Device that generates salt-state information of a road

Abstract

In order to obtain information about a salt-state of a road independently of drivers, a method that generates information about the salt-state of a road is specified that includes a determination of salt-state-dependent measurement values, processing of the measurement values into information about the salt-state of the road and outputting of the information about the salt-state of the road. A corresponding device that generates information about the salt-state of a road comprises sensors that determine of salt-state-dependent measurement values, a processing unit that is configured to process determined measurement values into information about the salt-state of the road, and output the information about the salt-state of the road.

Claims

1. A method that generates information about the salt-state of a road including: determining salt-state-dependent measurement values through road water spray; processing the measurement values into information about a salt-state of the road using hidden Markov models, Kalman filters and expectation maximization algorithms; and outputting the information.

2. The method as claimed in claim 1 further comprising associating the measurement values with salt-state values and deriving information about the salt-state of the road from the salt-state values.

3. The method as claimed in claim 1, wherein determining salt-state-dependent measurement values is through optical method, acoustic methods, electrical conductivity measurements, acceleration capability and electrical force feedback measurements.

4. The method as claimed in claim 3, wherein the optical method is Lidar.

5. The method as claimed in claim 1, wherein the road water spray produces a Schlieren image on a windscreen in determining salt-state measurement values.

6. A road salt-state information generating device, comprising: a camera configured to determine salt-state-dependent measurement values through recordation of a Schlieren image on a windscreen produced by vehicle water spray; a processor configured to translate the measurement values into salt-state information about the road; and an output device configured to display the salt-state information.

7. A method that generates information about the salt-state of a road including: determining salt-state-dependent measurement values; processing the measurement values into information about a salt-state of the road; and outputting the information, wherein the determining of salt-state-dependent measurement values is through optical method, acoustic methods, electrical conductivity measurements, acceleration capability and electrical force feedback measurements.

8. The method as claimed in claim 7, wherein the optical method is Lidar.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

(1) FIG. 1 is a flow chart of a method according to the disclosure; and

(2) FIG. 2 is a schematic representation of a device according to the disclosure.

DETAILED DESCRIPTION

(3) As required, detailed embodiments of the present disclosure are disclosed herein; however, it is to be understood that the disclosed embodiments are merely exemplary of the disclosure that may be embodied in various and alternative forms. The figures are not necessarily to scale; some features may be exaggerated or minimized to show details of particular components. Therefore, specific structural and functional details disclosed herein are not to be interpreted as limiting, but merely as a representative basis for teaching one skilled in the art to variously employ the present disclosure.

(4) According to an exemplary embodiment, information about the salt-state of a road that is being traveled along by a self-propelled automobile is generated.

(5) According to the disclosure, initially salt-state-dependent measurement values are determined, i.e. measurement values that allow conclusions to be drawn regarding the use of de-icing salt. In the present exemplary embodiment, salt-state-dependent measurement values are determined by determining the electrical conductivity of the liquid disposed on the road on the one hand, and recording the Schlieren image formed on the windscreen of the automobile by the vehicle water spray via a camera (S1 in FIG. 1) on the other hand. For the determination of the electrical conductivity, in this case an average value is formed of conductivity values measured by a plurality of sensors.

(6) In addition or alternatively, the pH value of the water on the highway or of the water spray, the sound produced by the surface of the road and any salt particles present, the scattering of light on the surface of the road and on any salt particles present, the current required for the power steering (servo current) and a recorded image of the road surface are used as measurement values.

(7) Besides the salt-state-dependent measurement values, further measurement values can be determined that are not salt-state-dependent, but for example that can be used for the subsequent processing of the measurement values. Such further measurement values can be the temperature or the air humidity for example.

(8) The electrical conductivity of the liquid on the road that is determined in the exemplary embodiment and the Schlieren image arising from the vehicle water spray itself are not direct information about the salt-state. The electrical conductivity and the Schlieren image are, therefore, processed into information about the salt-state of the road, for example by correlation with each other, with further measurement values or by comparison with previously discovered dependencies (step S2 in FIG. 1).

