JP2021163198A - Preparation action determination device, driving assistance system, and program - Google Patents

Abstract

To provide a preparation action determination device and a program capable of determining the presence or absence of a preparation action which is performed by a driver just before a driving operation.SOLUTION: A preparation action determination comprises: a detection unit for detecting an active body motion of a driver who drives a vehicle; and a determination unit for determining whether or not the detected active body motion is a preparation action which is performed before driving operation on the basis of characteristics of preparation actions of the driver stored in a storage unit, which stores preparation actions which are performed before a driving operation as preparation for performing a driving operation for each occupant.SELECTED DRAWING: Figure 15

Description

The present invention relates to a preparatory behavior determination device, a driving support system, and a program.

Conventionally, various safety systems have been introduced into vehicles to avoid danger. In situations such as when there is a risk of collision with the preceding vehicle or when the vehicle deviates from the lane, the driver's condition is detected, and if the driver is unlikely to take risk avoidance action, the system intervenes on the vehicle side. Performs danger avoidance operations such as activating the automatic brake.

In the above-mentioned safety system, a technique for reliably determining the driver's condition is important. Patent Document 1 discloses a technique for determining that the degree of concentration of a driver has increased due to a deviation between the face orientation and the line of sight. Further, Patent Document 2 discloses a technique for discriminating a vague state or the like from the number of saccades.

It is also known that the position of the center of gravity of the driver moves when the driver changes his / her posture. In the technique described in Patent Document 3, using this knowledge, the position of the center of gravity of the driver is calculated from a plurality of load sensors provided on the seat, and the presence or absence of safety confirmation of the driver is determined from the change in the position of the center of gravity. There is.

JP-A-2017-10418 Japanese Unexamined Patent Publication No. 2017-199212 JP-A-2018-2060337

The technique described in Patent Document 1 has a problem that the degree of concentration cannot be appropriately determined in a situation where decentralized attention is required to deal with a danger generated according to a driving environment required for driving.

Since the technique described in Patent Document 2 requires an amount of data that is statistically significant, there are problems that it takes a long time for determination and it is not possible to respond to a sudden change in the state of the driver.

An object of the present invention is to provide a preparatory action determination device and a program capable of accurately determining the presence or absence of a preparatory action performed by a driver immediately before a driving operation.

Another object of the present invention is that the driver can more accurately determine whether or not to take the danger avoidance action by himself / herself as compared with the case based on the estimated value of the degree of drowsiness or the degree of decrease in concentration, and can surely perform the danger avoidance action. , To provide a driving support system.

The preparatory behavior determination device according to one aspect of the present invention has a detection unit that detects the active body movement of the driver who drives the vehicle, and the characteristics of the preparatory behavior that is performed before the driving operation in preparation for the driving operation for each occupant. Based on the characteristics of the driver's preparatory behavior stored in the storage unit stored in, a determination unit for determining whether or not the detected active body movement is a preparatory behavior performed before the driving operation is provided. ing.

The preparatory behavior determination device according to another aspect of the present invention has a calculation unit that detects danger from the environmental information around the vehicle detected by the environment detection unit and calculates the grace time until the danger occurs, and drives the vehicle. The characteristics of the driver's preparatory behavior stored in the detection unit that detects the driver's active body movement and the storage unit that stores the characteristics of the preparatory behavior performed before the driving operation for each occupant in preparation for the driving operation. Based on the above, a determination unit that determines whether or not the detected active body movement is a preparatory action performed before the driving operation, and an active preparatory action before the grace time becomes less than or equal to a predetermined time. It is equipped with an output unit that outputs the result that there is no preparatory action when the target body movement is not detected.

The driving support system of the present invention includes the preparatory action determination device according to claim 6, and a safety device that implements safety measures that perform an action of avoiding danger by vehicle control according to the result of no preparatory action. I have.

In the program of the present invention, the computer is a detection unit that detects the active body movement of the driver who drives the vehicle, and a storage unit that stores the characteristics of the preparatory behavior performed before the driving operation in preparation for the driving operation for each occupant. It is a program for functioning as a determination unit for determining whether or not the detected active body movement is a preparatory behavior performed before a driving operation based on the characteristics of the preparatory behavior of the driver stored in. ..

According to the preparatory action determination device and the program of the present invention, it is possible to accurately determine the presence or absence of the preparatory action performed by the driver immediately before the driving operation.

Further, according to the driving support system of the present invention, it is possible to more accurately determine whether or not the driver himself / herself takes a risk avoidance action as compared with the case based on the estimated value of drowsiness and the degree of decrease in concentration, and the vehicle side can avoid the danger. The operation can be performed reliably and at an early stage.

