JP4516031B2 - Vehicle door monitoring device - Google Patents

Description

  The present invention relates to a vehicle door monitoring device that detects the opening and closing of a door when the vehicle is parked or stopped. More specifically, the present invention detects a change in air in a passenger compartment and opens the door based on the air change state. The present invention relates to an improvement of a determination operation in a configuration for determining whether to open or close.

  In order to prevent theft of the vehicle, there is a vehicle theft prevention device that monitors an intrusion into the passenger compartment and performs an alarm operation such as sounding an alarm with a loud sound when the intrusion is detected. This vehicle anti-theft device has various types of configurations such as detection methods and sensor means for detecting intrusion, and various proposals have been made conventionally.

For example, as can be seen in Patent Document 1 and the like, there is a method of detecting opening and closing of air in a passenger compartment and determining whether or not a door has been opened based on the air fluctuation state. The air in the passenger compartment depressurizes and increases as the door opens and closes, and exhibits characteristic fluctuations. In Patent Document 1, air fluctuations in the passenger compartment are detected by sensor means, and the characteristic fluctuations are identified on the circuit side of the subsequent stage to determine whether the door is opened or closed. Therefore, it is accurately monitored with a simple recognition algorithm. There is a merit that it can be made inexpensively because the configuration becomes simple.
JP 2001-93052 A

  However, when the vehicle door is opened gently, the output of the sensor means becomes small because the air fluctuation becomes small, and the determination operation becomes difficult unless the gain of the amplifier is increased on the subsequent circuit side. Come on. Therefore, if the gain of the amplifier is increased, the determination operation can be performed on the subsequent circuit side even if the air fluctuation is weak, but this time the possibility of causing a malfunction increases. For example, the passage of a large vehicle or the blowing of a gust causes air fluctuations that are transmitted to the vehicle and may therefore coincide with a recognition algorithm that detects that the vehicle door has been opened gently.

  The object of the present invention is to solve the above-mentioned problems. The purpose of this invention is to open the door of the vehicle quietly, so that the determination operation can be reliably performed for the opening of the door without being affected by the environment outside the vehicle. An object of the present invention is to provide a vehicle door monitoring device that is less likely to malfunction and can output an accurate determination result.

In order to achieve the above-described object, a vehicle door monitoring apparatus according to the present invention detects a change in air in a vehicle interior, and determines whether the door is opened or not based on the air change state. A variation sensor that detects a variation in air in the passenger compartment, a comparison unit that compares a signal based on the output of the variation sensor with a reference value and outputs an identification signal as a comparison result, and the door is opened from the identification signal. Determination means for determining whether or not it has been opened and closed, the comparison means is provided with at least three, the reference value is a strong pressure reduction first from the steady range in the calm, the second is a strong pressure increase, Third, when three values corresponding to weak decompression are set, and the determination means identifies a strong decompression within a predetermined time when a weak decompression is identified, and further identifies a strong pressure increase within a subsequent predetermined time Opened the door It determined, until the determination condition is when it becomes unsatisfied to elapse of the predetermined time prohibits new diagnostic operation, the determination condition during the prohibition of a new determination operation for not satisfied, identified weak vacuum Or when a weak pressure increase is identified, the prohibition of a new determination operation is extended for a predetermined time .
In this way, when the weak depressurization is identified or the weak pressure increase is identified during the prohibition of the judgment operation, it can be estimated that the fluctuation of the environment at the time of failure is continued, By further extending the prohibition of the determination operation in order to prevent malfunction, the opening / closing of the door can be monitored while preventing malfunction.

  In addition, at least four comparison means are provided, and the reference value is a strong pressure reduction, the second is a strong pressure increase, the third is a weak pressure reduction, and the fourth is a weak pressure increase when viewed from a steady range in a calm time. Four values corresponding to each other are set, and the determination means may be configured to prohibit a new determination operation until a predetermined time elapses when a weak pressure increase is identified. When these conditions are met. This is because it can be estimated that there are environmental fluctuations and the like, and malfunction is prevented.

