TRAVELLING OTHERWISE THAN ON RAILS
    • B62D—MOTOR VEHICLES; TRAILERS
    • B62D15/00—Steering not otherwise provided for
    • B62D15/02—Steering position indicators ; Steering position determination; Steering aids
    • B62D15/021—Determination of steering angle
    • B62D15/0235—Determination of steering angle by measuring or deriving directly at the electric power steering motor
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B62—LAND VEHICLES FOR TRAVELLING OTHERWISE THAN ON RAILS
    • B62D—MOTOR VEHICLES; TRAILERS
    • B62D6/00—Arrangements for automatically controlling steering depending on driving conditions sensed and responded to, e.g. control circuits
    • B62D6/08—Arrangements for automatically controlling steering depending on driving conditions sensed and responded to, e.g. control circuits responsive only to driver input torque
    • B62D6/10—Arrangements for automatically controlling steering depending on driving conditions sensed and responded to, e.g. control circuits responsive only to driver input torque characterised by means for sensing or determining torque
    • G—PHYSICS
    • G01—MEASURING; TESTING
    • G01D—MEASURING NOT SPECIALLY ADAPTED FOR A SPECIFIC VARIABLE; ARRANGEMENTS FOR MEASURING TWO OR MORE VARIABLES NOT COVERED IN A SINGLE OTHER SUBCLASS; TARIFF METERING APPARATUS; MEASURING OR TESTING NOT OTHERWISE PROVIDED FOR
    • G01D5/00—Mechanical means for transferring the output of a sensing member; Means for converting the output of a sensing member to another variable where the form or nature of the sensing member does not constrain the means for converting; Transducers not specially adapted for a specific variable
    • G01D5/12—Mechanical means for transferring the output of a sensing member; Means for converting the output of a sensing member to another variable where the form or nature of the sensing member does not constrain the means for converting; Transducers not specially adapted for a specific variable using electric or magnetic means
    • G01D5/14—Mechanical means for transferring the output of a sensing member; Means for converting the output of a sensing member to another variable where the form or nature of the sensing member does not constrain the means for converting; Transducers not specially adapted for a specific variable using electric or magnetic means influencing the magnitude of a current or voltage
    • G01D5/20—Mechanical means for transferring the output of a sensing member; Means for converting the output of a sensing member to another variable where the form or nature of the sensing member does not constrain the means for converting; Transducers not specially adapted for a specific variable using electric or magnetic means influencing the magnitude of a current or voltage by varying inductance, e.g. by a movable armature
    • G01D5/204—Mechanical means for transferring the output of a sensing member; Means for converting the output of a sensing member to another variable where the form or nature of the sensing member does not constrain the means for converting; Transducers not specially adapted for a specific variable using electric or magnetic means influencing the magnitude of a current or voltage by varying inductance, e.g. by a movable armature by influencing the mutual induction between two or more coils
    • G01D5/2053—Mechanical means for transferring the output of a sensing member; Means for converting the output of a sensing member to another variable where the form or nature of the sensing member does not constrain the means for converting; Transducers not specially adapted for a specific variable using electric or magnetic means influencing the magnitude of a current or voltage by varying inductance, e.g. by a movable armature by influencing the mutual induction between two or more coils by a movable non-ferromagnetic conductive element
    • G—PHYSICS
    • G01—MEASURING; TESTING
    • G01D—MEASURING NOT SPECIALLY ADAPTED FOR A SPECIFIC VARIABLE; ARRANGEMENTS FOR MEASURING TWO OR MORE VARIABLES NOT COVERED IN A SINGLE OTHER SUBCLASS; TARIFF METERING APPARATUS; MEASURING OR TESTING NOT OTHERWISE PROVIDED FOR
    • G01D5/00—Mechanical means for transferring the output of a sensing member; Means for converting the output of a sensing member to another variable where the form or nature of the sensing member does not constrain the means for converting; Transducers not specially adapted for a specific variable
    • G01D5/12—Mechanical means for transferring the output of a sensing member; Means for converting the output of a sensing member to another variable where the form or nature of the sensing member does not constrain the means for converting; Transducers not specially adapted for a specific variable using electric or magnetic means
    • G01D5/244—Mechanical means for transferring the output of a sensing member; Means for converting the output of a sensing member to another variable where the form or nature of the sensing member does not constrain the means for converting; Transducers not specially adapted for a specific variable using electric or magnetic means influencing characteristics of pulses or pulse trains; generating pulses or pulse trains
    • G01D5/24471—Error correction
    • G01D5/24476—Signal processing
    • G—PHYSICS
    • G01—MEASURING; TESTING
    • G01D—MEASURING NOT SPECIALLY ADAPTED FOR A SPECIFIC VARIABLE; ARRANGEMENTS FOR MEASURING TWO OR MORE VARIABLES NOT COVERED IN A SINGLE OTHER SUBCLASS; TARIFF METERING APPARATUS; MEASURING OR TESTING NOT OTHERWISE PROVIDED FOR
    • G01D5/00—Mechanical means for transferring the output of a sensing member; Means for converting the output of a sensing member to another variable where the form or nature of the sensing member does not constrain the means for converting; Transducers not specially adapted for a specific variable
    • G01D5/12—Mechanical means for transferring the output of a sensing member; Means for converting the output of a sensing member to another variable where the form or nature of the sensing member does not constrain the means for converting; Transducers not specially adapted for a specific variable using electric or magnetic means
    • G01D5/244—Mechanical means for transferring the output of a sensing member; Means for converting the output of a sensing member to another variable where the form or nature of the sensing member does not constrain the means for converting; Transducers not specially adapted for a specific variable using electric or magnetic means influencing characteristics of pulses or pulse trains; generating pulses or pulse trains
    • G01D5/245—Mechanical means for transferring the output of a sensing member; Means for converting the output of a sensing member to another variable where the form or nature of the sensing member does not constrain the means for converting; Transducers not specially adapted for a specific variable using electric or magnetic means influencing characteristics of pulses or pulse trains; generating pulses or pulse trains using a variable number of pulses in a train
    • G01D5/2451—Incremental encoders
    • G01D5/2452—Incremental encoders incorporating two or more tracks having an (n, n+1, ...) relationship
    • G—PHYSICS
    • G01—MEASURING; TESTING
    • G01L—MEASURING FORCE, STRESS, TORQUE, WORK, MECHANICAL POWER, MECHANICAL EFFICIENCY, OR FLUID PRESSURE
    • G01L3/00—Measuring torque, work, mechanical power, or mechanical efficiency, in general
    • G01L3/02—Rotary-transmission dynamometers
    • G01L3/04—Rotary-transmission dynamometers wherein the torque-transmitting element comprises a torsionally-flexible shaft
    • G01L3/10—Rotary-transmission dynamometers wherein the torque-transmitting element comprises a torsionally-flexible shaft involving electric or magnetic means for indicating
    • G01L3/101—Rotary-transmission dynamometers wherein the torque-transmitting element comprises a torsionally-flexible shaft involving electric or magnetic means for indicating involving magnetic or electromagnetic means
    • G01L3/104—Rotary-transmission dynamometers wherein the torque-transmitting element comprises a torsionally-flexible shaft involving electric or magnetic means for indicating involving magnetic or electromagnetic means involving permanent magnets
    • G—PHYSICS
    • G01—MEASURING; TESTING
    • G01L—MEASURING FORCE, STRESS, TORQUE, WORK, MECHANICAL POWER, MECHANICAL EFFICIENCY, OR FLUID PRESSURE
    • G01L3/00—Measuring torque, work, mechanical power, or mechanical efficiency, in general
    • G01L3/02—Rotary-transmission dynamometers
    • G01L3/04—Rotary-transmission dynamometers wherein the torque-transmitting element comprises a torsionally-flexible shaft
    • G01L3/10—Rotary-transmission dynamometers wherein the torque-transmitting element comprises a torsionally-flexible shaft involving electric or magnetic means for indicating
    • G01L3/101—Rotary-transmission dynamometers wherein the torque-transmitting element comprises a torsionally-flexible shaft involving electric or magnetic means for indicating involving magnetic or electromagnetic means
    • G01L3/105—Rotary-transmission dynamometers wherein the torque-transmitting element comprises a torsionally-flexible shaft involving electric or magnetic means for indicating involving magnetic or electromagnetic means involving inductive means
    • G—PHYSICS
    • G01—MEASURING; TESTING
    • G01D—MEASURING NOT SPECIALLY ADAPTED FOR A SPECIFIC VARIABLE; ARRANGEMENTS FOR MEASURING TWO OR MORE VARIABLES NOT COVERED IN A SINGLE OTHER SUBCLASS; TARIFF METERING APPARATUS; MEASURING OR TESTING NOT OTHERWISE PROVIDED FOR
    • G01D2205/00—Indexing scheme relating to details of means for transferring or converting the output of a sensing member
    • G01D2205/20—Detecting rotary movement
    • G01D2205/26—Details of encoders or position sensors specially adapted to detect rotation beyond a full turn of 360°, e.g. multi-rotation