It is a schematic diagram for explaining a preparatory action. It is a block diagram which shows an example of the electric structure of a driving support system. It is a figure which shows an example of the sensor arrangement of a seat vibration detection. It is a block diagram which shows an example of the functional structure of the preparatory action determination device. It is a schematic diagram of a spring-mass-mass point system. It is a Bode diagram from vehicle acceleration to seat vibration. It is a graph which shows an example of active body movement. It is a figure which shows an example of active body movement by a preparatory action. It is a figure which shows an example of the preparatory behavior pattern. It is a flowchart which shows an example of the flow of the preparatory action determination program. It is a flowchart which shows an example of the flow of the preparatory action memory processing. It is a schematic diagram for demonstrating the time zone of a preparatory action and TTC. This is an example of a table that stores the range of TTC. Another example of a table that stores a range of TTCs. It is a flowchart which shows an example of the flow of the preparatory action determination process. It is a flowchart which shows an example of the processing flow of a safety measure program.

Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.

<Driving support system>
The driving support system according to the embodiment of the present invention detects in real time the preparatory actions taken by the driver before the driving operation while the vehicle is being driven by the driver. Then, when the driver does not take the preparatory action in a dangerous situation, it is determined that the driver does not take the action of avoiding the danger, and the vehicle side performs the danger avoidance action.

(Preparatory action)
First, the preparatory action will be described.
FIG. 1 is a schematic diagram for explaining the preparatory behavior. As shown in FIG. 1, the traveling state of the vehicle includes a steady traveling in which the vehicle travels in a straight line at a constant speed and a normal traveling in which the vehicle is not a steady traveling. A driver who is driving a vehicle in steady driving performs a driving operation such as stepping on a brake or turning the steering wheel to shift the running state of the vehicle from steady running to normal running. That is, the normal running is a running state accompanied by a driving operation.

The driver unconsciously shifts his / her weight in preparation for driving, for example, by tilting his / her body slightly to the right when turning the steering wheel to the left. Active body movements that accompany this weight shift are called "preparatory behaviors." The driver who detects the danger avoids the danger by performing a driving operation before the danger occurs. Since the driver performs a preparatory action before the driving operation, it is possible to accurately determine whether or not the driver performs the driving operation based on the presence or absence of the preparatory action.

(Configuration of driving support system)
Next, the electrical configuration of the driving support system will be described.
FIG. 2 is a block diagram showing an example of the electrical configuration of the driving support system. As shown in FIG. 2, the driving support system 100 has a preparatory action determination device 10 that determines the presence or absence of a preparatory action when a dangerous situation is detected, and a safety measure based on the determination result acquired from the preparatory action determination device 10. It is provided with a safety device 50 for performing the above. The safety device 50 implements safety measures such as automatic braking by vehicle control. The preparatory action determination device 10 and the safety device 50 are communicably connected by wire or wirelessly.

The preparatory action determination device 10 includes an information processing unit 12, an operation information detection unit 18, a seat vibration detection unit 20, a vehicle vibration detection unit 22, an environment detection unit 24, a storage unit 26, and a communication unit 28. The information processing unit 12 acquires information detected by each of the operation information detection unit 18, the seat vibration detection unit 20, the vehicle vibration detection unit 22, and the environment detection unit 24. Further, the information processing unit 12 controls each of the storage unit 26 and the communication unit 28.

The information processing unit 12 is composed of a computer, and includes a CPU (Central Processing Unit) 14 and a memory 16. The memory 16 is composed of a ROM (Read Only Memory), a RAM (Random Access Memory), a non-volatile memory, and the like. The CPU 14 and the memory 16 are connected to each other by a bus.

The operation information detection unit 18 is composed of a group of sensors that detect operation information related to the driving operation by the driver. Examples of the sensor that detects the operation information include a vehicle speed sensor that detects the vehicle speed, a yaw rate sensor that detects the angular velocity of the vehicle in the turning direction, and a steering angle sensor that detects the steering angle of the steering wheel.

The seat vibration detection unit 20 is composed of a plurality of seat vibration sensors that detect the vibration of the seat. As the seat vibration sensor, for example, an acceleration sensor can be used. To give a specific example, an acceleration sensor such as a piezoelectric film sensor using a polyvinylidene chloride (PVDF) film is used as a sheet vibration sensor. Each of the plurality of seat vibration sensors is provided at a position where the driver's body movement can be detected, for example, on the surface or inside of the driver's seat.

FIG. 3 is a diagram showing an example of the arrangement of the seat vibration sensor. As shown in FIG. 3, a plurality of seat vibration sensors (hereinafter, referred to as “sensors A to D”) are provided inside the seat 70. In the illustrated example, the sensor A is on the right side of the backrest 72, which is the backrest, the sensor B is on the left side of the backrest 72, the sensor C is on the right side of the cushion 74, which is the seating part, and the sensor D is on the left side of the cushion 74. , Each is provided.

The vehicle vibration detection unit 22 is composed of a vehicle vibration sensor that detects the vibration of the vehicle. Vehicle vibration is a vibration component derived from vehicle body vibration such as engine vibration and road surface vibration. As the vehicle vibration sensor, for example, an acceleration sensor can be used. The vehicle vibration sensor is provided at a position where a vibration component derived from the vehicle body vibration can be detected, for example, near a seat attachment point in the vehicle body.

