JP2005247271A - Control device of occupant crash protection - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To optimally operate an occupant crash protection device while suppressing a desired operation. <P>SOLUTION: A slip angle β is determined based on an input of each sensor value (steps 130 and 132), a value β<SB>us</SB>for an under-steering state smaller than the reference is determined (step 140) when the travel state is the under-steering state (yes in step 134), and a value βus for an over-steering state smaller than the reference is determined (step 146) when the travel state is the over-steering state (no in step 134). Then, whether or not the present vehicle state is an emergency state, when the under-steering state or the over-steering state is a threshold (¾β¾>=βth) or higher (yes in step 148), an occupant crash protection auxiliary device 12 is operated. Thus, the automobile can vary the threshold with the under-steering state or the over-steering state, and can certainly protect the occupant. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  The present invention relates to an occupant protection control device, and more particularly to an occupant protection control device that controls an occupant protection device such as an airbag device or a pretensioner mounted on an automobile.

  An automobile is often equipped with an auxiliary safety system for protecting passengers, such as an airbag device or a pretensioner. The airbag device deployment control and pretensioner control are performed by detecting acceleration after a collision by using a plurality of acceleration sensors (hereinafter referred to as G sensors) or by using a contact sensor or the like in an emergency. Control is performed by detecting the state. Here, in order to avoid false detections such as acceleration that occurs when overcoming a step or acceleration that is applied to the vehicle body when the door is closed, the conventional occupant protection control system provides an acceleration threshold value that allows these noises. The occupant protection device such as an airbag device is controlled based on the threshold value.

In order to operate such an occupant protection device optimally, collision prediction is performed based on the position of the host vehicle by a navigation system or the like and the state of the host vehicle by a vehicle motion state analysis device or the like, and according to the result of the collision prediction. Thus, a technique for controlling the operation of the occupant protection device has been proposed (see, for example, Patent Document 1). In this technology, collision prediction is performed by a G sensor or the like, a threshold value for starting the operation of the occupant protection device is set according to the result of the collision prediction, and the operation of the occupant protection device is started based on the threshold value. By doing so, the occupant protection device can be operated reliably and appropriately after the collision is detected.
JP 2002-104131 A

  By the way, in recent years, in order to improve safety, that is, avoid an emergency state or damage of a vehicle to a minimum, a technique for operating an occupant protection device at an early stage has been developed. For example, in recent technology, an emergency state of a vehicle such as a collision is predicted, and an occupant protection system that operates an occupant protection device such as an airbag device or a webbing that holds an occupant at an early stage (so-called so-called occupant protection system) Pre-crash safe system) has been put into practical use.

  However, when an emergency state of a vehicle such as a collision is predicted and operated based on a prediction result in order to activate the occupant protection device at an early stage, the conventional occupant protection device reaches the emergency state of the vehicle by setting a threshold value. This includes a large number of vehicles that are not in a traveling state, which increases unnecessary operations of the occupant protection device.

  The present invention has been made in consideration of the above facts, and an object of the present invention is to provide an occupant protection control device capable of operating an occupant protection device and the like optimally.

  To achieve the above object, the occupant protection control device according to the present invention includes a detection unit that detects a vehicle state quantity relating to traveling of the host vehicle, and a vehicle state quantity detected by the detection unit that exceeds a predetermined reference value. A predicting means for predicting that the host vehicle is in a driving state leading to an emergency state, a control means for controlling the operation of the occupant protection device based on a prediction result of the predicting means, and a vehicle state quantity detected by the detecting means Setting means for setting the reference value to a predetermined value on the operating side of the occupant protection device from the reference value when the traveling state of the host vehicle is an understeer state or an oversteer state.

  According to the present invention, the detection means detects the vehicle state quantity related to the traveling of the host vehicle. The vehicle is in a traveling state when traveling by operating or operating various devices. This running state has a vehicle state quantity relating to the running of the host vehicle such as the vehicle speed, the vehicle acceleration in the front-rear direction or the left-right direction, for example. Note that the running state, which is the behavior of the vehicle, can be acquired using a known technique such as VSC (Vehicle Stability Control) or ABS (Anti-lock Brake System). Further, the vehicle state quantity includes a slip angle, a yaw rate, a roll angle, a speed thereof, and the like as related to traveling of the host vehicle. Further, the vehicle state quantity includes a steering angle and a steering angular velocity. In addition, you may further include the operation amount of the acceleration apparatus by a passenger | crew's operation, or a braking device as a vehicle state quantity. These vehicle state quantities may be directly detected by a detector, but may be obtained by calculation from various sensor output values. In the vehicle state quantity, a reference value that is allowable when traveling in a standard manner is determined in advance, and when the reference value is exceeded, the vehicle state amount is often a traveling state that deviates from the standard traveling state. . Therefore, the predicting means predicts that the host vehicle is in a traveling state that reaches an emergency state when the vehicle state quantity exceeds the reference value. As an example of this emergency state, there is a collision state with another vehicle or structure. Based on the prediction result of the prediction means, the control means controls the operation of the occupant protection device. Here, when the running state is an understeer state or an oversteer state, the possibility that the host vehicle reaches an emergency state increases according to the amount. Therefore, the setting means predetermines a reference value on the operating side of the occupant protection device based on the reference value when the traveling state of the host vehicle based on the vehicle state quantity such as a slip angle or a slip angular velocity is an understeer state or an oversteer state. The predetermined value, for example, a predetermined value smaller than the reference value is set. As a result, in the case of an understeer state or an oversteer state, an emergency state is predicted by changing the threshold value and the operation of the occupant protection device is controlled, so that the occupant corresponds to the behavior of the own vehicle, that is, the understeer state or the oversteer state. The protection device can be operated.

  In the occupant protection control device of the present invention, the predetermined value includes a plurality of preset values corresponding to the speed of the host vehicle, the detecting means detects the speed of the host vehicle, and the setting means is the host vehicle. A setting value corresponding to the speed can be set to the predetermined value.

  In the understeer state or the oversteer state, the degree of influence on the behavior of the vehicle increases or decreases according to the speed of the vehicle. For example, even in the same understeer state, the moving distance of the vehicle increases as the vehicle speed increases. Therefore, a plurality of set values are determined in advance as the predetermined values corresponding to the speed of the host vehicle. And a detection means detects the speed of the own vehicle, and a setting means sets the setting value corresponding to the speed of the own vehicle to the said predetermined value. This makes it possible to set a fine set value corresponding to the speed of the vehicle.