Landscapes

  • Physics & Mathematics (AREA)
  • Engineering & Computer Science (AREA)
  • General Physics & Mathematics (AREA)
  • Chemical & Material Sciences (AREA)
  • Combustion & Propulsion (AREA)
  • Transportation (AREA)
  • Mechanical Engineering (AREA)
  • Electromagnetism (AREA)
  • Signal Processing (AREA)
  • Measurement Of Length, Angles, Or The Like Using Electric Or Magnetic Means (AREA)
  • Steering Control In Accordance With Driving Conditions (AREA)
  • Power Steering Mechanism (AREA)

Abstract

The invention relates to a detection system for a steering mechanism, comprising: -a first angular position sensor (11) measuring the angle of the electric motor (3) and transmitting a first signal; -a second angular position sensor (12) which measures the angle of the steering mechanism between the reduction gear (4) and the first side of the torsion bar (7) and transmits a second signal; -a third angular position sensor (13) measuring the angle of the steering mechanism on the second side of the torsion bar (7) and transmitting a third signal; and a processing unit (15) which proceeds on the basis of the first signal and the second signalRow vernier calculation to produce absolute steering wheel angle (theta) over more than one mechanical turn2) Proportional first calculation signal
Figure DDA0003069323950000011
And on the other hand to calculate a signal from the first signal, the second signal and the first signal
Figure DDA0003069323950000012
Is angle-weighted summed with the third signal to produce a second calculated signal proportional to the torque (T)
Figure DDA0003069323950000013