The environment detection unit 24 is composed of a group of sensors that detect environmental information representing the environment around the vehicle. The sensor group that detects environmental information includes an in-vehicle camera and a radar.

An HDD (Hard Disk Drive) or the like is used as the storage unit 26. The storage unit 26 stores a "preparatory action determination program" for determining the presence or absence of a preparatory action. The communication unit 28 is a communication interface for communicating with the outside.

The safety device 50 includes a control unit 52, an alarm device 58, a brake device 60, a steering device 62, a storage unit 64, and a communication unit 66. The control unit 52 controls each unit of the alarm device 58, the brake device 60, the steering device 62, the storage unit 64, and the communication unit 66.

The control unit 52 is composed of a computer, and includes a CPU 54 and a memory 56. These are connected to each other by a bus. The memory 56 is composed of a ROM, a RAM, a non-volatile memory, and the like.

The alarm device 58 is, for example, a speaker or a display installed in the vehicle interior of the own vehicle. The brake device 60 is a braking device that applies a braking force to the wheels in response to a control signal from the control unit 52 even when the brake pedal is not depressed by the driver. The steering device 62 is a steering device that steers the wheels in response to a control signal from the control unit 52 even when the steering operation is not performed by the driver.

An HDD or the like is used for the storage unit 64. The storage unit 64 stores a "safety measure program" for implementing safety measures. The communication unit 66 is a communication interface for communicating with the outside.

(Preparatory behavior judgment device)
Next, the functional configuration of the preparatory behavior determination device will be described.
FIG. 4 is a block diagram showing an example of the functional configuration of the preparatory behavior determination device. The information processing unit 12 of the preparatory behavior determination device 10 includes a running state determination unit 30, a transmission function calculation unit 32, a transmission function storage unit 34, a passive body movement calculation unit 36, an active body movement calculation unit 38, and a preparatory behavior storage unit. 40, a danger prediction unit 42, a preparatory action determination unit 44, and a determination result output unit 46 are provided.

The CPU 14 of the information processing unit 12 reads the "preparatory action determination program" stored in the storage unit 26 and executes the program using the memory 16 as a work area, so that the computer functions as each functional unit of the information processing unit 12. (See FIG. 2).

The magnitude of each of the seat vibration, the vehicle vibration, the passive body movement, and the active body movement is the magnitude of the acceleration representing them.

-Collecting and storing preparatory behavior information-
In preparation for the preparatory behavior determination, the preparatory behavior determination device collects the preparatory behavior information during the driving of the driver and performs the preparatory behavior storage process for storing the obtained preparatory behavior pattern peculiar to the driver. The preparatory behavior pattern is an example of "characteristics of preparatory behavior". First, each functional part related to this preparatory behavior memory processing will be described.

The traveling state determination unit 30 determines whether the traveling state is steady traveling or normal traveling from the operation information acquired from the operation information detecting unit 18. For example, when the fluctuations of the steering angle and the accelerator opening fall within a predetermined range, it is determined that the traveling state is steady traveling. When the running state is not steady running, it is determined that the running state is normal running.

The transfer function calculation unit 32 calculates the transfer function from the seat vibration acquired from the seat vibration detection unit 20 and the vehicle vibration acquired from the vehicle vibration detection unit 22 while the traveling state is steady traveling. The transfer function calculation unit 32 stores the transfer function calculated by the transfer function calculation unit 32 in the transfer function storage unit 34.

In order to calculate the transfer function from vehicle vibration to seat vibration, the relationship between the vehicle body, the seat installed in the vehicle, and the occupants on the seat is approximated by the spring-mass-mass point system shown in FIG. The seat vibration is estimated from the vehicle vibration by the transfer function of the second order.

Specifically, among the seat vibrations, the vibration component derived from the vehicle vibration such as the road surface vibration can be estimated from the output of the acceleration sensor attached to the seat attachment point or the like based on the following equation (1).

The transfer function of the above equation (1) is a transfer function using the Laplace transform, and s is the Laplace operator. Also, a ₁ is the acceleration, a ₂ representing the sheet vibrations are acceleration indicative of vehicle vibration at the seat attachment point. m is the mass of the driver seated in the seat.

Further, the above equation (1) shows a transmission function of the seat acceleration from the vehicle acceleration when the driver on the seat shown in FIG. 5 is approximated by the spring-mass-mass point system, and the rigidity of the seat is spring-loaded. It is represented by a constant k, and the viscosity of the sheet is represented by a damping constant c.

The driver's body movements include passive body movements that occur when the body is shaken by vehicle vibration and active body movements that the driver himself moves, and these are mixed. The driver's body movement obtained in steady driving can be regarded as passive body movement.

The passive body movement calculation unit 36 calculates the driver's passive body movement from the vehicle vibration acquired from the vehicle vibration detection unit 22 by using the transfer function stored in the transfer function storage unit 34. Specifically, the passive body motion calculation unit 36 estimates the seat vibration from the vehicle vibration acquired during steady running by using the stored transfer function. Then, the passive body motion calculation unit 36 uses the estimated seat vibration as the driver's passive body motion. FIG. 6 is a Bode diagram from vehicle acceleration to seat vibration. As shown in FIG. 6, it has been experimentally confirmed that the passive body movement (model, broken line) estimated in steady running is in good agreement with the actually detected seat vibration (experimental result, solid line).