  The fluctuation sensor can be a microphone that detects air vibrations.

  With this configuration, in the present invention, since identification is performed at at least three levels, it is possible to identify even if the air fluctuation (pressure change) is weak. When a large vehicle passes or a gust of wind blows, there is no sudden large pressure change, and there is a small pressure change immediately before. Since the recognition algorithm is designed to discriminate the subsequent second and third pressure changes in terms of time and level, it is possible to correctly determine when the door is open and when it is not. Therefore, even if the gain of the amplifier is set large on the circuit side subsequent to the sensor means, no erroneous determination operation is performed.

  In the vehicle door monitoring apparatus according to the present invention, since identification is performed at at least three levels, it is possible to identify even if the air fluctuation (pressure change) is weak. The determination operation by the determination means is a recognition algorithm in which the subsequent second and third pressure changes are identified in terms of time and level, so that it is possible to correctly determine when the door is opened and when it is not. Therefore, even if the gain of the amplifier is set large on the circuit side subsequent to the sensor means, no erroneous determination operation is performed. Then, by setting the gain of the amplifier to be large, even when the door of the vehicle is opened gently, the determination operation for the door opening can be reliably performed. As a result, it is difficult to cause a malfunction without being affected by the environment outside the vehicle, and an accurate determination result can be output.

  FIG. 1 shows a preferred embodiment of the present invention. In this embodiment, the vehicle door monitoring apparatus compares the fluctuation sensor 1 that detects fluctuations in air, the high-pass filter (HPF) 2 for waveform processing, the amplifier 3, the integration circuit 4, and the reference value. Are provided with four comparators 51, 52, 53, and 54 for determining whether the door has been opened or not based on the identification signals. And the determination part 6 is the structure which detects the fluctuation | variation of the air in a vehicle interior, determines opening / closing whether the door was opened from the fluctuation | variation state of the air, and outputs the signal according to determination to an alarm means etc. It has become.

  A microphone is used as the fluctuation sensor 1 and is arranged in the passenger compartment to detect sound. The sound is vibration of air, and the microphone is a sensor that detects a change in sound pressure, that is, a pressure change from atmospheric pressure. Therefore, the fluctuation sensor 1 detects a fluctuation of air in the passenger compartment. Since the detection target called sound pressure is a change in air pressure, the fluctuation sensor 1 is not limited to a microphone, and for example, a pressure sensor, a Doppler sensor, an ultrasonic sensor, or the like can be used to detect slight fluctuations in air pressure. Any sensor means can be used.

  This fluctuation sensor 1 is connected to the HPF 2. The HPF 2, the amplifier 3, and the integrating circuit 4 are connected in the same order, and the waveform of the output of the fluctuation sensor 1 is appropriately processed. That is, an unnecessary low-frequency component is attenuated from the output signal of the fluctuation sensor 1 (HPF2), the extracted high-frequency component signal is amplified (amplifier 3), and a short-cycle noise component is removed by integration (integration) The output of the circuit 4) and the integrating circuit 4 is sent to the four comparators 51, 52, 53, 54.

  The four comparators 51, 52, 53, 54 set reference values for comparison, respectively, and identify the air fluctuation status at four levels. That is, the reference value for comparison corresponds to the pressure value of air in the passenger compartment, and the comparator 51 has a strong pressure reduction (d1), the comparator 52 has a strong pressure increase (d2), and the comparator 53 has a The weak pressure reduction (d3) and the comparator 54 set four values respectively corresponding to the weak pressure increase (d4). These four comparators 51, 52, 53, and 54 are connected to the determination unit 6 via the inverter 7, respectively, and send out identification signals for the four levels. The inverter 7 is not necessarily required on the output side of each comparator, and the signal sent to the determination unit 6 may be either positive logic or negative logic.

