DE102019206506A1 - Classification of road anomalies - Google Patents

Abstract

The invention relates to a method for dynamically controlling at least one actuator for setting tension damping forces and pressure damping forces of a vibration damper on the basis of a classification of roadway anomalies, the actuator being in coordination between an average setting of the actuator when overcoming roadway anomalies and a force requirement on the actuator adjusted based on the classification. A motor vehicle for carrying out the method is also provided.

Description

The invention relates to a method for dynamically controlling at least one actuator of a vibration damper on the basis of a classification of roadway anomalies, as well as a motor vehicle for carrying out the method.

When driving over bumps in the road, vibrations of the wheels are generated, as a result of which the contact force of the corresponding vehicle with respect to the road varies. This can reduce the controllability of the vehicle. In order to let the vibrations subside as quickly as possible, vibration dampers are provided in the wheel suspension.

Vehicles often include active, semi- and / or adaptive suspension systems for the wheels in order to control vertical movements of the wheels in particular. The suspension features, such as Damping and stiffness, selectively adapted to abnormal road conditions. An adaptive suspension system is e.g. Continuously Controlled Damping (CCD) from FORD. In order to provide the greatest possible comfort for the vehicle occupants, the damping of the vibration dampers is set to a relatively low level. However, damping settings that are set low lead to higher vertical loads if the vehicle has an abnormality in the road, including a deviation from the evenness of a road surface, for example a bulge or the like. is to be understood, drives through and hits the edge of the road anomaly, which delimits it in the direction of travel from the road behind it.

To set a degree of damping, actuators are used to regulate damping forces. These actuators can be valves, for example, which is why they are often generally referred to as valves. To regulate damper forces that counteract tensile forces, pull actuators or pull valves are arranged in the vibration dampers. To regulate damping forces that counteract pressure forces, pressure actuators or pressure valves are arranged in the vibration dampers. In the pamphlet DE 10 2014 204 519 A1 it is disclosed that a vibration damper can comprise at least one pull valve and one pressure valve, which can be adjusted by means of actuators in different stages or continuously between hard and soft settings.

Conventional methods for camera-based control of vibration dampers do not sufficiently differentiate between different orders of magnitude of the manifestations of roadway anomalies. This leads to a lack of control over the vehicle and reduces travel comfort. The task is to further increase the driving comfort when passing road anomalies.

This object is achieved by a method with the features of claim 1. Further advantageous embodiments and refinements of the invention emerge from the independent claim and the subclaims, the figures and the exemplary embodiments. The said embodiments and subjects of the claims can be combined with one another in an advantageous manner.

• - Bewegen des Fahrzeugs,
• - Erfassen einer Fahrbahnanomalität in der in Bewegungsrichtung des Fahrzeugs vorausliegenden Fahrbahnoberfläche,
• - Klassifizieren der Fahrbahnanomalität in Bezug auf die senkrechte Dimension h der Fahrbahnanomalität, den Gradienten G der Flanken der Fahrbahnanomalität sowie die Geschwindigkeit v des Fahrzeugs,
• - Berechnen einer Kraftanforderung F_R an das Stellglied, die der Klassifizierung der Fahrbahnanomalität entspricht,
• - Abstimmen der Kraftanforderung F_R mit einer aktuellen Einstellung Fs des Stellglieds,
• - Verstellen des Stellglieds in Abhängigkeit von der Klassifizierung der Fahrbahnanomalität.

A first aspect of the invention relates to a method for controlling a semi-active suspension of at least one wheel of a vehicle, which comprises an arrangement of a vibration damper with at least one actuator that can be adjusted in different stages or continuously between a hardest and a softest setting by means of at least one actuator , and wherein the vehicle has at least one sensor for detecting roadway anomalies and at least one control device connected to the sensor and the actuator, with the steps:

• - moving the vehicle,
• - Detection of a road anomaly in the road surface ahead in the direction of movement of the vehicle,
• - Classification of the road anomaly in relation to the vertical dimension h of the road anomaly, the gradient G of the edges of the road anomaly and the speed v of the vehicle,
• - Calculation of a force requirement F _R on the actuator that corresponds to the classification of the road anomaly,
• - Matching the force requirement F _R with a current setting Fs of the actuator,
• - Adjustment of the actuator depending on the classification of the road anomaly.

