JP2019159622A - Vehicle detection device, vehicle detection method, and vehicle detection program - Google Patents

Abstract

To prevent erroneous detection of a full/vacant state of a vehicle to a vehicle cabin.SOLUTION: A vehicle detection device 10 comprises a magnetic sensor 11 arranged on a ground surface of a vehicle cabin; a detection value acquisition part 121 for acquiring a periodic detection value based on detection at a geomagnetism level from the magnetic sensor 11; a first full/vacant state determination part 122 for determining a vacant state, when the detection value is lower than a vacancy threshold value; and a second full/vacant state determination part 123 for switching determination between a full state and a vacant state when a difference of both detection values before and after detecting a peak exceeds a predetermined difference threshold value, in a case where the peak of the detection value acquired corresponding to one region of a vehicle exceeds a full threshold value, and the detection value after the peak is converged to between the full threshold value and the vacancy threshold value.SELECTED DRAWING: Figure 5

Description

  The present invention relates to a vehicle detection technique for determining a full state of a passenger compartment such as a parking lot using a magnetic sensor.

  Conventionally, there has been known a vehicle detection device in which a magnetic sensor is installed on the ground in a passenger compartment space of a parking lot, and a change in geomagnetism caused by the presence or absence of a vehicle is detected to determine whether the passenger compartment is full or empty. ing. For example, in Patent Document 1, a plurality of magnetic sensors are installed in the vehicle width direction or the like in a vehicle interior, and a difference composite value of detection levels in the respective axial directions between the magnetic sensors is used for determination of the presence or absence of a vehicle. Therefore, even if heavy vehicles such as trucks and buses pass near the magnetic sensor, or a train overhead wire or high-voltage wire is installed near the magnetic sensor, erroneous detection is prevented. .

JP 2006-164145 A

  However, the device described in Patent Document 1 suppresses the influence of disturbance caused by the passage of a heavy object using a plurality of magnetic sensors, and the configuration becomes large because the plurality of magnetic sensors are used. In addition, the cost increases.

  As is well known, there are various types of vehicles, and depending on the type of vehicle, the degree of influence on geomagnetism is high. It's not easy. Further, when a vehicle of a vehicle type having a high influence on geomagnetism (that is, a large change in geomagnetism) stops in an adjacent vehicle compartment, the possibility of erroneous detection of the vehicle compartment increases.

  For example, in FIG. 11, (a) shows a case where the degree of influence of geomagnetism is low (the change of geomagnetism is small), and (b) shows that a vehicle having a high degree of influence of geomagnetism stops in the adjacent vehicle compartment. Shows the case. In the figure, [Z1] is the own vehicle compartment, and [Z2] is the adjacent vehicle compartment. For convenience of explanation, the magnetic sensor 11a is installed in its own compartment [Z1]. The vehicle 21 enters the own compartment [Z1], and the vehicle 22 enters the adjacent compartment [Z2]. [I], [II], and [III] indicate timings in the time axis direction. In addition, the waveform s on the lower side of each figure shows a change state of the detected value of geomagnetism in the temporal direction detected by the magnetic sensor 11a.

  In (a), the vehicle 21 approaches the vehicle compartment [Z1] at the timing [I], and the detection value s gradually increases. Next, when the engine part of the vehicle 21 enters above the magnetic sensor 11a at the timing [II], the detection value s reaches a peak, and when the entry continues further, the detection value s gradually decreases, and the stop timing. After [III], it stabilizes to a predetermined value. In this example, in the state where the vehicle compartment [Z1] is full, the detected value is less than the fullness determination threshold Lo, and is erroneously detected as an empty state.

  On the other hand, in (b), the vehicle 22 is approaching the adjacent vehicle compartment [Z2] at the timing [I], and the detection value s rises gently. Next, the detection value s may exceed the fullness determination threshold Lo before the vehicle 22 enters the vehicle compartment [Z2] at timing [II]. When the vehicle further enters, the detection value s may remain unchanged while maintaining the fullness determination threshold Lo or higher, and may stabilize at the same level after the stop timing [III]. In this example, the own compartment [Z1] is erroneously detected as full even if it is empty.

  In one aspect, the present invention has been made in view of such circumstances, and an object of the present invention is to provide a technique for preventing erroneous detection of a full vehicle state with respect to a passenger compartment.

  The present invention employs the following configuration in order to solve the above-described problems.

  That is, the vehicle detection device according to one aspect determines a vehicle full state with respect to the passenger compartment using a temporal detection value of a geomagnetic level obtained from a magnetic sensor installed on the ground of the passenger compartment. When the detection value is lower than an empty threshold value for determining an empty vehicle, the first determination means for determining that the vehicle is empty and the peak of the detection value acquired corresponding to one part of the vehicle has a predetermined full threshold value. And when the detection value after the peak converges between the full threshold and the empty threshold when the difference between both detection values before and after the detection of the peak exceeds a predetermined difference threshold, Second determining means for switching determination between a full state and an empty state.

