Event detection device and event detection method

Abstract

To enable a more accurate and simpler determination of whether an event detected based on vehicle acceleration is a true event.SOLUTION: An event detection device (event detection unit 20) includes: an acceleration acquisition unit 21 that acquires acceleration; a detection unit 22 that detects an event based on the acceleration; a speed acquisition unit 23 that acquires speed; and a determination unit 25 that determines whether an event is a true event based on a difference between an average value of the speed in a period before the event and an average value of the speed in a period after the event.SELECTED DRAWING: Figure 2

Description

Technical Field

[0001] The present disclosure relates to an event detection device and an event detection method.

Background Art

[0002] Conventionally, a technique for detecting an event such as an accident based on acceleration acquired by an information recording device installed in a vehicle is known (see, for example, Patent Documents 1-4). Patent Document 1 discloses calculating first and second moving average values of different systems over time based on vehicle acceleration data in order to determine a trigger regardless of road surface conditions, and generating a trigger signal according to a comparison result between these difference values and a threshold value. Patent Document 2 discloses transmitting vehicle behavior information to the outside when the acceleration acquired by an in-vehicle device exceeds a threshold value.

[0003] Patent Document 3 discloses that when the measured acceleration measured by an acceleration sensor is within a predetermined range, a drive recorder calculates the calculated acceleration of the vehicle during a period from the time when the measured acceleration is within the range until a predetermined time has elapsed. When the calculated acceleration is greater than a threshold value, the drive recorder is disclosed to transmit image data captured during a storage period including a reference time.

[0004] Patent Document 4 discloses that when a travel recording module determines that the acceleration measured by an acceleration sensor is within an abnormal range, it notifies a server of a dangerous driving time when the acceleration within the abnormal range was measured. When the travel recording module receives a video transmission request from the server including a dangerous driving time, it transmits to the server the captured moving image data during a predetermined period including the dangerous driving time included in the video transmission request among the recorded captured moving image data.

[0005] As described above, there is a demand for the development of a technique that can more accurately and simply determine whether an event detected based on the acceleration of a vehicle is a true event caused by an accident or the like.

Prior Art Documents

Patent Documents

[0006]

Patent Document 1

Patent Document 2

Patent Document 3

Patent Document 4

Summary of the Invention

Problems to be Solved by the Invention

[0007] The present disclosure aims to more accurately and simply determine whether an event detected based on the acceleration of a vehicle is a true event or not.

Means for Solving the Problems

[0008] To achieve the above object, an event detection device of the present disclosure is an event detection device that detects a predetermined event, and includes an acceleration acquisition unit that acquires the acceleration of a vehicle, a detection unit that detects an event based on the acceleration, a speed acquisition unit that acquires the speed of the vehicle, and a determination unit that determines whether the event detected based on the acceleration is a true event or not based on the difference between the average value of the speed in the period before the event and the average value of the speed in the period after the event.

Effects of the Invention

[0009] The event detection device of the present disclosure configured as described above can more accurately and simply determine whether an event detected based on the acceleration of a vehicle is a true event or not.

Brief Description of the Drawings

[0010]

Figure 1

Figure 2

Figure 3

Figure 4

Figure 5

Figure 6

MODE FOR CARRYING OUT THE INVENTION

[0011] (First Embodiment) An event detection system 100 including an event detection unit 20 as an event detection device according to the first embodiment of this disclosure will be described as follows with reference to the drawings.

[0012] As shown in FIGS. 1 and 2, the event detection system 100 includes a plurality of information recording devices 10 installed in each of a plurality of vehicles 1, a server device 30, and an administrator terminal 40. The event detection unit 20 is provided in each information recording device 10. In the first embodiment, a control unit 18 (to be described later) of the information recording device 10 functions as the event detection unit 20.

[0013] In the event detection system 100 of the present embodiment, the event detection unit 20 provided in the information recording device 10 detects a predetermined event based on acceleration and transmits event information regarding the detected event to the server device 30. The server device 30 displays on the terminal side display unit 41 of the administrator terminal 40 that an event has occurred based on the received event information.

[0014] A predetermined event is, for example, an accident or an event that does not result in an accident but has a high probability of an accident occurring, and is an event to be detected by an event detection device. Event information is information acquired and recorded by the information recording device 10 when an accident or an event that does not result in an accident but has a high probability of an accident occurring occurs. An event is detected when the impact applied to the information recording device 10 exceeds a predetermined value, or more specifically, when the change in acceleration acquired by the G sensor 12 provided in the information recording device 10 exceeds an event detection threshold value.

[0015] At this time, actually, an impact caused by a change in the unevenness of the road surface rather than an event such as an accident may be detected as an event. Specifically, when the following events occur, the acceleration may change suddenly, and an event may be determined to have occurred. These events are false detections that are neither accidents nor events that do not result in accidents but have a high probability of an accident occurring. · Impact when the vehicle crosses a curb · Impact when the vehicle travels on a bumpy road surface · Impact when the user of the vehicle closes the door · Impact when the vehicle travels over a road joint · Impact when the vehicle travels over a manhole installed on the road

[0016] If an event detection device can accurately detect the unevenness of the road surface using advanced image recognition technology and detailed road information data, detecting such an event as an event is suppressed, and a true event such as an accident can be detected with higher accuracy. However, using advanced image recognition technology and detailed road information data has the problem that the event detection device becomes expensive. The event detection unit 20 of the present embodiment enables simple and highly accurate determination of whether the detected event is a predetermined event to be detected by the event detection device or not a predetermined event to be detected by the event detection device. In other words, the event detection unit 20 of the present embodiment can more accurately and simply determine whether the detected event is a true event caused by an accident or the like, or not a true event caused by a change in the unevenness of the road surface or the like.