The method according to the invention is advantageous because the classification of a detected road anomaly enables the vibration damping to be adapted to the condition of the road surface. Advantageously, the characteristics of roadway anomalies and the speed of the motor vehicle are taken into account, since different road bumps have different effects on the motor vehicle at different speeds. The method also advantageously allows a gradual transition between different degrees of hardness of the settings of the said actuators of a vibration damper. This protects the material of the motor vehicle and for the Occupants of the motor vehicle provided greater comfort.

A roadway is e.g. an asphalt road, a concrete road, a paved road, a dirt road, or the like. The method is not only intended for asphalt roads, but for any type of surface on which a vehicle, especially a motor vehicle, can move. The procedure can also be carried out with active suspensions.

The road anomaly here is a localized increase in the road surface, e.g. in the form of a bulge in an asphalt surface, a hump, a bump or a road threshold.

The vertical dimension h lane relates to the height of the lane anomaly. The gradient G of the flanks relates to the degree of inclination on the rising flank of the road anomaly. The speed v of the vehicle relates to the distance covered per unit of time with which the vehicle is moving towards the abnormal lane.

The force requirement F _R is preferably coordinated with the properties of the vehicle. This is advantageous because every vehicle or vehicle type has specific properties in terms of material and components.

durchgeführt wird, wobei R ein Ausdruck für die Klassifizierung ist und n1 - n7 fahrzeug- und situationsbezogene Variablen sind. Dem Fachmann sind die Variablen bekannt, so dass er sie in Abhängigkeit vom Fahrzeugtyp und bestimmten Fahrsituationen einsetzt. Der Ausdruck R ist entsprechend den Werten von Höhe, Gradient und Geschwindigkeit verschieden groß; die Größe des Wertes von R gilt als Maß für die weiteren notwendigen Einstellungen. Dabei werden bestimmte Größen von R als Schwellenwerte definiert, ab denen verschiedene Verstellungen der Stellglieder vorgenommen werden. Besonders bevorzugt muss die Höhe h einen einer Mindesthöhe entsprechenden Schwellenwert erreichen (h ≥ hmin). Weiterhin ist bevorzugt, dass der Gradient G zwischen einem minimalen und maximalen Gradienten liegen (G_min < G < G_max).In a preferred embodiment, the classification is carried out using the formula $$\text{R.}=\left({\text{<figure-callout id="2" label="n" filenames="DE102019206506A1\_0010.png,DE102019206506A1\_0012.png" state="{{state}}">n</figure-callout>}}_{\text{2}}{\text{+ n}}_{\text{7th}}{\text{*H}}^{\text{n1}}\right)*\left({\text{<figure-callout id="3" label="n" filenames="DE102019206506A1\_0009.png,DE102019206506A1\_0010.png" state="{{state}}">n</figure-callout>}}_{\text{3}}\text{+ G}*{\text{n}}_{\text{4th}}\right)*\left({\text{<figure-callout id="5" label="n" filenames="DE102019206506A1\_0010.png,DE102019206506A1\_0011.png" state="{{state}}">n</figure-callout>}}_{\text{5}}\text{+ v}*{\text{n}}_{\text{6th}}\right)$$

is performed, where R is an expression for the classification and n1 - n7 are vehicle and situation-related variables. The person skilled in the art is familiar with the variables so that he can use them as a function of the vehicle type and certain driving situations. The expression R has different sizes according to the values of altitude, gradient and speed; the size of the value of R is used as a measure for the further necessary settings. Certain values of R are defined as threshold values from which various adjustments of the actuators are made. Particularly preferably, the height h must reach a threshold value corresponding to a minimum height (h hmin). It is also preferred that the gradient G lie between a minimum and maximum gradient (G _min <G <G _max ).

verstellt, wobei z eine spezifische Variable des Stellglieds ist.The setting of the actuator is preferred in the method $${\text{F.}}_{\text{RS}}{\text{= F}}_{\text{S.}}{\text{- z * F}}_{\text{R.}}$$

adjusted, where z is a specific variable of the actuator.

The actuator is preferably not adjusted for a classification R below a first threshold value R ₁ .