  The occupant protection control device according to the present invention further includes image detection means for detecting image information around the own vehicle, and the setting means determines whether the position of the own vehicle is a structure around the road or the vehicle from the detection result of the image detection means. The predetermined value can be further changed to a value on the operating side of the occupant protection device when the vehicle is in a traveling state for traveling in a direction opposite to the vehicle.

  In the case of a traveling state toward a structure such as an oncoming lane or a guard rail as the behavior of the vehicle, there is a high probability that the traveling state reaches an emergency state. Therefore, when the image information around the own vehicle is detected and the vehicle position is in a traveling state for traveling to a structure around the traveling road or a traveling road for traveling in the opposite direction to the own vehicle, the predetermined value is set to the occupant. By further changing the value to the operating side of the protective device, it is possible to set a fine set value corresponding to an emergency state toward a structure such as an oncoming lane or a guardrail.

  In this case, the image detection means may have map information including structure information around the traveling road, detect the position of the host vehicle, and detect structures around the host vehicle. The detection of the position of the host vehicle can be realized by, for example, a known navigation system. Thereby, it is possible to easily detect structures around the vehicle position by matching with map information including structure information around the traveling road.

  Further, the image detection means may detect the boundary of the traveling path along which the host vehicle travels and also detect the position of the host vehicle. In this way, by detecting the boundary of the travel path, it is possible to easily identify the travel path on which the host vehicle travels and the travel path such as the oncoming lane. In addition, when specifying a travel route, accuracy is further improved by using the detection result of the navigation system.

  According to another aspect of the present invention, there is provided an occupant protection control device comprising: a detecting unit that detects a vehicle state quantity relating to traveling of the host vehicle; and the host vehicle is in an emergency state when the vehicle state quantity detected by the detecting unit exceeds a predetermined reference value. A prediction means for predicting that the vehicle is in a traveling state, a control means for controlling the operation of the occupant protection device based on a prediction result of the prediction means, and a traveling state of the host vehicle based on a vehicle state amount detected by the detection means And changing means for setting the reference value to a predetermined value on the operating side of the occupant protection device from the reference value when an understeer state and an oversteer state occur within a predetermined time.

  If the vehicle's running state is unstable, for example, if the vehicle is meandering, understeering or oversteering excessively, the occupant may operate in the opposite direction of the vehicle's behavior or reverse the behavior. The vehicle may indicate. In this case, an understeer state and an oversteer state occur as the traveling state of the host vehicle by the vehicle state quantity. This occurrence has a high probability of being in a traveling state that leads to an emergency state within a predetermined time experimentally or empirically obtained in advance. Therefore, when the understeer state and the oversteer state occur within a predetermined time as the traveling state of the host vehicle, the setting means sets the reference value to a predetermined value on the operating side of the occupant protection device from the reference value. Set. Thereby, even when the vehicle is in an unstable traveling state, the traveling state leading to the emergency state can be reliably predicted.

  The changing means of the occupant protection control device is provided when the vehicle condition quantity corresponding to the understeer state or the oversteer state exceeds the permission condition value within the predetermined time after the predetermined permission condition value is exceeded. When the vehicle state quantity corresponding to the other running state of the understeer state or the oversteer state exceeds a predetermined execution condition value, the reference value is set to a predetermined predetermined value on the operating side of the occupant protection device from the reference value. Can be set to a value.

  In a driving state such as a slalom or a driving state where an obstacle avoidance action is performed, an understeer state and an oversteer state may occur within a predetermined time. However, in the traveling state that leads to the emergency state, the vehicle state amount greatly fluctuates within a predetermined time. Therefore, when the vehicle state quantity corresponding to the understeer state or the oversteer state exceeds a predetermined permission condition value, the time is measured, and when the measured time is within the predetermined time, the vehicle state corresponding to the other running state A predetermined value is set when the amount exceeds a predetermined execution condition value. That is, the allowable condition value is a vehicle state quantity that has a possibility of a traveling state that leads to an emergency state but has a low probability of being a traveling state that leads to an emergency state. When the allowable condition value is exceeded and the execution condition value indicating the reverse traveling state is exceeded within a predetermined time, the probability that the traveling state reaches the emergency state is high. Therefore, for example, the behavior of the host vehicle that is likely to reach the host vehicle in a spin state, a drift-out state, or the like can be predicted in advance.

  As the vehicle state quantity, a fluctuation amount or a fluctuation rate (differential value) per unit time of the vehicle state quantity detected by the detection unit can be adopted.

  The vehicle state quantity changes from moment to moment. Therefore, by adopting a fluctuation amount or a fluctuation rate (for example, a differential value) per unit time, it is possible to set a predetermined value according to the degree of change.

  As described above, according to the present invention, when it is predicted that the vehicle state quantity related to the traveling of the host vehicle exceeds the reference value and the emergency state is reached, the vehicle is in the understeer state or the oversteer state. Since the reference value can be changed, there is an effect that the occupant protection device can be optimally operated by operating the occupant protection device corresponding to the behavior of the vehicle.

  Hereinafter, an example of an embodiment of the present invention will be described in detail with reference to the drawings. The present embodiment is a pre-crash safe system that is provided in an automobile and operates an air bag device or a winding device that winds up a webbing that holds an occupant at an early stage by predicting an emergency state of a vehicle such as a collision. The present invention is applied to an occupant protection system.

  In this embodiment, an air bag device, a webbing take-up device for winding up a so-called seat belt, and a brake assist device are provided in an automobile as devices targeted by the occupant protection system. The description will be made assuming that each device is controlled.

  As shown in FIG. 1, the occupant protection system is provided with a vehicle state prediction device 10. As main components, the vehicle state prediction device 10 includes an airbag ECU 24 that is a component of the airbag device, a webbing winding. A webbing take-up ECU 20 that is a component of the take-off device and a brake assist ECU 16 that is a component of the brake assist device are provided. A brake assist actuator 18 is provided in the vicinity of the brake assist ECU 16. In addition, a webbing take-up actuator 22 that takes up the webbing that is wound around each occupant is provided below each of the driver seat and the passenger seat. Further, a radar sensor 40 that detects a structure in front of the vehicle is provided in the front part of the automobile.