Description

Detection system for vehicle steering capable of measuring torque and multi-turn absolute steering wheel angle
Technical Field
The present invention relates in general to the field of detection systems for measuring the torque and multi-turn absolute steering wheel angle of a steering mechanism of a vehicle.
A preferred application of the invention relates to a sensing system for measuring torque and multi-turn absolute steering wheel angle of a power steering mechanism of a vehicle.
Another application of the invention relates to a detection system for measuring the torque and the multi-turn absolute steering wheel angle of a steering mechanism of a vehicle, wherein the steering wheel is mechanically decoupled from the wheels.
Background
Conventionally, power steering includes an electric motor equipped with a reduction gear that applies torque to assist a steering mechanism (i.e., a steering column or a steering rack) of a vehicle. Operation of the power steering mechanism requires knowledge of the strength of the torque applied to the steering mechanism and the steering wheel angle or angle lock.
Generally, a steering wheel of a vehicle is designed to rotate about one and a half turns to the left and right from a neutral point. In other words, the steering wheel may rotate about three revolutions from the left end to the right end. Therefore, the power steering must be equipped with an angle lock sensor capable of detecting an angular range of three turns or more (360 degrees x 3) in order to appropriately detect the angle lock. In addition, the steering wheel angle is also required for the operation of other functions of the vehicle (e.g., electronic stability control, or a new driving assistance function).
Patent FR2964190 by the MMT company proposes a device for magnetic detection of the absolute steering wheel angle of a plurality of turns, in particular implementing a magnet and a magnetosensitive probe. The detection device also requires a system (gear) for converting the movement, which causes the detection device to become expensive.
Patent application EP3090921 to NSK corporation describes a device for detecting the angular locking of a vehicle, which comprises a cursor calculation section that performs a cursor calculation based on the angle of the steering shaft and the angle of the shaft of the auxiliary electric motor. The apparatus also enables a determination of a portion of a neutral period including a neutral point based on the reference angle calculated by the vernier calculation, and a portion of specifying a neutral point that specifies the neutral point based on the neutral period and a stored neutral point value. The device only allows for multiple turns of angular lock to be determined after the training step, so that the device does not learn angular lock from activation.
Patent FR2872896 by MMT describes a torque sensor using angular deformation of a torsion bar of known stiffness. This differential angular deformation (differential angular deformation) includes several magnetic concentrators, a magnetic target, and a hall effect sensing probe. The sensor is complex in design and only measures the angle between the input shaft and the output shaft. It does not provide information about the angle of the input and output shafts relative to the vehicle chassis.
Patent application DE 1020090397664 of the BMW company describes a detection system for measuring the torque and the multi-turn absolute steering wheel angle of a steering mechanism of a vehicle, wherein the steering wheel is mechanically decoupled from the wheels. This type of steering mechanism, known as "steer-by-wire", comprises an electrical or hydraulic connection between the steering wheel and the wheels. An electric motor equipped with a reduction gear provides drag torque to the steering mechanism. This document proposes to measure the steering wheel angle not only on the basis of an angular position sensor that measures the angle of the electric motor but also on the basis of a further hall-effect probe that detects the leakage flux of the magnetized target member of the torque sensor (MMT type) and is located on the side of the reduction gear of the torsion bar. The use of conventional torque sensors results in expensive detection systems and has not proven the robustness of position sensors that measure leakage flux.
The object of the present invention is to remedy the drawbacks of the prior art and at the same time propose a new detection system for a steering mechanism of a vehicle, allowing to measure the torque and the absolute steering wheel angle over more than one mechanical turn, without adding additional gears and without implementing a training phase, comprising a position sensor that is simpler and less burdened than the prior art.
Disclosure of Invention
In order to achieve this object, the subject of the invention relates to a new detection system for a steering mechanism of a vehicle, which allows to measure the torque and the absolute steering wheel angle over more than one mechanical turn, the steering mechanism comprising a torsion bar and being equipped with an electric motor provided with a reduction gear.
According to the invention, the detection system comprises:
-a first angular position sensor having N1 pairs of poles, where N1 is an integer greater than or equal to 1, which measures the angle of the electric motor and transmits a first signal;
-a second angular position sensor having N2 pairs of poles, where N2 is an integer greater than or equal to 1, which measures the angle of the steering mechanism between the reduction gear and the first side of the torsion bar, which second angular position sensor delivers a second signal;
-a third angular position sensor having N3 pairs of poles, where N3 is an integer greater than or equal to 1, the third angular position sensor measuring the angle of the steering mechanism on a second side of the torsion bar opposite the first side and transmitting a third signal;
and a processing unit which, on the one hand, performs a cursor calculation based on at least the first signal and the second signal to produce a first calculation signal proportional to the absolute steering wheel angle over more than one mechanical revolution, and, on the other hand, performs an angle-weighted summation of one of the signals derived from the first signal, the second signal and the first calculation signal with a third signal to produce a second calculation signal proportional to the torque.
The device according to the invention also comprises in combination one and/or the other of the following additional features:
the processing unit considers the first calculation signal to correspond to the absolute steering wheel angle over more than one mechanical turn and the second calculation signal to correspond to the applied torque;
-the processing unit performs a cursor calculation to generate a first calculation signal:
Figure BDA0003069323930000031
wherein, Θ is fs(p1α1+p2α2)
And, fsIs a mathematical sawtooth function with a slope equal to 1, where q1And q is2Is selected as a fixed weighting coefficient, and alpha1Is a signal generated by a first angular position sensor, alpha2Is a signal generated by a second angular position sensor;
and wherein p is1、p2And NturnsFor the numerical coefficients, these are chosen and must satisfy the following conditions:
Figure BDA0003069323930000032
wherein, Delta theta2Is the peak-to-peak variation in absolute steering wheel angle over more than one mechanical revolution, and RredIs the reduction ratio of the reduction gear;
advantageously, the weighting factor q1And q is2Can be chosen to be equal to:
if it is notN2＜N1RredThen, then
Figure BDA0003069323930000041
If N is present2＞N1RredThen, then
Figure BDA0003069323930000042
Wherein σ1Is a typical magnitude of error for the first angular position sensor, and σ2Is a typical magnitude of error for the second angular position sensor.
According to another variant embodiment, the processing unit performs a vernier calculation to generate the first calculation signal
Figure BDA0003069323930000043
The first calculation signal is:
Figure BDA0003069323930000044
wherein the content of the first and second substances,
Figure BDA0003069323930000045
Figure BDA0003069323930000046
Figure BDA0003069323930000047
Figure BDA0003069323930000048
and, fsIs a mathematical sawtooth function with a slope equal to 1, where pgcd is the "maximum common denominator" operator, where,
Figure BDA0003069323930000049
and
Figure BDA00030693239300000410
is selected as a fixed weighting coefficient, and1is a signal generated by a first angular position sensor, alpha2Is the signal generated by the second angular position sensor, alpha3Is a signal generated by a third angular position sensor;
and wherein c2、c3、
Figure BDA00030693239300000411
And
Figure BDA00030693239300000412
for the numerical coefficients, these are chosen and must satisfy the following conditions:
Figure BDA0003069323930000051
and wherein, Δ θ2Is the peak-to-peak variation in absolute steering wheel angle over more than one mechanical revolution, and RredIs the reduction ratio of the reduction gear;
according to a first variant embodiment, the second calculation signal is:
Figure BDA0003069323930000052
wherein f issIs a mathematical sawtooth function with a slope equal to 1, alpha2Is the signal generated by the second angular position sensor, alpha3Is the signal generated by the third angular position sensor, and G is the stiffness of the torsion bar, and wherein k2、k3For numerical coefficients, these numerical coefficients are selected and must beThe following conditions must be satisfied:
Figure BDA0003069323930000053
wherein, Delta thetashiftIs the peak-to-peak variation in angular deformation of the torsion bar;
according to a second variant embodiment, the second calculation signal is:
Figure BDA0003069323930000054
wherein f issIs a mathematical sawtooth function with a slope equal to 1, alpha1Is a signal generated by a first angular position sensor, alpha3Is the signal generated by the third angular position sensor, and G is the stiffness of the torsion bar, and wherein k1、k3For the numerical coefficients, these are chosen and must satisfy the following conditions:
Figure BDA0003069323930000061
wherein, Delta thetashiftIs the peak-to-peak variation in angular deformation of the torsion bar;
according to a third variant embodiment, the second calculation signal is:
Figure BDA0003069323930000062
wherein f issIs a mathematical sawtooth function with a slope equal to 1,
Figure BDA0003069323930000063
is the first calculation signal, alpha3Is the signal generated by the third angular position sensor, and G is the stiffness of the torsion bar, and wherein k3For a numerical coefficient, the numerical coefficient is chosen and must satisfy the following condition:
Figure BDA0003069323930000064
wherein, Delta thetashiftIs the peak-to-peak variation in angular deformation of the torsion bar;
-the processing unit verifies whether the set of measurement signals and calculation signals belongs to the set of acceptable values, the processing unit transmitting an alarm signal when the set of values does not belong to the set of acceptable values;
the first, second and/or third angular position sensors are hall effect position sensors, magnetoresistive sensors, fluxgate sensors, inductive sensors, eddy current sensors or variable magnetoresistive sensors or a combination of sensors;
the second angular position sensor and the third angular position sensor are eddy current position sensors comprising a common detection probe comprising a common support plate for the windings of the second angular position sensor and the third angular position sensor.
Another subject of the invention relates to a steering mechanism equipped with a detection system according to the invention, which executes a steering command as a function of the absolute steering wheel angle and the applied torque over more than one mechanical turn.
Drawings
Various other features will be apparent from the description given below with reference to the accompanying drawings, which show by way of non-limiting example the forms of embodiment of the subject matter of the invention.
Fig. 1 is a diagram showing a detection system according to the invention which allows to measure the torque of the steering mechanism of a vehicle and the absolute steering wheel angle over more than one mechanical turn.
Fig. 2 to 4 are block diagrams showing three modified embodiments for calculating the applied torque.
Fig. 5 shows the shape of the signal delivered by the three angular position sensors implemented by the detection system according to the invention, which is a function of the steering wheel angle (in degrees) and for the maximum torque applied.
FIG. 6 shows a first calculated signal proportional to the absolute steering wheel angle over more than one mechanical revolution for different torque values
Figure BDA0003069323930000071
FIG. 7 shows a second calculated signal proportional to torque for different values of steering wheel angle