[0017] The information recording device 10 is installed in the vehicle 1 and acquires and records various information including images around the vehicle 1. The information recording device 10 can be a "video recording type drive recorder". As shown in FIG. 2, the information recording device 10 mainly includes a camera unit 11, a G sensor 12, a GPS 13, a communication unit 14, a memory 15, a display unit 16, a speaker 17, a control unit 18, etc. In addition to this, the information recording device 10 includes a microphone that collects the sound inside the vehicle, and an operation unit including a touch panel and buttons operated by the driver or the like.

[0018] The camera unit 11 can capture images around the vehicle 1. For example, the camera unit 11 is composed of a 360-degree camera and can capture 360-degree omnidirectional images around the vehicle. The G sensor 12, also called an acceleration sensor, is a sensor that detects the acceleration, which is the strength of the impact applied to the information recording device 10. Acceleration is also called a G value. The G sensor 12 of the present embodiment is a sensor that detects acceleration in three degrees of freedom, and detects the acceleration in the X-axis direction, which is the front-rear direction with respect to the information recording device 10, the acceleration in the Y-axis direction, which is the left-right direction, and the acceleration in the Z-axis direction, which is the up-down direction.

[0019] GPS 13 is a sensor that acquires the position information of vehicle 1. The communication unit 14 includes a communication module or communication interface and a router, etc., and is connected to a communication network L1 such as a mobile phone communication network to communicate with the server device 30. The memory 15 is composed of a RAM, a ROM, and a non-volatile memory such as an SD card, etc. The memory 15 temporarily or non-temporarily stores the image acquired by the camera unit 11, the acceleration acquired by the G-sensor 12, the position information acquired by GPS 13, the event information detected by the event detection unit 20, etc. The memory 15 temporarily or non-temporarily stores a control program for operating the information recording device 10, application programs such as an event detection program, various threshold values used by the control unit 18, various data and parameters used during various operations, etc. The display unit 16 is composed of a liquid crystal display, etc., and displays the image taken by the camera unit 11, the event information detected by the event detection unit 20, etc. The speaker 17 outputs sounds, messages, etc.

[0020] The control unit 18 is configured to include a processor such as a CPU. The control unit 18 is connected to the camera unit 11, the G-sensor 12, GPS 13, the communication unit 14, the memory 15, the display unit 16, etc., controls the operations of these components, and controls the overall operation of the information recording device 10. The control unit 18 functions as the event detection unit 20 by executing the event detection program stored in the memory 15. The event detection unit 20 includes an acceleration acquisition unit 21, a detection unit 22, a speed acquisition unit 23, an event type determination unit 24, a determination unit 25, and an event notification unit 26.

[0021] The acceleration acquisition unit 21 acquires the acceleration of the vehicle 1 from the G-sensor 12. The detection unit 22 detects an event based on the acceleration acquired by the acceleration acquisition unit 21. When the acceleration exceeds the event detection threshold, the detection unit 22 recognizes that an event has occurred, which has a high possibility of an accident although the accident has not occurred yet, and detects the event. The event detection threshold is a threshold for determining whether to detect an event based on the acceleration acquired by the detection unit 22. The event detection threshold is determined in advance and recorded in the memory 15. The detection unit 22 records the event information related to the detected event in the memory 15. The event information includes the occurrence time of the event, the acceleration during a predetermined period detected by the G-sensor 12, the position information acquired by the GPS 4, the captured image which is the moving image captured by the camera unit 11, the speed of the vehicle 1 acquired by the speed acquisition unit 23 during the period from a predetermined time before the occurrence of the event to a predetermined time after the occurrence of the event, and various information acquired by each part of the information recording device 10 before and after the event occurrence time.

[0022] The speed acquisition unit 23 acquires the speed, which is the value obtained by dividing the distance that the vehicle 1 has moved from one position to another position by the time taken for the movement, and is the distance moved per unit time. The speed acquisition unit 23 of the present embodiment acquires the position information from the GPS 13 and calculates the speed based on the moving distance from one position to another position and the time taken to move from one position to another position. The calculation procedure of the speed is not limited to this. As another different embodiment, the speed acquisition unit 23 is connected to a vehicle speed sensor (not shown) attached to the wheel 2 of the vehicle 1, and can acquire the speed from this vehicle speed sensor. In this case, the vehicle speed sensor detects the speed of the wheel 2 as a pulsed signal. The speed acquisition unit 23 can calculate the vehicle 1 speed by performing a predetermined calculation on the number of pulses of the pulsed signal output from the vehicle speed sensor. As a further different embodiment, the speed acquisition unit 23 can also calculate the speed based on the rotational speed of a drive source such as an engine or a motor. It is desirable to calculate the speed every predetermined time, for example, every 100 msec, but it is not limited to this.

[0023] The event type determination unit 24 determines the type of the event detected by the detection unit 22 based on the value and direction of the acceleration acquired by the acceleration acquisition unit 21. The direction of the acceleration includes the X direction corresponding to the front-rear direction of the information recording device 10, the Y direction corresponding to the left-right direction, and the Z direction corresponding to the up-down direction. The event type determination unit 24 records the determined event type in the memory 15 in association with the event information. Examples of the event type include, but are not limited to, sudden acceleration, sudden deceleration, and sudden steering. When the acceleration acquired by the acceleration acquisition unit 21 exceeds the event detection threshold value and significantly changes in the positive X-axis direction, the event type determination unit 24 determines that the event type is sudden acceleration. Sudden acceleration means that the speed of the vehicle 1 rapidly increases. When the acceleration acquired by the acceleration acquisition unit 21 exceeds the event detection threshold value and significantly changes in the negative X-axis direction, the event type determination unit 24 determines that the event type is sudden deceleration. Sudden deceleration means that the speed of the vehicle 1 rapidly decreases. When the speed acquired by the acceleration acquisition unit 21 exceeds the event detection threshold value and significantly changes in the positive Y-axis direction or the negative Y-axis direction, the event type determination unit 24 determines that the event type is sudden steering. Sudden steering is also called sharp turning and means that the traveling direction of the vehicle 1 rapidly changes to the left or right direction. The event type determination unit 24 determines the event type according to the changes in the acceleration in the X-axis direction and the Y-axis direction, but it can also be determined according to the changes in the acceleration in the Z-axis direction.

