阅读说明：本技术 用于确定停车位的占用状态的方法 (Method for determining the occupancy state of a parking space ) 是由 P·鲍库茨 于 2019-10-07 设计创作，主要内容包括：本发明涉及一种用于确定停车空间的停车位的占用状态的方法。此外,本发明涉及一种具有至少一个雷达传感器(20)和处理单元(30)的装置(10),其中,所述处理单元(20)设置为用于实施根据本发明的方法。此外,本发明也涉及一种具有至少一个停车位的停车空间,其中,所述停车位具有根据本发明的装置(10)。(The invention relates to a method for determining the occupancy state of a parking space. The invention further relates to an apparatus (10) having at least one radar sensor (20) and a processing unit (30), wherein the processing unit (20) is provided for carrying out the method according to the invention. The invention also relates to a parking space having at least one parking space, wherein the parking space has a device (10) according to the invention.)

1. Method for determining an occupancy state of a parking space, the method comprising at least the following method steps:

a. sensing radar measured values (22) of a plurality of radar channels by means of at least one radar sensor (20) at different times within a predetermined time duration, wherein each radar measured value (22) is composed of a real part and an imaginary part,

b. the radar measured values (22) at the respective time are transformed into a polar coordinate system,

c. determining a first parameter and a second parameter of each of the transformed radar measurements (23) by means of a linear least squares polynomial fitting method,

d. and determining the occupation state of the parking space according to the first parameter.

2. Method according to claim 1, characterized in that the occupancy state is determined in method step d by comparing the first parameter with a threshold value, wherein the parking space is determined as occupied when the first parameter is greater than the threshold value.

3. The method of any preceding claim, wherein the threshold is 1.

4. Method according to one of the preceding claims, characterized in that method step e and method step f are additionally carried out, wherein in method step e the variance of the first parameter and the second parameter determined in method step c of the transformed radar measurement (23) of the radar measurement (22) sensed at one of the time instants is determined, wherein in method step f the validity of the radar measurement (22) sensed at that time instant is determined from the variance.

5. Method according to claim 4, characterized in that in the method step f, the validity of the radar measured value (22) sensed at that time is determined by comparing the variance with a further threshold value, wherein the validity of the radar measured value (22) is considered sufficient when the variance is smaller than the further threshold value.

6. The method of claim 5, wherein the additional threshold is 10.

7. An arrangement (10) with at least one radar sensor (20) and a processing unit (30), characterized in that the processing unit (30) is arranged for carrying out the method according to any one of the preceding claims.

8. Parking space with at least one parking space, wherein the parking space has a device (10) according to claim 7.

Technical Field

The invention relates to a method for determining the occupancy state of a parking space.

Typically, the occupancy state of the parking space can be ascertained and monitored by means of a plurality of different sensors. Sensors suitable for this are, for example, radar sensors, in which case the occupancy state is inferred on the basis of the sensed radar measured values. A general problem here is how the occupancy state of the parking space can be inferred from the sensed radar measurements.

The invention further relates to a device which is provided for carrying out the method according to the invention.

The invention also relates to a parking space having at least one parking space, wherein the parking space has a device according to the invention.

Disclosure of Invention

The invention relates to a method for determining the validity of radar measurements for determining the occupancy state of a parking space, comprising at least the following method steps:

a. sensing radar measurements of a plurality of radar channels at a plurality of different times in each case for a predetermined duration by means of at least one radar sensor, wherein each radar measurement consists of a real part and an imaginary part,

b. the radar measurements at each time are transformed into a polar coordinate system,

c. determining a first parameter and a second parameter of each of the transformed radar measurements by means of a linear least squares polynomial fitting method,

d. and determining the occupancy state of the parking space according to the first parameter.

The term "occupancy state of a parking space" is understood to mean whether the parking space is already occupied by a motor vehicle or whether the parking space is free.

The radar measurement value contains information about the surroundings of the parking space, on the basis of which the occupancy state can be determined.

Typically, radar measurements are decomposed into an imaginary part and a real part. These radar measurements can then be transformed into a polar coordinate system. The radar measurements thus each result in a spiral shape.

The logarithmic spiral is given by the following equation:

r＝ae^bθ

where r is the spacing from the origin, and where θ is the angle relative to the abscissa. Further, a is a first parameter and b is a second parameter. In the polar coordinate system, the first and second parameters each define a center of the spiral-shaped transformed radar measured values, wherein these centers in turn jointly have a spiral shape.

It is advantageous here that this is a simple possibility for determining the occupancy state of the parking space.

In one embodiment of the method according to the invention, it is provided that the occupancy state is determined in method step d by comparing the first parameter with a threshold value, wherein the parking space is determined to be occupied when the first parameter is greater than the threshold value.

It is advantageous here that this is a simple implementation for determining the occupancy state.

In particular, first parameters are derived from the transformed radar measured values of the plurality of radar channels sensed at a time, which first parameters are averaged and subsequently compared with a threshold value in order to determine the occupancy state.

In one embodiment of the method according to the invention, it is provided that the threshold value is 1.

It is advantageous here for the threshold value to be a meaningful value which makes it possible to divide the parking space into occupied and unoccupied.

In one embodiment of the method according to the invention, method steps e and f are additionally carried out, wherein in method step e, the variance of the first and second parameters determined in method step c of the transformed radar measurement values of the radar measurement values sensed at one of the points in time is determined, and wherein in method step f, the validity of the radar measurement values sensed at this point in time is determined on the basis of the variance.