  The vehicle detection method according to one aspect is a vehicle detection method for determining a full state of a vehicle with respect to the vehicle compartment using a time-dependent detection value of a geomagnetic level obtained from a magnetic sensor installed on the ground of the vehicle compartment. When the detected value is lower than an empty threshold value for determining an empty vehicle, a first determination step for determining an empty state and a peak of detected value acquired corresponding to one part of the vehicle has exceeded a predetermined full threshold value In the case where the detection value after the peak converges between the full threshold and the empty threshold, if the difference between the two detection values before and after the detection of the peak exceeds a predetermined difference threshold, And a second determination step for switching determination between the empty state and the empty state.

  The vehicle detection program according to one aspect uses a processor to determine whether the vehicle is full with respect to the passenger compartment by using a time-dependent detected value of a geomagnetic level obtained from a magnetic sensor installed on the ground of the passenger compartment. In the program, when the detected value is lower than an empty threshold value for determining an empty vehicle, a first determination step for determining an empty state, and a peak of the detected value acquired corresponding to one part of the vehicle is a predetermined full threshold value And when the detection value after the peak converges between the full threshold value and the empty threshold value, the difference between the two detection values before and after detection of the peak exceeds a predetermined difference threshold value. , Causing the processor to execute a second determination step of switching determination between a full state and an empty state.

  According to the above-described configuration, the movements of the passenger compartment and surrounding vehicles are acquired as detected values over time (for example, periodically) of the geomagnetic level via the magnetic sensor. When the acquired detection value is lower than an empty threshold value for determining an empty vehicle, it is determined as an empty state. On the other hand, the peak of the detection value acquired corresponding to one part of the vehicle, for example, the engine part, when the vehicle enters and leaves the passenger compartment exceeds a predetermined full threshold value, and the detection value after the peak is a full threshold value and an empty threshold value. In the case of convergence during the period, it is determined that the difference between the two detection values before and after the peak detection exceeds a predetermined difference threshold value, or it is determined to be full or empty. In this way, unlike the conventional method of determining the full state with one threshold, the determination is made by paying attention to the appearance of the peak change of the geomagnetism due to one part of the vehicle and the difference between before and after. As a result, it is possible to accurately determine the vehicle compartment for the degree of influence on geomagnetism, the presence / absence / exit of a vehicle in an adjacent vehicle compartment, and the passing of a vehicle at a nearby location.

  In the vehicle detection device according to the one aspect, the second determination unit determines that the detection value after the peak is full when the detection value after the peak is higher than the detection value before the peak, and the detection value after the peak is When it is lower than the detection value before the peak, it may be determined that an empty state is reached. According to this configuration, it is possible to accurately determine the full state and the empty state by paying attention to the peak and the magnitude of the difference.

  In the vehicle detection apparatus according to the one aspect, when the second determination unit counts the first time of the peak, the second determination unit determines whether or not the peak is reached, and counts the second time of the peak. It may be determined whether or not it is empty. According to this configuration, the full state and the empty state can be distinguished and accurately determined by the first and second peaks.

  In the vehicle detection device according to the one aspect, the second determination unit may reset the count value of the peak when a difference between both detection values before and after the detection of the peak is equal to or less than the predetermined difference threshold value. Good. According to this configuration, when the difference does not exceed the difference threshold value, there is no change in the full state, so the count value is reset and the determination process can be performed again.

  In the vehicle detection apparatus according to the one aspect, the determination unit obtains a detection value for calculating a detection value for determination using at least one detection value when a plurality of continuously acquired detection values converge. May be provided. According to this configuration, since the full space state is determined while the geomagnetism in the vehicle interior is stable, the determination accuracy is increased.

  In the vehicle detection device according to the one aspect, the magnetic sensor may be installed on a doorway side of the vehicle with respect to a central portion of the vehicle compartment. According to this configuration, a part of a vehicle having a high influence on geomagnetism, typically an engine part, etc. passes over the magnetic sensor when the vehicle enters or leaves the vehicle, so the peak is surely obtained. It can be detected.

  ADVANTAGE OF THE INVENTION According to this invention, the technique which prevents the misdetection of the vehicle full state with respect to a vehicle interior can be provided.