[0024] Note that as another different embodiment, the detection unit 22 may also have the function of the event type determination unit, and the detection unit 22 may be configured to detect the occurrence and type of an event based on the accelerations in the X-axis direction, the Y-axis direction, and the Z-axis direction.

[0025] Based on the difference between the average value of the speed in the period before the event and the average value of the speed in the period after the event, the determination unit 25 determines whether the event detected based on the acceleration by the detection unit 22 is a true event. A true event means that the event detected based on the acceleration by the detection unit 22 is a predetermined event that should be detected by the event detection device. Not being a true event means that the event detected based on the acceleration by the detection unit 22 is not a predetermined event that should be detected by the event detection device, but is a false detection caused by, for example, a change in the unevenness of the road surface. Hereinafter, the "average value of the speed in the period before the event" may be referred to as the "average value of the past speed", and the "average value of the speed in the period after the event" may be referred to as the "post-event average value".

[0026] The determination procedure by the determination unit 25 will be described as follows with reference to FIG. 3. FIG. 3 is a diagram for explaining the determination procedure executed by the determination unit 25. In FIG. 3, a graph showing the acceleration in the X-axis direction (front-rear direction) acquired by the acceleration acquisition unit 21 and the speed acquired by the speed acquisition unit 23 is shown. The horizontal axis of this graph is the time t (seconds), the left vertical axis is the acceleration (mG), and the right vertical axis is the speed (km / h). In FIG. 3, the × mark indicates the speed at the event occurrence time, the white circle indicates the average value V1 of the past speed, and the black circle indicates the average value V2 of the post-event speed. In FIG. 3, the event occurrence time, which is the time when the event is detected by the detection unit 22, is t1. The period before the event is the period before the event occurrence time t1, and includes t1 - 1 and t1 - 2 in FIG. 3. The period after the event is the period after the event occurrence time t1, and includes t1 + 1 and t1 + 2 in FIG. 3.

[0027] The determination unit 25 obtains, as the average value of the speed in the period before the event, the average value obtained by averaging the speeds detected by the speed acquisition unit 23 in the period before the event occurrence time. For example, the period before the event occurrence time is the past one second. For example, the average value of the speed in the period before the event is the average value V1 obtained by averaging the speeds detected by the speed acquisition unit 23 in the period from the time t1 - 1, which is one second before the event occurrence time t1, to the time t1 - 2, which is two seconds before the event occurrence time t1. The determination unit 25 obtains, as the average value of the speed in the period after the event, the average value obtained by averaging the speeds acquired by the speed acquisition unit 23 in the period after the event occurrence time. For example, the period after the event occurrence time is the subsequent one second. For example, the average value of the speed in the period after the event is the average value V2 obtained by averaging the speeds detected by the speed acquisition unit 23 in the period from the time t1 + 1, which is one second after the event occurrence time t1, to the time t1 + 2, which is two seconds after the event occurrence time t1.

[0028] When an event is detected, the determination unit 25 calculates the average value of the speed, which is the value obtained by averaging the speeds acquired by the speed acquisition unit 23 over a predetermined period, using the speeds acquired by the speed acquisition unit 23 and recorded in the memory 15, but is not limited thereto. For example, when the predetermined period is the period before the event, the determination unit 25 calculates the average value V1 of the speed, and when the predetermined period is the period after the event, the determination unit 25 calculates the average value V2 of the speed. As another different embodiment, the speed acquisition unit 23 may sequentially calculate the average value of the speed for each predetermined period and record it in the memory 15, and the determination unit 25 may obtain the average values V1 and V2 of the speed before and after the event occurrence time from among the average values of the speed recorded in the memory 15.

[0029] Next, the determination unit 25 calculates the absolute value of the difference ΔV (ΔV = |V1 - V2|), which is the value obtained by subtracting the average value V2 of the speed in the period after the event from the average value V1 of the speed in the period before the event. When the absolute value of this difference ΔV is less than the threshold value of the absolute value of the difference determined in advance, the determination unit 25 determines that the detected event is not due to an accident or the like but is due to a change in the unevenness of the road surface or the like, and determines that the event is not a true event. On the other hand, when the absolute value of this difference ΔV is greater than or equal to the threshold value of the absolute value of the difference, the determination unit 25 determines that the detected event is due to an event that has a high possibility of causing an accident although it does not lead to an accident or the occurrence of an accident, and determines that the event is a true event.

[0030] Further, the determination unit 25 can be configured to perform determination using different determination procedures as follows according to the type of event determined by the event type determination unit 24. When the type of event is sudden acceleration or sudden deceleration, the determination unit 25 determines whether the event is a true event based on the absolute value of the difference ΔV between the average value V1 of the speed in the period before the event and the average value V2 of the speed in the period after the event. That is, when the absolute value of the difference ΔV is less than the threshold value of the absolute value of the difference (for example, 5 km / h), the determination unit 25 determines that the detected sudden acceleration or sudden deceleration is not a true event, and when the absolute value of the difference is greater than or equal to the threshold value of the absolute value of the difference, the determination unit 25 determines that the sudden acceleration or sudden deceleration is a true event.

[0031] When the type of event is sudden steering, the determination unit 25 determines whether the event is a true event based on the average value V1 of the speed in the period before the event. When the average value V1 of the speed in the period before the event is less than the threshold value of the average value of the speed (for example, 10 km / h), the determination unit 25 determines that the sudden steering is not a true event, and when the average value of the speed is greater than or equal to the threshold value of the average value of the speed, the determination unit 25 determines that the sudden steering is a true event.

