Method for estimating the height of an object using ultrasonic sensor means - Patents.com

Abstract

Method for estimating the height of an object using an ultrasonic sensor The present invention relates to a method for classifying the height of an object (3) using at least one ultrasonic sensor (2) on a vehicle (1).

Description

[Technical field]

[0001] The present invention provides a method for estimating the height of objects in the surrounding area of ​​a vehicle. Super The present invention relates to a method using an acoustic wave sensor means. [Background technology]

[0002] It is known to capture peripheral information around the vehicle using ultrasonic sensors, for example to capture the distance to other objects when parking.

[0003] The ultrasonic sensor means is an ultrasonic signal It provides spacing information based on the time of flight of the received signal, but does not directly provide height information of the detected objects since it is not possible to determine the reception angle at which the return reflection occurred.

[0004] However, it is known that the height of the object from which the reflection originates can be determined by evaluating the geometric relationship over several transmit-receive cycles. For example, if the vehicle moves between two transmit-receive cycles, the measured distance information between the ultrasonic sensor and the reflecting object, as well as the ultrasonic wave distance between the ultrasonic sensor and the reflecting object, can be used to determine the height of the object from which the reflection originates. signal By evaluating the distance information, which gives the spacing between the sensor positions of the ultrasonic sensors in the horizontal direction along the propagation direction, it is possible to calculate the height of the object. Summary of the Invention [Problem to be solved by the invention]

[0005] However, noise often leads to poor measurement results, resulting in poor height estimates with large deviations. [Means for solving the problem]

[0006] Starting from these, the object of the present invention is to provide a method for estimating the height of an object in the surrounding area of ​​a vehicle using ultrasonic sensor means, which allows a reliable estimation of the height of the reflecting object.

[0007] This object is achieved by a method having the features of the independent claim 1. Preferred embodiments are the subject of the dependent claims. A system for estimating the height of an object is the subject of parallel claim 15.

[0008] According to a first aspect, the present invention relates to a method for estimating the height of an object in the surrounding area of ​​a vehicle using ultrasonic sensor means of the vehicle, the method comprising the following steps:

[0009] First, at least two ultrasound signal is received by at least one ultrasonic sensor. ,one The ultrasonic sensors detect the movement of the vehicle. Based on Therefore, different sensors can have different sensor positions relative to the object. therefore, In other words, The received information of one ultrasonic sensor is Analyzed, The ultrasonic sensor is Vehicle movement Based on And, in terms of time continuous In the measurement cycle, Object Calculate the height of I have to Different positions relative to the object Assume Alternatively, the plurality of ultrasonic sensors may include at least two ultrasonic sensors. signal Can receive At that time These are the vehicle movements Based on and / or also Different vehicles arrangement To Based on Each object has a different sensor position relative to the object.

[0010] A first height information is then calculated, which is a measure of the squared height of the object. The height of the object is preferably a relative height of the object with respect to the installation height of the at least one ultrasonic sensor on the vehicle. In other words, the height of the object is not directly determined, but a squared height is determined to avoid erroneous estimations due to noise. The calculation of the first height information is performed based on two intervals measured between each sensor position and the object and one distance measured horizontally between the sensor positions. The first height information is determined, for example, within a first measurement cycle.

[0011] Next, the variance of the first height information is calculated.

[0012] For that purpose, at least one further ultrasonic signal is received by the at least one ultrasonic sensor. On the basis of this further ultrasonic measurement, a second height information, which is a measure of the squared height of the object, is calculated. This calculation is also performed on the basis of two distance information measured between each sensor position and the object and one distance information measured horizontally between the sensor positions. At least a part of the information required for the calculation is, for example, the second measurement The height estimation is derived from further ultrasonic measurements forming a fixed cycle, where the second measurement cycle may be the measurement cycle immediately following the first measurement cycle, but there may also be several further measurement cycles between the first and second measurement cycles. If the first and second measurement cycles do not follow one after the other immediately, for example because the vehicle has traveled a longer distance between the first and second measurement cycles, a more accurate height estimation can be achieved.

[0013] Next, the variance of the second height information is calculated.

