Method and device for automatically or semi-automatically adjusting a chassis

Abstract

Method for automatically or semi-automatically adjusting the chassis of a vehicle (10) having the following features: - the vehicle (10) assesses road conditions using vehicle sensors, which include a camera to capture an image of the road conditions, - Assessing road conditions includes digital image processing, which includes the detection of lane boundaries, - the vehicle (10) determines a current position of the vehicle (10), - the vehicle (10) transmits the road conditions and position to a central server, - another vehicle (10) queries the road condition from the server and - the other vehicle (10) recommends a suspension setting depending on the road conditions queried, characterized by the following features: - the vehicle (10) indicates a crest to the server if the road boundaries beyond a specified distance from the vehicle (10) are not detected, - the transmission of the road condition by the vehicle (10) causes the server to store information about a curb, and - the server assigns the information to the position, stores the position and the road condition and makes the information available to the next vehicle (10) when the next vehicle (10) approaches the position.

Description

[0001] The present invention relates to a method according to the preamble of claim 1. The invention further relates to a device provided for carrying out such a method.

[0002] Acceleration sensors have been widely used in vehicle manufacturing for many years, for example, for airbag deployment or as part of the Electronic Stability Program (ESP). The measuring principle of an acceleration sensor is based on the well-known relationship between acceleration and force. A mass subjected to a certain acceleration reacts with an inertial force on the body that imposes the acceleration on the mass. By measuring the force acting between the mass and the body, the acceleration can be determined according to this relationship. By combining three acceleration sensors offset from each other by 90°, each responding only to forces in one spatial direction, accelerations in each of these directions can therefore be measured.

[0003] In addition to standard accelerometers, the state of the art includes further devices for capturing physical road surface characteristics, such as a driver assistance camera behind the windshield that can be used for various driver assistance functions. The lane markings optically detected in this way allow conclusions to be drawn about the road's course and thus represent an important input parameter for functions such as the lane departure warning system (LDW) or even active lane keeping support (LKS).

[0004] In some cases, it has also been suggested to collect relevant vehicle data and make it available via a server. For example, DE 10 2007 042 877 A1 discloses a motor vehicle with a detection device for recording a physical road surface property of the roadway traveled by the motor vehicle, with a position determination device for determining the position of the motor vehicle, with a transmission device for sending road surface property position data objects, and with a computer device configured such that a recorded road surface property and the corresponding position are converted into a road surface property position data object, and that the road surface property position data object is sent by the transmission device.

[0005] DE 10 2013 016 974 A1, DE 103 44 053 A1, DE 11 2009 005 342 T5 and DE 41 24 654 A1 each disclose the subject matter of the preamble of claim 1.

[0006] However, the state of the art does not include a comprehensive procedure that assists the driver in selecting the optimal chassis setting by utilizing such "swarm data".

[0007] The present invention was made in light of the prior art described above, the object of which was to provide an automatic or semi-automatic method for chassis adjustment and a corresponding device.

[0008] This problem is solved by a method having the features of claim 1 and a device having the features of claim 7.

[0009] One advantage of this solution lies in the possibility of deriving the most favorable settings for suspension stiffness and height for the expected road surface, taking into account any road damage, crests, or dips. This includes all adjustment parameters of spring, damper, and stabilizer systems, as well as the vehicle's position relative to the road surface, such as height, roll and pitch angles, and available clearance in parking garages, bridges, tunnels, etc.

[0010] Furthermore, this helps to avoid damage to the underbody and roof caused by adjusting the height of the vehicle body, for example in connection with curbs, rough roads, off-road, parking garages, ramps, clearance height, etc.

[0011] The definition of semi-automatic in this context includes the suggestion of an improved chassis control system setting to the driver and the acceptance of this setting by the driver either through confirmation or selection of this setting by the driver in the vehicle's operating system. Automatic defines the automatic acceptance of the suggested setting without driver confirmation.

[0012] Further advantageous embodiments of the invention are specified in the dependent claims.

[0013] An embodiment of the invention is shown in the drawings and is described in more detail below. Fig. Figure 1 shows a vehicle equipped with a device according to the invention in an object-related right-handed coordinate system. Fig. Figure 2 shows the East-North-Up reference system commonly used as a reference coordinate system for land vehicles.

[0014] Fig. Figure 1 illustrates a land vehicle 10 equipped according to the invention in a body-fixed coordinate system, which in the basic orientation of the vehicle 10 is aligned with the in Fig. The reference coordinate system shown in section 2 is used to describe the orientation of vehicle 10 within the object coordinate system. Fig. 1. The roll, pitch, and yaw angles ϕ, θ, ψ, known from aviation, are used here, which are transformed into the coordinate axes x, y, z by means of transformations familiar to those skilled in the art. Fig. 1 and Fig. can be converted to 2 defined Cartesian coordinates.

[0015] In particular, to determine the roll, pitch, and yaw angles ϕ, θ, ψ of the Fig. To detect the road conditions, vehicle 10 is equipped with a sensor system comprising three acceleration sensors (not shown in the drawing), which allows vehicle 10 to reliably assess the road conditions. The sensor system of vehicle 10 also includes a camera and / or at least one suspension travel sensor connected to the chassis of vehicle 10 and / or at least one wheel acceleration sensor and / or at least one wheel pressure sensor.

[0016] The described sensor system provides the vehicle 10 with a variety of indications of possible crests, dips, unpaved roads or road damage such as potholes that occur in the vehicle 10's roadway and make a fine adjustment of the chassis desirable.