[0032] The threshold value of the absolute value difference and the threshold value of the average speed, which are event determination threshold values used to determine whether an event is a true event, can be appropriate values according to the vehicle type of vehicle 1, the mounting position of the information recording device 10 on vehicle 1, the business form, and the like. This is because the correspondence relationship between the acceleration detected by the G-sensor 12 and the speed is different due to these differences. Examples of vehicle types include commercial vehicles such as trucks, taxis, buses, and company cars, and personal vehicles owned by individuals. Examples of mounting positions include the upper part of the windshield and the back of the rearview mirror. Examples of business forms include garbage collection, transportation, and shipping. The event determination threshold value can be determined according to the user who uses the event detection system 100 and recorded in the memory 15 in advance, or can be recorded in the memory 15 in an updatable manner. Note that the event determination threshold value is a threshold value used to determine whether an event is a true event, and is different from the event detection threshold value used to detect an event based on acceleration.

[0033] The event notification unit 26 notifies a driver or the server device 30 of a predetermined event. The event notification unit 26 notifies the driver or the server device 30 of an event determined to be a true event by the determination unit 25, and does not notify the driver or the server device 30 of an event determined not to be a true event by the determination unit 25. When notifying the driver, the event notification unit 26 can output a sound indicating that an event has occurred, or a message such as "Sudden acceleration detected.", "Sudden deceleration detected.", "Sudden steering detected." from the speaker 17. The event notification unit 26 can also display, on the display unit 16, an image related to the event in which the location, time, type of the event, and the like are indicated. For example, the event notification unit 26 displays, on the display unit 16, an image related to an event determined to be a true event by the determination unit 25, and does not display, on the display unit 16, an image related to an event determined not to be a true event by the determination unit 25.

[0034] When notifying the server device 30, the event notification unit 26 transmits event information to the server device 30 through the communication unit 14 and the communication network L1. At this time, it is desirable that the event notification unit 26 transmits only the event information of the events determined by the determination unit 25 to be true events among the events detected by the detection unit 22 to the server device 30.

[0035] Note that the event information transmitted by the event notification unit 26 to the server device 30 is not limited to that of true events. As another different embodiment, the event notification unit 26 may be configured to transmit the event information of all the events detected by the detection unit 22 to the server device 30. In this case, the determination unit 25 adds a flag indicating whether the event is a true event to the event information. The determination unit 25 turns on the flag of the true event and turns off the flag of the event that is not a true event. The server device 30 can easily recognize whether the event is a true event by referring to this flag.

[0036] The server device 30 is composed of a cloud server or the like. The administrator terminal 40 is composed of a personal computer, but can be a mobile terminal such as a smartphone or a tablet terminal.

[0037] The server device 30 can communicate with a plurality of information recording devices 10 through the communication network L1 and collect event information from each information recording device 10. The server device 30 communicates with the administrator terminal 40 through a communication network line L2 such as the Internet and displays an image related to the event on the terminal-side display unit 41 of the administrator terminal 40. For example, as shown in FIG. 1, the server device 30 displays a map image showing the driving history of the vehicle 1 and an image related to the event, such as the location, time, and type of the event, superimposed on this map image, on the terminal-side display unit 41. At this time, the server device 30 can notify the administrator of the event with high accuracy by displaying the image related to the event determined to be a true event and not displaying the image related to the event determined not to be a true event.

[0038] In this embodiment, since the event notification unit 26 transmits only the event information of the true event, the server device 30 displays images related to all received events. On the other hand, when the event notification unit 26 transmits the event information of all events in another different embodiment, the server device 30 displays only the images related to the events for which the flag is on.

[0039] An example of the operation flow of the event detection system 100 according to the first embodiment configured as described above will be described as follows with reference to the flowchart of FIG. 4. FIG. 4 shows an example of the operation flow of the information recording device 10, but the operation of the information recording device 10 is not limited to the operations shown in this flowchart.

[0040] In step S0, the information recording device 10 is activated by turning on the power, and becomes capable of acquiring various information and communicating with the server device 30. In the next step S1, the camera unit 11 of the information recording device 10 starts recording an image around the vehicle 1. The image acquired by the camera unit 11 is recorded in the memory 15 by the control unit 18. Also, the G-sensor 12 starts detecting acceleration, and the GPS 13 starts acquiring position information, etc., and each part of the information recording device 10 starts the information acquisition operation. The acquired information is recorded in the memory 15 by the control unit 18 as needed.

[0041] In the next step S2, in order to acquire the speed of the vehicle 1, the speed acquisition unit 23 acquires position information from the GPS 13 and calculates the speed of the vehicle 1 based on the acquired position information. In the next step S3, the acceleration acquisition unit 21 acquires the acceleration of the vehicle 1 in the X-axis direction, Y-axis direction, and Z-axis direction from the G-sensor 12.

[0042] In the next step S4, the detection unit 22 determines whether any of the acquired accelerations in the X-axis direction and the Y-axis direction exceeds the event detection threshold of the acceleration in the X-axis direction or the event detection threshold of the acceleration in the Y-axis direction. When the detection unit 22 determines that any of the above accelerations exceeds the event detection threshold (Yes), it is considered that an event has been detected, and the program proceeds to step S7. When the detection unit 22 determines that any of the above accelerations is below the event detection threshold (No), since no event has occurred, the program proceeds to step S5.

[0043] In step S5, the control unit 18 checks whether it has received an end signal from the power supply circuit of the information recording device 10 and determines whether to continue the event detection process. The end signal is output from the power supply circuit to the control unit 18 when a power-off operation is performed by a driver or the like.

[0044] When the control unit 18 determines not to receive the end signal and to continue the event detection process (Yes), it returns the program to step S2 and executes the processes after step S2 to detect the next event. On the other hand, when the control unit 18 determines to receive the end signal and to end the event detection process (No), the program proceeds to step S6.

[0045] In the next step S6, the control unit 18 ends the event detection process. Note that the event detection process is not limited to ending when a power-off operation is performed, and it can also end when a driver or the like performs an operation to end the event detection process from the operation unit.