[0014] In a further step, by combining the first and second height information 、 average was made Height Information is calculated , and, the average of the first and second height information was made By combining the dispersion 、 Average height information was made The variance is calculated. Classification of detected objects into a single height class kind is performed by calculation of at least one probability value based on a normal distribution function having the averaged height information as the mean value and the averaged variance of the height information as the variance.

[0015] A technical advantage of the method according to the invention is that a reliable determination of the height of a reflecting object can be achieved by determining the height information taking into account the squared height of the object, thus obtaining, by repeated use, a distribution of height information values ​​that corresponds better to a normal distribution than a direct determination of the unsquared height of the object.

[0016] According to an embodiment, a number of further height information (i.e. further height information other than the first and second height information) which are measures of the squared height of the object are recursively calculated, as well as a variance of this further height information. was made The height information is calculated by combining the height information, preferably all the recursively determined height information, and averaging the height information. was made The variance is determined by combining the variance of the height information, preferably all the recursively determined variances. The recursive determination of a large number of height information and their variances, and the combination of the height information, allows a reliable determination of the height of the object. kind can be achieved.

[0017] According to one embodiment, the first, second and / or also Further height information is given by the following formula: 、

number

[0018] The above formula does not contain a root term as would be the case for directly determining the height difference h, so negative values ​​of H or the squared height h, which can occur due to noise, will not cause invalid results.

[0019] According to one embodiment, the first, second and / or also The variance of the further height information is determined based on a first order analysis of variance method, whereby the variance of the height information is preferably calculated by adding together a number of addends, which take into account the change in the height information in response to changes in the input variables used to calculate the height information.

[0020] According to one embodiment, the first, second and / or also The variance of the further height information is calculated using the following formula: 、

number

[0021] According to one embodiment, the average was made The height information is calculated using the following formula: 、

number

[0022] The estimated height information for each measurement cycle can be height information obtained from individual measurements, but it can also be already averaged height information, i.e. it is itself an average of several measurements. This is true in the first and / or second measurement cycles. also The same applies to the variance of the height information in the second measurement cycle.

[0023] According to one embodiment, the average of the height information was made The variance is calculated using the following formula: 、

number

[0024] According to certain other embodiments, the average was made Height information and average height information was made The calculation of the variance is carried out based on the least mean squares method, with the aid of weighting factors chosen to take into account the correlations between the measurements (weighted least squares method).

[0025] According to one embodiment, the probability value for assigning a height class to an object is calculated using the following formula: 、

number

number

number

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[0026] The object is at the lower limit or The probability of being within the height range defined by the upper limit is calculated by multiplying it by the average was made The height information is the median, and the average was made This can be determined by considering it as a normal distribution of the height information with a variance equal to the variance.

[0027] According to one embodiment, the calculation of the height class is performed based on a correction function that takes into account the deviation of the statistical distribution of the height information from a normal distribution function, thereby minimizing errors due to the deviation of the statistical distribution of the height information from a normal distribution function.

[0028] According to one embodiment, the correction function is estimated based on a data series of different interval information between each sensor position and the object, and height information calculated based on different horizontally measured distance information. or It is then analyzed what influence the distance information has on the statistical distribution of the height information, and depending on this a correction function is selected.

[0029] According to one embodiment, the lower limit and / or alsoThe upper limit is adjusted based on a correction function, so that the deviation of the statistical distribution of the height information when determining the height of the object from the normal distribution function is adjusted based on the lower limit and / or also can be compensated for by adapting the upper limit.

[0030] According to one embodiment, the distance information is determined based on odometry data of the vehicle. In other words, the odometry system of the vehicle can provide information indicating how the vehicle has moved between two measurement cycles of at least one ultrasonic sensor. However, this vehicle movement does not necessarily correspond to the direction of transmission of the ultrasonic sensor. or Since the distance information is not implemented in the receiving direction, i.e. in the transmitting direction of the ultrasonic sensor, or The spacing of the sensor positions in the receiving direction must be calculated from the vehicle's odometry data.

