Method for determining an occupancy status of a parking bay and for determining the occupancy statuses of several parking bays along a street

Abstract

The invention relates to a method for determining an occupancy status of a parking bay, wherein a vehicle is moved along a street segment with at least one parking bay and the vehicle has a distance sensor as well as a sensor for satellite-based location and time determination. Furthermore, static parking information on the position of the parking bays in a street segment and parking information on the parking bays are on hand. By means of distance and location data projected distance data are produced which each indicate a distance datum of the distance sensor to the next object in the sensor direction at a point of the street of the street segment at the parking bay. By means of these projected distance data a standard distance is ascertained. Subsequently, for each point of a parking bay the determination is made if this is unoccupied by comparing the distance datum with the standard distance plus a delta. An area of a parking bay is determined as one or several vacant parking spaces if the rounded-down quotient of the length of the adjoining contiguous unoccupied points to the length of an average parking space is 1 or greater.

Claims

1. A method for determining an occupancy status of a parking bay, wherein a vehicle is moved along a street segment with at least one parking bay, the method comprising: wherein the vehicle has a distance sensor configured to generate distance data, and being aligned laterally to a curbside, and a sensor for satellite-based location and time determination, by means of which distance and location data are recorded during movement of the vehicle along the street segment, wherein the distance data of the distance sensor represent the distance from the distance sensor to a next object along a sensor direction of movement of the distance sensor, wherein static parking information data on positions of parking bays in the street segment and parking information on each said parking bay are on hand, using the distance and location data to ascertain projected distance data arranged along the parking bay, which each indicate a distance datum of the distance sensor to the next object in the sensor direction at a point on the street of the street segment at the parking bay, wherein the projected distance data take into account a course of the street segment by projecting the location data on the course of the street segment and adjusting the distance data accordingly, using the projected distance data of the parking bay to ascertain a standard distance d.sub.s, and in that a point of a parking bay is determined as unoccupied if the distance datum of this point is greater than the standard distance plus a delta Δ, in that an area of a parking bay is determined as one or several vacant parking spaces if a rounded-down quotient of a length of adjoining contiguous unoccupied points to a length of an average parking space is 1 or greater.

2. The method according to claim 1, wherein the projected distance data are ascertained equidistantly along the parking bay.

3. The method according to claim 1, wherein data on the course of the street segment are on hand which are used to produce the projected distance data.

4. The method according to claim 1, wherein missing distance and/or location data are interpolated for the projected distance data.

5. The method according to claim 1, further comprising: to ascertain the standard distance d.sub.s, a distance histogram of the projected distance data of the parking bay is used.

6. The method according to claim 5, wherein as the standard distance d.sub.s, a first maximum of the distance histogram is used which has a distance of at least 1 meter.

7. The method according to claim 5 wherein as the standard distance d.sub.s, a first maximum of the distance histogram is used which amounts to at least 10% of a highest maximum.

8. The method according claim 5, wherein as the standard distance d.sub.s, a first maximum of the distance histogram is used which has at least 10% of a surface of the distance histogram.

9. The method according to claim 5, wherein as the standard distance d.sub.s, 5 meters is set when no distinct standard distance d.sub.s can be ascertained by means of the projected distance data.

10. The method according to claim 5, wherein a length of an average parking space of a parking bay is present in the static parking information data.

11. The method according to claim 5, wherein as the standard distance d.sub.s, a first maximum of the distance histogram is used.

12. The method according to claim 1, wherein the delta Δ is determined by way of the static parking information data of the parking bay.

13. The method according to claim 1, wherein as the distance sensor, a LIDAR sensor is used.

14. The method according to claim 1, as the distance sensor a 1-D LIDAR sensor is used.

15. The method according to claim 1, further comprising: forwarding the distance and location data to a remotely arranged computer unit, in that a storage is provided, in which the static parking information data is present and using the computer unit to calculate the projected distance data, the standard distance d.sub.s and the determination of a parking state of the parking bay.

16. The method according to claim 1, wherein the method is carried out separately for each one of a plurality of parking bays present along the street segment.

Description

BRIEF DESCRIPTION OF DRAWINGS

(1) The invention is explained in greater detail hereinafter by way of schematic exemplary embodiments with reference to the Figures, wherein:

(2) FIG. 1 is a schematic view of the situation when ascertaining distance and location data;

(3) FIG. 2 is a schematic illustration of the ascertained distance data;

(4) FIG. 3 is a distance histogram of the ascertained distance data; and

(5) FIG. 4 is a schematic illustration following evaluation of the data.

DETAILED DESCRIPTION

(6) In the following the method according to the invention is explained in greater detail with reference to FIGS. 1 to 4.

(7) As a first step according to the method pursuant of the invention a vehicle 10 equipped with a sensor device 12, which can be a 1D LIDAR sensor for example, and a GPS sensor 14. The vehicle 10 travels along a street segment in which at least one parking bay 20 is present. Within the meaning of the invention, a parking bay 20 can in particular be understood as an area in which contiguous parking is possible. In other words, this is an uninterrupted area in which parking spaces 24 are located. Another term for this would be parking lot.