[0046] In steps S7 to S11, it is determined whether the event detected in step S4 is a true event. First, in step S7, the event type determination unit 24 determines whether the acceleration in the X-axis direction exceeds the event detection threshold in order to determine the type of the event.

[0047] When the event type determination unit 24 determines that the acceleration in the X-axis direction exceeds the event detection threshold (Yes), it assumes that the event type is a rapid acceleration or deceleration, and advances the program to step S8. When the event type determination unit 24 determines that the acceleration in the X-axis direction does not exceed the event detection threshold (No), since the acceleration in the Y-axis direction exceeds the event detection threshold, it assumes that the event type is a sharp steering, and advances the program to step S11.

[0048] Steps S8 to S10 are executed when it is determined that the event is a rapid acceleration or deceleration. In step S8, the determination unit 25 acquires the speed during the period before the event from the past speeds recorded in the memory 15 in the procedure as described above, and calculates the average value V1 of the past speeds. In the next step S9, the determination unit 25 acquires the speed during the period after the event, and calculates the average value V2 of the subsequent speeds. In the next step S10, the determination unit 25 calculates the absolute value ΔV of the difference between the average value V1 and the average value V2. Thereafter, the control unit 18 advances the program to step S12.

[0049] Step S11 is executed when it is determined that the event is a sharp steering. The determination unit 25 acquires the speed during the period before the event from the past speeds recorded in the memory 15, and calculates the average value V1 of the past speeds. Thereafter, the control unit 18 advances the program to step S12.

[0050] In step S12, the determination unit 25 determines whether the event is a true event based on the absolute value of the difference ΔV calculated in step S10 or the average value V1 of the past speeds calculated in step S11. When the type of the event is sudden acceleration or sudden deceleration, the determination unit 25 compares the absolute value of the difference ΔV calculated in step S10 with the threshold value of the absolute value of the difference. If the absolute value of the difference ΔV is greater than or equal to the threshold value of the absolute value of the difference, the determination unit 25 determines that the event is a true event (Yes) and advances the program to step S13. If the absolute value of the difference ΔV is less than the threshold value of the absolute value of the difference, the determination unit 25 determines that the event is not a true event (No) and advances the program to step S5. When the program advances to step S5, the program advances to step S2 according to the determination in step S5 and the next event detection process is executed, or the program advances to step S6 and the event detection process ends.

[0051] On the other hand, when the type of the event is sudden steering, the determination unit 25 compares the average value V1 of the past speeds calculated in step S11 with the threshold value of the average value of the speeds. If the average value V1 is greater than or equal to the threshold value of the average value of the speeds, the determination unit 25 determines that the event is a true event (Yes) and advances the program to step S13. If the average value V1 is less than the threshold value of the average value of the speeds, the determination unit 25 determines that the event is not a true event (No) and advances the program to step S5. When the program advances to step S5, the program advances to step S2 according to the determination in step S5 and the next event detection process is executed, or the program advances to step S6 and the event detection process ends.

[0052] Step S13 is executed when it is determined that the detected event is a true event. The event notification unit 26 notifies the driver that an event has occurred by outputting a sound or a message from the speaker 17 or displaying an image related to the event on the display unit 16. The event notification unit 26 transmits the event information of the true event to the server device 30 through the communication unit 14 and the communication network L1. The server device 30 can classify, record, and manage the received event information, and display an image related to the event on the terminal-side display unit 41 of the administrator terminal 40 to notify the administrator. The program proceeds to step S5, and according to the determination in step S5, the program proceeds to step S2 to execute the next event detection process, or the program proceeds to step S6 to end the event detection process.

[0053] This concludes the description of the operations performed by the event detection system 100 according to the first embodiment. Note that each of the processes in steps S8 to S13 is executed every time an event is detected in step S4, but can also be executed for all events after all events have been detected and before the end of the event detection process. Also, the transmission of event information to the server device 30 is not limited to being executed every time an event is detected, and can also be executed before the end of the event detection process or when a request is received from the server device 30.

[0054] (Second Embodiment) The event detection system 100A according to the second embodiment shown in FIG. 5 has the same basic configuration as the event detection system 100 according to the first embodiment shown in FIGS. 1 and 2, etc., except that the functions of the event detection device are distributed to the information recording device 10 and the server device 30. Therefore, hereinafter, the description of the same configuration as the first embodiment will be omitted, and the configuration different from the first embodiment will be mainly described.

[0055] As shown in FIG. 5, the event detection system 100A of the second embodiment mainly includes a plurality of information recording devices 10, a server device 30, and an administrator terminal 40. In the second embodiment, the control unit 18 of the information recording device 10 functions as the event detection unit 20A, and the server-side control unit 34 (to be described later) of the server device 30 functions as the server-side event detection unit 50. The event detection unit 20A and the server-side event detection unit 50 constitute the event detection device of the second embodiment.

[0056] Details of each part of the second embodiment will be described as follows with reference to FIG. 5. The information recording device 10 mainly includes a camera unit 11, a G-sensor 12, a GPS 13, a communication unit 14, a memory 15, a display unit 16, a control unit 18, etc., similar to the first embodiment. The camera unit 11, the G-sensor 12, the GPS 13, the communication unit 14, the memory 15, the display unit 16, and the control unit 18 basically have the same configuration and the same functions as those in the first embodiment.

[0057] The control unit 18 includes the aforementioned event detection unit 20A. The event detection unit 20A includes an acceleration acquisition unit 21, a detection unit 22, a speed acquisition unit 23, and an event notification unit 26. Since the functions of the acceleration acquisition unit 21, the detection unit 22, the speed acquisition unit 23, and the event type determination unit 24 are the same as those in the first embodiment, the description thereof will be omitted.

