JP2004268699A - Vehicle rollover deciding device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a vehicle rollover deciding device B by an inexpensive roll rate sensor with excellent rollover deciding accuracy. <P>SOLUTION: When (a roll angle θt determined by integrating a roll rate ωt detected by the roll rate sensor 1 - an inclined angle θ detected by an inclination sensor 2)≤ a prescribed value A is established at the time of stopping a vehicle in this vehicle rollover deciding device B, a sensor function discriminates the establishment to be within prescribed tolerance to correct a rollover region in a roll rate roll angle map by deviation of (the roll angle θt-the inclined angle θ). The presence or absence of the vehicle rollover is decided based on whether or not both of the roll rate ωt and the roll angle θt belong to the corrected roll over region. The presence of the vehicle rollover is decided, an occupant crash protection device is operated. <P>COPYRIGHT: (C)2004,JPO&NCIPI

Description

[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to a vehicle rollover determination device that determines rollover of a vehicle.
[0002]
[Prior art]
The vehicle rollover determination device described in Patent Document 1 calculates a roll angle of a vehicle by integrating a detected roll rate with a roll rate detecting unit that detects a rotational angular velocity acting around a longitudinal axis of the vehicle as a roll rate. A roll angle calculating means is provided, and when the roll angle and the roll rate belong to the hatched area of the roll rate-roll angle map stored in the ROM, it is determined that the vehicle rolls over.
[0003]
[Patent Document 1]
JP 2001-83172 A (pages 1 to 8, FIGS. 7 and 8)
[0004]
[Problems to be solved by the invention]
The vehicle rollover judging device described in Patent Document 1 has the following problems.
The roll angle calculated by the roll angle calculation means is an accumulation of the change, and does not take into account the initial absolute angle of the vehicle. For this reason, the magnitude of the initial absolute angle becomes an offset value of the roll angle in the map determination, and becomes a variation component in the rollover determination.
[0005]
Further, since the roll rate sensor is a precision device, the sensitivity may fluctuate due to factors such as temperature change and aging. In order to reduce the sensitivity fluctuation, a more reliable roll rate sensor is required, which has led to an increase in cost.
[0006]
An object of the present invention is to provide a vehicle rollover determination device that is excellent in rollover determination accuracy and that uses an inexpensive roll rate sensor.
[0007]
[Means for Solving the Problems]
[About claim 1]
The roll rate sensor detects a roll rate ωt acting around the longitudinal axis of the vehicle.
[0008]
The inclination sensor detects the inclination angle θ (absolute angle) of the vehicle.
The roll angle calculation means calculates the roll angle θt by integrating the roll rate ωt (relative angle).
[0009]
The vehicle state determination means determines whether the vehicle is stopped or running.
When the vehicle state determination unit determines that the vehicle is stopped, the sensor function check unit satisfies (roll angle θt−inclination angle θ) ≦ predetermined value A, indicating that the sensor function is within a predetermined tolerance. It is determined whether or not.
[0010]
If the inclination sensor and the roll rate sensor are in the ideal state, the inclination angle θ of the absolute angle detected by the inclination sensor is equal to the roll angle θt calculated by the roll rate calculation means in a state where the vehicle is stopped. {(Roll angle θt−inclination angle θ) = 0} ≦ predetermined value A holds.
[0011]
The map storage means stores a roll angle-roll rate map in which a rollover area determined to be a vehicle rollover is set.
When the sensor function checking unit determines that the sensor function is within a predetermined tolerance, the rollover region correction unit corrects the rollover region of the map storage unit by the deviation of (roll angle θt−inclination angle θ). It is preferable to perform the correction again at the next sensor function check.
[0012]
When it is determined that the sensor function is within the predetermined tolerance, the rollover determining means determines whether both the roll rate ωt and the roll angle θt belong to the corrected rollover region (rollover) or not (non-rollover). It is determined whether the vehicle has rolled over. If it is determined that the vehicle has rolled over, the occupant protection device is activated. Further, when it is determined that the sensor function is out of the predetermined tolerance, the operation of the occupant protection means is prohibited.
[0013]
The vehicle rollover determination device includes a roll angle θt (relative angle) calculated by integrating the roll rate ωt detected by the roll rate sensor while the vehicle is stopped, and a vehicle tilt angle θ (absolute angle) detected by the tilt sensor. ) To check the functions of the tilt sensor and the roll rate sensor.
[0014]
If the sensor function is determined to be within a predetermined tolerance, the vehicle in which the inclination sensor detects a roll angle θt (relative angle) calculated by integrating the roll rate ωt detected by the roll rate sensor while the vehicle is stopped. Is calibrated using the inclination angle θ (absolute angle) to correct the rollover area of the roll rate-roll angle map, so that the vehicle rollover determination accuracy is excellent.
[0015]
[About claim 2]
When the sensor function check unit confirms that (roll angle θt−inclination angle θ)> predetermined value A is satisfied, indicating that the sensor function is out of the predetermined tolerance, the vehicle rollover judging device determines that the sensor function has a predetermined value. The occupant protection device is configured to notify that the occupant protection device does not operate due to an out-of-tolerance by a notification unit.
[0016]
For this reason, the user can easily recognize whether or not the sensor function is within the predetermined tolerance based on whether or not the notification unit notifies.
[0017]
[About claim 3]
When the vehicle is stopped, a speed signal of zero vehicle speed is transmitted from the speed sensor, and a brake signal (when the foot brake is depressed) and a parking signal (the shift lever is at the parking position) are transmitted.
Therefore, the vehicle state determination means can easily determine whether the vehicle is stopped or running based on at least one of the speed signal, the brake signal, and the parking signal.
[0018]
BEST MODE FOR CARRYING OUT THE INVENTION
Next, a vehicle rollover judging device B according to an embodiment of the present invention (corresponding to claims 1 to 3) will be described with reference to FIGS.