For the four comparators, the output of the integrating circuit 4 is connected to the-terminal for the comparator 51 for identifying strong pressure reduction (d1), and to the + terminal for the comparator 52 for identifying strong pressure increase (d2). The comparator 53 for identifying weak pressure reduction (d3) is sent to the-terminal, and the comparator 54 for identifying weak pressure increase (d4) is sent to the + terminal. Reference voltages Th2, Th4, Th3, and Th1 are applied to the other input terminals of the comparators 51, 52, 53, and 54, and these reference voltages are connected in series between the power supply voltage Vcc and the ground by five resistors R5 and R2. , R4, R3, R1 are connected and divided. These reference voltages are
Th2>Th4>Th3> Th1
It is set to a large and small relationship.

  Therefore, the comparator 51 outputs a pulse when the detection signal (pressure change) becomes equal to or less than Th1, and outputs an identification signal d1 indicating strong decompression. The comparator 52 outputs a pulse when the detection signal (pressure change) becomes equal to or greater than Th2, and outputs an identification signal d2 indicating a strong pressure increase. The comparator 53 outputs a pulse when the detection signal (pressure change) becomes equal to or less than Th3, and outputs an identification signal d3 indicating weak decompression. The comparator 54 outputs a pulse when the detection signal (pressure change) becomes equal to or greater than Th4, and outputs an identification signal d4 indicating a weak pressure increase.

  It is preferable that Th3 related to weak pressure reduction and Th4 related to weak pressure increase are appropriately changed according to ambient noise and the like, and malfunction can be prevented by appropriately changing the threshold value. To change the setting, for example, the setting resistor of the reference voltage is replaced with a variable resistor and adjusted appropriately, or the reference voltage is generated by the CPU when the setting switch connected to the CPU is pressed so that the CPU generates the reference voltage. The reference value may be gradually increased from a small value, and a predetermined margin value may be taken as the reference value from the point where the weak depressurization and weak pressure increase identification signals are not generated.

  The determination unit 6 is a so-called computer, and performs a determination operation based on each identification signal input from the input port, and outputs a control command corresponding to the determination to each device on the output port side. . That is, the determination unit 6 determines whether or not there is a pressure change when the door is opened based on the timing of the four identification signals, and generates a control command according to the determination. Since devices such as devices are connected, it is possible to cause them to perform appropriate alarm operations.

  As a determination operation, the determination unit 6 identifies a strong pressure reduction (d1) within a predetermined time when a weak pressure reduction (d3) is identified, and further identifies a strong pressure increase (d2) within a subsequent predetermined time. It is determined that the door is opened, and when the determination condition is not satisfied, an operation for prohibiting a new determination operation is performed until a predetermined time elapses. For example, the timing in the determination operation is set within 20 ms for detection of strong pressure reduction (d1) following weak pressure reduction (d3), and within 200 ms for detection of subsequent strong pressure increase (d2), and the determination condition is not satisfied. The prohibition time is set to 1 s.

  Note that a configuration in which a comparator is not used as the comparison unit may be employed. For example, digital data may be sent to the determination unit 6 using an AD converter, and the determination unit 6 may perform comparison processing.

(Determination of door opening operation)
FIG. 2 is a timing diagram showing signal waveforms at various parts when the vehicle door is opened. In the vehicle, when any door is opened or closed, the movement of air occurs in the passenger compartment, causing a change in pressure. The movement of air is detected by the fluctuation sensor 1 as a sound pressure.

  When one of the doors is opened from a calm state where all the doors and windows are closed, the fluctuation sensor 2 outputs a mountain-shaped waveform having valleys before and after as shown in FIG. When all doors and windows are closed, there is almost no movement of air in the passenger compartment, and the pressure is maintained at a substantially constant value (steady pressure). At this time, the output of the fluctuation sensor 1 does not change much although there is a minute fluctuation due to the detection of noise. Here, when one of the doors is opened, the air around the door attempts to flow out of the passenger compartment following the opening door (referred to as a negative flow). There is movement and the pressure in the passenger compartment decreases. And since the door opens, the inside and outside of the passenger compartment are connected, and air moves toward equilibrium, so air flows into the passenger compartment from the outside, creating a flow opposite to the initial (positive flow), and this shaking By returning, the pressure of the air in the passenger compartment is higher than the steady pressure. Thereafter, the air that has flowed too much into the passenger compartment is released to the outside (negative flow), and returns to a stable state (steady pressure) in which there is almost no air movement.