[0017] For example, the image delivered by the camera and digitally processed allows for the early detection of potential crests. In this respect, experts in optical pattern recognition are familiar with relevant algorithms that allow the course of the lane markings to be traced based on the supplied image data. If it turns out that the camera, mounted behind the windshield of vehicle 10, for example, only detects the lane markings up to a short distance, this horizon allows the conclusion to be drawn about an approaching crest in the road.

[0018] Similarly, the acceleration sensors also provide a wide range of odometric information about the road surface. Based on the in Fig. The pitch angle θ shown in Figure 1 provides information on the signed road gradient, indicating whether a crest is being crossed when transitioning from a positive to a negative gradient, and whether a dip is present in the reverse case.

[0019] The appearance of depressions or crests is also indicated by a sudden change in the acceleration in the vertical direction z, which is also recorded, according to Fig. 1 and Fig. 2. If a decrease in vertical acceleration is observed, a crest in the road surface should be assumed; if an increase, a dip in the road surface. Significant fluctuations in this measurement, however, indicate possible unevenness in the form of potholes or an unpaved road surface.

[0020] Finally, vehicle 10 also incorporates the data supplied by the suspension travel sensor into its assessment of the road conditions. Here, too, short-term fluctuations are to be interpreted as an indication of vibrations, such as those caused by unpaved roads or potholes. A sudden increase in suspension travel, however, may serve vehicle 10 as an indication of a possible crest, while the opposite development may indicate a corresponding dip in the road.

[0021] The raw data continuously collected in this way, or the derived evaluation, is transmitted by vehicle 10, along with current position data supplied, for example, by a standard GPS receiver, to a central server. This server stores the received data pairs or assigns the additional information about the corresponding road conditions to an existing position data record. Within this framework, the server can perform plausibility checks or consolidate the data from different sources in order to exclude erroneous data or malfunctions in the sensors of individual vehicles 10 from its data pool, thereby increasing the quality of the data through continuous adjustment and improvement of the underlying statistics.

[0022] If, given the amount of data collected, the server's road condition information for a particular position can be considered sufficiently reliable, the server then transmits the available data to other vehicles 10 approaching that position. These other vehicles 10 can use the available data to derive suitable recommendations for their respective suspension settings. If the optimal setting does not already correspond to the current values, the other vehicles 10 provide their respective drivers with corresponding recommendations regarding suspension stiffness and height. This includes all setting parameters of spring, damper, and stabilizer systems, as well as the vehicle's position relative to the road surface, such as height, roll and pitch angles, or available clearance in parking garages, bridges, tunnels, etc.If the driver confirms this, the suggested settings can be applied immediately.

Claims

[1] Method for automatically or semi-automatically adjusting the chassis of a vehicle (10) having the following features: - the vehicle (10) assesses road conditions using vehicle sensors, which include a camera to capture an image of the road conditions, - Assessing road conditions includes digital image processing, which includes the detection of lane boundaries, - the vehicle (10) determines a current position of the vehicle (10), - the vehicle (10) transmits the road conditions and position to a central server, - another vehicle (10) queries the road condition from the server and - the other vehicle (10) recommends a suspension setting depending on the road conditions queried, characterized by the following characteristics: - the vehicle (10) indicates a crest to the server if the road boundaries beyond a specified distance from the vehicle (10) are not detected, - the transmission of the road condition by the vehicle (10) causes the server to store information about a curb, and - the server assigns the information to the position, stores the position and the road condition and makes the information available to the next vehicle (10) when the next vehicle (10) approaches the position. [2] Method according to claim 1, characterized by the following characteristics: - The sensor system includes an acceleration sensor to detect road inclination and - the vehicle (10) indicates a crest or a dip to the server when the acceleration sensor detects a change in the sign of the road gradient. [3] Method according to claim 2, characterized by the following characteristics: - the accelerometer also detects vertical acceleration, - the vehicle (10) alerts the server to a crest when the acceleration sensor detects a sudden decrease in vertical acceleration, - the vehicle (10) alerts the server to a dip when the acceleration sensor detects a sudden increase in vertical acceleration and - the vehicle (10) alerts the server to a pothole or an unpaved road when the acceleration sensor detects a strong fluctuation in vertical acceleration. [4] Method according to any one of claims 1 to 3, characterized by the following characteristics: - the sensor system includes a suspension travel sensor connected to the chassis for detecting the suspension travel of the vehicle (10), - the vehicle (10) alerts the server to a crest when the suspension travel sensor detects a sudden increase in suspension travel, - the vehicle (10) alerts the server to a dip when the suspension travel sensor detects a sudden decrease in suspension travel and - the vehicle (10) alerts the server to a pothole or unpaved road when the suspension travel sensor detects a large fluctuation in suspension travel. [5] Method according to any one of claims 1 to 4, characterized by the following characteristics: - the sensor system includes at least one wheel acceleration sensor connected to the chassis for detecting the wheel acceleration of one wheel of the vehicle (10). [6] Method according to any one of claims 1 to 5, characterized by the following characteristics: - the sensor system includes at least one wheel speed sensor connected to the chassis for detecting the wheel speed of one wheel of the vehicle (10). [7] Device for a vehicle (10) for carrying out a method according to any one of claims 1 to 4, characterized by the following characteristics: - sensors for assessing road conditions, - a transmission device for transmitting the road condition to a central server and - an adjustable suspension.

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