In the case of a classification R above the first threshold value R ₁ , the actuator is preferably adjusted to a harder setting relative to the average setting during a pulling action, if it is under tension, and to a softer setting relative to the average setting, until a second threshold value R _{2 is reached} adjusted when there is pressure if it is under pressure. The setting is changed in steps or gradual from 0 to 100% relative to the average setting until the classification reaches the second threshold value R ₂ . The step-by-step or gradual adjustment advantageously ensures a gradual transition between easy adjustment and hard adjustment. 100% corresponds to the hardest or softest setting relative to the average setting for pulling or pushing. The actuator is coupled to at least one sensor which, on the basis of acceleration and / or the amount of damping, determines or measures a tensile or compressive effect in the area of the actuator.

It is also preferred if, for a classification R above the second threshold value R _2, the actuator is adjusted to its hardest setting, if it is under tension, and to its softest setting, if it is under pressure, until a third threshold value R. _{3 is} reached. In the case of a classification above the third threshold value R ₃ , the setting of the actuator is preferably not adjusted. The third threshold value R _{3 is selected in} such a way that it corresponds to a particularly high value of at least one parameter, ie the altitude, the gradient or the speed, which is not reached under the roadway conditions that are usually present. This is the case, for example, at a height of 1 m and / or a gradient of 85%. When the third threshold value R ₃ is reached, a malfunction of the sensor for detecting roadway anomalies is therefore assumed, the value is classified as FALSE and the method is not continued. The sensor for detecting roadway anomalies is, for example, a camera, or is based on RADAR, LIDAR, ultrasound, laser, vehicle-to-vehicle communication or other technologies.

The method is not limited to the three threshold values mentioned. It is possible to have any other number of thresholds to control the setting of the actuator depending on the classification of the road anomaly.

In a preferred embodiment, the method is carried out with a vibration damper which comprises at least one tension actuator and at least one pressure actuator.

verstellt, wobei x eine spezifische Variable des Druckstellglieds ist. Ebenfalls besonders bevorzugt wird die Einstellung für das Zugstellglied nach $${\text{F}}_{\text{RZ}}{\text{=FZ+y*F}}_{\text{R}}$$

verstellt, wobei y eine spezifische Variable des Zugstellglieds ist.The setting for the pressure actuator is particularly preferred $${\text{F.}}_{\text{RD}}{\text{= F}}_{\text{D.}}{\text{- x * F}}_{\text{R.}}$$

adjusted, where x is a specific variable of the pressure actuator. The setting for the pull actuator is also particularly preferred $${\text{F.}}_{\text{RZ}}{\text{= FZ + y * F}}_{\text{R.}}$$

adjusted, where y is a specific variable of the pull actuator.

In the method, when the classification is below a first threshold value R _1, the pressure actuator and the tension actuator are preferably not adjusted.

Preferably, with a classification above the first threshold value R ₁ until a second threshold value R _{2 is reached,} the pressure actuator is gradually or gradually into a setting relative to the normal average setting that is 0-100% softer and the tension actuator is set to a setting relative to the normal average setting by one 0 - 100% harder setting adjusted. Advantageously, only slight countermeasures are taken when overcoming relatively small obstacles or low speeds in an energy-saving manner.

For a classification R above the second threshold value R _2, the pressure actuator is preferably adjusted to its softest setting and the tension actuator is adjusted to its hardest setting until a third threshold value R _{3 is} reached. Advantageously, when overcoming relatively large obstacles or high speeds, the material of the vehicle is spared and travel comfort is increased.

For a classification R above a third threshold value R _3, the settings of the push actuator and pull actuator are preferably not adjusted.

A second aspect of the invention relates to a motor vehicle with a semi-active suspension of at least one wheel of a vehicle, which comprises an arrangement of a vibration damper with at least one actuator, which by means of at least one actuator in different stages or continuously between a hardest and a softest setting can be adjusted, and which has at least one sensor for detecting roadway anomalies and at least one control device connected to the sensor and the actuator, the control device being designed to control a method according to the invention.

The advantages of the motor vehicle according to the invention correspond to the advantages of the method according to the invention. In a preferred embodiment, the arrangement of the vibration damper has at least one tension actuator and at least one pressure actuator.