  The airbag device is filled with gas generated by ignition of a chemical substance equipped in the airbag device by a deployment signal output from the airbag ECU 24 in response to an impact detected by the G sensor (FIG. 2). As a result, the bag body is unfolded to reduce the load at the time of collision. The airbag device is installed at least for the driver's seat provided in the center portion of the steering, and can be installed on any of the side surfaces of the passenger seat, the rear seat, the driver seat side, and the passenger seat side. is there.

  The webbing take-up device is configured to take up the webbing by operating the webbing take-up actuator 22 in accordance with an instruction signal indicating the emergency state of the automobile predicted by the vehicle state prediction device 10 as will be described later. Similarly, in the brake assist device, the brake assist actuator 18 is actuated by an instruction signal indicating the emergency state of the vehicle predicted by the vehicle state prediction device 10 described later to control the braking force of the vehicle in advance.

[First Embodiment]
Next, the passenger protection system according to the present embodiment will be further described with reference to FIG.

  As shown in FIG. 2, the occupant protection system according to the present embodiment has a computer configuration having a CPU, a ROM, and a RAM and connected to an input / output port (I / O) so as to be able to exchange commands and data. A vehicle state prediction device 10 for predicting an emergency state such as a car collision and an occupant protection assistance device 12 are provided. The vehicle state prediction device 10 is connected to an external device or sensor via an input / output port (I / O). Further, the vehicle state prediction device 10 is connected to a driving state assist device 27 that analyzes the driving state (for example, slip angle, drift-out, etc.) of the automobile and assists the driving state. In the example of FIG. 2, the driving state assist device 27 includes a VSC / ECU equipped in a VSC (Vehicle Stability Control) and an ABS / ECU equipped in an ABS (Anti-lock Brake System). . In the example of FIG. 2, an airbag ECU 24 to which an acceleration sensor 46 that constitutes an airbag device that functions as an occupant protection device is connected.

  A steering sensor 30 for detecting a steering angle and a yaw rate sensor 32 are connected to the driving state assist device 27. The yaw rate sensor 32 is for detecting the yaw rate generated in the automobile, and the steering sensor 30 is provided in the steering and detects the steering angle of the steering. In addition, a throttle sensor 34, a vehicle speed sensor 36, and a brake operation sensor 38 are connected to the driving state assist device 27. The throttle sensor 34 is provided in the throttle body of the engine and detects the throttle opening. The vehicle speed sensor 36 obtains the speed of the automobile obtained from the wheel speed obtained from the sensor provided on each wheel of the automobile, or detects the speed of the automobile by a sensor provided in the speedometer. The brake operation sensor 38 is provided on the brake pedal and detects a braking force instruction amount. Further, the driving state assist device 27 is provided with a left / right acceleration sensor 31 and a longitudinal acceleration sensor 33 in order to detect acceleration in a traveling direction of the automobile and a direction orthogonal to the traveling direction.

  The vehicle state prediction apparatus 10 is connected to an airbag ECU 24 to which an acceleration sensor 46 is connected. The acceleration sensor 46 is for detecting acceleration caused by traveling of an automobile or acceleration caused by a collision. Further, a plurality of acceleration sensors 46 can be provided to detect the acceleration in the direction of travel of the automobile and the direction orthogonal to the direction of travel, like the lateral acceleration sensor 31 and the longitudinal acceleration sensor 33. The airbag ECU 24 is configured to instruct the deployment of the airbag device when an acceleration greater than a predetermined value applied to the automobile is detected by the acceleration sensor 46. That is, when the output signal from the acceleration sensor 46 (the minimum acceleration gradually increases with a collision, the airbag ECU 24 gradually rises from the middle of rising), the output signal of the acceleration sensor 46 exceeds a predetermined threshold value. In the case, the deployment of the airbag device is instructed. As a result, the airbag device is deployed.

  In the example of FIG. 2, the various sensors for detecting the traveling state of the automobile are connected via the airbag ECU 24 and the driving state assist device 27, but each sensor is directly connected to the vehicle state prediction device 10. You may connect. Moreover, you may provide the movement state analysis apparatus which analyzes the movement state of a motor vehicle based on the information obtained from each above-mentioned sensor. For example, the motion state analysis apparatus includes the yaw rate detected by the yaw rate sensor 32, the steering angle detected by the steering sensor 30, the wheel speeds and vehicle speeds detected by the vehicle speed sensor 36, and the throttle opening detected by the throttle sensor 34. Based on the acceleration in each direction applied to the vehicle detected by the acceleration sensor 46, the motor's motion state such as a spin state, a brake lock state, a drift-out state, and a normal running state is determined or specified.

  In addition, a radar sensor 40, an image sensor 42, and a positioning sensor 44 are connected to the vehicle state prediction apparatus 10. The radar sensor 40 is for detecting a structure in front of the automobile, and the image sensor 42 is for imaging the surrounding environment of the automobile. The positioning sensor 44 is for detecting the position of the automobile with high accuracy. The positioning sensor 44 can be realized by, for example, a known navigation system, and compares the self-position measured by a signal from a satellite with map information stored in a recording medium such as a DVD, or the like. It is possible to detect information around the position (existence and types of structures (types of structures such as utility poles, buildings, wooden houses, guardrails, and materials such as concrete) and the like).

  The sensors connected to the vehicle state prediction device 10 are not limited to the above. For example, a vehicle speed sensor that detects the speed of the automobile, a sensor that detects the shift position of the transmission, and the like are provided in a transmission or the like. May be.

  Here, an occupant protection auxiliary device 12 is connected to the vehicle state prediction device 10. The occupant protection assisting device 12 includes a webbing take-up ECU 20 and a webbing take-up actuator 22 that constitute a webbing take-up device, a brake assist ECU 16 and a brake assist actuator 18 that constitute a brake assist device, and threshold values for deploying an airbag device. The airbag ignition set value changing unit 14 is changed. The webbing take-up device has a function of winding the webbing by a signal from the vehicle state prediction device 10, and the brake assist device has a function of adjusting a braking force by a signal from the vehicle state prediction device 10. . The airbag ignition set value changing unit 14 has a function of changing the threshold value of the output signal of the acceleration sensor 46 for instructing the deployment of the airbag device by a signal from the vehicle state prediction device 10. Note that a suspension assist device that adjusts the damping force of the shock absorber by a signal from the vehicle state prediction device 10 may be added to the passenger protection assisting device 12.