[0019]
As shown in FIG. 1, a vehicle rollover judging device B includes a roll rate sensor 1 for detecting a roll rate ωt, an inclination sensor 2 for detecting an inclination angle θ, a microcomputer 3, and an occupant protection device for protecting an occupant. 4 and an alarm lamp 5 as a notification means.
[0020]
The roll rate sensor 1 is disposed in the airbag ECU, and detects a rotational angular velocity acting around a longitudinal axis of the vehicle as a roll rate ωt.
The inclination sensor 2 is arranged at an appropriate position of the vehicle, and detects the inclination angle θ of the vehicle.
[0021]
The microcomputer 3 that controls the occupant protection device 4 and the alarm lamp 5 includes a ROM 30 that stores a roll rate-roll angle map 32 in which a rollover area 31 (a hatched portion in FIG. 3A) is set. It operates based on the flowchart shown in FIG.
[0022]
The microcomputer 3 is electrically connected to the roll rate sensor 1 and the tilt sensor 2. Also, a speed signal 61 transmitted from the speed sensor, a brake signal 62 transmitted when the foot brake is depressed, and a parking signal 63 transmitted when the shift lever is at the parking position are input.
[0023]
In step s1, the roll rate ωt is input from the roll rate sensor 1 and the tilt angle θ is input from the tilt sensor 2.
[0024]
In step s2, the roll angle θt is calculated by integrating the roll rate ωt, and the process proceeds to step s3.
[0025]
In step s3, it is determined whether the vehicle is stopped (starting or stopped) or running based on the input state of the following signal. If the vehicle is stopped (YES), step s4 is performed. If the vehicle is traveling (YES), the process proceeds to step s6.
(Determined that the vehicle is stopped)
When a zero speed signal 61 is input from the speed sensor, when a brake signal 62 is input, or when a parking signal 63 is input.
In step s4 of FIG. 4, {Roll angle θt (relative angle) calculated by integrating roll rate ωt detected by roll rate sensor 1−inclination angle θ of vehicle detected by inclination sensor 2 (absolute angle)}> It is determined whether or not the predetermined value A is satisfied. If not (NO), the process proceeds to step s5, and if it is (YES), the process proceeds to step s8.
[0027]
In step s5, the rollover area 31 of the roll rate-roll angle map 32 shown in FIG. 3A is integrated with the roll rate ωt detected by the ｛roll rate sensor 1 as shown in FIG. 3B. Is corrected by the calculated roll angle θt (relative angle) −the tilt angle θ (absolute angle) of the vehicle detected by the tilt sensor 2.
Thus, the rollover region 31 in FIG. 3A is corrected to the rollover region 33 in FIG.
[0028]
In step s6, the roll rate ωt detected by the roll rate sensor 1 and the roll rate ωt are integrated and calculated in the rollover area 33 of the roll rate-roll angle map 32 shown in FIG. Rollover determination of the vehicle is performed based on whether both roll angles θt belong (rollover) or not (non-rollover), and when it is determined that the vehicle rolls over (YES), the process proceeds to step s7, and it is not determined that the vehicle rolls over. In this case (NO), the process returns to step s1.
[0029]
In step s7, the occupant protection device 4 (such as a curtain airbag or a pretensioner) is operated.
In step s8, a rollover determination prohibition output is sent to prohibit the operation of the occupant protection device 4.
In step s9, the alarm lamp 5 is turned on to notify the occupant that the sensor function is out of the predetermined tolerance.
[0030]
The vehicle rollover judging device B of the present embodiment has the following advantages.
[A] The vehicle rollover judging device B calculates the roll angle θt (relative angle) calculated by integrating the roll rate ωt detected by the roll rate sensor 1 −the vehicle tilt angle θ (absolute angle) detected by the tilt sensor 2. )｝> Whether the predetermined value A is satisfied (outside the predetermined tolerance) or not (inside the predetermined tolerance) is checked while the vehicle is stopped (steps s3 and s4), and the functions of the inclination sensor 2 and the roll rate sensor 1 are checked. Configuration.
For this reason, when the sensor function of any of the sensors is out of the predetermined tolerance, it can be detected that the sensor function is out of the predetermined tolerance early (when starting or stopping the vehicle).
[0031]
[A] When the sensor function is normal, the vehicle rollover judging device B converts the rollover area 31 of the roll rate-roll angle map 32 {(a) in FIG. Is corrected by the roll angle .theta.t (relative angle) calculated by integrating the roll rate .omega.t detected by the vehicle-the tilt angle .theta. (Absolute angle) of the vehicle detected by the tilt sensor 2 and the rollover region 33 {( b) Since it has been changed to｝ (step s5), the vehicle rollover determination accuracy is excellent.
For this reason, in order to reduce the sensitivity fluctuation of the roll rate sensor, a higher-precision roll rate sensor has been required, but an inexpensive roll rate sensor can be used.
[0032]
[C] The vehicle rollover judging device B, when (roll angle θt−inclination angle θ)> predetermined value A, which indicates that the sensor function is out of the predetermined tolerance, is established when the vehicle is stopped, the occupant protection device B In this configuration, the alarm lamp 5 is turned on to notify that the device 4 is not operating.
[0033]
For this reason, the user can easily recognize whether or not the sensor function is within the predetermined tolerance based on whether or not the alarm lamp 5 is turned on.
[0034]
Since the vehicle state is determined based on the input state of the brake signal 62 or the parking signal 63 or the input state of the speed signal 61 of zero speed, it can be easily determined whether the vehicle is stopped or running. .
[Brief description of the drawings]
FIG. 1 is a block diagram of a vehicle rollover judging device according to one embodiment of the present invention.
FIG. 2 is a block diagram showing a state of processing performed by a microcomputer of the vehicle rollover judging device.
3A is a graph showing a roll rate-roll angle map, and FIG. 3B is a graph showing a corrected roll rate-roll angle map.
FIG. 4 is a flowchart showing the operation of the vehicle rollover judging device.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 Roll rate sensor 2 Inclination sensor 3 Microcomputer (roll angle calculation means, vehicle state determination means, sensor function check means, rollover area correction means, rollover determination means)
4 Occupant protection device 5 Alarm lamp (reporting means)
30 ROM (map storage means)
31, 33 Rollover area (shaded area)
32 roll rate-roll angle map 61 speed signal 62 brake signal 63 parking signal A predetermined value B vehicle rollover judging device θ vehicle inclination angle ωt roll rate θt roll angle