Figure BDA0003069323930000072
Fig. 8 and 9 are diagrams showing two variant embodiments of the second and third sensors in the form of eddy current position sensors.
Detailed Description
As more precisely seen in fig. 1, the subject of the invention relates in a general sense to a detection system 1 which allows to measure the torque T of a steering mechanism 2 of a vehicle and the absolute steering wheel angle θ over more than one mechanical turn2. According to a preferred exemplary application, which will be described in the remainder of the description, the detection system 1 makes it possible to measure the torque and the multi-turn absolute steering wheel angle of a power steering mechanism of a vehicle. Of course, the detection system 1 is also suitable for measuring the torque and the multi-turn absolute steering wheel angle of the steering mechanism of a vehicle, wherein the steering wheel is mechanically decoupled from the wheels.
The steering mechanism 2 comprises an electric motor 3 provided with a reduction gear 4, the reduction gear 4 being of a reduction ratio RredThe electric motor 3 applies a torque to a steering mechanism (in the example shown, a steering column 5) of the vehicle provided with steering wheels 6. Conventionally, the steering wheel 6 may be rotated about three turns from the left end to the right end. The electric motor 3 applies an assist torque to a steering mechanism of the vehicle in the case of power steering, and applies a drag torque to the steering mechanism of the vehicle in the case where the steering wheel is mechanically separated from the wheels in steering.
Of course, the reduction gear 4 may apply an assist torque to a steering rack, which is not shown and is used to turn the wheels.
The steering mechanism 2 further comprises a torsion bar 7, which in the illustrated example is mounted on a steering column 5, which steering column 5 is located between the reduction gear 4 and the steering wheel 6. The torsion bar 7 is made in any suitable manner to allow the torque applied to the steering mechanism to be measured by angular deformation. The torque T applied to the torsion bar 7 is the first quantity to be measured.
According to the invention, the detection system 1 comprises a first angular position sensor 11 having N1 pairs of poles, where N1 is an integer greater than or equal to 1. The first angular position sensor 11 measures the angle θ of the rotor of the electric motor 31And transmits the first signal alpha1. It should be noted that this first angular position sensor 11 can be used in an auxiliary steering mechanism in general, since it allows to control the electric motor 3 of the auxiliary steering mechanism.
The detection system 1 comprises a second angular position sensor 12 having N2 pairs of poles, where N2 is an integer greater than or equal to 1. The second angular position sensor 12 measures the angle θ of the steering mechanism between the reduction gear 4 and a first side of the torsion bar 7 (i.e., the side opposite to the steering wheel 6)2. The angle theta of the steering mechanism2Between the reduction gear 4 and the torsion bar 7, i.e. upstream of the torsion bar. The second angular position sensor 12 delivers a second signal alpha2. It should be noted that the second angular position sensor 12 measures the angle θ of the steering mechanism relative to the vehicle chassis2。
The fact of choosing an integer N2 pairs of poles greater than or equal to 1 allows the second sensor to have a simple and inexpensive design. As a result of this, the second signal α2It is not absolute over more than one mechanical revolution.
As will be explained in the rest of the description, the detection system 1 is intended to determine a reference steering wheel angle which conventionally corresponds to an absolute steering wheel angle θ over more than one mechanical turn2. The multi-turn absolute steering wheel angle theta2Is the second quantity to be measured.
The detection system 1 comprises a third angular position sensor 13 having N3 pairs of poles, wherein,n3 is an integer greater than or equal to 1. The third angular position sensor 13 measures the angle θ of the steering mechanism on a second side of the torsion bar 7 (i.e., opposite to the first side of the torsion bar 7)3. This third angular position sensor 13 is mounted on a portion of the steering column directly associated with the steering wheel 6, measuring the angle of the steering wheel downstream of the torsion bar 7 in a non-absolute manner. The third angular position sensor 13 delivers a third signal alpha3. It should be noted that the third angular position sensor 13 measures the angle θ of the steering with respect to the vehicle chassis3。
According to the invention, a mathematical function f is definedsIt is a mathematical sawtooth function with a slope equal to 1 and when the input data is zero, the value of this function is zero. The mathematical function fsSo that the angle defined in degrees can be converted to an angle between-180 ° and 180 ° are excluded:
fs：x→((x+180)mod 360)-180
where mod is the modulus operator that gives the remainder of the division. Function fsIs a sawtooth function with a slope equal to 1, between-180 ° and 180 ° (180 ° and 180 ° are not included), and zero crossing when x equals zero. Conventionally, this document uses angles defined in degrees, but it is likely that the same function will be defined by other units of angle. For example, a function f that converts an arbitrary angle defined in radians to an angle between-pi and pi (-pi and pi are not included)sIs defined by the formula:
fs：x→((x+π)mod 2π)-π
alternatively, when the function fsFunction f, when defined by an angle in radianssCan also be defined in a fully equivalent manner by:
fs：x→atan2(sin(x)，cos(x))
where sin and cos are conventional trigonometric functions and where atan2 is a function giving the angular coordinates of a certain point in the euclidean plane (defined between-pi and pi (-pi and pi are not included)).
Of course, other units, such as a number of bits, may be used.
The angular deformation of the torsion bar 7 is denoted θshift. Angular deformation thetashiftAnd torque T is:
Figure BDA0003069323930000091
where G is the stiffness of the torsion bar 7.
By convention, the angle θ is considered to be2Indicating a reference steering wheel angle. From the foregoing, the independent mechanical angle θ2，θshiftAnd dependent mechanical angle theta1，θ3The mathematical relationship between can be modeled as follows:
θ1＝Rred.θ2
θ3＝θ2+θshift
reference steering wheel angle theta to be measured2Having a value expressed as Δ θ2Peak-to-peak variation of. The torque to be measured has a peak-to-peak variation expressed as Δ T. This means that the angular deformation of the torsion bar 7 to be measured has a peak-to-peak variation, expressed as Δ θ equal to Δ T/Gshift。
First signals α generated by the first angular position sensor 11, the second angular position sensor 12 and the third angular position sensor 13, respectively1A second signal alpha2And a third signal alpha3Equal to:
α1＝fs(N1.θ1)
α2＝fs(N2.θ2)
α3＝fs(N3.θ3)
from the foregoing, it can be derived that the signal α1、α2And alpha3Each of which is comprised in the interval [ -180 °; 180 degree]In relation to the mechanical angle theta1，θ2，θ3This is not generally the case.
It is also important to note that the present invention is not limited to cornersThe position sensors 11, 12, 13 unambiguously generate the signal α1、α2、α3To the processing unit 15. In general, in the context of a physical embodiment, the angular position sensors 11, 12, 13 transmit the information item α in encoded form1、α2、α3To facilitate transmission and to optimize the robustness of these signals with respect to noise and any sources of interference. For example, the signal α may be represented by two signals SsinAnd ScosOf the form of the two signals SsinAnd ScosDefined by the following equation:
Figure BDA0003069323930000101
Figure BDA0003069323930000102
where A is the amplitude of the signal. Of course, the processing unit 15 then has to match the signal SsinAnd ScosDecoding is performed to retrieve the signal alpha. In the previous example, decoding is done as follows:
Figure BDA0003069323930000103
where atan2 is a function giving the angular coordinates of a point in the euclidean plane (defined between-pi and pi (-pi and pi are not included)).
According to the invention, the detection system 1 further comprises a processing unit 15, the processing unit 15 receiving the first signal α1A second signal alpha2And a third signal alpha3And is configured to perform calculations to produce an absolute steering wheel angle theta over more than one mechanical revolution2Proportional first calculation signal
Figure BDA0003069323930000104
And a second calculation signal proportional to the applied torque T
Figure BDA0003069323930000105
The processing unit 15 is implemented by any programmed computer system and is configured to perform the processing and computing operations according to the invention.
The processing unit 15 is based on at least the first signal a1And a second signal alpha2Performing a vernier calculation to generate a first calculation signal proportional to the absolute steering wheel angle over more than one mechanical revolution
Figure BDA0003069323930000106
And on the other hand from the first signal alpha1A second signal alpha2And a first calculation signal
Figure BDA0003069323930000107
One of the signals obtained in (a) and the third signal alpha3Performing an angle weighted summation to generate a second calculated signal proportional to the torque T
Figure BDA0003069323930000108
According to a first variant embodiment, the processing unit 15 performs a vernier calculation to generate a first calculation signal
Figure BDA0003069323930000109
The first calculation signal
Figure BDA00030693239300001010
Is composed of
Figure BDA00030693239300001011
Wherein the content of the first and second substances,
-Θ＝fs(p1α1+p2α2)
-fsis a mathematical function as defined previously and is,
-q1and q is2Is a designer choice to minimize sensor errorFixed weighting coefficients for the differences. Simplest selection (q)1＝0，q20) defines a signal that is not always optimal in terms of noise suppression and measurement error suppression
Figure BDA0003069323930000111
As a function of (c). There are many other possible alternatives, e.g. (q)1＝0，q2＝1/(N2Nturns) Is a (q) or (q)1＝1/(N1RredNturns)，q20). In general, the coefficient q1And q is2Depends on the accuracy of the two angular position sensors 11, 12 for the vernier effect.
-α1Is a signal generated by a first angular position sensor 11, alpha2Is the signal generated by the second angular position sensor 12;
parameter p1、p2And NturnsFor the numerical coefficients, these are chosen by the designer and must satisfy the following conditions:
Figure BDA0003069323930000112
wherein, Delta theta2Is the peak-to-peak variation in absolute steering wheel angle over more than one mechanical revolution, and RredIs the reduction ratio of the reduction gear 4.
It should be noted that the parameter NturnsHave a physical meaning. It corresponds to the first calculation signal
Figure BDA0003069323930000113
On which will be the number of mechanical steering wheel turns of the double shot. Thus, there is a constraint Nturns≥Δθ2/360, which means that the first calculation signal
Figure BDA0003069323930000114
Must be at least greater than the peak-to-peak variation in the measurement defined by the specification of the application. Furthermore, NturnsNot necessarily an integer.
It is believed that the subject matter of the present invention uses vernier effect techniques to construct the first calculated signal of the steering wheel angle
Figure BDA0003069323930000115
Another important point to note is to have multiple mechanical rotations (N)turns> 1)) is required to have a non-integer reduction ratio Rred. This can be understood using the constraints already defined above:
Figure BDA0003069323930000116
wherein N is1，p1，N2，p2Is an integer
When N is presentturns(> 1), it can be seen that the only way to satisfy this constraint is to have a non-integer reduction ratio Rred. This is often the case in power assisted steering. In order to remain absolute over several turns of the steering wheel (once the system is powered on), current steering wheel angle sensors use gears to be able to distinguish between mechanical turns. These additional gears are expensive. Thanks to the proposed invention, it is possible to manufacture a multiturn sensor without adding any gear, since the subject of the invention reuses the already available gear of the reduction gear 4 of the electric motor 3.
According to an advantageous variant, the weighting factor q1And q is2The optimum values of (a) are as follows:
if N is present2＜N1RredThen, then
Figure BDA0003069323930000121
If N is present2>N1RredThen, then
Figure BDA0003069323930000122
Wherein σ1Is a typical magnitude of error for the first angular position sensor, and σ2Is a typical magnitude of error for the second angular position sensor.