The active body movement calculation unit 38 calculates the active body movement by subtracting the passive body movement calculated by the passive body movement calculation unit 36 from the seat vibration acquired from the seat vibration detection unit 20. During steady driving, the driver's active body movement is small, and the detected seat vibration and the estimated passive body movement are approximately equal. On the other hand, when the driver tries to perform a driving operation from steady driving, he / she performs a preparatory action accompanied by a weight shift immediately before the driving operation, so that the active body movement becomes large.

The active body movement calculation unit 38 immediately before the driving operation when it is determined from the operation information that the driving state has changed from the steady driving to the normal driving, that is, when the driver starts the steering operation or the accelerator operation. The active body movement performed in the above is detected and stored in the preparation action storage unit 40 as the detected active body movement preparation action. The active body movement calculation unit 38 accumulates information on the preparatory actions performed during the driver's driving in the preparatory action storage unit 40 one after another. In this way, the preparatory behavior pattern peculiar to the driver is acquired.

-Judgment of preparatory behavior-
The preparatory behavior determination device detects active body movements in real time during steady driving, and the calculated active body movements correspond to the preparatory behaviors based on the driver's unique preparatory behavior pattern stored in advance. Performs preparatory action determination processing to determine whether or not. Next, each functional unit related to this preparatory action determination process will be described. In addition, the functions to be fulfilled are added to the functional parts already described.

The transfer function calculation unit 32 calculates the transfer function from the seat vibration and the vehicle vibration while the traveling state is steady traveling. The passive body movement calculation unit 36 calculates the driver's passive body movement from the vehicle vibration using the transfer function. The active body movement calculation unit 38 calculates the active body movement by subtracting the passive body movement from the seat vibration. In this way, while the vehicle is running, the active body movement is repeatedly calculated from the seat vibration and the vehicle vibration.

The danger prediction unit 42 detects a danger such as a rear-end collision with a preceding vehicle or a deviation from the traveling lane from the environmental information around the vehicle detected by the environment detection unit 24, and takes a preparatory action for the time when the danger is expected to occur. Calculate the time zone expected to occur (hereinafter referred to as "preparatory action time zone") and the like. The active body movement calculation unit 38 detects the active body movement performed during the time zone of the preparatory action determined by the risk prediction unit 42.

The preparatory behavior determination unit 44 refers to the preparatory behavior pattern stored in the preparatory behavior storage unit 40, and determines whether or not the active body movement detected by the active body movement calculation unit 38 corresponds to the preparatory behavior. do. The determination result output unit 46 outputs the determination result by the preparatory action determination unit 44 to the safety device 50.

When it is determined that the detected active body movement corresponds to the preparatory action, the determination result output unit 46 outputs the determination result that "there is a preparatory action". On the other hand, when it is determined that the detected active body movement does not correspond to the preparatory action, the determination result output unit 46 outputs the determination result of "no preparatory action".

When the determination result that "there is a preparatory action" is obtained, the safety device 50 determines that the driving operation by the driver is performed and does not operate. On the other hand, when the determination result of "no preparatory action" is obtained, the safety device 50 determines that the driving operation by the driver is not performed, and implements safety measures such as automatic braking by vehicle control and lane keeping. do. As a safety measure, the safety device 50 may present information such as an alarm that warns of system intervention.

-Preparatory behavior pattern-
Here, the preparatory behavior pattern will be described.
The graph shown in FIG. 7 shows the magnitude of active body movement immediately before steady running and left turn for each of the sensors A to D shown in FIG. As described above, the sensor A is provided on the right side of the backrest, the sensor B is provided on the left side of the backrest, the sensor C is provided on the right side of the cushion, and the sensor D is provided on the left side of the cushion. In the following, the positions corresponding to each of the sensors A to D are represented by A to D.

FIG. 8 is a diagram showing an example of active body movement corresponding to the preparatory behavior. FIG. 8 shows the active activity of the sensors A to D shown in FIG. 7 with respect to the two-dimensional space representing the position in the seat with the horizontal axis in the left-right direction of the seat and the vertical axis in the backrest-cushion direction of the seat. The following values are two-dimensionally plotted using the acceleration data A to D representing the target body movement.
Horizontal axis: (Data A + Data C)-(Data B + Data D)
Vertical axis: (Data A + Data B)-(Data C + Data D)

According to FIGS. 7 and 8, it can be seen at which position on the seat the active body movement is remarkable. The movement of the plot points in FIG. 8 represents the movement of the position of the center of gravity of the driver.

In steady running, as shown in FIG. 8, plot points (◆) representing active body movements are distributed within the range 104 of steady running surrounded by a broken line. On the other hand, immediately before turning left, the active body movements of the left side of the backrest (B) and the right side of the cushion (C) become large. In particular, since the active body movement on the right side (C) of the cushion becomes remarkable, the plot point shifts away from the steady running range 104 and shifts to the lower right. In this way, when the preparatory action is performed, the plot points (■) representing the active body movements move outside the range 104 of the steady running.