Claims (3)

A roll rate sensor for detecting a roll rate ωt acting around a longitudinal axis of the vehicle;
An inclination sensor for detecting an inclination angle θ of the vehicle,
Roll angle calculating means for integrating the roll rate ωt to obtain a roll angle θt;
Vehicle state determining means for determining whether the vehicle is stopped or running,
When the vehicle state determination means determines that the vehicle is stopped, it is determined whether or not (roll angle θt−inclination angle θ) ≦ predetermined value A is satisfied, indicating that the sensor function is within a predetermined tolerance. Sensor function checking means for determining,
Map storage means for storing a roll rate-roll angle map in which a rollover area is set,
When the sensor function checking unit determines that the sensor function is within a predetermined tolerance, a rollover region correction unit that corrects the rollover region by a deviation of (roll angle θt−inclination angle θ);
If it is determined that the sensor function is within the predetermined tolerance, it is determined whether or not the vehicle rolls over by determining whether both the roll rate ωt and the roll angle θt belong to the corrected rollover region. A vehicle rollover judging device comprising: a rollover judging means for activating an occupant protection device when it is determined that the sensor function is out of a predetermined tolerance, and prohibiting the operation of the occupant protection device when the sensor function is determined to be outside a predetermined tolerance. When the sensor function is determined to be out of the predetermined tolerance, a notification unit for notifying that the sensor function is out of the predetermined tolerance is provided,
When the sensor function checking unit confirms that (roll angle θt−inclination angle θ)> predetermined value A is satisfied, indicating that the sensor function is out of a predetermined tolerance, the notification unit performs notification. The vehicle rollover judging device according to claim 1, wherein: The vehicle state discriminating means includes a speed signal transmitted from a speed sensor for detecting a traveling speed of the vehicle, a brake signal transmitted when a brake pedal is depressed, and a parking signal transmitted when the shift lever is at a parking position. The vehicle rollover judging device according to claim 1 or 2, wherein the vehicle state is determined based on at least one of the signals.

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