(8) With its sensor direction 13, the LIDAR sensor 12 is aligned laterally to the curbside, ideally in a substantially orthogonal manner to the direction of travel of the vehicle 10.

(9) The vehicle 10 is moved on a street 21 along the parking bay 20. The parking bay 20 illustrated here is partially occupied. In the parking bay 20 three vehicles 23 as well as one vacant parking space 24 are located.

(10) As the vehicle 10 travels past the parking bay 20, what is ascertained by means of the LIDAR sensor 12 and the GPS sensor 14 are on the one hand distance data concerning the distance between the LIDAR sensor 12 and the next object, for instance the vehicle 23 or a house wall situated behind, and at the same time corresponding location data in order to localize the measurement. Synchronization can in this case be implemented by way of a joint time stamp, for example.

(11) In FIG. 2 the distance data d ascertained by means of the LIDAR sensor 12 are illustrated along the street segment. It can be seen that different distances d are on hand for different positions s. On the basis of these different distances d, ascertainment is now made by way of the method according to the invention if a vacant parking space is present or not.

(12) However, before this evaluation can be carried out, projected distance data that are distributed equidistantly, e.g., in 5 cm steps, along the parking bay 20 are produced from the data ascertained by means of the LIDAR sensor 12 and the GPS sensor 14. To this end, it is partly necessary to take the mean of the corresponding data or rather project these to an ideal line along the parking bay. For this purpose, it may be helpful if data on the course of the street are on hand. This step is advantageous to increase accuracy but is not absolutely necessary.

(13) Finally, data are present in a form as shown in FIG. 2. In order to ascertain in the next step if each point or each position along the parking bay is occupied or unoccupied, the standard distance d.sub.s is initially ascertained in accordance with the invention. This is a value that provides information on the average distance between the vehicle 10 passing by and parked vehicles 23 in the parking bay 20. This can be implemented in several ways. According to the invention this can, for example, be implemented as set out in the following with reference to FIG. 3. FIG. 3 depicts a distance histogram 30 of the projected distance values along the parking bay 20. In the histogram 30 the number of measurements n with a certain distance d is shown. According to the invention, the standard distance d.sub.s is, for example, set to the value of the first maximum that has a distance of at least 1 m. This can be additionally refined in that the further requirement is that this maximum has a minimum size compared to other existing maxima or also a minimum surface. Within the meaning of the invention the minimum surface can be ascertained, for example, by dividing the histogram into individual subareas that each have a width of 20 cm for example, i.e., from 0 to 20 cm, from 20 to 40 cm and so on. For a maximum used to define the standard distance d.sub.s, the surface present below the curve of the histogram 30 then has to have a corresponding minimum value that, for example, amounts to 10% of the entire surface of the distance histogram.

(14) The standard distance d.sub.s ascertained accordingly is drawn in FIG. 2. Next, the delta Δ is ascertained in accordance with the invention. This depends on the parking orientation within the parking bay 20. By way of the delta Δ, it is taken into account whether parking in the parking bay is, e.g., parallel, orthogonal or diagonal to the course of the street. The parking orientation is ascertained from the existing static parking information on the respective parking bay. In the European region, for example, values of 3 meters for parallel parking orientation, 4 meters for orthogonal parking orientation and 3.5 meters for diagonal parking orientation can be used. In North America, where most parking spaces are considerably larger, correspondingly higher values are assumed.

(15) Subsequently, a rating distance d.sub.e is ascertained by adding the standard distance d.sub.s and the corresponding delta Δ.
d.sub.e=d.sub.s+Δ

(16) For each point along the parking bay 20 a comparison is now made as to whether the projected distance value d is greater or smaller than d.sub.e. If this is greater than d.sub.e, then this point is determined as unoccupied. If, however, it is smaller or equal to d.sub.e, then it is ascertained as occupied.

(17) In order to subsequently ascertain from this information if a parking space is vacant or a parking bay is occupied, an additional evaluation has to be carried out. This is now explained in greater detail with reference to FIG. 4.

(18) To find a vacant parking space 24, according to the invention the length of adjoining points detected as being vacant is set in relation to the average length of a parking space and the result is rounded down.

(19) The average length of a parking space also results from the static parking information on a parking bay 20, as it must also be taken into account here in which orientation parking is allowed in this parking bay. For parallel parking in Europe, for example, a length of 5.5 meters, for orthogonal parking a length of 2.5 meters and for diagonal parking a length of 3 meters is assumed.

(20) According to the result of this evaluation it can thus be ascertained, as illustrated in FIG. 4, where a vehicle 23 is parked in the parking bay 20 and which spaces in the parking bay 20 can be detected as vacant parking spaces 24.

(21) By way of the method according to the invention it is thus possible to easily produce highly accurate information on the parking state of parking spaces.