FIG. 1 is a diagram illustrating an example of the degree of influence on the geomagnetism on the ground surface with respect to a portion in the traveling direction of the vehicle, where (a) is a vehicle type with a low influence level and (b) is a vehicle type with a high influence level. FIG. FIG. 2 is a diagram for explaining an example of the relationship between the installation position of the magnetic sensor and the stop position of the vehicle and the degree of influence on the geomagnetism, (a) is a diagram showing the state of entering and leaving the vehicle; (B) is a time chart showing the history of detected values of geomagnetism. FIGS. 3A and 3B are diagrams for explaining vehicle full / empty determination corresponding to FIG. 2, in which FIG. 3A is a diagram showing a vehicle entering and exiting, and FIG. 3B is a history of detected values of geomagnetism. It is a time chart which shows the state of fullness determination. FIG. 4 is a diagram showing an example for explaining vehicle full / empty determination in a case where a vehicle having a high influence on geomagnetism is stopped in an adjacent passenger compartment. The figure which shows the mode of departure, (b) is a time chart figure which shows the history of the detection value of geomagnetism, and the state of fullness determination. FIG. 5 is a diagram illustrating an example of a hardware configuration of the vehicle detection device according to the embodiment. FIG. 6 is a flowchart illustrating an example of a vehicle detection processing procedure according to the embodiment. FIG. 7 is a flowchart illustrating an example of a vehicle detection processing procedure according to the embodiment. FIG. 8 is a time chart for explaining an example of vehicle fullness determination when a vehicle having a high degree of influence on geomagnetism that has stopped in the adjacent passenger compartment leaves first. FIG. 9 is a time chart for explaining an example of vehicle fullness determination when the vehicle is parked in the adjacent vehicle compartment and the own vehicle leaves first. FIG. 10 is a time chart for explaining an example of vehicle fullness determination when the vehicle passes through the passenger compartment of the host vehicle. FIGS. 11A and 11B are diagrams for explaining erroneous detection due to the magnitude of the influence on geomagnetism. FIG. 11A shows the case where the influence on geomagnetism is low (the change in geomagnetism is small), and FIG. This shows a case where a vehicle having a high influence on the vehicle stops in the adjacent passenger compartment.

  Hereinafter, an embodiment according to an aspect of the present invention (hereinafter referred to as “the present embodiment”) will be described with reference to the drawings. However, this embodiment described below is only an illustration of the present invention in all respects. It goes without saying that various improvements and modifications can be made without departing from the scope of the present invention. That is, in implementing the present invention, a specific configuration according to the embodiment may be adopted as appropriate. Although data appearing in this embodiment is described in a natural language, more specifically, it is specified by a pseudo language, a command, a parameter, a machine language, or the like that can be recognized by a computer.

<Characteristics of vehicle parts and geomagnetic changes>
FIG. 1 is a diagram illustrating an example of the degree of influence on the geomagnetism on the ground surface with respect to a portion in the traveling direction of a vehicle. FIG. FIG. In (a), the peak of the detected value of geomagnetism is shown under the engine mounting part of the vehicle 211, and the other parts are flat and relatively low. In (b), the detection value of geomagnetism higher than that in (a) is shown for the entire area of the vehicle 212, but the lower part of the engine mounting portion shows a change in relatively high peak geomagnetism, as in (a). Is shown. As described above, the peak of the detected value of the geomagnetism appears in a vehicle under a predetermined part in the traveling direction, for example, an engine mounting part, regardless of the vehicle type.

  FIG. 2 is a diagram for explaining an example of the relationship between the installation position of the magnetic sensor and the stop position of the vehicle and the degree of influence on the geomagnetism, (a) is a diagram showing the state of entering and leaving the vehicle; (B) is a time chart showing the history of the detected value s of geomagnetism. FIG. 2 shows a detected value s of geomagnetism when the vehicle 21 described in FIG. 1 enters and exits the passenger compartment [Z1]. Moreover, as shown in FIG. 2, the magnetic sensor 11 is installed in the entrance / exit side with respect to the center part of the parking position of vehicle interior [Z1]. The configuration of the magnetic sensor 11 will be described later with reference to FIG.

  In FIG. 2, when the vehicle 21 approaches the vehicle compartment [Z1] at timing [I], the geomagnetic detection value s gradually increases from a low level. Next, when the engine part of the vehicle 21 enters above the magnetic sensor 11 at timing [II], the detected value s reaches the peak Sp1, and further continues, the detected value s gradually decreases. It stabilizes to a predetermined value at the stop timing [III]. On the other hand, after the timing [III], when the vehicle 21 starts back and leaves the vehicle compartment [Z1], the engine part of the vehicle 21 passes over the magnetic sensor 11 in the reverse direction. When the detection value s reaches the peak Sp2 at the timing [IV] and continues further back, the detection value gradually decreases, and the detection value returns to the original low level at the timing [V] when the vehicle exits the passenger compartment [Z1]. Return.