[0031] According to one embodiment, the object is assumed to be a vertical linear object, and the transmission and reception direction of the at least one ultrasonic sensor, as well as the direction in which distance information is measured, are assumed to be perpendicular to the vertical direction of the linear object.

[0032] According to an alternative embodiment, the object is modelled using an object contour line based on information determined by the ultrasonic sensor means over multiple detection cycles, and the distance information is assumed to be the difference between this line and the horizontally measured distance of the sensor position.

[0033] According to a further aspect, the present invention relates to a vehicle-mounted ultrasonic sensor means and a computing unit. Preparation The present invention also relates to a system for estimating the height of a moving object. It is The system comprises the following steps: 、 a) receiving at least two ultrasonic signals by at least one ultrasonic sensor of the ultrasonic sensor means; And , one1 Ultrasonic Sensor but , vehicle movement Based on have different sensor positions relative to the object, also teeth 、 Multiple Number of ultrasonic sensors but , vehicle movement I'm not going to Beauty / Or car Based on the different arrangements in both I , have different sensor positions relative to the object 、 Step, b )each The sensor positions and the distance between the objects are measured. and Based on the horizontally measured distance information between the sensor positions, First height information, which is a measure of the squared height of the object, calculating by a computing unit; 、 c) calculating by the arithmetic unit a variance of the first height information; 、 d ) small At least one ultrasonic sensor At least one further ultrasound signal Receive, and ,each The sensor positions and the distance between the objects are measured. and Based on the horizontally measured distance information between the sensor positions, A second height information, which is a measure of the squared height of the object. Calculation steps 、 e) calculating the variance of the second height information 、 f) combining and averaging the first and second height information was made Calculate height information, combine the variances of the first and second height information, and average the height information. was made Calculating the variance 、 g) Averaged height information as the mean value and , a normal distribution function with the averaged variance of the height information as the variance To base Based on this, At least one probability value is calculated by the arithmetic unit to classify the detected objects into one height class. kindSteps to take 、 It is configured to run .

[0034] In the present invention, "approximately" and "substantially" mean also Expressions such as "approximately" and "approximately" indicate an error of + / - 10%, preferably + / - 5%, from the exact value, and also is interpreted as an error with no significance to the function.

[0035] Further developments, advantages and scope of application of the invention are shown in the following description with reference to exemplary embodiments and drawings, in which all described and / or / without departing from the spirit and scope of the invention. also The illustrated features may be used individually and in any combination as claimed in the claims. also is the subject of the present invention independently of any combination with the reference thereto. The contents of the claims are also incorporated into the specification.

[0036] The present invention will now be described in detail with reference to the drawings and examples. 。 [Brief description of the drawings]

[0037] [Figure 1] FIG. 1 illustrates diagrammatically a vehicle equipped with ultrasonic sensors including ultrasonic sensors distributed around the vehicle and a computing unit for evaluating the information provided by the ultrasonic sensors; [Diagram 2] Figure 2 illustrates a schematic of the capture of surrounding objects by one ultrasonic sensor at two different sensor positions; [Diagram 3] FIG. 3 illustrates a histogram showing the statistical distribution of height information H; and [Figure 4] FIG. 4 illustrates a flow chart highlighting the steps of a method for determining the height of an object. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0038] 1 illustrates very diagrammatically a vehicle 1. The vehicle 1 is equipped with a number of ultrasonic sensors 2 with which perimeter acquisition is performed.

[0039] The ultrasonic sensor 2 is connected to at least one computing unit 4 with which a method for estimating the height of an object 3 in the vicinity of the vehicle 1 is implemented, as described below.

[0040] FIG. 2 illustrates an example of a capture situation in which one ultrasonic sensor 2 of a vehicle 1 is used to capture an object 3 that is lower than the mounting height of the ultrasonic sensor 2 on the vehicle 1.

[0041] The height determination of the object 3 can for example be performed by multiple measurements with one ultrasonic sensor 2, where for example a first measurement is performed at a first sensor position P1 and a second measurement is performed at a second sensor position P2, which sensor positions P1 and P2 are different because the vehicle 1 is moving. Alternatively, the height determination of the object 3 can also be performed by at least two measurements with two different ultrasonic sensors 2 of the vehicle 1, which are arranged at different positions of the vehicle 1 and therefore have different distances to the object 3.