[0058] The event notification unit 26 transmits the event information of the event detected by the detection unit 22 to the server device 30 through the communication unit 14 and the communication network L1. Note that the event notification unit 26 can also display an image related to the event on the display unit 16 or output a sound or a message from the speaker 17.

[0059] The server device 30 mainly includes a server-side communication unit 31, a storage unit 32, an event information database 33, and a server-side control unit 34.

[0060] The server-side communication unit 31 includes a communication module or communication interface and a router or the like. The server-side communication unit 31 can communicate with the information recording device 10 through a communication network L1 such as a mobile phone communication network, and can communicate with the administrator terminal 40 through a communication network line L2 such as the Internet.

[0061] The storage unit 32 is composed of a RAM, a ROM, a hard disk, and the like. The storage unit 32 temporarily or non-temporarily stores a control program for operating the server device 30, application programs such as an event detection program, various threshold values used by the server-side control unit 34, various data and parameters used in various operations, etc. The event information database 33 stores the event information acquired from the information recording device 10.

[0062] The server-side control unit 34 is composed of a processor such as a CPU. The server-side control unit 34 is connected to the server-side communication unit 31 and controls its operation. The server-side control unit 34 accesses the storage unit 32 and the event information database 33 to acquire and store information.

[0063] The server-side control unit 34 functions as a server-side event detection unit 50 by executing the event detection program stored in the storage unit 32. The server-side event detection unit 50 includes an event information acquisition unit 51, an event type determination unit 52, a determination unit 53, a display control unit 54, and an event recording unit 55.

[0064] The event information acquisition unit 51 acquires event information from the information recording device 10 through the server-side communication unit 31 and the communication network L1. The event type determination unit 52 determines the type of event according to the changes in the acceleration in the X-axis direction and the Y-axis direction included in the event information, similar to the aforementioned event type determination unit 24.

[0065] Similar to the aforementioned determination unit 25, when the type of the event is sudden acceleration or sudden deceleration, the determination unit 53 determines whether the event is a true event based on the absolute value ΔV of the difference between the average value V1 of the speed in the period before the event included in the event information and the average value V2 of the speed in the period after the event. When the type of the event is sudden steering, the determination unit 53 determines whether the event is a true event based on the average value V1 of the speed in the period before the event included in the event information.

[0066] The display control unit 54 notifies a predetermined event to the administrator terminal 40 through the server-side communication unit 31 and the communication network line L2. The display control unit 54 notifies a predetermined event determined to be a true event by the determination unit 53 and does not notify an event determined not to be a true event by the determination unit 53. The display control unit 54 transmits an image related to a predetermined event to the administrator terminal 40 and causes it to be displayed on the terminal-side display unit 41. At this time, the display control unit 54 displays an image related to an event determined to be a true event by the determination unit 53 on the terminal-side display unit 41 and does not display an image related to an event determined not to be a true event. By visually recognizing the image displayed on the terminal-side display unit 41, the administrator can recognize that an event has occurred. Therefore, the display control unit 54 functions as an event notification unit that notifies the administrator that an event has been detected.

[0067] The event recording unit 55 stores the event information of an event determined to be a true event in the event information database 33. Or, as another different embodiment, the event recording unit 55 can also store the event information of all events including true events in the event information database 33. At this time, the event recording unit 55 turns on the flag of the event information of the true event and turns off the flag of the event information that is not a true event for the purpose of discriminating whether the event information is that of a true event, and then stores it.

[0068] The administrator terminal 40 is composed of a personal computer, but it can be a mobile terminal such as a smartphone or a tablet terminal. The administrator terminal 40 mainly includes a terminal-side display unit 41, a terminal-side communication unit 42, an operation unit 43, a terminal-side speaker 44, and a terminal-side control unit 45. The administrator terminal 40 also includes devices such as a storage unit and a microphone that a computer has.

[0069] The terminal-side display unit 41 is composed of a touch panel type liquid crystal display or the like, and an image related to an event is displayed under the control of the display control unit 54. The terminal-side communication unit 42 includes a communication module or a communication interface and a router or the like. The terminal-side communication unit 42 can communicate with the server device 30 through the communication network line L2.

[0070] The operation unit 43 is a device operated by the administrator and is composed of a touch panel, a keyboard, a mouse, or the like. The terminal-side speaker 44 outputs sounds and messages under the control of the display control unit 54. The terminal-side control unit 45 is composed of a processor such as a CPU and controls the operation of the entire administrator terminal 40. The terminal-side control unit 45 uses a general-purpose browser or the like, or starts an event detection program installed in advance, accesses the server device 30 through the communication network line L2, and uses the event detection service.

[0071] An example of the operation flow of the event detection system 100A according to the second embodiment having the above configuration is described as follows with reference to the sequence diagram of FIG. 6. FIG. 6 shows an example of the operation flow of the information recording device 10 and the server device 30, but these operations are not limited to the operations shown in this sequence diagram. When the operations shown in this sequence diagram are executed, it is assumed that the server device 30 and the administrator terminal 40 are started and can communicate with each other.

[0072] In step S20, the information recording device 10 is activated by turning on the power, and becomes capable of acquiring various information and communicating with the server device 30. In the next step S21, the camera unit 11 of the information recording device 10 starts recording an image around the vehicle 1, and the acquired image is recorded in the memory 15 by the control unit 18. Also, each part of the information recording device 10 such as the G-sensor 12 starts detecting acceleration and the GPS 13 starts acquiring position information. The acquired information is recorded in the memory 15 by the control unit 18 as needed.

[0073] In the next step S22, the speed acquisition unit 23 acquires position information from the GPS 13 and calculates the speed of the vehicle 1 based on the acquired position information. In the next step S23, the acceleration acquisition unit 21 acquires the acceleration of the vehicle 1 in the X-axis direction, Y-axis direction, and Z-axis direction from the G-sensor 12.