  Thus, as shown inside the dashed frame in FIG. 2 (b), the detected value s once stabilizes at a higher level than before the peak Sp1 via the peak Sp1 when entering the vehicle. Can be determined as full. On the other hand, when the vehicle leaves the vehicle, the vehicle gradually decreases from a high level to a lower level than before the peak Sp2 via the higher peak Sp2, and can be determined as an empty vehicle. As described above, a temporary peak of the detected value appears when entering and leaving the vehicle to determine whether the vehicle is full, and this peak phenomenon is used.

<Characteristics of geomagnetic change by magnetic sensor>
FIGS. 3A and 3B are diagrams for explaining vehicle full / empty determination corresponding to FIG. 2, in which FIG. 3A is a diagram showing a vehicle entering and exiting, and FIG. 3B is a history of detected values of geomagnetism. It is a time chart which shows the state of fullness determination.

  In FIG. 3B, the sky threshold Le is a preset level for determining that the vehicle is an empty vehicle. The full threshold value Lf is a preset level for detecting a temporary peak of a detection value that occurs when the vehicle 21 enters or leaves the passenger compartment [Z1]. Further, the difference between the detected values before and after the peak is detected is used as a threshold for determining a change in the full state of the vehicle 21, that is, a state change from the full state to the empty state or from the empty state to the full state. A difference threshold is set in advance. By adopting the difference threshold value, it is possible to appropriately determine whether the sky is full, regardless of the type of vehicle, and even when a vehicle having a high influence on geomagnetism stops in the adjacent passenger compartment.

  In the present embodiment, the detected value of the geomagnetism is based on the level of geomagnetism detected by the magnetic sensor 11 and below the sky threshold Le in the empty state as a reference value, and the level of geomagnetism detected at present. The difference value. Further, in the present embodiment, the fullness determination of the vehicle is performed using the detection value in a stable state. Here, the stable state refers to, for example, a case where the detection values for a plurality of consecutive times converge within a predetermined range, and the detection value in the stable state is obtained, for example, by averaging them or a part thereof. Or a recent value.

  First, the detection value a is acquired in a state where no vehicle exists in the vehicle compartment [Z1] and the vehicle is completely empty. Thereafter, the vehicle 21 approaches at timing [I], and the detection value s gradually increases. When the vehicle 21 proceeds directly to the vehicle compartment [Z1] and the engine part of the vehicle 21 is positioned on the magnetic sensor 11 at the timing [II], the detected value s reaches a peak, and then passes over the magnetic sensor 11. Decrease gradually according to. Thereafter, it is acquired as a stable detection value b.

  The presence of the peak can be determined by, for example, taking the difference between the previous value and the current value every time the detection value s is acquired, and detecting the change in polarity. As another example of determination, it can also be determined by detecting that the detection value s once exceeds the full threshold value Lf and then again becomes equal to or less than the full threshold value Lf. The peak value is compared with the full threshold value Lf. If the peak value is greater than or equal to the full threshold value Lf, the number of times is counted, and the presence of the peak is used for subsequent determination. In the empty state, the count value is 1.

  Next, at timing [III], the vehicle enters the vehicle compartment [Z1] and stops. Therefore, the detection value s is stably acquired as the detection value b. When the first peak is detected and the detection value b after the peak detection is stable at least at a level equal to or higher than the empty threshold Le (or between the empty threshold Le and the full threshold Lf), the value immediately before the first peak is detected. The difference (b−a) between the stable detection value a and the stable detection value b after the peak is calculated (or calculated as an absolute value), and is compared with a predetermined difference threshold value. If the calculated difference is greater than or equal to the difference threshold, it is determined that the vehicle is present, that is, full. Otherwise, the count value is reset and remains empty.

  When the parked vehicle 21 starts leaving at the timing [IV] after being changed to the full state, the detection value A (= stable detection value b) acquired in response thereto increases gradually. A peak is detected when the engine part of the vehicle 21 passes over the magnetic sensor 11 on the way. The presence of a peak is determined by taking the difference between the previous value and the current value, for example, and detecting the change in polarity as described above. The peak value is compared with the full threshold value Lf, and when the peak value is greater than or equal to the full threshold value Lf, the number of times is counted. Here, the count value is incremented to a value of 2.

  Next, when the vehicle 21 completely leaves the passenger compartment [Z1] at timing [V], the value acquired as the detection value B is stabilized.

  At this time, as shown in FIG. 3B, if the detection value B is reduced to the empty threshold value Le or less, it can be immediately determined that the state is empty. On the other hand, when the detection value B is between the empty threshold value Le and the full threshold value Lf, the detection of the second peak and the stability of the detection value B after the peak detection are received, and immediately before the second peak. A difference (A−B) between the stable detection value A and the stable detection value B after the peak is calculated (or calculated as an absolute value), and is compared with a predetermined difference threshold value. If the calculated difference is greater than or equal to the difference threshold, it is determined that the vehicle has left and is in an empty state. Otherwise, the count value is reset and remains empty. That is, the difference threshold is a threshold for distinguishing whether or not the own vehicle 21 has entered or exited with the peak detection in between.