[0042] 2, first distance information r1 is determined by the ultrasonic sensor 2 at a first sensor position P1. The first distance information r1 corresponds to the distance between the ultrasonic sensor 2 at the position P1 and the object 3, measured in a straight line of sight. Similarly, second distance information r2 is determined by the ultrasonic sensor 2 at a second sensor position P2. The second distance information r2 corresponds to the distance between the ultrasonic sensor 2 at the position P2 and the object 3, measured in a straight line of sight.

[0043] The distance between the first and second sensor positions p1, p2 measured horizontally on the line connecting the sensor 2 and the object 3 is hereinafter referred to as distance information s. The height difference measured vertically between the object 3 and the ultrasonic sensor 2 is hereinafter referred to as height h.

[0044] From the geometrical relationship, the height h is as follows: formula,

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[0045] The problem is that noise can cause terms in the root to become negative, making it impossible to calculate the height.

[0046] Below is a way to divide the height of object 3, which avoids the problem of the terms in the root having negative values. kind This application discloses a method for doing so.

[0047] In the method according to the invention, instead of the height h, height information H, which corresponds to the square of the height h, is estimated.

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[0048] Since individual measurements may contain significant errors and therefore may lead to incorrect height estimates, multiple measurements are taken and the height of object 3 is estimated based on averaging the estimated height information H and estimating the variance of the height information H. or , its height kind will be implemented.

[0049] To determine the variance of the height information H, for example a first order variational analysis is performed.

[0050] This can be achieved, for example, by the formula 、

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[0051] The first derivative of the height information H with respect to r1 is calculated as follows:

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[0052] The first derivative of the height information H with respect to r2 is calculated as follows:

number

[0053] The first derivative of the height information H with respect to s is calculated as follows:

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[0054] It should be noted that it is advantageous to combine multiple measurements performed by ultrasonic sensor means of the vehicle 1, for example in object tracking during vehicle movement. The variance of each of the height information H can be used as a weighting factor.

[0055] In the case where the first height information H' and the second height information H'' are also calculated, the average was made The height information is given by the following formula: 、

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[0056] average was made The variance is formula,

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[0057] It is important to note that the height information H', H'', or The variances Var[H'] and Var[H''] can refer not only to one measurement cycle (i.e., the individual height information H obtained by distance measurements at two different sensor positions using one sensor) but also to several measurement cycles, i.e., the height information H', H'', or, the variances Var[H'] and Var[H''] themselves can be mean values.

[0058] Alternatively, the combination of measurements to obtain the height information H can be based on the weighted least squares method, where the weighting factors are chosen to take into account the correlation between both measurements.

[0059] After determining the plurality of height information H, the height h of the object 3 can be determined based on the plurality of height information H. kind It is particularly preferred that the

[0060] The height kind can for example be implemented to verify with what probability an object 3 has a height h that is within a certain height range.

[0061] In the case where a height class is defined by a lower limit a and an upper limit b, the probability that the height of object 3 falls into that height class is calculated using the following formula: 、

number

number

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[0062] Height class is the lower limit or Not limited by an upper limit, i.e., the lowest, or , the highest height class, the lower limit a may have the value -∞ and the upper limit b may have the value +∞.

[0063] Of course, the thresholds a and b in Equation 9 are also H=h 2 must be squared based on the relationship, i.e., 0.3 m kind The threshold is 0.09m. 2 must be converted to

[0064] In Equation 9, the average was made We assume that the height information is uniformly distributed in x. In reality, however, the average was made Height information often deviates from a normal distribution.

[0065] Figure 3 shows the actual distribution of height information H by means of a histogram, where the actual height h of the object relative to the sensor was 0.1 m. As can be seen, the height information H is not normally distributed, since the distribution is not linearly symmetric about the vertical axis.