FIG. 9 is a diagram showing an example of a preparatory behavior pattern. The preparatory behavior pattern represents the movement range of the position of the center of gravity of the driver when performing the preparatory behavior for each category of the preparatory behavior. In the preparatory behavior memory processing, points representing active body movements performed during the preparatory behavior time zone are plotted in a two-dimensional space to acquire a preparatory behavior pattern peculiar to the driver.

In the preparatory action for braking, there is a shift of the center of gravity to the left backrest side. The plot points (Δ) when the brake operation preparatory action is performed are distributed within the range 108 of the brake operation preparatory action surrounded by the broken line in the upper left of FIG.

It may be avoided by steering operation. The plot points (◯) when the preparatory action for the right-turning steering operation is performed are distributed within the range 110 of the preparatory action for the right-turning operation surrounded by the broken line at the lower left of FIG. The plot points (□) when the steering operation preparatory action for turning left is performed are distributed within the range 112 of the preparatory action for the left turning operation surrounded by the broken line at the lower right of FIG.

If the plot point representing the detected active body movement moves within the range 108 of the preparatory action for the brake operation, the preparatory action determination unit 44 determines that the preparatory action for the brake operation has occurred. Similarly, if the plot point moves within the range 110 of the preparatory action for the right turn operation, it is determined that the preparatory action for the right turn operation has occurred. Similarly, if the plot point moves within the range 112 of the preparatory action for the left turn operation, it is determined that the preparatory action for the left turn operation has occurred.

On the other hand, when the plot point representing the detected active body movement is not included in any of the ranges 108, 110, and 112 of the preparatory action, it is determined that there is no preparatory action even if there is a large movement of the center of gravity. For example, in the action of picking up the luggage in the passenger seat on the left side of the driver's seat, there is a movement of the center of gravity to the cushion side on the left, but the preparatory action because it is a large movement of the center of gravity exceeding the range of 110 of the preparatory action for the right turn operation. Is not determined.

Further, when the plot point is not included in the range of the preparatory action corresponding to the operation required to avoid the danger predicted by the risk prediction unit 42, the preparatory action determination unit 44 determines that there is no corresponding preparatory action. You may judge. For example, in the case of deviation from the traveling lane, a steering operation is required instead of a braking operation. In this case, if the plot point moves within the range 110 or 112 of the preparatory action, it is determined that there is a preparatory action for the steering operation, but if the plot point moves within the range 108 of the preparatory action, it is determined that there is a preparatory action for the steering operation. Judge that there is no preparatory action.

The range of preparatory actions shown in FIG. 9 is a typical typical example. The preparatory behavior pattern differs for each individual depending on the driving posture and the driving operation style. Further, the preparatory action pattern may be prepared for each road type such as an expressway and a general road, or may be prepared for each weather such as rainy weather and other times. In addition, a preparatory behavior pattern may be created using only the latest data for a predetermined period. The accuracy of judgment can be improved by selecting a preparatory behavior pattern suitable for the surrounding environment and situation.

If the preparatory action is performed but the preparatory action is not determined (not detected), the system intervenes before the driver's operation, and the driver feels uncomfortable, such as feeling that it is an obstacle to driving. It will be. On the other hand, if the preparatory action is determined even though the preparatory action has not been performed (false positive), the risk of collision increases because the system does not intervene.

Whether to reduce undetected or falsely detected can be adjusted by setting the boundary of the range of preparatory actions shown in FIG. As the range of preparatory actions increases, undetected cases decrease but false positives increase. As the range of preparatory actions narrows, undetected increases but false positives decrease.

<Preparatory behavior judgment program>
Next, the preparatory action determination program will be described.
The preparatory action determination program is executed by the CPU 14 of the preparatory action determination device 10 when the driver starts driving or in response to an instruction from the driver. Here, a rear-end collision scene with a preceding vehicle will be described as an example of a dangerous situation.

FIG. 10 is a flowchart showing an example of the processing flow of the preparatory action determination program.
In step S100, the CPU 14 determines whether or not the preparatory behavior pattern corresponding to the driver has been acquired in advance.

If the preparatory action pattern has not been acquired, the process proceeds to step S102. In step S102, the CPU 14 executes the "preparatory action storage process" for creating the preparatory action pattern peculiar to the driver, and ends the program.

On the other hand, if the preparatory action pattern has been acquired in advance, the process proceeds to step S104. In step S104, the CPU 14 executes a "preparatory behavior determination process" for determining whether or not the detected active body movement corresponds to the preparatory behavior based on the preparatory behavior pattern peculiar to the driver, and programs the program. To finish.

(Preparatory behavior memory processing)
Next, the preparatory action memory process executed in step 102 of FIG. 10 will be described.
FIG. 11 is a flowchart showing an example of the flow of the preparatory action memory processing.
First, in step S200, the CPU 14 determines whether or not the traveling state is steady traveling based on the operation information. If the traveling state is steady traveling, the process proceeds to step S202. When the traveling state is normal traveling, the determination is repeated in step S200.