• 1 eine schematische Darstellung einer Ausführungsform der erfindungsgemäßen Anordnung.
• 2 eine schematische Darstellung einer weiteren Ausführungsform der erfindungsgemäßen Anordnung.
• 3 ein Flussdiagramm einer Ausführungsform des erfindungsgemäßen Verfahrens.
• 4 eine schematische Darstellung eines Fahrzeugrades in Annäherung an eine Fahrbahnanomalität zur Illustration des erfindungsgemäßen Verfahrens.
• 5 eine tabellarische Zusammenstellung von Auswölbungen mit unterschiedlichen Parametern und Klassifizierungen.

The invention is explained in more detail with reference to the figures. Show it

• 1 a schematic representation of an embodiment of the arrangement according to the invention.
• 2 a schematic representation of a further embodiment of the arrangement according to the invention.
• 3 a flow chart of an embodiment of the method according to the invention.
• 4th a schematic representation of a vehicle wheel approaching a road anomaly to illustrate the method according to the invention.
• 5 a tabular compilation of bulges with different parameters and classifications.

In one embodiment of the arrangement according to the invention 1 is in 1 one Vibration damper 2 in a training with a cylinder 3 and thus as a single-tube gas pressure vibration damper 2 shown. It is shown as a monotube damper 2 exemplary and not restrictive; two- or three-tube dampers or similar can also be used. be used. The vibration damper 2 is part of a semi-active wheel suspension system of a motor vehicle. The vibration damper 2 has an oil reservoir 4th on that by a first piston 5 spatially from a work space 6th separated but fluid by an actuator 7th is connected to this work space. The actuator 7th assigns actuators 7a on, which are formed, the actuator 7th to adjust the hardness and softness of the actuator in different settings 7th and thus the vibration damper 2 condition.

In a further embodiment of the arrangement according to the invention 1 according to 2 a vibration damper 2 in a training with a cylinder 3 and thus as a single-tube gas pressure vibration damper 2 shown.

It is shown as a monotube damper 2 exemplary and not restrictive; two- or three-tube dampers or similar can also be used. be used. The vibration damper 2 is part of a semi-active wheel suspension system of a motor vehicle. The vibration damper 2 has an oil reservoir 4th on that by a first piston 5 spatially from a work space 6th separated but fluid by a pull actuator 7th and a pressure actuator 8th with this workspace 6th connected is. The pull actuator 7th has an actuator 7a and the pressure actuator 8th an actuator 8a on that for adjusting the actuators 7th , 8th are trained.

By a second piston, the so-called separating piston 9 , is the work space 6th from a gas cushion 10 Cut. The first piston 5 is about a piston rod 11 connected to sprung parts of the corresponding vehicle, especially the body 12 . The cylinder 3 is connected to unsprung parts of the corresponding vehicle, especially a wheel 13 . Further components, not shown, are arranged in the frame of the wheel suspension system between the parts of the vibration damper 2 and the body 12 or the bike 13 can be located.

Part of the arrangement 1 according to 1 and 2 is still a control device 14th . The control device 14th is designed to receive signals from at least one sensor 15th to recieve. The sensor 15th is a camera sensor which is provided to detect a road anomaly lying ahead of the direction of travel of the vehicle. Other and / or further sensors are also possible which are arranged in the area of the vehicle, detect roadway anomalies and transmit them to the control device 14th can transmit, for example ultrasonic sensors, or are based on radar, laser, lidar, vehicle-to-vehicle communication or other technologies. The control device 14th is formed by the sensor or sensors 15th evaluate the transmitted signals and the control commands to the actuators 7a of the pull actuator 7th or. 8a of the pressure actuator 8th to send.

In a method for controlling a semi-active suspension system according to the flow chart of FIG 3 by means of the arrangement 1 according to 2 will be a first step S1 the vehicle is moving on a road. The vehicle thus moves in a certain direction, for example in the forward direction, as shown by the arrow in the illustration 4th indexed. While the vehicle is in motion, the road surface ahead is constantly displayed 19th through the sensor 15th , which is designed as a camera, examined.

In a second step S2 is through the sensor 15th a lane abnormality in the road surface ahead in the direction of movement of the vehicle 19th detected. As in 4th shown, the said road anomaly is a bulge 20th .