  FIG. 4 is a diagram showing an example for explaining vehicle full / empty determination when a vehicle having a high influence on geomagnetism is stopped in the adjacent passenger compartment. FIG. The figure which shows the mode of a vehicle, (b) is a time chart figure which shows the history of the detection value of geomagnetism, and the state of fullness determination. 4 assumes a parking lot or the like in which a plurality of vehicle compartments [Z1], [Z2],... For convenience of explanation, the magnetic sensor of the adjacent vehicle compartment [Z2] is omitted.

  First, detection from the magnetic sensor 11 installed in the vehicle compartment [Z1] when the vehicle [Z1] and [Z2] are empty and the vehicle 22 is close to the vehicle compartment [Z2] at the timing [I]. The value s gradually increases. The vehicle 22 enters the passenger compartment [Z2] as it is and stops in the passenger compartment [Z2]. The detected value s from the magnetic sensor 11 gradually increases after the timing [I], and the vehicle 22 has a great influence on the geomagnetism. Has been acquired.

  Next, at the timing [II], the vehicle 22 is heading toward the passenger compartment [Z1], enters at the timing [III], and stops at the timing [IV] through the first peak as in FIG. . The detection value b stabilized after the peak is stable at a level of at least the empty threshold value Le, for example, as in FIG. Then, it is determined whether or not the passenger compartment [Z1] has become full through detection of the peak from the detection values a and b before and after the peak, and further determining whether or not the full threshold value Lf is exceeded. Here, assuming that the vehicle is full, two cars are parked side by side as shown in timing [IV].

  Thereafter, at timing [V], only the vehicle 21 backs and starts leaving. When the vehicle 21 starts leaving the vehicle, the detected value A acquired in response thereto increases gradually as in FIG. 3, and the peak is reached when the engine part of the vehicle 21 passes over the magnetic sensor 11 on the way. To detect. Next, the car is completely departed at timing [VI]. The detection value B after the peak is stable between the empty threshold value Le and the full threshold value Lf. Here, as in FIG. 3, the detection of the peak from the detection values A and B before and after the peak, and the determination whether it is between the empty threshold Le and the full threshold Lf, the vehicle compartment [Z1] becomes empty. Is determined. Here, it is determined that the state is empty.

<[Hardware configuration]
FIG. 5 is a diagram illustrating an example of a hardware configuration of the vehicle detection device according to the embodiment. The vehicle detection device 10 is installed corresponding to a vehicle compartment, and based on detection data periodically transmitted from the magnetic sensor 11 that detects geomagnetism and the magnetic sensor 11, the vehicle full state in the corresponding vehicle compartment is detected. A determination processing module 12 is provided as determination means for performing determination processing. Moreover, the vehicle detection apparatus 10 may include a communication module 13 that transmits a determination processing result to the management server 100 via a wired or wireless connection. In addition, the management server 100 is provided as necessary, and performs, for example, operation management of the entire parking lot from the determination processing contents in each vehicle compartment.

  The magnetic sensor 11 is installed on an appropriate place in the space of the passenger compartment [Z], for example, on the ground near the vehicle entrance from the central portion or the central portion. The magnetic sensor 11 includes an AD conversion unit 111 that converts a detected signal into a digital value in addition to a sensor portion that detects magnetism, as an integrated module, or as a separate unit. As an example, a sensor portion that can detect geomagnetism in every three axial directions is adopted. In the present embodiment, data obtained by synthesizing components in three axis directions may be employed, or a mode in which predetermined one-axis or two-axis detection data is employed may be employed.

  The determination processing module 12 includes a CPU (Central Processing Unit), a RAM (Random Access Memory), a ROM (Read Only Memory), and the like, and controls each component according to information processing. The storage unit 120 is, for example, an auxiliary storage device such as a hard disk drive or a solid state drive, and stores a vehicle detection processing program executed by the determination processing module 12 and various data necessary for the processing.

  In the determination processing module 12, the vehicle detection processing program is expanded in the RAM and executed by the CPU to control each component. Thus, as shown in FIG. 5, the determination processing module 12 according to the present embodiment includes a detection value acquisition unit 121, a first full state determination unit 122, and a second full state determination unit 123. Yes. The second full state determination unit 123 includes a peak determination unit 124 and a difference determination unit 125.