[0066] To compensate for this deviation, at least one of the thresholds a, b can be adjusted using a correction function. Particularly preferably, a correction function can be selected which adjusts at least one of the thresholds in dependence on the distance information r1, r2 as well as on the distance information s. Such correction functions can be used, for example, in simulations, based on which the dependence of the height information H on the interval information r1, r2 and the distance information s is calculated. or , can be determined by actual data.

[0067] As mentioned above, distance information s, i.e. the change in sensor position P1, P2 along the transmission and reception direction of the ultrasonic sensor, is required.

[0068] The vehicle movement itself can be determined from the information of the vehicle's odometry unit. The direction of the vehicle's movement does not necessarily have to be the same as the direction of transmission and reception of the ultrasonic signal between the ultrasonic sensor and the object.

[0069] The distance information s can be estimated, for example, as follows:

[0070] The object 3 can be regarded, for example, as a linear object. The linear object is then considered to be arranged relative to the transmission and reception direction of the ultrasonic sensor 2 such that the transmission and reception direction of the ultrasonic sensor 2 is perpendicular to the linear object. The distance information s is thereby assumed to be measured perpendicular to the longitudinal axis of the linear object. If the direction of movement of the vehicle 1 and its absolute movement are known, the distance information s can be calculated on this basis.

[0071] Alternatively, multiple measurements and tracking can be used to find the object contour, such as a curve, or , lines of any shape, also is a polygon, or , it is also possible to determine the polygon segment. In such a case, the distance information s can be calculated directly, i.e., as the difference between the line describing the object contour from each of the sensor positions P1, P2.

[0072] FIG. 4 shows, in its schematic representation, the steps of the method according to the invention for estimating the height of an object using ultrasonic sensor means of a vehicle.

[0073] First, at least two ultrasound signalare received by at least one ultrasonic sensor 2, which may have different sensor positions relative to the object depending on the motion of the vehicle. Alternatively, multiple ultrasonic sensors 2 may be connected to each other based on the motion of the vehicle and / or also The sensors may have different positions relative to the object 3 based on different placement on the vehicle 1 (S10).

[0074] A first height measurement H, which is a measure of the squared height h of the object, is then calculated based on two interval measurements r1, r2 measured between each sensor position and the object 3, and one distance measurement s measured horizontally between the sensor positions (S11).

[0075] Based on this, the variance of the first height information is calculated (S12). Next, at least Also 1 Further The ultrasonic signals are received by at least one ultrasonic sensor, and second height information, which is a measure of the squared height of the object, is calculated based on the two interval information measured between each sensor position and the object, and the horizontally measured distance information between the sensor positions (S13).

[0076] Based on this, the variance of the second height information is calculated (S14).

[0077] Next, average height information obtained by combining the first and second height information, and the average of the first and second height information was made Average of height information obtained by combining variances was made The variance is calculated (S15).

[0078] Finally, the classification of detected objects into a single height class is performed. kindis performed by calculation of at least one probability value based on a normal distribution function having the averaged height information as the mean value and the averaged variance of the height information as the variance (S16).

[0079] The invention has been described by way of the above examples, however it will be appreciated that numerous modifications and variations are possible without departing from the scope of the invention as defined in the appended claims. This application relates to the invention described in the claims, but also includes the following as other aspects. 1. car Both(1) Super Method for estimating the height of an object (3) using ultrasonic sensor means And, The following steps: a) receiving at least two ultrasonic signals by at least one ultrasonic sensor (2) (S10); And , one (2) Ultrasonic Sensors but , Vehicle movement Based on and have different sensor positions relative to the object (3), also teeth, Multiple Ultrasonic Sensors (2) but , vehicle movement I'm not going to Beauty / or car Based on the different arrangements in both (1) I , have different sensor positions (P1, P2) relative to the object (3). 、 Step (S10), b )each Two distances (r1, r2) measured between the sensor positions (P1, P2) and the object (3) and Based on the horizontally measured distance information(s) between the sensor positions, The first height information (H) is a measure of the squared height (h) of the object. Calculating step (S11) 、 c) calculating the variance of the first height information (S12) 、 d) by at least one ultrasonic sensor (2) at least One more Ultrasonic Signal Received Believe and ,each Two distances (r2,r3) measured between the sensor positions (P2,P3) and the object (3) and Based on the horizontally measured distance information(s) between the sensor positions, A second height measurement, which is a measure of the squared height (h) of the object. Calculate 、 Step (S13); e) calculating the variance of the second height information (S14) 、 f) combining and averaging the first and second height information was made Calculate height information, combine the variances of the first and second height information, and average the height information. was made Calculate the variance 、 Step (S15) 、 g) Averaged height information as the mean value and , a normal distribution function with the averaged variance of the height information as the variance To base Based on this, By calculating at least one probability value (p), the detected object (3) is classified into one height class. To minutes kind Step (S16) 、 Equipped with A method characterized in that . 2. Recursively, a number of further height information (H) which is a measure of the squared height (h) of the object, as well as the variance of this further height information, are calculated and averaged. was made By combining the height information, and averaging the height information, was made 2. The method of claim 1, wherein the variance is determined by combining the variances of the height information. 3. First, second, and / or also Further height information (H) is given by the following formula: 、