  In this way, in the closed space, when the door is opened, the pressure in the space once decreases and starts to increase from the reduced pressure value u0, and then reverses and shows the increased pressure value h0 at a position exceeding the steady pressure. Then, after this, the pressure is reduced again, and after reaching a reduced pressure value u1 that is equal to or lower than the steady pressure, the characteristic returns to the steady pressure. That is, in the door opening operation, as shown in FIG. 2A, the fluctuation sensor 1 outputs a waveform signal such that the reduced pressure value u0, the increased pressure value h0, and the reduced pressure value u1 are connected in the same order. As shown in FIG. 2B, this signal passes through the HPF 2 and the amplifier 3 and becomes a trapezoidal wave in which valleys, peaks and valleys are successively connected. The valley corresponds to the reduced pressure value u0 or the reduced pressure value u1. It corresponds to the pressure increase value h0 and is sent to the next integration circuit 4.

  As shown in FIG. 2C, the output of the integration circuit 4 has a dull rise (fall), so that the comparators 51, 52, 53, and 54 in the next stage can optimize the comparison timing. Therefore, the comparator 51 outputs a portion that falls below the reference voltage Th1 set corresponding to a strong pressure reduction as seen from the steady range during calm time, and a portion corresponding to the pressure reduction values u0 and u1 detected by the fluctuation sensor 1 is the steady range. When the value is significantly below the value, only the relevant part is output, and the pulse waveform d1 is output. In the comparator 52, a portion exceeding the reference voltage Th2 set corresponding to a strong pressure increase as seen from the steady range during calm time is output, and a portion corresponding to the pressure increase value h0 detected by the fluctuation sensor 1 increases the steady range. When exceeding, only the part is output, and the pulse waveform d2 is output. At this time, since there is a strong pressure reduction and a strong pressure increase, the comparators 53 and 54 for identifying weak pressure reduction and weak pressure pressure are naturally identified, and similarly, pulse waveforms d3 and d4 are output, and these are pulses. It is output at a time slightly earlier than the waveforms d1 and d2.

  The determination unit 6 identifies a strong pressure reduction (d1) within a predetermined time when a weak pressure reduction (d3) is identified, and further identifies a strong pressure increase (d2) within a predetermined time, and the door is opened. Since the determination is made, the sound pressure detection shown in FIG. 2, that is, the air fluctuation state, is a determination that the operation of opening the door has been performed. That is, in the door opening operation, a large pressure change suddenly occurs from a calm pressure state, and when the large pressure change can be identified according to the present invention, the small pressure change is also identified immediately before. It is possible to determine that the door has been opened if it can be continuously identified.

  By the way, when the door is opened slowly, the second trough (decompression value u1) may not necessarily appear in the output of the fluctuation sensor 1. However, as described above, this is not involved in the recognition algorithm of the present invention, and therefore the door opening operation can be correctly determined even when the door is opened slowly.

(Passing large vehicles)
FIG. 3 is a timing diagram showing signal waveforms at various parts when a large vehicle passes. When a large vehicle passes, the air fluctuation (pressure change) does not occur suddenly, but the pressure change is small while the large vehicle is far away, and increases as it approaches. This is transmitted to the vehicle, and the fluctuation sensor 1 outputs a vibration waveform as shown in FIG. 3A to detect a pressure change whose amplitude increases as the large vehicle approaches.

  As shown in FIG. 3C, the four comparators first identify a weak pressure change, so there is an identification in order from one of the comparators 53 and 54 for identifying weak pressure reduction and weak pressure increase. , And output sequentially from either one of the pulse waveforms d3 and d4. Subsequently, identification is made in order from either one of the comparators 51 and 52 for discriminating strong pressure reduction and strong pressure increase. Similarly, the pulse waveforms d1 and d2 are output in order from either one, and these are pulse waveforms d3 and d4. Will be output later.