According to a second variant embodiment, based on the signal α1、α2And alpha3To calculate a first signal
Figure BDA0003069323930000123
As follows. First, an intermediate signal is calculated
Figure BDA0003069323930000124
As follows:
Figure BDA0003069323930000125
wherein the content of the first and second substances,
Figure BDA0003069323930000126
Figure BDA0003069323930000127
where pgcd is the "greatest common denominator". Parameter c2And c3Are numerical coefficients chosen by the designer and that must satisfy the following conditions:
Figure BDA0003069323930000128
it can be proved that the intermediate signal
Figure BDA0003069323930000131
With an AND signal alpha2The same absolute measurement error (in geometric degrees) but with a ratio signal a2Is (equal to N)2) Small weekPeriodic (equal to N)23). In other words, the signal α is reduced due to its periodicity3So that a can be reduced2Relative measurement error (in electrical degrees). Due to this improvement, it is in fact simpler to put α in the second step1And
Figure BDA0003069323930000132
rather than with alpha2Are combined to obtain
Figure BDA0003069323930000133
This calculation is defined as follows:
Figure BDA0003069323930000134
wherein the content of the first and second substances,
Figure BDA0003069323930000135
wherein the content of the first and second substances,
Figure BDA0003069323930000136
and
Figure BDA0003069323930000137
is a fixed weighting factor that the designer can choose to minimize the sensor error. The simplest selection
Figure BDA0003069323930000138
Defining signals that are not always optimal in terms of noise suppression and measurement error
Figure BDA0003069323930000139
As a function of (c). Parameter(s)
Figure BDA00030693239300001310
And
Figure BDA00030693239300001311
are numerical coefficients chosen by the designer and that must satisfy the following conditions:
Figure BDA00030693239300001312
wherein, Delta theta2Is the peak-to-peak variation in absolute steering wheel angle over more than one mechanical revolution, and RredIs the reduction ratio of the reduction gear 4.
When all the above conditions are met for a given embodiment, it can be demonstrated that the first calculation signal is for the closest measurement error and the closest slope sign
Figure BDA00030693239300001313
Equal to more than one turn of the absolute steering wheel angle theta2I.e. by
Figure BDA00030693239300001314
The processing unit 15 obtains an angle-weighted summation of the different available signals to generate a second calculation signal proportional to the torque T
Figure BDA00030693239300001315
The angle weighted summation of the signals is a linear combination of the signals, where the final result is placed in the interval [ -180; 180 degree]In (or placed in the interval [ - π; π according to the choice of the angle unit]In (1).
The processing unit 15 acquires the third signal alpha3And from the first signal alpha1A second signal alpha2And a first calculation signal
Figure BDA00030693239300001316
An angle weighted sum of one of the acquired signals.
According to a first variant embodiment, shown in figure 2, based on the third signal a3And a first signal alpha1To calculate a second calculation signal
Figure BDA0003069323930000141
Second calculation signal
Figure BDA0003069323930000142
Comprises the following steps:
Figure BDA0003069323930000143
wherein f issIs the aforementioned mathematical sawtooth function with a slope equal to 1, alpha1Is a signal generated by a first angular position sensor 11, alpha3Is the signal generated by the third angular position sensor 13 and G is the stiffness of the torsion bar 7, and wherein k1、k3Are numerical coefficients chosen by the designer and that must satisfy the following conditions:
Figure BDA0003069323930000144
wherein, Delta thetashiftIs the peak-to-peak variation in angular deformation of the torsion bar 7.
According to a second variant embodiment, shown in figure 3, based on the third signal a3And a second signal alpha2To calculate a second calculation signal
Figure BDA0003069323930000145
Second calculation signal
Figure BDA0003069323930000146
Comprises the following steps:
Figure BDA0003069323930000147
wherein f issIs the aforementioned mathematical sawtooth function with a slope equal to 1, alpha2Is the signal generated by the second angular position sensor 12, alpha3Is a signal generated by the third angular position sensor 13, and G is the stiffness of the torsion bar 7, andwherein k is2、k3Are numerical coefficients chosen by the designer and that must satisfy the following conditions:
Figure BDA0003069323930000148
wherein, Delta thetashiftIs the peak-to-peak variation in angular deformation of the torsion bar 7.
According to a third variant embodiment, shown in fig. 4, based on the third signal α3And a first calculation signal
Figure BDA0003069323930000149
To calculate a second calculation signal
Figure BDA00030693239300001410
Second calculation signal
Figure BDA00030693239300001411
Comprises the following steps:
Figure BDA00030693239300001412
wherein f issIs the aforementioned mathematical sawtooth function with a slope equal to 1,
Figure BDA0003069323930000151
is the first calculation signal, alpha3Is the signal generated by the third angular position sensor 13 and G is the stiffness of the torsion bar 7, and wherein k3Are numerical coefficients chosen by the designer and that must satisfy the following conditions:
Figure BDA0003069323930000152
wherein, Delta thetashiftIs the peak-to-peak variation in angular deformation of the torsion bar 7.
When all of the above conditions are satisfied (for a given variant embodiment), the most pertinent is toThe approximated measurement error and the closest slope sign can prove that the second calculation signal
Figure BDA0003069323930000153
Equal to the applied torque, or:
Figure BDA0003069323930000154
as is apparent from the foregoing description, the torque and reference steering wheel angle are determined by "physical" sensors of torque and steering wheel angle. In particular, based on the first signal α generated by the first angular position sensor 111And a second signal a generated by a second angular position sensor 122To determine the absolute steering wheel angle theta over more than one mechanical turn2And on the basis of a third signal alpha generated by a third angular position sensor 133And from the first signal alpha1A second signal alpha2And a first calculation signal
Figure BDA0003069323930000155
Determines the applied torque T from one of the signals acquired.
The first angular position sensor 11, the second angular position sensor 12 and the third angular position sensor 13 are angular position sensors of any type known per se with a Ni antipole (Ni being an integer greater than or equal to 1). For example, the first, second and/or third angular position sensors 11, 12, 13 are hall effect position sensors, magnetoresistive sensors, flux gate sensors, inductive sensors, eddy current sensors or variable reluctance sensors or combinations of sensors.
The complex and expensive sensors of the prior art are replaced by much simpler angular position sensors and specific signal processing. This replacement has been made possible by judicious reuse of the first signal of the first angular position sensor 11, which is already available on most power steering, and this ensures control of the electric motor 3 of the power steering mechanism, and also by judicious reuse of the reduction gear of the electric motor, which is already available on all power steering. Furthermore, the detection system 1 according to the invention does not require any initialization at start-up and does not require any continuous control system. Once the angular position sensor is energized, the first calculation signal and the second calculation signal are available. These two calculation signals are obtained without first performing a movement of the steering mechanism.
Fig. 5 to 7 illustrate the subject of the invention by performing numerical calculations according to the above principle, with the following dimensions: delta theta2＝1000°mec，ΔT＝21N.m，G＝3N.m/°，Rred＝61/3，N1＝1，N2＝10，N3＝20，p1＝1，p2＝-2，Nturns＝3，k2＝-2，k3＝1，q1＝0，q 20. The second modified embodiment has been used for calculation of torque.
Fig. 5 shows the first signals a generated by the three angular position sensors 11, 12, 13, respectively, as a function of the reference steering wheel angle in an ideal case without noise and measurement errors1A second signal alpha2And a third signal alpha3In the form of (1).
FIG. 6 shows a first calculated signal proportional to the absolute steering wheel angle over more than one mechanical revolution for different torque values
Figure BDA0003069323930000161
First calculation signal
Figure BDA0003069323930000162
Linearly dependent on absolute steering wheel angle theta over more than one mechanical turn2And is completely insensitive to torque.
FIG. 7 shows a second calculated signal proportional to torque for different values of steering wheel angle
Figure BDA0003069323930000163
Second calculation signal
Figure BDA0003069323930000164
Linearly dependent on the applied torque T and completely insensitive to the steering wheel angle.
Such a numerical model makes it possible to prove that the first calculated signal and the second calculated angle correspond respectively to the absolute steering wheel angle θ over more than one mechanical revolution2And the applied torque T.
It should be noted that these figures show simulations performed in the absence of noise. In the presence of noise, other simulations were also performed. These simulations have shown that the invention is robust to this noise, including in the first saw-tooth signal α1A second saw-tooth signal alpha2And a third saw-tooth signal alpha3Mechanical angles with discontinuities. That is, the noise present at the input is transmitted at the output without being substantially amplified. In judicious selection of weighting coefficients q1And q is2The use of the vernier effect can even greatly improve the signal-to-noise ratio at the output.
It should be considered that the detection system according to the invention is designed based on input data from specifications of each envisaged application. Thus, the peak-to-peak change in steering wheel angle and torque Δ θ2And Δ T corresponds to the range of the measurement system required by the specification. Of course, these input data may have different values depending on the desired application.
According to a particularly advantageous embodiment, the processing unit 15 verifies whether the set of measurement signals and calculation signals belongs to a set of acceptable values. If this is not the case, the processing unit 15 transmits an alarm signal when the set of measurement signals and calculation signals does not belong to the set of acceptable values. This method makes it possible to detect abnormally large measurement errors of some kind. For example, the processing unit may calculate the following signal D:
Figure BDA0003069323930000171
based on design parameters, canTo define the following threshold Dlim：
Figure BDA0003069323930000172
Where λ is a fixed coefficient between 0 and 1, chosen by the designer, and makes it possible to adjust the severity of the diagnostic system. Thus, if the processing unit detects the following event at any time:
D>Dlim
the processing unit 15 transmits an alarm signal.
According to a variant embodiment, the second angular position sensor 12 and the third angular position sensor 13 are eddy current position sensors. Fig. 8 exemplarily shows the second angular position sensor 12 and the third angular position sensor 13 provided on either side of the torsion bar 7. Each angular position sensor 12, 13 comprises, on the one hand, a target member 12 firmly mounted on each side of the torsion bar 7, respectively1、131And detection probes 12 placed in correspondence with the respective targets, respectively, externally with respect to the torsion bar 72、132。
According to an advantageous variant embodiment shown in fig. 9, the second eddy current angular position sensor 12 and the third eddy current angular position sensor 13 have a target 12 placed on both sensors1、131I.e. at the level of the torsion bar 7, with a common detection probe 23 in between. The common detection probe 23 comprises a common support plate for the windings of the second angular position sensor 12 and the third angular position sensor 13. The generation of the windings of the two angular position sensors 12, 13 makes it possible to reduce the manufacturing costs by using a single circuit backing. The cross talk between the two angular position sensors may be used as N3Different number of N2Either by pole pairs or by interposing conductive and/or magnetic material between the windings to allow the magnetic fields of the two sensors to decouple.
The invention is not limited to the examples described and represented, since various modifications can be made thereto without departing from the scope thereof.