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[0080] 1 vehicle 2. Ultrasonic Sensor 3. Objects h Height H Height information p probability value P1 First sensor position P2 Second sensor position r1 First interval information r2 Second interval information s Distance information

Claims

1. A method for estimating a height of an object (3) using ultrasonic sensor means of a vehicle (1), comprising: The following steps: a) receiving at least two ultrasonic signals by at least one ultrasonic sensor (2) (S10), A single ultrasonic sensor (2) has different sensor positions relative to the object (3) based on the movement of the vehicle, or The ultrasonic sensors (2) have different sensor positions (P1, P2) relative to the object (3) based on the vehicle's motion and / or different placement on the vehicle (1). Step (S10), b) calculating (S11) a first height information (H) which is a measure of the squared height (h) of the object based on two interval information (r1, r2) measured between each sensor position (P1, P2) and the object (3) and horizontally measured distance information (s) between the sensor positions; c) calculating the variance of the first height information (S12); d) receiving at least one further ultrasonic signal by at least one ultrasonic sensor (2) and calculating (S13) a second height information, which is a measure of the squared height (h) of the object, based on two interval information (r2, r3) measured between each sensor position (P2, P3) and the object (3) and on horizontally measured distance information (s) between the sensor positions; e) calculating the variance of the second height information (S14); f) calculating averaged height information by combining the first and second height information, and calculating an averaged variance of the height information by combining the variances of the first and second height information (S15); g) classifying the detected objects (3) into one height class (S16) by calculating at least one probability value (p) based on a normal distribution function having the averaged height information as the mean value and having the averaged variance of the height information as the variance; Equipped with A method comprising:

2. Recursively, a number of further height information (H) are calculated, which are measures of the squared height (h) of the object, and a variance of this further height information; and an averaged height information is determined by combining the height information, and an averaged variance of the height information is determined by combining the variances of the height information; 2. The method of claim 1 .

3. The first, second and / or further height information (H) is determined according to the following formula: [0010] It is calculated by In this formula, h is the height difference between the at least one ultrasonic sensor and the object; r1 is the spacing between the first transmitter position and the object in the transmission / reception direction; r2 is the spacing between the second transmitter position and the object in the transmit / receive direction; s is distance information measured horizontally as the separation between the first and second transmitter positions; Each sensor position (P1, P2) is at the same height.

3. The method according to claim 1 or 2.

4. 3. The method according to claim 1 or 2, characterized in that the variance of the first, second and / or further height information is determined based on a first order variance analysis method.

5. The calculation of the variance of the first, second and / or further height information (H) is carried out according to the following formula: [0025] It is carried out by In this formula, r1 is the spacing between the first transmitter position and the object in the transmission / reception direction; r2 is the spacing between the second transmitter position and the object in the transmit / receive direction; s is distance information measured horizontally as the separation between the first and second transmitter positions; dH / dr １ is r １ is the first derivative of the height information H relating to dH / dr ２ is r ２ is the first derivative of the height information H relating to dH / ds is the first derivative of the height information H with respect to s, Var[r １ ] is the variance of the spacing between the first transmitter position and objects in the transmission / reception direction, Var[r ２ ] is the variance of the spacing between the second transmitter position and objects in the transmission / reception direction, Var[s] is the variance of the distance information measured horizontally as a distance between the first and second transmitter positions; 3. The method according to claim 1 or 2.