Next, in step S202, the CPU 14 acquires the seat vibration and the vehicle vibration. Next, in step S204, the CPU 14 calculates a transfer function from the seat vibration and the vehicle vibration and stores it in the memory.

Next, in step S206, the CPU 14 acquires the seat vibration and the vehicle vibration again. Next, in step S208, the CPU 14 calculates the passive body movement from the vehicle vibration using the transfer function obtained in step S204. Next, in step S210, the CPU 14 subtracts the passive body movement from the seat vibration to calculate the active body movement and stores it in the memory.

Next, in step S212, the CPU 14 determines based on the operation information whether the running state has changed from the steady running to the normal running. If the vehicle has not shifted to normal running, the process returns to step S206 and the calculation of the active body movement is repeated. If the vehicle shifts to normal driving due to the driving operation, the process proceeds to step S214.

Next, in step S214, the CPU 14 stores the active body movement detected immediately before the driving operation as a preparatory action. Next, in step S216, the CPU 14 obtains the collision grace time (TTC: Time-To-Collision) described below, and stores the obtained TTC in the storage unit as the driver's preparatory action information.

As described above, since a rear-end collision scene with the preceding vehicle is assumed here, TTC is used as a reference for the determination timing. The TTC is a value obtained by dividing the inter-vehicle distance (L) between the own vehicle and the preceding vehicle by the relative speed which is the difference between the speed (Vf) of the own vehicle and the speed (Vp) of the preceding vehicle. That is, it is represented by TTC = L / (Vf-Vp). The TTC is used as an indicator of how many seconds it will take to collide if the current relative velocity is maintained.

The distance between the own vehicle and the preceding vehicle is measured by a radar or the like in the own vehicle. In addition, the technical guidelines established by the Ministry of Land, Infrastructure, Transport and Tourism stipulate that the TTC of a passenger car should be 1.4 seconds or less when the automatic brake that reduces collision damage is activated.

FIG. 12 is a schematic diagram for explaining the time zone of the preparatory action and the TTC. As shown in FIG. 12, when it is determined that the braking operation has been started, the active body movement immediately before (a certain time before) is memorized as a preparatory action.

Specifically, the "preparatory action time zone" is defined as a certain time (for example, 5 seconds before) from the time when the accelerator is released before the brake operation. The active body movements detected during this preparatory action time zone are plotted in the two-dimensional space shown in FIGS. 8 and 9, and the maximum value of the movement of the center of gravity, that is, the point farthest from the origin is the TTC at that time. And remember it as a point that represents the preparatory action.

In this way, by accumulating the preparatory action information before the brake operation, the range of the preparatory action for the brake operation and the range of the TTC are specified. What is important here is that the preparatory action of accelerating with the movement of the center of gravity leads to the action of braking. The time zone for the preparatory action may be set to a fixed time such as 5 seconds, or may be set to a different time zone for each individual by reflecting the detected preparatory action information.

Next, in step S218, the CPU 14 determines whether or not the traveling state is steady traveling based on the operation information. When returning to the steady running, the process returns to step S206. If the vehicle remains in normal driving, the process proceeds to step 220. Next, in step S220, the CPU 14 determines whether or not the operation is completed.

When the operation is finished, the program is finished. If the operation is not completed, the process returns to step S218 to determine whether or not the traveling state is steady traveling. Until the operation is completed, when the steady running is achieved, the process returns to step S206, and the preparatory action, the detection and storage of the TTC are repeated. As a result, the driver's preparatory behavior pattern (see FIG. 9) and the range of TTC for each type of driving operation are acquired. The range of TTC, that is, the time zone of preparatory behavior is an example of "characteristics of preparatory behavior".

13 and 14 are examples of a table showing the range of TTC of driver A. As shown in FIG. 13, the range from the minimum value to the maximum value of the obtained TTC may be stored in the table 200 for each type of operation. As shown in the table 200A shown in FIG. 14, the obtained TTC range can be stored separately for each inter-vehicle time (THW: Time Head Way). Further, the average value of TTC may be stored. Further, in this example, the TTC obtained from the driving operation of the driver is stored, but the range of the TTC may be set on the system side.

THW is obtained by dividing the inter-vehicle distance (L) between the own vehicle and the preceding vehicle by the speed (Vf) of the own vehicle. That is, it is represented by THW == L / Vf. Although there are differences depending on the driving style of the individual, the THW value differs depending on the traffic conditions even for the same driver. In a crowded traffic situation, you may drive in a state where sufficient THW is not secured (THW is small). At that time, the range of TTC in the preparatory action for the brake operation also tends to shift to the shorter side. For example, by setting the TTC range for each THW level such as large, medium, and small, it is possible to provide a system that does not give the driver a sense of discomfort.