  Note that not all of the above-described sensors and devices connected to the vehicle state prediction device 10 constitute elements of the occupant protection device of the present invention. Although details will be described later, it is sufficient that at least a slip angle or the like can be obtained as a sensor, and the occupant protection assisting device 12 may be any device or another device that assists the state of the automobile.

  Next, the operation of the occupant protection system will be described focusing on the operation of the vehicle state prediction device 10. First, FIG. 3 shows a flow of basic operations of the vehicle state prediction apparatus 10.

  In the vehicle state prediction apparatus 10, the basic routine shown in FIG. 3 is executed every predetermined time. First, sensor value input processing is performed by reading the output signal of each sensor in step 100. Here, signals from the steering sensor 30, the yaw rate sensor 32, the throttle sensor 34, the vehicle speed sensor 36, the brake operation sensor 38, the radar sensor 40, the image sensor 42, the positioning sensor 44, and the acceleration sensor 46 may be input as they are. Each signal may be input via the airbag ECU 24 and the driving state assist device 27. Further, signals generated in the airbag ECU 24 and the driving state assist device 27 may be input.

  In the next step 102, the vehicle state is specified by predicting the traveling state of the automobile from the sensor value. This step 102 is to obtain a predicted value as the vehicle state, and the predicted value is a calculated value representing the running state of the automobile obtained from the output signals of the various sensors detected at step 100. For example, values representing the yaw rate, steering angle, vehicle speed, throttle opening, acceleration, and the like obtained from each sensor are obtained as calculation values. This calculated value includes a case in which a traveling state leading to an emergency state such as a spin state, a brake lock state, a drift-out state, or the like is represented. That is, when the calculated value is within a predetermined threshold (set value), the possibility of reaching an emergency state is low. Further, the arrival distance and the arrival time to the structure around the vehicle can be obtained by the radar sensor 40, the image sensor 42, and the positioning sensor 44, and the possibility of reaching an emergency state such as a collision can be obtained.

  Therefore, in the next step 104, it is determined whether or not the vehicle state is an emergency state. This determination is made by determining whether or not the predicted value obtained in step 102 exceeds a predetermined set value. As described above, the set value is determined experimentally or empirically by the value or calculation value of each sensor.

  In the next step 106, in order to operate the passenger protection assisting device 12, an instruction signal is output. The occupant protection assisting device 12 receives the instruction signal and protects the occupant in at least one of the airbag device by the airbag ignition set value changing unit 14, the brake assist device by the brake assist ECU 16, and the webbing take-up device by the webbing take-up ECU 20. Auxiliary processing is performed. The airbag ignition set value changing unit 14 shortens the deployment timing of the airbag device by reducing the threshold value that defines the deployment of the airbag device by the airbag ECU 24. The brake assist device controls the brake assist actuator 18 by the brake assist ECU 16 to supplementarily increase the braking force. In the webbing take-up device, the webbing take-up ECU 20 controls the webbing take-up actuator 22 to take up the webbing, thereby strengthening the occupant protection power.

  Thereby, when it is predicted that the state of the vehicle will reach an emergency state such as a collision, the occupant protection assisting device 12 can be quickly operated, so that the occupant can be protected.

  By the way, if the determination as to whether or not the emergency state is reached is performed based on a single set value, the frequency of predicting that the emergency state is reached increases even if the behavior of the vehicle is caused by an occupant operation during normal driving. This is because the behavior of the automobile due to the occupant operation varies. Therefore, in order to reliably protect the occupant, it is preferable to change the set value serving as a criterion for determining whether or not the emergency state is reached according to the traveling state. Therefore, in the present embodiment, based on the basic routine described above, an auxiliary condition for changing the set value according to the running state is determined, and a criterion for determining whether or not the emergency state is reached is changed according to the auxiliary condition. Yes.

First auxiliary condition This auxiliary condition leads to an emergency state whether or not the driving state assist device 27, that is, the system of either VSC or ABS is installed in the vehicle, or whether the system is operating or not operating. This is taken into account in the judgment criteria.

  In FIG. 4, the flow of operation | movement of the vehicle state prediction apparatus 10 for implement | achieving this auxiliary condition was shown. First, in step 110, each sensor value is input as in step 100 of FIG. Here, the predetermined value Do is set to the threshold value Dth. In the next step 112, the vehicle state is specified in the same manner as in step 102, and in the next step 114, it is determined whether or not the vehicle is equipped with either VSC or ABS. If the result in Step 114 is negative, the routine proceeds to Step 122, where it is determined whether or not the current vehicle state D is an emergency state (D ≧ Dth) as in Step 104 above. If the determination in step 122 is affirmative, an instruction signal is output in step 124 in the same manner as in step 106 to activate the occupant protection assisting device 12 in order to activate the occupant protection assisting device 12.

  On the other hand, when the determination at step 114 is affirmative, the routine proceeds to step 116, where it is determined whether either VSC or ABS is operating. When the operation is in progress (Yes in step 116), the process proceeds to step 118, where the prescribed value Da (Da <Do) smaller than the predetermined value Do is set as the threshold value Dth. This is because when either VSC or ABS is operating, there is a higher possibility of reaching an emergency state than when not operating. On the other hand, if the result in Step 116 is negative, a specified value Db (Db <Do) smaller than the predetermined value Do is set in Step 120 as the threshold value Dth. In step 116, it is preferable to proceed to step 120 when either VSC or ABS is inoperative due to a failure, and to proceed to step 122 in other cases. This is because when either VSC or ABS is inactive, there is a failure time and a non-operation time due to normal running, and in order to assist the VSC or ABS that should be originally operated in the event of a failure. For this reason, it is preferable to define the specified value to an intermediate value (Da <Db <Do).

  Thereby, since a threshold value can be changed by the operating state of either VSC or ABS, the occupant protection assisting device 12 can be quickly operated, and occupant protection can be reliably performed.

Second auxiliary condition This auxiliary condition is to change the set value (threshold value) when the vehicle is in the understeer state or the oversteer state (driving state). That is, this auxiliary condition takes the understeer state or the oversteer state into consideration for determining whether or not to reach an emergency state.