The height h has a higher value than a threshold value of the height hmin, which is specified as 2.5 cm, so that the method continues. In a third step S3 will the in S2 captured bulge 20th in relation to the height h of the bulge 20th , the gradient G of the flank 21st the bulge 20th and the speed v of the vehicle by means of the control device 14th classified. In 5 some exemplary values of height h, gradient G and speed v are given in a table, from which the classifications R are determined. The threshold values are chosen here such that the first threshold value R ₁ = 0.5, the second threshold value R ₂ = 5, and a third threshold value R ₃ = 100 ( 5 ).

To classify the bulge 20th the values for the height h (5 cm), the gradient G (30%) and the speed v (30 km / h) are inserted into the formula (I). This is used for the bulge 20th a classification R = 2.25 is determined, which lies between a first threshold value R ₁ and a second threshold value R ₂ . This means that an adjustment of the actuators 7th , 8th triggers, but the classification is not so high that an adjustment is made in the hardest setting of the pull actuator 7th and the softest setting of the pressure actuator 8th to effect.

In a fourth step S4 becomes a force requirement F _R on the actuators 7th calculated, the classification R of the bulge 20th corresponds. In a fifth step S5 will the in S4 The calculated force requirement F _{R is} matched to an average setting F _{D of} the pressure actuator (Formula III) and Fz of the tension actuator (Formula IV) of the semi-active suspension.

In a sixth step S6 are controlled by the control device 14th Signals for adjusting the final control elements to the corresponding actuators 7a , 8a sent. This will be the pull actuator 7th according to the in step S5 by means of the formula IV determined value F _RZ in a setting that is 20% harder than the normal average setting and the pressure actuator 8th according to the in step S5 by means of the formula III determined value FRD adjusted accordingly to a setting that is 20% softer than the normal average setting. After overcoming the Bulge 20th become the actuators 7th , 8th returned to its normal position, which is intended for driving on a level surface.

In a further exemplary embodiment, the following values are measured: for the height h 15 cm, the gradient G 30% and the speed v 30 km / h. These are used in the formula (I). A classification R = 20.25 is determined for the bulge, which is above the second threshold value R ₂ but below a third threshold value R ₃ . In this case, the procedure immediately goes to step S6 forwarded, and the pull actuator 7th in the hardest setting and the pressure actuator 8th adjusted to the softest setting. After passing the road anomaly, the actuators 7th , 8th returned to their normal setting.

In a further exemplary embodiment, the following values are measured: for the height h 1 m, for the gradient G 10% and for the speed 30 km / h. These are used in the formula (I). A classification R = 300 is determined for the bulge, which is above the third threshold value R ₃ . This value is interpreted as FALSE, because there is a high probability that it is based on a malfunction of the camera. The procedure therefore becomes step S1 returned.

With an arrangement according to 1 If the procedure is carried out with the same steps, with the difference that for one actuator it is first determined whether it is under tension (then the further procedure described above for the tension actuator applies 7th is described) or is under pressure (then the further procedure described above for the pressure actuator applies 8th is described).

List of reference symbols

1

arrangement

2

Vibration damper

3

cylinder

4th

Oil storage room

5

first piston

6th

working space

7th

Pull actuator

7a

Pull actuator actuator

8th

Pressure actuator

8a

Actuator of the pressure actuator

9

Separating piston

10

Gas cushion

11

Piston rod

12

body

13

wheel

14th

Control device

15th

sensor

19th

Road surface

20th

Bulge

21st

rising edge

QUOTES INCLUDED IN THE DESCRIPTION

This list of the documents listed by the applicant was generated automatically and is included solely for the better information of the reader. The list is not part of the German patent or utility model application. The DPMA assumes no liability for any errors or omissions.

Patent literature cited

• DE 102014204519 A1 [0004]

Claims (17)