6. The averaged height information is calculated using the following formula: [0030] It is carried out by In this formula, H′ is the height information estimated from the first measurement cycle; H″ is the height information estimated from the second measurement cycle; Var[H'] is the variance of the height information in the first measurement cycle; Var[H″] is the variance of the height information in the second measurement cycle; 3. The method according to claim 1 or 2.

7. The averaged variance of the height information is calculated using the following formula: [0045] It is carried out by In this formula, Var[H'] is the variance of the height information in the first measurement cycle; Var[H″] is the variance of the height information in the second measurement cycle.

3. The method according to claim 1 or 2.

8. 3. The method according to claim 1 or 2, characterized in that the calculation of the averaged height information and the averaged variance of the height information is performed based on the least mean square method.

9. The probability value (p) for assigning a height class to an object is calculated using the following formula: [0050] It is carried out by In this formula, [006] is normally distributed, a is the lower limit of membership in each height class, b is the upper limit of membership to each height class, [0070] is the averaged height information, [0080] is the averaged variance, 3. The method according to claim 1 or 2.

10. 3. The method according to claim 1 or 2, characterized in that the calculation of the height class is performed on the basis of a correction function which takes into account the deviation of the statistical distribution of the height information (H) from a normal distribution function.

11. 11. The method according to claim 10, characterized in that the correction function is estimated based on a data series of different interval information (s) between each sensor position (P1, P2) and the object (3) and height information (H) calculated based on different horizontally measured distance information.

12. 11. The method of claim 10, wherein the lower and / or upper limits used in calculating the probability value (p) are adjusted based on a correction function.

13. 3. The method according to claim 1 or 2, characterized in that the object (3) is assumed to be a longitudinal linear object and the transmission and reception direction of the at least one ultrasonic sensor (2), as well as the direction in which the distance information (s) is measured, is assumed to be perpendicular to the longitudinal direction of the linear object.

14. 3. A method according to claim 1 or 2, characterized in that the object (3) is modelled with an object contour line based on information determined by ultrasonic sensor means in several detection cycles, and the distance information (s) is assumed to be the difference between this line and the horizontally measured distance of the sensor positions (P1, P2).

15. A system for estimating the height of an object (3) comprising ultrasonic sensor means and a computing unit (4) mounted on a vehicle (1), comprising: The following steps: a) receiving at least two ultrasonic signals by at least one ultrasonic sensor (2) of an ultrasonic sensor means, A single ultrasonic sensor (2) has different sensor positions (P1, P2) relative to the object (3) based on the vehicle's motion, or The ultrasonic sensors (2) have different sensor positions (P1, P2) relative to the object (3) based on the vehicle's motion and / or different placement on the vehicle (1); Step, b) calculating, by a calculation unit (4), a first height information (H) which is a measure of the squared height (h) of the object based on two interval information measured between each of the sensor positions (P1, P2) and the object (3) and on the horizontal distance information (s) between the sensor positions (P1, P2); c) calculating the variance of the first height information (H) by a calculation unit (4); d) receiving at least one further ultrasonic signal by at least one ultrasonic sensor (2) and calculating a second height information, which is a measure of the squared height (h) of the object, based on two interval information (r2, r3) measured between each sensor position (P2, P3) and the object (3) and on horizontally measured distance information (s) between the sensor positions; e) calculating the variance of the second height information; f) combining the first and second height information to calculate averaged height information and combining the variances of the first and second height information to calculate an averaged variance of the height information; g) classifying the detected object (3) into one height class by calculating, by a calculation unit (4), at least one probability value (p) based on a normal distribution function having the averaged height information as the mean value and having the averaged variance of the height information as the variance; It is configured to run A system characterized by:

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