(Preparatory action judgment processing)
Next, the preparatory action determination process executed in step 104 of FIG. 10 will be described.
FIG. 15 is a flowchart showing an example of the flow of the preparatory action determination process.
First, in step S300, the CPU 14 determines whether or not the traveling state is steady traveling based on the operation information. If the traveling state is steady traveling, the process proceeds to step S302. When the traveling state is normal traveling, the determination is repeated in step S300.

Next, in step S302, the CPU 14 acquires the seat vibration and the vehicle vibration. Next, in step S304, the CPU 14 calculates a transfer function from the seat vibration and the vehicle vibration and stores it in the memory.

Next, in step S306, the CPU 14 acquires the seat vibration and the vehicle vibration again. Next, in step S308, the CPU 14 calculates the passive body movement from the vehicle vibration using the transfer function obtained in step S304. Next, in step S310, the CPU 14 subtracts the passive body movement from the seat vibration to calculate the active body movement and stores it in the memory.

Next, in step S312, the CPU 14 determines whether or not a danger has been detected from the environmental information around the vehicle. If a danger is detected, the process proceeds to step S314. If no danger is detected, the process returns to step S306 and the calculation of the active voice movement is repeated. Here, the possibility of a rear-end collision with the preceding vehicle, which is an obstacle, is detected.

Next, in step S314, the CPU 14 calculates the TTC, which is the collision grace time. What is calculated here is the current TTC. Further, the range from the minimum value to the maximum value of the TTC stored in advance for the driver is set as the time zone for the preparatory action.

Next, in step S316, the CPU 14 reads the maximum value of the driver's TTC stored in advance (hereinafter, abbreviated as "TTCmax") from the storage unit, and determines whether or not the current TTC is TTCmax or less. .. If the current TTC is TTC max or less, it is assumed that the time zone for the preparatory action has been entered, and the process proceeds to step S318. If the current TTC is larger than the TTC max, the process returns to step S306 and the calculation of the active voice movement is repeated.

Next, in step S318, the CPU 14 determines whether or not the active body movement obtained in step S310 corresponds to the preparatory action necessary for avoiding danger (rear-end collision with the preceding vehicle). If the active body movement does not correspond to the preparatory action, the process proceeds to step S320 with no preparatory action. On the other hand, when the active body movement corresponds to the preparatory action, it is assumed that there is a preparatory action, and the process proceeds to step S328.

As described above, the obtained active body movements are plotted in the two-dimensional space shown in FIGS. 8 and 9, and when the plot points are included in the range 108 of the preparatory action for the braking operation, the obtained active body movements are obtained. It is judged that the body movement corresponds to the preparatory action. On the other hand, when the plot points are not included in the range 108 of the preparatory action, it is determined that the obtained active body movement does not correspond to the preparatory action.

When there is a preparatory action, that is, when the preparatory action is performed during the time zone of the preparatory action, in step S328, the CPU 14 outputs a determination result of "preparatory action" to the safety device and ends the program.

On the other hand, when there is no preparatory action, in the next step S320, the CPU 14 reads the average value of the driver's TTC stored in advance (hereinafter, abbreviated as "TTCave") from the storage unit, and the current TTC is set. Determine if it is less than or equal to TTCave.

If the current TTC is less than or equal to TTCave, the process proceeds to step S322. In step S322, the CPU 14 outputs an alarm output instruction to the safety device, and proceeds to step S324. If the current TTC is larger than the TTCave, the process returns to step S306.

Next, in step S324, the minimum value of the driver's TTC stored in advance (hereinafter, abbreviated as "TTCmin") is read from the storage unit, and it is determined whether or not the current TTC is TTCmin or less. If the current TTC is larger than the TTC min, it is still the time zone for the preparatory action, and the process returns to step S306. On the other hand, when the current TTC is TTC min or less, it is assumed that the preparatory action has not been performed during the preparatory action time zone, and the process proceeds to step S326.

If the preparatory action is not performed during the preparatory action time zone, in step S326, the CPU 14 outputs a determination result of "no preparatory action" to the safety device, and ends the program. In the case of the judgment result of "no preparatory action", the judgment result is output to the safety device together with the type of driving operation required to avoid the danger.

<Safety measures program>
Next, the processing on the safety device side will be described.
FIG. 16 is a flowchart showing an example of the processing flow of the safety measure program.
The CPU 54 of the control unit 52 of the safety device 50 reads out the "safety countermeasure program" stored in the storage unit 64 and executes the program using the memory 56 as a work area (see FIG. 2). The "safety measure program" is executed when the safety device 50 receives the determination result or the alarm output instruction from the preparatory action determination device 10.

First, in step S400, the CPU 41 determines whether or not the received information is a determination result of "no preparatory action". If the determination result is "no preparatory action", the process proceeds to step S402. In the next step S402, it is determined whether or not the required driving operation is the braking operation. If it is a brake operation, the process proceeds to step S404. In step S404, the CPU 54 performs automatic braking control and ends the program.

If it is not a brake operation, it is assumed that the necessary driving operation is a steering operation, and the process proceeds to step S406. In step S406, the CPU 54 performs automatic steering control according to the required driving operation and ends the program.