Claims (12)

1. A detection system for a steering mechanism (2) of a vehicle, which allows to measure the torque (T) and the absolute steering wheel angle (θ) over more than one mechanical turn2) -the steering mechanism comprising a torsion bar (7) and being equipped with an electric motor (3), -the electric motor (3) being provided with a reduction gear (4), -the detection system comprising:
-a first angular position sensor (11) having N1 pairs of poles, where N1 is an integer greater than or equal to 1, said first angular position sensor (11) measuring the angle of the electric motor (3) and delivering a first signal (α)1)；
-a second angular position sensor (12) having N2 pairs of poles, where N2 is an integer greater than or equal to 1, said second angular position sensor (12) measuring the angle of the steering mechanism between the reduction gear (4) and the first side of the torsion bar (7), said second angular position sensor delivering a second signal (α)2)；
-a third angular position sensor (13) having N3 pairs of poles, where N3 is an integer greater than or equal to 1, the third angular position sensor (13) measuring the angle of the steering mechanism on the second side of the torsion bar (7) and transmitting a third signal (α)3) The second side being opposite the first side; and
-a processing unit (15), said processing unit (15) being based on at least said first signal (a), on the one hand1) And said second signal (alpha)2) Performing a vernier calculation to generate an absolute steering wheel angle (θ) over said more than one mechanical turn2) Proportional first calculation signal
Figure FDA0003069323920000011
And, on the other hand, the processing unit (15) processes the third signal (α)3) And from said first signal (α)1) The second signal (alpha)2) And the first calculation signal
Figure FDA0003069323920000012
In (C) acquisitionIs subjected to an angle-weighted summation to generate a second calculation signal proportional to the torque (T)
Figure FDA0003069323920000013
2. The system according to the preceding claim, wherein the processing unit (15) considers the first calculation signal
Figure FDA0003069323920000014
Absolute steering wheel angle (theta) over mechanical rotation corresponding to the more than one turn2) And said second calculation signal
Figure FDA0003069323920000015
Corresponding to the applied torque (T).
3. System according to one of the preceding claims, wherein the processing unit (15) performs a cursor calculation to generate the first calculation signal
Figure FDA0003069323920000016
The first calculation signal
Figure FDA0003069323920000017
Comprises the following steps:
Figure FDA0003069323920000018
wherein, Θ is fs(p1α1+p2α2)
And, fsIs a mathematical sawtooth function with a slope equal to 1, where q1And q is2Is selected as a fixed weighting coefficient, and alpha1Is a signal, alpha, generated by said first angular position sensor (11)2Is generated by the second angular position sensor (12)A signal;
and wherein p is1、p2And NturnsAre numerical coefficients that are selected and must satisfy the following conditions:
Figure FDA0003069323920000021
wherein, Delta theta2Is the peak-to-peak variation of the absolute steering wheel angle over said more than one mechanical revolution, and RredIs the reduction ratio of the reduction gear (4).
4. The system of claim 3, wherein the weighting factor q1And q is2As follows:
if N is present2<N1RredThen, then
Figure FDA0003069323920000022
If N is present2>N1RredThen, then
Figure FDA0003069323920000023
Wherein σ1Is a typical magnitude of the error of said first angular position sensor, and σ2Is a typical magnitude of error for the second angular position sensor.
5. System according to one of claims 1 or 2, wherein the processing unit (15) performs a cursor calculation to generate the first calculation signal
Figure FDA0003069323920000024
The first calculation signal
Figure FDA0003069323920000025
Comprises the following steps:
Figure FDA0003069323920000026
wherein the content of the first and second substances,
Figure FDA0003069323920000027
Figure FDA0003069323920000028
Figure FDA0003069323920000031
Figure FDA0003069323920000032
and, fsIs a mathematical sawtooth function with a slope equal to 1, where pgcd is the "maximum common denominator" operator, where,
Figure FDA0003069323920000033
and
Figure FDA0003069323920000034
is selected as a fixed weighting coefficient, and1is a signal, alpha, generated by said first angular position sensor (11)2Is a signal, a, generated by the second angular position sensor (12)3Is a signal generated by the third angular position sensor (13);
and wherein c2、c3、
Figure FDA0003069323920000035
And
Figure FDA0003069323920000036
are numerical coefficients that are chosen and must satisfy the following conditions:
Figure FDA0003069323920000037
wherein, Delta theta2Is the peak-to-peak variation of the absolute steering wheel angle over said more than one mechanical revolution, and RredIs the reduction ratio of the reduction gear (4).
6. System according to one of the preceding claims, wherein the second calculation signal
Figure FDA0003069323920000038
Comprises the following steps:
Figure FDA0003069323920000039
wherein f issIs a mathematical sawtooth function with a slope equal to 1, alpha2Is a signal, a, generated by the second angular position sensor (12)3Is a signal generated by the third angular position sensor (13), and G is the stiffness of the torsion bar (7), and wherein k2、k3Are numerical coefficients that are chosen and must satisfy the following conditions:
Figure FDA0003069323920000041
wherein, Delta thetashiftIs the peak-to-peak variation of the angular deformation of the torsion bar.
7. System according to one of claims 1 to 5, wherein the second calculationSignal
Figure FDA0003069323920000042
Comprises the following steps:
Figure FDA0003069323920000043
wherein f issIs a mathematical sawtooth function with a slope equal to 1, alpha1Is a signal, alpha, generated by said first angular position sensor (11)3Is a signal generated by the third angular position sensor (13), and G is the stiffness of the torsion bar (7), and wherein k1、k3Are numerical coefficients that are chosen and must satisfy the following conditions:
Figure FDA0003069323920000044
wherein, Delta thetashiftIs the peak-to-peak variation of the angular deformation of the torsion bar.
8. System according to one of claims 1 to 5, wherein the second calculation signal
Figure FDA0003069323920000045
Comprises the following steps:
Figure FDA0003069323920000046
wherein f issIs a mathematical sawtooth function with a slope equal to 1,
Figure FDA0003069323920000047
is the first calculation signal, alpha3Is a signal generated by the third angular position sensor (13), and G is the stiffness of the torsion bar (7), and wherein k3Are selected and must satisfy the following conditionsNumerical coefficient:
Figure FDA0003069323920000048
wherein, Delta thetashiftIs the peak-to-peak variation of the angular deformation of the torsion bar (7).
9. The system according to one of the preceding claims, wherein the processing unit (15) verifies whether the set of measurement signals and calculation signals belongs to a set of acceptable values, the processing unit (15) transmitting an alarm signal when the set of values does not belong to the set of acceptable values.
10. The system according to one of the preceding claims, characterized in that the first angular position sensor (11), the second angular position sensor (12) and/or the third angular position sensor (13) are hall effect position sensors, magneto-resistive sensors, fluxgate sensors, inductive sensors, eddy current sensors or variable magneto-resistive sensors.
11. The system according to one of the preceding claims, characterized in that the second angular position sensor (12) and the third angular position sensor (13) are eddy current position sensors or a combination of sensors comprising a common detection probe (23), the common detection probe (23) comprising a common support plate for the windings of the second angular position sensor (12) and the third angular position sensor (13).
12. Steering mechanism equipped with a detection system (1) according to one of claims 1 to 11, said steering mechanism being dependent on the absolute steering wheel angle (Θ) over said more than one mechanical turn2) And the applied torque (T) to execute the steering command.
CN201980075777.5A 2018-11-15 2019-11-14 Detection system for vehicle steering capable of measuring torque and multi-turn absolute steering wheel angle Pending CN113167597A (en)