[0074] In the next step S24, the detection unit 22 determines whether any of the accelerations in the X-axis direction and the Y-axis direction exceeds the event detection threshold of the acceleration in the X-axis direction or the event detection threshold of the acceleration in the Y-axis direction. When the detection unit 22 determines that any of the above accelerations has exceeded the event detection threshold (Yes), it is considered that an event has been detected, event information is recorded in the memory 15, and the program proceeds to step S25. When the detection unit 22 determines that any of the above accelerations is below the event detection threshold (No), since no event has occurred, the program proceeds to step S26.

[0075] In step S25, the event notification unit 26 transmits the event information of the event detected in step S24 to the server device 30 through the communication unit 14 and the communication network L1. At this time, the event notification unit 26 can also notify the driver that an event has occurred by outputting a sound or a message from the speaker 17 or displaying an image related to the event on the display unit 16.

[0076] In the server device 30 that has received the event information, the processing after step S30 is executed. The details of the processing in the server device 30 will be described later.

[0077] In step S26, the control unit 18 checks whether it has received an end signal from the power supply circuit of the information recording apparatus 10, and determines whether to continue the event detection process.

[0078] When the control unit 18 determines that it has not received the end signal and continues the event detection process (Yes), it returns the program to step S22 and executes the processes after step S22 to detect the next event. When the control unit 18 determines that it has received the end signal and ends the event detection process (No), it advances the program to step S27.

[0079] In the next step S27, the control unit 18 ends the event detection process. Also in the second embodiment, the event detection process is not limited to ending when the power-off operation is performed by the driver or the like, and can also end when the driver or the like performs an operation to end the event detection process from the operation unit.

[0080] The process executed by the server apparatus 30 is described as follows. In step S30, the event information acquisition unit 51 acquires event information from the information recording apparatus 10 through the communication network L1 and the server-side communication unit 31, and records it in the storage unit 32.

[0081] In the next step S31, the event type determination unit 52 determines whether the acceleration in the X-axis direction included in the event information exceeds the event detection threshold value in order to determine the type of the event. When the event type determination unit 35 determines that the acceleration in the X-axis direction exceeds the event detection threshold value (Yes), it advances the program to step S32 on the assumption that the type of the event is sudden acceleration or sudden deceleration. When the event type determination unit 52 determines that the acceleration in the X-axis direction does not exceed the event detection threshold value (No), it advances the program to step S35 on the assumption that the acceleration in the Y-axis direction exceeds the event detection threshold value, that is, the type of the event is sudden steering.

[0082] Steps S32 to S34 are executed when it is determined that the event is a sudden acceleration or a sudden deceleration. In step S32, the determination unit 53 obtains the speed during the period before the event from the past speeds included in the event information in the same procedure as in the first embodiment, and calculates the average value V1 of the past speeds. In the next step S33, the determination unit 53 obtains the speed during the period after the event and calculates the average value V2 of the subsequent speeds. In the next step S34, the determination unit 53 calculates the absolute value ΔV of the difference between the average value V1 and the average value V2. Thereafter, the server-side control unit 34 advances the program to step S36.

[0083] Step S35 is executed when it is determined that the event is a sudden steering. The determination unit 53 obtains the speed during the period before the event from the past speeds included in the event information and calculates the average value V1 of the past speeds. Thereafter, the server-side control unit 34 advances the program to step S36.

[0084] In step S36, the determination unit 53 determines whether the detected event is a true event based on the absolute value ΔV of the difference calculated in step S33 or the average value V1 of the past speeds calculated in step S35. When the type of the event is sudden acceleration or sudden deceleration, the determination unit 53 determines that the event is a true event (Yes) if the absolute value ΔV of the difference is equal to or greater than the threshold value of the absolute value of the difference previously recorded in the storage unit 32, and advances the program to step S37.

[0085] If the absolute value ΔV of the difference is less than the threshold value of the absolute value of the difference, the determination unit 53 determines that the event is not a true event (No) and returns the program to step S30. When the program advances to step S30, the server-side control unit 34 waits until the next event information is transmitted from the information recording device 10. When the next event information is received, the server-side control unit 34 repeats steps S30 to S38.

[0086] On the other hand, when the type of the event is a sharp steering, the determination unit 53 determines that the event is a true event (Yes) if the average value V1 of the past speeds calculated in step S35 is equal to or greater than the threshold value of the average value of the speeds pre-recorded in the storage unit 32, and advances the program to step S37. If the average value V1 is less than the threshold value of the average value of the speeds, the determination unit 53 determines that the event is not a true event (No) and returns the program to step S30. When the program proceeds to step S30, the server-side control unit 34 waits until the next event information is transmitted from the information recording device 10.

[0087] Step S37 is executed when it is determined that the detected event is a true event. The display control unit 54 displays an image related to the event on the terminal-side display unit 41 of the administrator terminal 40 to notify the administrator that the event has been detected. At this time, the display control unit 54 can also control the terminal-side speaker 44 through the terminal-side control unit 45 to output a sound or a message.

[0088] In the next step S38, the event recording unit 55 stores the event information of the true event in the event information database 33. Thereafter, the program returns to step S30, and the server-side control unit 34 waits until the next event information is transmitted from the information recording device 10.

[0089] This concludes the description of the operations performed by the event detection system 100A according to the second embodiment. Note that the above step S25 is executed every time an event is detected, and steps S31 to S38 are executed every time event information is received in step S30, but the present invention is not limited to this. After all events have been detected and before ending the event detection process, step S25 can be executed so that all detected events are transmitted to the server device 30. Thereafter, steps S31 to S38 can also be executed for all the event information received in step S30. Alternatively, step S25 and step S30 can be executed every time an event is detected, and then steps S31 to S38 can be executed for all the event information.