  The detection value acquisition unit 121 calculates a detection value as a value for the above-described reference value from magnetic data detected by the magnetic sensor 11 that is periodically input. In addition, the detection value acquisition unit 121 detects a change in the value acquired continuously a plurality of times, determines whether or not the change is within a predetermined range, and if it is within the determination, determines that it is in a stable state. And the value in the stable state is obtained as the detected value of the stable state as described above. The process performed by the detection value acquisition unit 121 may be performed by the first full state determination unit 122 and the second full state determination unit 123, respectively. Alternatively, when the magnetic sensor 11 has a configuration including a CPU, a RAM, and a ROM, the process performed by the detection value acquisition unit 121 may be performed on the magnetic sensor 11 side.

  The first full state determination unit 122 detects whether or not the detected value of the stable state is equal to or less than the empty threshold value Le, and determines that the state is empty when it is equal to or less than the empty threshold value Le.

  The peak determination unit 124 determines whether or not the detected value exceeds the full threshold value Lf and a temporary peak is formed. The peak determination unit 124 increments an internal counter that counts a peak to 1 when the detected value passes a peak from an empty state. Further, the peak determination unit 124 increments the internal counter to be counted to 2 when the peak has passed from the full state. Furthermore, the peak determination unit 124 resets the internal counter when the difference (A−B) between the detected values in the stable state before and after the peak after passing the peak exceeds the difference threshold. The peak determination unit 124 resets the internal counter when the difference (b−a) or (A−B) between the detected values in the stable state before and after the peak after passing through the peak is equal to or smaller than the difference threshold value. Then, it waits for the appearance of those peaks again and detects them.

  The difference determination unit 125 compares the difference (b−a) or (A−B) between the detected values in a stable state before and after the peak and the difference threshold, and the difference is set to the difference threshold. When it exceeds, it detects that the vehicle has entered and exited. That is, when the vehicle enters the passenger compartment, the engine part once passes over the magnetic sensor 11, and when the vehicle leaves the passenger compartment, the engine part temporarily changes to the magnetic sensor 11. Judge that it passed above.

  Then, when the peak is detected and the difference exceeds the difference threshold, the second full empty state determination unit 123 determines that the passenger compartment is full or empty.

<Operation example>
6 and 7 are flowcharts illustrating an example of a vehicle detection processing procedure according to the embodiment. Note that the processing procedure described below is merely an example, and each processing may be changed as much as possible. Further, in the processing procedure described below, steps can be omitted, replaced, and added as appropriate according to the embodiment.

  This flowchart is repeatedly executed, for example, at a predetermined cycle. In this flowchart, for example, it is assumed that the vehicle interior [Z] is in an empty state, geomagnetic data detected from the magnetic sensor 11 is received, and a detected value of geomagnetism is calculated based on the received data (step) S1). Next, it is determined whether or not the detected value is equal to or lower than the empty threshold value Le (step S3). If the detected value is equal to or lower than the empty threshold value Le, acquisition as the stable state a is performed (step S31), and the empty state is detected. Determination is made (step S33).

  On the other hand, if the detected value is not less than or equal to the empty threshold value Le in step S3, it is determined whether or not the detected value is greater than or equal to the full threshold value Lf (step S5), and if not, whether or not the full threshold value Lf has been exceeded once. That is, it is determined whether or not the count value is 1 (step S7). Otherwise, it is determined whether or not the full threshold value is exceeded twice (step S9).

  Hereinafter, the processing of this flowchart will be described assuming the state from the timing [1] in FIG. First, since the vehicle 21 enters the passenger compartment [Z1], the detection value gradually increases every detection, exceeds the empty threshold value Le, and is detected between the full threshold value Lf and the empty threshold value Le. Accordingly, the detected value at this time is determined as No in step S9 and is acquired as the stable state a (step S11). Thereafter, when the full threshold value Lf is exceeded around timing [II] in FIG. 3 (Yes in step S5), it is determined whether or not acquisition of the stable state b has been completed (step S51). If acquisition of the stable state b is not completed, acquisition as the stable state b is performed (step S53), and the value b is further replaced with the value A (step S55). Note that if the detected value is equal to or greater than the full threshold value Lf and the acquisition of the stable state b is completed, the detection value is passed through (Yes in step S51).

  Subsequently, when the engine part of the vehicle 21 passes over the magnetic sensor 11, the detection value starts to gradually decrease, the detection value becomes equal to or less than the full threshold value Lf (No in step S5), and it is determined that the full threshold value has been exceeded once. (Yes in step S7). In step S71, it is determined whether or not acquisition of the stable state b has been completed. If acquisition of the stable state b has not been completed, acquisition of the stable state b is performed (step S73). Subsequently, the difference (b−a) between the values of the stable state before and after the peak is calculated, the difference is compared with the difference threshold (step S75), and if the difference exceeds the difference threshold, the difference is satisfied. The state is determined (step S77). On the other hand, if the difference is less than or equal to the difference threshold, the number-of-times information exceeding the full threshold Lf is reset (step S79).