On the other hand, if the determination result of "no preparatory action" is not obtained in step S400, the process proceeds to step S408. In step S408, the CPU 41 determines whether or not the received information is an alarm output instruction. If it is an alarm output instruction, the process proceeds to step S410. In step S410, the CPU 54 activates the alarm device to end the program. The alarm device alerts the driver, such as sounding an alarm that warns of system intervention.

If the received information is a determination result of "preparatory action", a negative determination is made in step S408. In this case, no safety measures are required, so the program is terminated.

<Modification example>
Although exemplary embodiments of the preparatory behavior determination device, the driving support system, and the program have been described above, the present invention is not limited to the scope described in the embodiments. Various changes or improvements can be made to the embodiments without departing from the gist of the present invention, and the modified or improved forms are also included in the technical scope of the present invention.

For example, the processing flow of the program described in the above embodiment is also an example, and even if unnecessary steps are deleted, new steps are added, or the processing order is changed within a range that does not deviate from the purpose. good.

Further, in the above-described embodiment, the case where the processing according to the embodiment is realized by the software configuration by using the computer by executing the program has been described, but the present invention is not limited to this. For example, the processing may be realized by a hardware configuration or a combination of the hardware configuration and the software configuration.

10 Preparatory action judgment device 12 Information processing unit 14 CPU
16 Memory 18 Operation information detection unit 20 Seat vibration detection unit 22 Vehicle vibration detection unit 24 Environment detection unit 26 Storage unit 28 Communication unit 30 Running state determination unit 32 Transmission function calculation unit 34 Transmission function storage unit 36 Passive body movement calculation unit 38 Active body movement calculation unit 40 Preparatory action storage unit 42 Danger prediction unit 44 Preparatory action judgment unit 46 Judgment result output unit 50 Safety device 52 Control unit 54 CPU
56 Memory 58 Alarm device 60 Brake device 62 Steering device 64 Storage unit 66 Communication unit 70 Seat 72 Backrest 74 Cushion 100 Driving support system 200 Table 200A Table

Claims (8)

A detector that detects the active body movement of the driver who drives the vehicle,
The detected active body movement is driven based on the characteristics of the driver's preparatory behavior stored in the storage unit that stores the characteristics of the preparatory behavior performed before the driving operation as preparation for the driving operation for each occupant. A judgment unit that determines whether or not it is a preparatory action performed before the operation,
Preparatory behavior judgment device equipped with. The detection unit
The vibration of the vehicle detected by the vehicle vibration detection unit and the vibration of the seat detected by the seat vibration detection unit are acquired, and the vibration component due to the driver's passive body movement caused by the vibration of the vehicle is obtained from the vibration of the seat. The remaining vibration component after subtraction is detected as the driver's active body movement,
The preparatory action determination device according to claim 1. The detection unit
The relationship between the vehicle body, the seat installed in the vehicle, and the occupants on the seat is approximated by a spring-mass-mass point system, and the transfer function is obtained from the vibration of the vehicle and the vibration of the seat. Using the obtained transfer function, the driver's passive body movement is estimated from the vibration of the vehicle.
The preparatory action determination device according to claim 1 or 2. The determination unit
When the movement destination of the driver's center of gravity position due to the detected active body movement is within the movement range of the driver's center of gravity position when performing the preparatory action, the detected active body movement is the driving operation. Judge that it is a preparatory action to be taken before,
The preparatory action determination device according to any one of claims 1 to 3. The determination unit
The destination of the driver's center of gravity position due to the detected active body movement is within the movement range of the driver's center of gravity position when performing the preparatory action, and the detected active body movement has occurred. When the time is the time zone in which the preparatory behavior is predicted to occur, it is determined that the detected active body movement is the preparatory behavior performed before the driving operation.
The preparatory action determination device according to any one of claims 1 to 3. A calculation unit that detects danger from the environmental information around the vehicle detected by the environment detection unit and calculates the grace time until the danger occurs.
A detector that detects the active body movement of the driver who drives the vehicle,
The detected active body movement is driven based on the characteristics of the driver's preparatory behavior stored in the storage unit that stores the characteristics of the preparatory behavior performed before the driving operation as preparation for the driving operation for each occupant. A judgment unit that determines whether or not it is a preparatory action performed before the operation,
An output unit that outputs a determination result that there is no preparatory action when active body movement, which is a preparatory action, is not detected before the grace time becomes less than a predetermined time.
Preparatory behavior judgment device equipped with. The preparatory action determination device according to claim 6 and
A safety device that implements safety measures that take actions to avoid danger by controlling the vehicle according to the judgment result that there is no preparatory action.
Driving support system equipped with. Computer,
A detector that detects the active body movements of the driver driving the vehicle,
The detected active body movement is driven based on the characteristics of the driver's preparatory behavior stored in the storage unit that stores the characteristics of the preparatory behavior performed before the driving operation as preparation for the driving operation for each occupant. Judgment unit that determines whether or not it is a preparatory action performed before the operation,
A program to function as.

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