Applications Claiming Priority (3)

Application Number Priority Date Filing Date Title
FR1860526A FR3088717B1 (en) 2018-11-15 2018-11-15 DETECTION SYSTEM FOR STEERING OF A VEHICLE ALLOWING THE MEASUREMENT OF TORQUE AND ABSOLUTE MULTI-TURN STEERING ANGLE
FR1860526 2018-11-15
PCT/FR2019/052703 WO2020099790A1 (en) 2018-11-15 2019-11-14 Detection system for the steering of a vehicle making it possible to measure the torque and the multi-turn absolute steering-wheel angle

Publications (1)

Publication Number Publication Date
CN113167597A true CN113167597A (en) 2021-07-23

Family

ID=65861415

Family Applications (1)

Application Number Title Priority Date Filing Date
CN201980075777.5A Pending CN113167597A (en) 2018-11-15 2019-11-14 Detection system for vehicle steering capable of measuring torque and multi-turn absolute steering wheel angle

Country Status (4)

Country Link
CN (1) CN113167597A (en)
DE (1) DE112019005731T5 (en)
FR (1) FR3088717B1 (en)
WO (1) WO2020099790A1 (en)

Families Citing this family (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
GB2613340A (en) * 2021-11-26 2023-06-07 Paragraf Ltd Graphene based rotational transducer and torque sensor
DE102022102110A1 (en) 2022-01-31 2023-08-03 Schaeffler Technologies AG & Co. KG Steering unit for a steer-by-wire steering system and method for steering angle detection
DE102022208801A1 (en) * 2022-08-25 2024-03-07 Robert Bosch Gesellschaft mit beschränkter Haftung Sensor arrangement and method for detecting a rotational movement of a body that can be rotated about an axis of rotation

Citations (22)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US6354396B1 (en) * 1999-02-05 2002-03-12 Trw Lucasvarity Electric Steering Ltd. Electric power assisted steering systems
JP2003267234A (en) * 2002-03-19 2003-09-25 Koyo Seiko Co Ltd Electric power steering device
DE102005059883A1 (en) * 2005-12-15 2007-06-21 Zf Lenksysteme Gmbh Steering system for motor vehicle has signal of first angle sensor divided over its maximum possible scope into number of signal periods
WO2008077861A1 (en) * 2006-12-22 2008-07-03 Zf Lenksysteme Gmbh Steering angle and torque sensor in a power steering system of a motor vehicle
CN101353051A (en) * 2007-07-25 2009-01-28 株式会社电装 Power steering apparatus having failure detection device for rotation angle sensors
DE102009039764A1 (en) * 2009-09-02 2011-03-03 Bayerische Motoren Werke Aktiengesellschaft System for determining steering angle provided by driver for steering system of vehicle, has measuring device provided with poles pairs, where poles-pairs and speed ratio are selected such that wheel-rotation angle range is covered
CN102264593A (en) * 2008-12-26 2011-11-30 丰田自动车株式会社 Driving support system of vehicle
DE102010053596A1 (en) * 2010-12-07 2012-06-14 Leopold Kostal Gmbh & Co. Kg Device for measuring rotation angle of driving wheel, has rotational angle sensors that detect rotating movements of driving wheel, and trigger sensor that produces trigger signal in defined position of driving wheel
CN102612456A (en) * 2010-04-14 2012-07-25 丰田自动车株式会社 Vehicle control device
US20130166142A1 (en) * 2011-12-22 2013-06-27 Mando Corporation Electric power steering system and method for verifying steering angle thereof
CN103764484A (en) * 2011-08-24 2014-04-30 大陆-特韦斯贸易合伙股份公司及两合公司 Combined steering torque-steering angle sensor
FR3018113A1 (en) * 2014-02-28 2015-09-04 Electricfil Automotive MAGNETIC SENSOR FOR DETERMINING THE RELATIVE POSITION BETWEEN A MAGNETIC TARGET AND A MEASURING SYSTEM
US20160257336A1 (en) * 2014-09-02 2016-09-08 Nsk Ltd. Electric power steering apparatus
EP3090921A1 (en) * 2015-02-19 2016-11-09 NSK Ltd. Vehicle steering angle detection apparatus, and electric power steering apparatus equipped with same
CN106170430A (en) * 2014-03-25 2016-11-30 日本精工株式会社 Electric power-assisted steering apparatus
CN106415209A (en) * 2014-08-08 2017-02-15 日本精工株式会社 Angle detection device, and motor, torque sensor, electric power steering apparatus, and automobile provided with said angle detection device
CN106573648A (en) * 2014-06-25 2017-04-19 Trw有限公司 An electric power assisted steering system
CN106679560A (en) * 2016-12-02 2017-05-17 安徽沃巴弗电子科技有限公司 Electromagnetic induction type torque angle sensor
CN107923769A (en) * 2015-07-21 2018-04-17 伊莱克特里克菲儿汽车公司 Sensor for the absolute position for measuring moving parts
CN107949985A (en) * 2015-08-12 2018-04-20 日本精工株式会社 Controller for motor, electric power-assisted steering apparatus and vehicle
WO2018108783A2 (en) * 2016-12-12 2018-06-21 Idt Europe Gmbh Ultra-thin combined inductive torque and angle sensor for steering wheel position sensing
US20180208239A1 (en) * 2014-06-25 2018-07-26 Trw Limited An Electric Power Assisted Steering System