  FIG. 5 shows an operation flow of the vehicle state prediction apparatus 10 for realizing the auxiliary condition. First, in step 130, each sensor value is input as in step 100 of FIG. Here, the slip angle β is adopted as the vehicle state. In step 130, a predetermined reference value βst is set as the set value βth. In the next step 132, the vehicle state is specified in the same manner as in step 102. Here, it is assumed that the slip angle β is calculated. In the next step 134, it is determined whether or not the driving state of the vehicle is an understeer state. In the understeer state, the yaw is insufficient to move forward with respect to the steering input (steering angle), and the slip angle increases. The determination in step 134 in the present embodiment is made based on the slip angle. The slip angle is an angle formed by the traveling direction of the vehicle and the tire direction (steering angle), and the vehicle is in the traveling direction in the direction opposite to the steering angle indicating direction (rotating direction) and the tire direction. Is understeered. On the other hand, the oversteer state is a case in which the yaw is large and a turn exceeding the steering angle instruction occurs, and the vehicle travels inward from the tire direction according to the steering instruction.

  When the vehicle state is an understeer state (Yes in step 134), in step 140, a predetermined value βth smaller than the reference value βst for the understeer state traveling state is set to a predetermined value βth (βus <βst). On the other hand, if the result is negative in step 134 and the vehicle is in the oversteer state, the process proceeds to step 146, and a predetermined value βth smaller than the reference value βst is set as the predetermined value βth for the running state in the oversteer state (βus <βst). The understeer state value βus and the oversteer state value βos may be the same value or different values.

  In the next step 148, as in step 104 of FIG. 3, it is determined whether or not the current vehicle state is an emergency state, and whether the understeer state or the oversteer state is equal to or greater than a threshold value (| β | ≧ βth). Judgment by. If the determination in step 148 is affirmative, an instruction signal is output in step 150 to activate the occupant protection assisting device 12 in order to activate the occupant protection assisting device 12 as in step 106 described above.

  As a result, the threshold value can be changed depending on whether the vehicle is in an understeer state or an oversteer state, so that the occupant protection assisting device 12 can be operated quickly, and the occupant can be protected reliably.

  In this auxiliary condition, the process of step 130 corresponds to the process of the detection means of the present invention, the determination of step 134 corresponds to the process of the prediction means of the present invention, and the process of step 150 corresponds to the process of the control means of the present invention. It corresponds to processing. Further, the processing of steps 140 and 146 corresponds to the processing of the setting means of the present invention.

Third auxiliary condition This auxiliary condition is to change the set value (threshold value) according to the vehicle speed when the vehicle behavior (running state) is an understeer state or an oversteer state. That is, this auxiliary condition considers the vehicle speed and the understeer state or the oversteer state as criteria for determining whether or not the emergency state is reached.

  FIG. 6 shows an operation flow of the vehicle state prediction apparatus 10 for realizing the auxiliary condition. The difference from the processing routine of FIG. 5 is that the vehicle speed V is taken into consideration for the sensor value to be input in step 130 and that steps 136 and 142 are added. First, at step 130, each sensor value is input. Here, the slip angle β is adopted as the vehicle state, and the vehicle speed V is input. Next, the slip angle β is calculated (step 132), and it is determined whether or not the vehicle is in an understeer state (step 134).

  When the vehicle state is an understeer state (Yes in step 134), the process proceeds to step 136, and a value βus reflecting the vehicle speed V is set. Βus, which is the threshold value for the understeer state, is previously determined experimentally and empirically to have a correspondence with the vehicle speed V. The coefficient that corresponds to this correspondence is represented by a function f (V). As a result, the value βus reflecting the vehicle speed V can be obtained by multiplying the value βus by the function f (V) as a coefficient (βus = βus · f (V)). Next, a value βus reflecting the vehicle speed V is set to a predetermined value βth (step 140).

  On the other hand, when the result in Step 134 is negative and the vehicle is in the oversteer state, the process proceeds to Step 142, where the value βos reflecting the vehicle speed V is set. Βos, which is the threshold value for the oversteer state, is previously determined experimentally and empirically in correspondence with the vehicle speed V. The coefficient that corresponds to this correspondence is represented by a function g (V). Thereby, the value βos reflecting the vehicle speed V can be obtained by multiplying the value βos by the function g (V) as a coefficient (βos = βos · g (V)). Next, a value βos reflecting the vehicle speed V is set to a predetermined value βth (step 146). The functions f and g may be the same function or different functions.

  Note that the functions f and g are not limited to functions having continuous characteristics. For example, it may be a discontinuous characteristic based on a polynomial, or a table representing the correspondence between the coefficient and the vehicle speed V.

  Thereby, since the threshold value can be changed according to the vehicle speed of the vehicle when the vehicle is in either the understeer state or the oversteer state, the occupant protection assisting device 12 can be operated quickly and finely. Crew protection can be ensured.

  In this auxiliary condition, the processing of step 130 corresponds to including the processing of detecting the speed of the host vehicle of the present invention, and the processing of steps 136 and 142 sets the set value corresponding to the vehicle speed in the setting means of the present invention. This corresponds to the processing to be set.

-4th auxiliary | assistant condition This auxiliary | assistant condition changes a setting value (threshold value) according to a motor vehicle periphery environment, when it is an understeer state or an oversteer state as a behavior (driving state) of a motor vehicle. That is, this auxiliary condition considers the environment around the automobile and the understeer state or the oversteer state as criteria for determining whether or not to reach an emergency state.

  In FIG. 7, the flow of operation | movement of the vehicle state prediction apparatus 10 for implement | achieving this auxiliary condition was shown. The difference from the processing routine of FIG. 5 is that a sensor value based on own vehicle recognition is input to the sensor value to be input in step 130 from image information, map information, and the like, and steps 138 and 144 are added. is there. First, at step 130, each sensor value is input. Here, the slip angle β is adopted as the vehicle state, and the sensor value N based on the own vehicle recognition is input from image information such as an image or a map.

  As the sensor value N in this auxiliary condition, the sensor values of the radar sensor 40, the image sensor 42, and the positioning sensor 44 can be used. When the radar sensor 40 is used, the distance to the structure in front of the automobile is input as a sensor value. When the image sensor 42 is used, the vehicle lane is recognized using an image captured around the automobile as an input, and the distance to the oncoming lane or the guard rail is input as a sensor value. In this case, it is preferable to assign the direction as an attribute. Similarly, when the positioning sensor 44 is used, the own lane in which the automobile is traveling is recognized, and the distance to the oncoming lane and the guard rail is input as a sensor value. Note that these sensor values may be combined.