  Moreover, if acquisition of the stable state b is completed in step S71, a detected value is acquired as the stable state A (step S81).

  Subsequently, when the vehicle 21 begins to leave at the timing [IV] in FIG. 3, the engine part approaches the magnetic sensor 11, and the detection value gradually increases toward the full threshold Lf. Until the detected value exceeds the full threshold value Lf (Yes in step S7), the processes after step S71 are executed. Then, while the detected value exceeds the full threshold value Lf (Yes in step S5), the process is passed.

  Thereafter, when the engine part of the vehicle 21 passes over the magnetic sensor 11 and gradually decreases below the full threshold value Lf (Yes in step S9), the count value is incremented to 2 because the full threshold value Lf has been exceeded twice, and the stable state is reached. B is acquired (step S91). Next, the difference (A−B) between the stable states A and B before and after the second peak is calculated and compared with the difference threshold value (step S93). If the difference (A−B) exceeds the difference threshold, it is determined that the state is empty (step S95), and the number of times that the full threshold is exceeded is reset (step S97).

  On the other hand, if the difference (A−B) is less than or equal to the difference threshold value in step S93, the full state is maintained (step S99), and then the state exceeding the second full threshold value is ignored and the second time is exceeded. In other words, the stable state B is updated as the stable state A, and the discarding process of the stable state B is performed (step S103). In addition, when the vehicle 21 leaves the passenger compartment [Z1] and the level of the stable state becomes equal to or lower than the empty threshold value Le (Yes in step S3), it is processed as acquisition of the stable state a (step S31). It is determined that the state is empty (step S33).

<Other application examples>
FIG. 8 is a time chart for explaining an example of vehicle fullness determination when a vehicle having a high degree of influence on geomagnetism that has stopped in the adjacent passenger compartment leaves first. Timings [I] to [IV] in FIG. 8 are the same as those in FIG.

  When the vehicle 22 in the compartment [Z2] leaves the vehicle at the timing [V] following the timing [IV], unlike the case where the vehicle 21 leaves from the own vehicle compartment [Z1], the magnetic sensor 11 Since the engine part of the vehicle does not pass above, the detected value gradually decreases and stabilizes without appearing a peak. Therefore, even if the vehicle 22 having a high influence on geomagnetism leaves the adjacent vehicle compartment [Z2], the full state determination for the vehicle compartment [Z1] does not cause an erroneous determination.

  FIG. 9 is a time chart for explaining an example of vehicle fullness determination when the vehicle is parked in the adjacent vehicle compartment and the own vehicle leaves first. Timings [I] to [III] in FIG. 9 are the same as those in FIG.

  At the timing [IV] following the timing [III], the vehicle 22 is parked in the adjacent vehicle compartment [Z2]. Therefore, the detected value increases between the empty threshold value Le and the full threshold value Lf. Next, when the vehicle 21 starts to leave the passenger compartment [Z1], the detected value detects the second peak because the engine part of the vehicle 21 passes over the magnetic sensor 11 at the timing [V]. Thereafter, at timings [V] to [VI], the detected value gradually decreases and stabilizes between the empty threshold value Le and the full threshold value Lf. In addition, since the detected value decreases as the vehicle 21 in the passenger compartment [Z1] is removed, the difference (B−A) is equal to or greater than the difference threshold value, so it is reliably detected that the vehicle 21 has left the vehicle. Therefore, even if the vehicle 22 having a high influence on geomagnetism is parked in the adjacent vehicle compartment [Z2], an erroneous determination on the departure of the vehicle 21 from the vehicle compartment [Z1] is not caused.

  FIG. 10 is a time chart for explaining an example of vehicle fullness determination when the vehicle passes through the passenger compartment of the host vehicle. In FIG. 10, since the vehicle 22 is parked in the adjacent passenger compartment [Z2], the detected value is at a higher level. Next, when the vehicle 21 passes through the passenger compartment [Z1] at timings [II] to [IV], the peak appears because the engine part of the vehicle 21 passes over the magnetic sensor 11 at timing [III]. ing. However, since there is no difference in the difference between the detection values before and after the peak, there is no erroneous determination that the difference (b−a) is equal to or less than the difference threshold value and the empty state is switched to the full state.

  This is because even if a vehicle having a large influence on geomagnetism such as a large truck passes immediately nearby, there is no difference between the detected values before and after passing, so that a peak exceeding the full threshold Lf is temporarily detected. In addition, by applying the difference threshold, it is possible to prevent erroneous determination with respect to the full state.