Family Cites Families (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
FR2872896B1 (en) 2004-07-09 2008-01-11 Moving Magnet Tech POSITION SENSOR, PARTICULARLY FOR MEASURING THE TORSION OF A STEERING COLUMN
FR2964190B1 (en) 2010-08-24 2013-02-08 Moving Magnet Tech MAGNETIC DETECTION DEVICE WITH ABSOLUTE MULTITOUR POSITION

Patent Citations (23)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US6354396B1 (en) * 1999-02-05 2002-03-12 Trw Lucasvarity Electric Steering Ltd. Electric power assisted steering systems
JP2003267234A (en) * 2002-03-19 2003-09-25 Koyo Seiko Co Ltd Electric power steering device
DE102005059883A1 (en) * 2005-12-15 2007-06-21 Zf Lenksysteme Gmbh Steering system for motor vehicle has signal of first angle sensor divided over its maximum possible scope into number of signal periods
WO2008077861A1 (en) * 2006-12-22 2008-07-03 Zf Lenksysteme Gmbh Steering angle and torque sensor in a power steering system of a motor vehicle
CN101353051A (en) * 2007-07-25 2009-01-28 株式会社电装 Power steering apparatus having failure detection device for rotation angle sensors
CN102264593A (en) * 2008-12-26 2011-11-30 丰田自动车株式会社 Driving support system of vehicle
DE102009039764A1 (en) * 2009-09-02 2011-03-03 Bayerische Motoren Werke Aktiengesellschaft System for determining steering angle provided by driver for steering system of vehicle, has measuring device provided with poles pairs, where poles-pairs and speed ratio are selected such that wheel-rotation angle range is covered
CN102612456A (en) * 2010-04-14 2012-07-25 丰田自动车株式会社 Vehicle control device
DE102010053596A1 (en) * 2010-12-07 2012-06-14 Leopold Kostal Gmbh & Co. Kg Device for measuring rotation angle of driving wheel, has rotational angle sensors that detect rotating movements of driving wheel, and trigger sensor that produces trigger signal in defined position of driving wheel
CN103764484A (en) * 2011-08-24 2014-04-30 大陆-特韦斯贸易合伙股份公司及两合公司 Combined steering torque-steering angle sensor
US20130166142A1 (en) * 2011-12-22 2013-06-27 Mando Corporation Electric power steering system and method for verifying steering angle thereof
FR3018113A1 (en) * 2014-02-28 2015-09-04 Electricfil Automotive MAGNETIC SENSOR FOR DETERMINING THE RELATIVE POSITION BETWEEN A MAGNETIC TARGET AND A MEASURING SYSTEM
CN106170430A (en) * 2014-03-25 2016-11-30 日本精工株式会社 Electric power-assisted steering apparatus
CN106573648A (en) * 2014-06-25 2017-04-19 Trw有限公司 An electric power assisted steering system
US20180208239A1 (en) * 2014-06-25 2018-07-26 Trw Limited An Electric Power Assisted Steering System
CN106415209A (en) * 2014-08-08 2017-02-15 日本精工株式会社 Angle detection device, and motor, torque sensor, electric power steering apparatus, and automobile provided with said angle detection device
US20160257336A1 (en) * 2014-09-02 2016-09-08 Nsk Ltd. Electric power steering apparatus
EP3090921A1 (en) * 2015-02-19 2016-11-09 NSK Ltd. Vehicle steering angle detection apparatus, and electric power steering apparatus equipped with same
US20160362128A1 (en) * 2015-02-19 2016-12-15 Nsk Ltd. Steering angle detecting apparatus for vehicles and electric power steering apparatus equipped therewith
CN107923769A (en) * 2015-07-21 2018-04-17 伊莱克特里克菲儿汽车公司 Sensor for the absolute position for measuring moving parts
CN107949985A (en) * 2015-08-12 2018-04-20 日本精工株式会社 Controller for motor, electric power-assisted steering apparatus and vehicle
CN106679560A (en) * 2016-12-02 2017-05-17 安徽沃巴弗电子科技有限公司 Electromagnetic induction type torque angle sensor
WO2018108783A2 (en) * 2016-12-12 2018-06-21 Idt Europe Gmbh Ultra-thin combined inductive torque and angle sensor for steering wheel position sensing

Non-Patent Citations (1)

* Cited by examiner, † Cited by third party
Title
罗玲 等: ""Halbach永磁阵列无刷直流电机转矩的解析计算和分析"", 《电工技术学报》, vol. 32, no. 16, 25 August 2017 (2017-08-25), pages 124 - 135 *

Also Published As

Publication number Publication date
WO2020099790A1 (en) 2020-05-22
FR3088717B1 (en) 2021-09-17
DE112019005731T5 (en) 2021-09-09
FR3088717A1 (en) 2020-05-22

Similar Documents

Publication Publication Date Title
CN103256883B (en) Also the angular sensor of absolute rotation angle can be determined when multiple rotary
CN113167597A (en) Detection system for vehicle steering capable of measuring torque and multi-turn absolute steering wheel angle
JP5679136B2 (en) Rotation angle detection device and electric power steering device provided with rotation angle detection device
KR101721087B1 (en) Multi-periodic absolute position sensor
KR101272699B1 (en) Apparatus for sensing steering angle and sensing method of the same
JP6359079B2 (en) Hall sensor insensitive to external magnetic field
US20080307873A1 (en) Steering Angle Sensing Apparatus and Method Thereof
KR101829057B1 (en) Angle sensor
US11248971B2 (en) Magnetic field torque and/or angle sensor
WO2005028993A1 (en) Steering angle sensor
EP2093538B1 (en) Rotation angle detection device and rotation angle detection method
JP2017015696A (en) Relative angle detection device, torque sensor, electrically-driven power steering device and vehicle
US20170183034A1 (en) Sensing device, sensing system and steering system
JP3898610B2 (en) Torque sensor
EP1910155A1 (en) Steering angle sensing apparatus and method thereof
JP5545121B2 (en) Rotation angle / torque sensor
CN112867662B (en) Angle sensor with two-pole magnet for motor vehicle steering system
CN110006466B (en) Arithmetic processing device, angle sensor, and power steering device
JP5170457B2 (en) Angle detector
US6851325B2 (en) DSP based algorithm for non-contacting torque sensor
JP5950459B2 (en) Power steering device
US6935194B2 (en) Dual resolver device
CN107466363B (en) Sensor for measuring the torque of a drive shaft
US20220260438A1 (en) Sensor assembly for sensing a steering torque and an absolute angular position, and sensor device having said sensor assembly
JP2009300445A (en) Rotation speed sensor and rotation position/speed sensor

Legal Events

Date Code Title Description
PB01 Publication
PB01 Publication
SE01 Entry into force of request for substantive examination
SE01 Entry into force of request for substantive examination