  Next, the slip angle β is calculated (step 132), and it is determined whether or not the vehicle is in an understeer state (step 134). When the vehicle state is an understeer state (Yes in step 134), the process proceeds to step 138, and a value βus reflecting the sensor value N based on the surrounding environment based on the image information is set. Βus, which is the threshold value for the understeer state, is previously determined experimentally and empirically in correspondence with the sensor value N according to the surrounding environment. The coefficient that corresponds to this correspondence is represented by a function h (N). Thus, by multiplying the value βus by the function h (N) as a coefficient, the value βus reflecting the sensor value N according to the surrounding environment can be obtained (βus = βus · h (N)). Next, a value βus reflecting the sensor value N according to the surrounding environment is set to a predetermined value βth (step 140).

  On the other hand, when the result in Step 134 is negative and the state is an oversteer state, the process proceeds to Step 144, where a value βos reflecting the sensor value N according to the surrounding environment is set. Βos, which is the threshold value for the oversteer state, is previously determined experimentally and empirically in correspondence with the sensor value N according to the surrounding environment. A coefficient corresponding to this correspondence is represented by a function j (N). Thus, by multiplying the value βos by the function j (N) as a coefficient, the value βos reflecting the sensor value N according to the surrounding environment can be obtained (βos = βos · j (N)). Next, a value βos reflecting the sensor value N according to the surrounding environment is set to a predetermined value βth (step 146). The functions h and j may be the same function or different functions.

  Note that the functions h and j are not limited to functions having continuous characteristics. For example, it may be a discontinuous characteristic based on a polynomial, or a table representing the correspondence between the coefficient and the vehicle speed V.

  In this auxiliary condition, the process of step 130 corresponds to the process of detecting the image information of the image detecting means of the present invention, and the processes of steps 138 and 144 are the detection of the image detecting means in the setting means of the present invention. This corresponds to a process of changing the setting value according to the result.

  Accordingly, the threshold can be adjusted when the own lane is recognized based on the image information and the slip side is the opposite lane or the guard rail. Therefore, when the vehicle is in an understeer state or an oversteer state, the threshold value can be changed according to the surrounding environment of the vehicle, so that the occupant protection auxiliary device 12 can be operated quickly and finely. Crew protection can be ensured.

  As described above, the system according to the present embodiment can change the threshold according to a predetermined auxiliary condition according to, for example, when the vehicle is in an understeer state or an oversteer state. The occupant protection assisting device 12 can be finely actuated, and the occupant can be reliably protected.

[Second Embodiment]
In the above embodiment, the setting value (threshold value) is changed according to the auxiliary condition, but in this embodiment, the setting value (threshold value) is changed when a plurality of auxiliary conditions are met. In addition, since this Embodiment is the structure similar to the said embodiment, the same code | symbol is attached | subjected to the same part and detailed description is abbreviate | omitted.

  When an understeer state or an oversteer state occurs during the operation of the vehicle, the occupant may give instructions to the vehicle such as steering to avoid this. However, when there is a time difference until an occupant's instruction by steering or the like is reflected in the behavior of the automobile, the instruction is larger or the reflected behavior of the automobile is larger. For example, when an oversteer condition occurs and the car is in an anxiety point state, when steering is performed, that is, when a reverse turn instruction is issued, an oversteer condition occurs at that time Further, when the reverse turning instruction is given or when the understeer state occurs, the turning instruction is further increased, and the unstable state of the automobile may become continuous. Thus, in the present embodiment, auxiliary conditions are defined between the oversteer state and the understeer state in time series, and when a plurality of auxiliary conditions in which the oversteer state and the understeer state occur within a certain time are met. The set value (threshold value) is changed. That is, in the present embodiment, the understeer state and the oversteer state that occur within a certain time are taken into consideration as a criterion for determining whether or not an emergency state is reached.

  FIG. 9 is a characteristic diagram showing the relationship between vehicle operation and behavior. FIG. 9A shows the relationship between the steering angle θ and the yaw rate Yr. In the figure, it is assumed that the occupant instructs a left turn after a right turn. Although the occupant's steering amount is substantially the same for left and right turns, as one of the vehicle states that appear as the behavior of the car, the yaw rate Yr increases greatly after the left turn and may eventually lead to the spin state of the car. is there. This is because when a vehicle operation (steering in the above case) that avoids an oversteer state (understeer state) occurs, a reaction exceeding the amount of operation appears in the vehicle, that is, from an oversteer state to an understeer state. It is considered that the reaction is superimposed on the understeer state.

  Therefore, in the present embodiment, the first condition value (value ± Yr1 in FIG. 9A) for monitoring the unstable state of the automobile is obtained as an experimental or empirical value as the vehicle state quantity. And when it is equal to or greater than the first condition value, monitoring is started assuming that the vehicle is in an unstable state. During this monitoring, the vehicle state (value ± Yr2 in FIG. 9A) that is expected to reach the emergency state of the vehicle is determined experimentally or empirically, and this value exceeds the second condition value. Then, the operation of the passenger protection assisting device 12 is started. Moreover, even if the vehicle state is equal to or higher than the first condition value, it has been found that the probability of shifting to an emergency state is low in a period exceeding a certain period obtained experimentally or empirically. For this reason, the time limit is taken into consideration in the above criteria. In FIG. 9A, the time point when the vehicle state becomes equal to or higher than the first condition value is indicated by “Δ”, and the time point when the vehicle state becomes higher than the second condition value is indicated by “□”.

  Similarly, FIG. 9B shows, as a characteristic diagram, the relationship between the vehicle operation (steering angle θ) and the slip angle β as a behavior in the same state as in FIG. 9A. As can be understood from the figure, the result of the slip angle β appears after the steering. Similarly, when this slip angle β is employed, the first condition value (value ± β1 in FIG. 9B) for monitoring the unstable state of the automobile is experimentally or empirically determined as the vehicle state quantity. The obtained value is determined, and monitoring is started assuming that the automobile is in an unstable state when the value is equal to or greater than the first condition value. During this monitoring, the vehicle state (value ± β2 in FIG. 9B) that is expected to reach the emergency state of the automobile is determined experimentally or empirically, and the value is equal to or greater than the second condition value. Then, the operation of the passenger protection assisting device 12 is started. The same applies to considering the time limit in the above judgment criteria. In FIG. 9B, the time when the vehicle state becomes equal to or higher than the first condition value is indicated by “Δ”, and the time when the vehicle state becomes higher than the second condition value is indicated by “□”.