[0090] As described above, the event detection devices (event detection units 20, 20A, and server-side event detection unit 50) according to the above-described embodiments are event detection devices that detect a predetermined event. The acceleration acquisition unit 21 that acquires the acceleration of the vehicle 1, the detection unit 22 that detects an event based on the acceleration, the speed acquisition unit 23 that acquires the speed of the vehicle 1, the average value V1 of the speed in the period before the event, and the average value V2 of the speed in the period after the event, and determination units 25, 53 that determine whether the event detected based on the acceleration is a true event based on the difference therebetween.

[0091] With this configuration, the event detection devices and event detection systems 100, 100A including the event detection devices according to the above-described embodiments can more accurately and simply determine whether an event detected based on the acceleration of the vehicle 1 is a true event. As a result, it is possible to suppress an impact caused by a change in the unevenness of the road surface or the like from being detected as an event.

[0092] The event detection units 20, server-side event detection unit 50, and event detection systems 100, 100A of the above-described embodiments include event type determination units 24, 52 that determine the type of an event based on the direction of the acceleration acquired by the acceleration acquisition unit 21. The determination units 25, 53 determine whether the event is a true event based on the difference (absolute value ΔV of the difference) between the average value V1 of the speed in the period before the event and the average value V2 of the speed in the period after the event when the type of the event is rapid acceleration or rapid deceleration. The determination units 25, 53 determine whether the event is a true event based on the average value V1 of the speed in the period before the event when the type of the event is rapid steering. With this configuration, the event detection units 20, server-side event detection unit 50, and event detection systems 100, 100A can more accurately and simply determine whether an event detected based on the acceleration of the vehicle 1 is a true event.

[0093] The server - side event detection unit 50 and the event detection system 100A of the second embodiment described above include a display control unit 54 as an event notification unit for notifying a predetermined event. The display control unit 54 notifies an event determined to be a true event and does not notify an event determined not to be a true event. Therefore, since the server - side event detection unit 50 and the event detection system 100A notify a user such as an administrator of a true event and do not notify an event that is not a true event, the notification accuracy of the event is improved.

[0094] In the determination units 25, 53 of the above - described embodiments, when the difference ΔV between the average value V1 of the speed in the period before the event and the average value V2 of the speed in the period after the event is less than the event determination threshold, the detected event is determined not to be a true event. Further, in the determination units 25, 53 of the above - described embodiments, when the difference ΔV between the average value V1 of the speed in the period before the event and the average value V2 of the speed in the period after the event is equal to or greater than the event determination threshold, the detected event is determined to be a true event. Therefore, the determination units 25, 53 can determine whether an event is a true event with higher accuracy and more simply.

[0095] The event detection method executed in the above - described embodiments is an event detection method executed in an event detection system 100, 100A including an information recording device 10 installed in the vehicle 1 and a server device 30. This event detection method is executed by a control unit (the control unit 18 of the information recording device 10 and / or the server - side control unit 34 of the server device 30).

[0096] This event detection method includes an acceleration acquisition step in which a control unit (control unit 18, server-side control unit 34) acquires the acceleration of vehicle 1, a detection step in which an event is detected based on the acceleration, a speed acquisition step in which the speed of vehicle 1 is acquired, and a determination step in which it is determined whether the event detected based on the acceleration is a true event based on the difference between the average value of the speed in the period before the event and the average value of the speed in the period after the event. Therefore, the event detection method executed in each embodiment can determine whether an event is a true event with higher accuracy and more simply.

[0097] As described above, the embodiments of the present disclosure have been described in detail with reference to the drawings. However, the specific configuration is not limited to these embodiments, and design changes that do not deviate from the gist of the present disclosure are included in the present disclosure.

Description of Reference Numerals

[0098] 1: Vehicle 10: Information recording device 18: Control unit 20, 20A: Event detection unit (event detection device) 21: Acceleration acquisition unit 22: Detection unit 23: Speed acquisition unit 24: Event type determination unit 25: Determination unit 30: Server device 34: Server-side control unit (control unit) 35: Event type determination unit 45: Terminal-side control unit 50: Server-side event detection unit (event detection device) 52: Event type determination unit 53: Determination unit 54: Display control unit 100, 100A: Event detection system V1: Average value V2: Average value ΔV: Absolute value of difference

Claims

1. An event detection device for detecting a predetermined event, comprising: an acceleration acquisition unit that acquires the acceleration of a vehicle; a detection unit that detects an event based on the acceleration; a speed acquisition unit that acquires the speed of the vehicle; a determination unit that determines whether the event detected based on the acceleration is a true event based on the difference between the average value of the speed in the period before the event and the average value of the speed in the period after the event; An event detection device comprising the above.

2. An event type determination unit that determines the type of the event based on the direction of the acceleration acquired by the acceleration acquisition unit, wherein the determination unit determines whether the event is a true event based on the difference between the average value of the speed in the period before the event and the average value of the speed in the period after the event when the type of the event is sudden acceleration and sudden deceleration, and determines whether the event is a true event based on the average value of the speed in the period before the event when the type of the event is sudden steering. The event detection device according to claim 1, characterized in that.

3. An event notification unit that notifies the predetermined event, wherein the event notification unit notifies the event determined to be the true event and does not notify the event determined not to be the true event. The event detection device according to claim 1, characterized in that.

4. The determination unit determines that the detected event is not a true event when the difference between the average value of the speed in the period before the event and the average value of the speed in the period after the event is less than a threshold value. The event detection device according to claim 1, characterized in that.

5. The determination unit determines that the detected event is a true event when the difference between the average value of the speed in the period before the event and the average value of the speed in the period after the event is greater than or equal to a threshold value. The event detection device according to claim 1, characterized in that.

6. An event detection method executed in an event detection system including an information recording device installed in a vehicle and a server device, comprising: an acceleration acquisition step of acquiring the acceleration of the vehicle; a detection step of detecting an event based on the acceleration; a speed acquisition step of acquiring the speed of the vehicle; A determination step of determining whether the event detected based on the acceleration is a true event based on a difference between an average value of speeds in a period before the event and an average value of speeds in a period after the event; An event detection method characterized by including the above.

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