A method for controlling a semi-active suspension of at least one wheel of a vehicle, which comprises an arrangement (1) of a vibration damper (2) with at least one actuator, which by means of at least one actuator (7a, 8a) in different stages or continuously between a hardest and The softest settings can be adjusted, and wherein the vehicle has at least one sensor for detecting roadway anomalies (15) and at least one control device (14) connected to the sensor (15) and the actuator (7a, 8a), with the following steps: - Moving of the vehicle, - Detecting a lane anomaly (20) in the lane surface (19) lying ahead in the direction of movement of the vehicle, - Classifying the lane anomaly (20) in relation to the vertical dimension h, the gradient G of the edges of the lane anomaly (20) and the speed v of the vehicle, - Calculation of a force requirement F _R on the actuator, which is the classification of the lane anomaly, - matching the force requirement F _R with a current setting Fs of the actuator of the semi-active suspension, - adjusting the actuator (7, 8) depending on the classification of the road anomaly (20). Procedure according to Claim 1 , the force requirement F _{R being} matched to the properties of the vehicle. Procedure according to Claim 1 or 2 , the classification using the formula $$\text{R.}=\left({\text{n}}_{\text{2}}{\text{+ n}}_{\text{7th}}*{\text{H}}^{\text{n1}}\right)*\left({\text{n}}_{\text{3}}\text{+ G}*{\text{n}}_{\text{4th}}\right)*\left({\text{n}}_{\text{5}}\text{+ v}*{\text{n}}_{\text{6th}}\right)$$

is performed, where R is an expression for the classification and n1 - n7 are vehicle and situation-related variables. Procedure according to Claim 3 , where h must reach a threshold value hmin corresponding to a minimum height, and G lies between a minimum gradient Gmin and a maximum gradient Gmax. Procedure according to Claim 3 or 4th , the setting of the actuator (7, 8) according to $${\text{F.}}_{\text{RS}}{\text{= F}}_{\text{S.}}\text{- e.g.}*{\text{F.}}_{\text{R.}}$$

is adjusted, where z is a specific variable of the actuator (7, 8). Method according to one of the preceding claims, wherein the actuator (7, 8) is not adjusted for a classification R below a first threshold value R ₁ . Method according to one of the preceding claims, wherein the actuator is adjusted in a classification R above the first threshold value R ₁ until a second threshold value R _{2 is reached} in a harder setting relative to the average setting in a pulling action, if it is under tension, and in a softer setting relative to the average setting in a pressure action is adjusted if it is under pressure, the setting being changed in each case gradually or gradually from 0 to 100% relative to the average setting. Method according to one of the preceding claims, wherein in the case of a classification R above the second threshold value R ₂ until a third threshold value R _{3 is reached,} the actuator (7, 8) is adjusted to its hardest setting, when it is under tension, and to its softest Adjustment when under pressure. Method according to one of the preceding claims, wherein the setting of the actuator (7, 8) is not adjusted when the classification R is above the third threshold value R ₃ . Method according to one of the preceding claims, wherein the vibration damper comprises at least one tension actuator (7) and at least one pressure actuator (8). Procedure according to Claim 8 , the setting for the pressure actuator (8) according to $${\text{F.}}_{\text{RD}}{\text{= F}}_{\text{D.}}\text{- x}*{\text{F.}}_{\text{R.}}$$

is adjusted, where x is a specific variable of the pressure actuator (8). Procedure according to Claim 8 or 9 , the setting for the pull actuator (7) according to $${\text{F.}}_{\text{RZ}}{\text{= F}}_{\text{Z}}\text{- y}*{\text{F.}}_{\text{R.}}$$

is adjusted, where y is a specific variable of the tension actuator (7). Method according to one of the Claims 8 - 10 , with a classification R below a first threshold value R _1, the pressure actuator (8) and the pull actuator (7) are not adjusted. Method according to one of the Claims 8 - 13 , with a classification above the first Threshold value R ₁ until a second threshold value R _{2 is reached,} the pressure actuator can be adjusted gradually or gradually to a setting that is 0-100% softer relative to the normal average setting and the tension actuator to a setting that is 0-100% harder relative to the normal average setting . Method according to one of the Claims 8 - 14th With a classification R above the second threshold value R ₂ until a third threshold value R _{3 is reached,} the pressure actuator (8) is adjusted to its softest setting and the tension actuator (7) to its hardest setting. Method according to one of the Claims 8 - 15th , with a classification R above the third threshold value R _3, the pressure actuator (8) and the tension actuator (7) are not adjusted. Motor vehicle with a semi-active suspension of at least one wheel of a vehicle, which comprises an arrangement (1) of a vibration damper (2) with at least one actuator (7, 8), which is operated in different stages or continuously by means of at least one actuator (7a, 8a) can be adjusted between a hardest and softest setting, and which has at least one sensor for detecting roadway anomalies (15) and at least one control device (14) connected to the sensor (15) and the actuator (7a, 8a), the control device ( 14) is designed, a method according to one of Claims 1 - 14th to control.

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