  FIG. 9C shows the characteristic of the slip angular velocity dβ instead of the slip angle β employed in FIG. 9B. As can be understood from the figure, the result of the slip angular velocity dβ appears with a delay from the steering as in the case of the slip angle β. Similarly, when this slip angular velocity dβ is adopted, the first condition value (value ± dβ1 in FIG. 9C) is determined, and monitoring is started as the vehicle is in an unstable state when the value exceeds the first condition value. To do. During this monitoring, a vehicle state (value ± dβ2 in FIG. 9C) that is expected to reach an emergency state of the vehicle is determined, and when the second condition value is exceeded, the operation of the occupant protection assisting device 12 is started. . The same applies to considering the time limit in the above judgment criteria. In FIG. 9C, the time when the vehicle state becomes equal to or higher than the first condition value is indicated by “Δ”, and the time when the vehicle state becomes higher than the second condition value is indicated by “□”.

  Hereinafter, a specific example of the vehicle state prediction device 10 when the slip angle β is adopted as the vehicle state amount will be described.

  In FIG. 8, the flow of operation | movement of the vehicle state prediction apparatus 10 in this Embodiment was shown. In the present embodiment, the slip angle β is adopted as the vehicle state, the vehicle state that is highly likely to reach the emergency state is set as the first condition, and the boundary value is set to the first condition value βst1, and the emergency state may be reached. As a second condition, a vehicle state having a high value is set as a second condition value βst2 (βst2 ≧ βst1), and a value obtained experimentally or empirically is determined in advance. That is, in the present embodiment, the first condition value βst1 and the second condition value βst2 are provided as the reference value βst. In addition, for a period in which both the first condition and the second condition are satisfied, a predetermined period T1 obtained through experiments and experience is predetermined.

  That is, the first condition, which is an auxiliary condition in the present embodiment, is that the slip angle β in the vehicle state is equal to or greater than the first condition value βst1. The second condition is a vehicle state (oversteer state or understeer state) opposite to the vehicle state (understeer state or oversteer state) when the first condition is satisfied within a certain period T1 after the first condition is satisfied. State) and the slip angle β, which is the vehicle state at that time, is equal to or greater than the second condition value βst2.

  First, at step 200, each sensor value is input. Here, the slip angle β is adopted as the vehicle state. In step 200, the flag F1 indicating whether the first condition is satisfied (value “1”) or not satisfied (value “0”) is read. Since this flag F1 is not established when the occupant protection assisting device 12 is activated, a value “0” is set as an initial value. Further, a predetermined reference value βst is set as an initial value of the set value βth. Note that the set value βth is reset in the course of the supplementary processing, and therefore need not be set in this step. In the next step 202, the vehicle state is specified by calculating the slip angle β and obtaining the value. In the next step 204, it is determined whether or not the first condition is established by referring to the value of the flag F1.

  If negative at step 204, the routine proceeds to step 206, where a first condition value βst1 set in advance is set as the set value βth. In the next step 208, it is determined whether or not the slip angle β obtained in step 202 is equal to or greater than the first condition value βst1. This determination is to determine whether a slip angle equal to or greater than a predetermined first condition value βst1 is a value that establishes the first condition of the vehicle state that has a high possibility of reaching an emergency state and should be monitored. . In other words, by determining whether the understeer state or the oversteer state is equal to or greater than the threshold (| β | ≧ βth), it is highly likely that the current vehicle state is an emergency state and should be monitored. Judgment. When the result in step 208 is negative, the first condition is not satisfied and monitoring is not necessary, so the process proceeds to step 214 and the timer is reset and the process ends. On the other hand, when the result in step 208 is affirmative, since the current slip angle β is a value that satisfies the first condition in step 210, the flag F1 is set to a value (“1”) indicating that the first condition is satisfied. set. In the next step 212, the current slip angle β, that is, the slip angle β when the first condition is satisfied is stored as the temporary slip angle βt. In the next step 214, the timer is reset to enable time measurement after the first condition is satisfied.

  On the other hand, if the result in step 204 is affirmative, since the first condition has already been established, the routine proceeds to step 216, where the timer is counted up (T = T + 1), and in the next step 218, the timer count value T is kept for a certain period. It is determined whether or not it is within T1 (T ≦ T1). If the result in Step 218 is negative, the first condition is satisfied but a certain period of time T1 to be monitored has passed, so that the process proceeds to Step 228 and the flag F1 is set to shift to the normal running state or the initial state. Reset (F1 = 0), reset the provisional slip angle βt in step 230 (βt = 0), and terminate this routine.

  If the timer count value T is within the fixed period T1 (T ≦ T1), the result is affirmative in step 218. Proceed to step 220. In step 220, it is determined whether both an understeer state and an oversteer state have occurred within a predetermined period T1. This determination is made by referring to the sign of the multiplication result of the current slip angle β and the temporary slip angle βt. When it is the same state, it is a plus sign, and when both states occur, it is a minus sign. When the result in step 220 is negative, the routine is terminated as it is, and when the result is affirmative, the process proceeds to step 222. In step 222, a predetermined second condition value βst2 is set as the set value βth.

  In the next step 224, it is determined whether or not the slip angle β obtained in step 202 is equal to or greater than the second condition value βst2. This determination is made to determine whether or not the second condition of the vehicle state in which the slip angle equal to or greater than the second condition value βst2 is likely to reach an emergency state is established. In other words, by determining whether the understeer state or the oversteer state opposite to the vehicle state in which the first condition is satisfied is greater than or equal to the threshold (| β | ≧ βth), the vehicle state is in an emergency state while the first condition is satisfied. It is determined whether or not a state where there is a high probability of reaching is reached. When the result in Step 224 is negative, the vehicle state is unlikely to reach an emergency state, but this routine is terminated as it is to continue monitoring.

  On the other hand, when the result in step 224 is affirmative, an instruction signal is output in step 226 to activate the occupant protection assistance device 12 in order to activate the occupant protection assistance device 12. Thereafter, in order to shift to the normal running state or the initial state, the flag F1 is reset (F1 = 0) in step 228, the temporary slip angle βt is cleared (βt = 0) in the next step 230, and this routine is performed. Exit.