<Action and effect>
As described above, in this embodiment, instead of the conventional method of determining the full state with one threshold, the full state of the vehicle is represented by the occurrence of a peak change in geomagnetism caused by one part of the vehicle. , And the difference between the detected values before and after that and the difference threshold, the determination is made so that the degree of influence on the geomagnetism of the other vehicle, whether there is a vehicle in the adjacent vehicle compartment, It is possible to accurately determine the passenger compartment even when entering and exiting and passing through a nearby vehicle.

  The present invention is not limited to the above-described embodiment as it is, and can be embodied by modifying the constituent elements without departing from the scope of the invention in the implementation stage. Moreover, various inventions can be formed by appropriately combining a plurality of constituent elements disclosed in the embodiment. For example, some components may be deleted from all the components shown in the embodiment. Furthermore, you may combine suitably the component covering different embodiment.

  Furthermore, the correspondence between the configuration according to the present invention and the configuration according to the above-described embodiment can be described as in the following supplementary notes.

<Appendix>
In the vehicle detection device (10) for determining a full state of the vehicle with respect to the passenger compartment using a temporal detection value of the geomagnetic level obtained from the magnetic sensor (11) installed on the ground of the passenger compartment,
First determination means (122) for determining an empty state when the detected value is lower than an empty threshold for determining an empty vehicle;
When the peak of the detection value acquired corresponding to one part of the vehicle exceeds a predetermined full threshold value, and when the detection value after the peak converges between the full threshold value and the empty threshold value, A vehicle detection device (10) comprising: a second determination unit (123) that switches a determination between a full state and an empty state when a difference between both detection values before and after the detection of the peak exceeds a predetermined difference threshold value. ).

DESCRIPTION OF SYMBOLS 10 Vehicle detection apparatus 11 Magnetic sensor 12 Data processing module 121 Detection value acquisition part 122 1st full state determination part (1st determination means)
123 2nd full state determination part (2nd determination means)
124 peak determination unit 125 difference determination unit 13 communication module
[Z], [Z1] Cabin 21, 22 Vehicle

Claims (8)

In the vehicle detection device for determining the full state of the vehicle with respect to the passenger compartment using a temporal detection value of the geomagnetic level obtained from a magnetic sensor installed on the ground of the passenger compartment,
First detection means for determining an empty state when the detected value is lower than an empty threshold value for determining an empty vehicle;
When the peak of the detection value acquired corresponding to one part of the vehicle exceeds a predetermined full threshold value, and when the detection value after the peak converges between the full threshold value and the empty threshold value, A vehicle detection apparatus comprising: a second determination unit that switches a determination between a full state and an empty state when a difference between both detection values before and after the detection of the peak exceeds a predetermined difference threshold.   When the detection value after the peak is higher than the detection value before the peak, the second determination means determines that the full state is reached, and when the detection value after the peak is lower than the detection value before the peak, The vehicle detection device according to claim 1, wherein it is determined that the vehicle is in an empty state.   The second determination means determines whether or not the peak is full when the first time of the peak is counted, and determines whether or not the peak is empty when the second time of the peak is counted. The vehicle detection device according to claim 1 to be performed.   The vehicle detection device according to claim 3, wherein the second determination unit resets the peak count value when a difference between both detection values before and after detection of the peak is equal to or less than the predetermined difference threshold.   The determination unit includes a detection value acquisition unit that calculates a detection value for determination using at least one detection value when a plurality of continuously acquired detection values converge. The vehicle detection device according to any one of the above.   The vehicle detection device according to claim 1, wherein the magnetic sensor is installed on a doorway side of the vehicle with respect to a central portion of the vehicle compartment. In the vehicle detection method for determining the fullness of the vehicle with respect to the passenger compartment by using a temporal detection value of the geomagnetic level obtained from a magnetic sensor installed on the ground of the passenger compartment,
A first determination step for determining an empty state when the detected value is lower than an empty threshold for determining an empty vehicle;
When the peak of the detection value acquired corresponding to one part of the vehicle exceeds a predetermined full threshold value, and when the detection value after the peak converges between the full threshold value and the empty threshold value, A vehicle detection method comprising: a second determination step that switches a determination between a full state and an empty state when a difference between both detection values before and after the detection of the peak exceeds a predetermined difference threshold. In a vehicle detection program for determining whether the vehicle is full with respect to the passenger compartment by means of a processor, using a value detected over time of a geomagnetic level obtained from a magnetic sensor installed on the ground of the passenger compartment,
When the detected value is lower than an empty threshold value for determining an empty vehicle, a first determination step for determining an empty state, and a peak of the detected value acquired corresponding to one part of the vehicle exceeds a predetermined full threshold value In the case where the detection value after the peak converges between the full threshold and the empty threshold, if the difference between the two detection values before and after the detection of the peak exceeds a predetermined difference threshold, The vehicle detection program which makes the said processor perform the 2nd determination step which switches the determination between an empty state.