By "validity" is understood whether the radar measured values can be used with a certain degree of reliability for determining the occupancy state. If the validity is sufficient, the radar measurements can be considered correct and these can be used to determine the occupancy state. Conversely, if the effectiveness is not sufficient, it follows that: radar measurements are erroneous due to external influences or sensor faults or sensor drifts and should not be taken.

In this case, it is also conceivable to apply the polynomial fitting method again to the first and second parameters and to determine a further variance of the further parameters obtained in this case, from which further variance the validity of the radar measured values can then be determined.

It is advantageous here if, depending on the determined validity of the radar measured values, it can be concluded whether the radar measured values can be meaningfully used for further evaluation. In this case, the validity is determined quickly and easily, so that a decision can be made quickly in evaluating the radar measured values.

In one embodiment of the method according to the invention, it is provided that the validity of the radar measured values sensed at this point in time is determined in method step f by: the variance is compared with a further threshold value, wherein the validity of the radar measurement value is considered sufficient when the variance is smaller than the further threshold value.

It is advantageous here that this is a simple implementation for determining the validity of the radar measurement values.

In turn, it can be determined that: when the variance is equal to or greater than the threshold, the validity of the radar measurement is deemed insufficient.

In one embodiment of the method according to the invention, it is provided that the further threshold value is 10.

It is advantageous here for the further threshold value to be a meaningful value which divides the validity of the radar measured values into sufficient and insufficient values.

The invention further relates to a device having at least one radar sensor and a processing unit, wherein the processing unit is provided for carrying out the method according to the invention.

The invention also relates to a parking space having at least one parking space, wherein the parking space has a device according to the invention. The parking space has at least one parking space. Accordingly, the parking space is adapted for parking a motor vehicle thereon. For example, the parking space may be a common parking lot or also a parking building or parking area.

Drawings

Fig. 1 shows an embodiment of a method according to the invention;

fig. 2 shows an embodiment of the device according to the invention;

FIG. 3 shows transformed radar measurements shown in a polar plot;

fig. 4 shows a graph plotted with the first parameter over time.

Detailed Description

Fig. 1 shows an embodiment of the method according to the invention.

First, in method step a, radar measured values 22 of a plurality of radar channels are sensed at a plurality of different times in a predetermined time duration, each radar measured value 22 being composed of a real part and an imaginary part, using at least one radar sensor 20. In method step b, the sensed radar measured values 22 at the respective time are then transformed into a polar coordinate system, resulting in transformed radar measured values 23.

Next, in a method step c, a first parameter and a second parameter of the transformed radar measured values 23 are respectively determined by means of a linear least squares polynomial fitting method. The first and second parameters are the coordinates of the center of the transformed radar measurement 23, respectively. The first parameter is applied here to the abscissa direction and the second parameter to the ordinate direction.

Then, in method step d, the occupancy state of the parking space is determined as a function of the first parameter. In this case, for example, in method step d, the first parameter can be compared with a threshold value, wherein the parking space is determined to be occupied when the first parameter is greater than the threshold value. Accordingly, when the first parameter is less than or equal to the threshold, the parking space is determined to be unoccupied.

In particular, first parameters are derived from the transformed radar measured values 23 of the radar measured values 22 of the plurality of radar channels sensed at a time, which first parameters are averaged and subsequently compared with a threshold value in order to determine the occupancy state.

The threshold value can be, for example, 1.

Optionally, method step e and method step f can additionally be carried out, wherein in method step e the variance of the first and second parameters determined in method step c of the transformed radar measurement 23 of the radar measurement 22 sensed at one of the time instants is determined, and wherein in method step f the validity of the radar measurement 22 is determined from the variance determined in method step e.

For example, in method step f, the validity of the radar measured value 22 can be determined by comparing the variance with a further threshold value, wherein the validity of the radar measured value 22 is considered sufficient when the variance is smaller than the further threshold value.

The further threshold value can be, for example, 10.

Fig. 2 shows an embodiment of the device according to the invention.

An apparatus 10 is shown. The device 10 has a radar sensor 20 and a processing unit 30. The radar sensor 20 is connected to the processing unit 30 in such a way that radar measured values sensed by the radar sensor 20 can be intercepted by the processing unit 30. For this purpose, the connection can be configured both as a wired connection and as a wireless connection.

The processing unit 30 is configured such that it can carry out the method according to the invention, as shown, for example, in fig. 1.

For example, the device 10 can be arranged at a parking space of a parking space, which is not shown, and here it can monitor the occupancy state of the parking space.

Fig. 3 shows the transformed radar measurements shown in the polar diagram.

A polar coordinate system is shown. Here, the abscissa shows the real part and the ordinate shows the imaginary part. Transformed radar measurements 23 are shown, which have been transformed from radar measurements 22 sensed at a common time. In this case, each of the transformed radar measured values 23 has a center shown as a point. The center embodies the first parameter as an abscissa value and the second parameter as an ordinate value.

Fig. 4 shows a graph plotted with the first parameter over time.

A graph is shown, wherein the axis of abscissa shows the time t and the axis of ordinate shows the first parameter of the transformed radar measurement 23. Here, if the first parameter is higher than 1, it is concluded that the parking space is already occupied. Conversely, if the first parameter is below 1, it is concluded that the parking space is free.