  As a result, when the vehicle continues to be in an unstable state and shifts to an emergency state, for example, it shifts to either the understeer state or the oversteer state, and the vehicle state is reversed within a certain time. Even in the case of transition, it is possible to set a threshold value relating to the vehicle state, measure a certain time, and change to the second set value (second condition value βst2). The occupant protection assisting device 12 can be quickly activated when it is predicted that an emergency state will occur while monitoring the state, and the occupant can be protected reliably.

  As described above, the processing in steps 204 to 230 in the present embodiment corresponds to the processing of the changing means of the present invention.

  In the operation of the vehicle state prediction apparatus 10 (FIG. 8), the slip angle β is employed. However, the present invention is not limited to this, and the slip angular velocity dβ may be employed, and the yaw rate Yr may be employed. good.

  In the above description, the slip angle β, which is the vehicle state quantity, is determined from the sensor value. However, the target slip angle βx determined from the vehicle speed, the steering angle, or the like may be used. In this case, the difference between the slip angle β and the target slip angle βx based on the detected sensor value becomes an actual deviation and appears in the behavior of the automobile. Therefore, the difference in the slip angle β based on the sensor value with respect to the calculated target slip angle βx is adopted as the actual slip angle βr (= βx−β) in the vehicle state quantity. As a result, it is possible to consider both the target value and the actual measurement value by the operation of the occupant.

  Employing this target value is more effective when the yaw rate is used as the vehicle state quantity. That is, the yaw rate can be easily calculated as the target yaw rate Yrx based on the steering angle and the vehicle speed. Therefore, the actual slip angle Y (= Yrx−Tr) is adopted as the difference of the yaw rate Yr based on the sensor value with respect to the calculated target yaw rate Yrx as the vehicle state quantity. As a result, the determination corresponding to the behavior of the vehicle corresponding to the occupant's instruction can be easily performed, and the occupant protection assisting device 12 can be actuated quickly and reliably to ensure the occupant's protection.

It is the schematic of the passenger | crew protection system mounted in the motor vehicle concerning this Embodiment. 1 is a block diagram showing a schematic configuration of an occupant protection system according to an embodiment of the present invention. It is a flowchart which shows the flow of the basic process in a passenger | crew protection auxiliary | assistance apparatus including the judgment process of the emergency state for passenger protection which concerns on 1st Embodiment of this invention. It is a flowchart which shows the flow of the process in the passenger | crew protection assistance apparatus which performs the emergency state judgment process for passenger | crew protection by 1st assistance conditions. It is a flowchart which shows the flow of the process in the passenger protection assistance apparatus which performs the emergency state judgment process for passenger protection by 2nd assistance conditions. It is a flowchart which shows the flow of the process in the passenger protection assistance apparatus which performs the emergency state judgment process for passenger protection by 3rd assistance conditions. It is a flowchart which shows the flow of the process in the passenger protection assistance apparatus which performs the emergency state judgment process for passenger protection by 4th assistance conditions. It is a flowchart which shows the flow of the process in the passenger | crew protection assistance apparatus which concerns on 2nd Embodiment of this invention. FIG. 6 is a characteristic diagram showing a vehicle state in the second embodiment, where (A) shows the relationship between the steering angle and the yaw rate, (B) shows the relationship between the steering angle and the slip angle, and (C) shows the characteristic of the slip angular velocity. FIG.

Explanation of symbols

β ... slip angle 10 ... vehicle state prediction device 12 ... occupant protection auxiliary device 14 ... airbag ignition set value changing unit 16 ... brake assist ECU
18 ... Brake assist actuator 20 ... Webbing take-up ECU
22 ... Webbing take-up actuator 24 ... Airbag ECU
30 ... Steering sensor 32 ... Yaw rate sensor 36 ... Vehicle speed sensor 46 ... Acceleration sensor

Claims (6)

Detecting means for detecting a vehicle state quantity relating to traveling of the host vehicle;
Predicting means for predicting that the vehicle is in an emergency state when the vehicle state quantity detected by the detecting means exceeds a predetermined reference value;
Control means for controlling the operation of the occupant protection device based on the prediction result of the prediction means;
The reference value is set to a predetermined predetermined value on the operating side of the occupant protection device from the reference value when the traveling state of the host vehicle based on the vehicle state amount detected by the detection means is an understeer state or an oversteer state. Setting means;
An occupant protection control device.   The predetermined value includes a plurality of predetermined set values corresponding to the speed of the own vehicle, the detecting means detects the speed of the own vehicle, and the setting means sets the set value corresponding to the speed of the own vehicle. The occupant protection control device according to claim 1, wherein the occupant protection control device is set to a predetermined value.   Image detecting means for detecting image information around the own vehicle is further provided, the setting means for causing the position of the own vehicle to run in a direction opposite to the structure around the traveling path or the own vehicle from the detection result of the image detecting means. 3. The occupant protection control device according to claim 1, wherein the predetermined value is further changed to a value on an operating side of the occupant protection device when the vehicle is in a traveling state toward a traveling path. Detecting means for detecting a vehicle state quantity relating to traveling of the host vehicle;
Predicting means for predicting that the vehicle is in an emergency state when the vehicle state quantity detected by the detecting means exceeds a predetermined reference value;
Control means for controlling the operation of the occupant protection device based on the prediction result of the prediction means;
When an understeer state and an oversteer state occur within a predetermined time as the traveling state of the host vehicle based on the vehicle state amount detected by the detection means, the reference value is determined in advance on the operating side of the occupant protection device from the reference value. Changing means for setting to a predetermined value;
An occupant protection control device.   The changing means includes an understeer state or an oversteer state when the vehicle state quantity corresponding to the understeer state or oversteer state exceeds the permission condition value within the predetermined time after the predetermined permission condition value is exceeded. When the vehicle state quantity corresponding to the other running state of the vehicle exceeds a predetermined execution condition value, the reference value is set to a predetermined value on the operating side of the occupant protection device from the reference value. The occupant protection control device according to claim 4, wherein   The occupant protection control device according to claim 4 or 5, wherein the vehicle state quantity is a fluctuation amount or a fluctuation rate per unit time of the vehicle state quantity detected by the detection means.

Images