(9) In the simplest case, the processing can consist of direct association of information with a measurement value. Thus, for example, from a conductivity measurement value a direct conclusion can be drawn regarding the adequate or inadequate presence of de-icing salt, for example by comparing a measured conductivity value with tabulated conductivity measurement values, with which said information has already been associated.

(10) The processing of the measurement values can however also include the association of the electrical conductivity and of the Schlieren image with a defined salt-state value and the derivation of information based on the salt-state value. The association of the electrical conductivity and of the Schlieren image with a defined salt-state value can for example include the calculation of the salt concentration from the determined conductivity measurement value. The measurement values obtained can be compared with corresponding databases that enable the association of the measurement value with a salt-state value.

(11) There is also the possibility of associating both the electrical conductivity and the Schlieren image with a respective salt-state value, of forming an average value from the obtained salt-state values and then deriving information from said average value.

(12) A combination is also possible, i.e. for example for the case in which conductivity measurement values are determined via two conductivity sensors, initially average values of the measurement values of each conductivity sensor can be formed and can each be associated with a salt-state value, for example a salt concentration. An average value can also be formed from the salt-state values, from which the information about the salt-state is derived.

(13) The direct association of information with measurement values and/or the association of salt-state values with measurement values and/or the association of information with salt-state values can also be carried out based on matrices, i.e. for example a matrix is formed, in which the column indices represent different values of the conductivity and the row indices represent different temperatures. Each matrix entry then corresponds to a salt-state value or information, and is associated with a conductivity and temperature pair represented by the respective index. As a result of this, any cross effects for the case in which a measurement value or salt-state value is affected by another measurement value or salt-state value or measurement values or salt-state values influence each other, are better taken into account. In the present example, as a result the temperature dependency of the electrical conductivity can be taken into account better.

(14) In a further step of the method S3, the previous information obtained about the salt-state of the road is output, for example via a visual display or an audible signal. The output can for example be carried out to drivers of vehicles or to monitoring staff.

(15) Furthermore however, the output of the information can also be carried out to control units of a vehicle, for example an on-board electrical system control unit, which, for example, use the information as input data to derive recommendations for adjustment of the driving manner for the drivers of vehicles, or to directly control the vehicle accordingly, i.e. for example to adapt the speed of the vehicle to the salt-state.

(16) On the equipment side, there are sensors 1 that determine salt-state-dependent measurement values for carrying out the method (FIG. 2). In the present exemplary embodiment, the sensors include a conductivity sensor integrated within the running surface of a vehicle tire and a camera as an optical sensor. Via the conductivity sensor, the conductivity, for example, is determined in five individual measurements, of which the arithmetic average value is formed, which is processed in a processing unit 2 together with the recorded Schlieren image into information about the salt-state of the road via a processing unit 2. In one embodiment version, initially a defined salt concentration as a salt-state value is associated with the average value of the conductivity in the processing unit 2 on the one hand, and on the other hand the recorded Schlieren image is analyzed via a pattern recognition algorithm, which can optionally be implemented as self-learning, in order to likewise obtain the salt concentration as a salt-state value from the Schlieren image. During the association of the salt concentration with the average value of the conductivity, for example via the matrix described above, an external temperature during the conductivity measurement can be taken into account. The temperature measurement values required for this are obtained via a temperature sensor 3.

(17) From both salt concentrations, while taking into account the current temperature of the road surface, it is derived in the processing unit 2 whether the salt concentration is sufficient for the desired melting point reduction, i.e. whether the formation of ice can be prevented.

(18) The information about the salt-state of the road is output in a further step of the method via a display 4 as an output means. In addition, said information is used as an input data element for a self-propelled automobile by outputting the information to the on-board electrical system control unit, which then adapts the speed of the automobile to the salt-state of the road.

(19) While exemplary embodiments are described above, it is not intended that these embodiments describe all possible forms of the disclosure. Rather, the words used in the specification are words of description rather than limitation, and it is understood that various changes may be made without departing from the spirit and scope of the disclosure. Additionally, the features of various implementing embodiments may be combined to form further embodiments of the disclosure.