  This does not hold in view of the condition of the determination operation in the determination unit 6, and the sound pressure detection, that is, the air fluctuation state shown in FIG. 3 does not determine that the door opening operation has been performed. Until the time elapses, an operation for prohibiting a new determination operation is performed. That is, when a large vehicle passes, a large pressure change gradually occurs from a calm pressure state, and according to the present invention, it is not determined that the determination condition is not satisfied and the door is opened.

(When a gust of wind blows)
FIG. 4 is a timing chart showing signal waveforms at various parts when a gust of wind blows. In a situation where a gust of wind blows, a certain amount of wind is constantly blowing, and in a situation where the background wind is blowing, a strong gust of wind sometimes blows. This is transmitted to the vehicle, and the fluctuation sensor 1 outputs a vibration waveform as shown in FIG. 4A, continuously detects a small amplitude pressure change (background wind), and sometimes a large pressure change (gust wind). Is detected.

  As shown in FIG. 4C, the four comparators first identify a weak pressure change. Therefore, the comparators 53 and 54 for identifying weak pressure reduction and weak pressure increase have identification, and the pulse One of the waveforms d3 and d4 is output. Subsequently, any one of the comparators 51 and 52 for identifying strong pressure reduction and strong pressure increase is identified, and similarly, either of the pulse waveforms d1 and d2 is output. However, these identification signals have no regularity and are output randomly.

  This does not hold when viewed from the condition of the determination operation in the determination unit 6, and the sound pressure detection, that is, the air fluctuation state shown in FIG. 4 is not a determination that the door opening operation has been performed. Until the time elapses, an operation for prohibiting a new determination operation is performed. In other words, the situation in which the gust blows is a random situation in which a large pressure change occurs occasionally while there is a continuous pressure change with a small amplitude. Therefore, according to the present invention, the determination condition is not satisfied and it is not determined that the door is opened.

  5 and 6 are flowcharts showing a routine for opening / closing whether or not the door has been opened. The determination unit 6 performs the determination operation according to the procedure shown in FIGS. When the determination routine is started, an interruption of the identification signal d3 is determined in processing step S2. Here, when the weak decompression (d3) is identified (Yes), the door may have been opened, so the process proceeds to the process step S4 and thereafter, and if (No), the process proceeds to the process step S3.

  In processing step S3, the interruption of the identification signal d4 is determined. Here, when the weak pressure increase (d4) is identified (Yes), it is determined that the vibration is caused by the environment, and the process proceeds to a determination operation prohibition process after process step S15. In the fluctuation of the environment, as shown in FIG. 7, the subsequent recognition may coincide with the door open determination condition. This may happen by mistake, but causes a malfunction. However, here, since the interruption of the identification signal d4 is determined in the processing step S3, it is possible to distinguish environmental fluctuations and the like, and it is possible to reliably perform the determination operation for the door opening.

  In process step S4, the 20 ms timer 20 is reset and started, which is the time limit for identification of the subsequent strong decompression (d1). Next, the interrupts of the identification signals d3, d4, and d1 are sequentially determined in processing steps S5, S6, and S7.

  When weak decompression (d3) is identified in processing step S5 (Yes), weak decompression (d3) is continuously identified, so it is determined that weak decompression (d3) in processing step S2 is vibration due to the environment. Then, the process proceeds to the determination operation prohibition process after process step S15. When the weak pressure increase (d4) is identified in the processing step S6 (Yes), the pressure change is reversed, so that the weak pressure reduction (d3) in the processing step S2 is determined as vibration due to the environment and the processing step S15 and thereafter. It moves to the prohibition process of the judgment operation. When the strong pressure reduction (d1) is identified in the processing step S7 (Yes), there is a possibility that the door has been opened, and the process proceeds to the processing after the processing step S9. These processing steps S5, S6, and S7 are repeatedly executed until the timer 20 times out according to the determination in the subsequent processing step S8. If the timer 20 reaches 0 in the processing step S8 (Yes), the processing step S2 The weak decompression (d3) is determined to be vibration due to the environment, and the process proceeds to the prohibition process of the determination operation after process step S15.

  In process step S9, the 200 ms timer 200 is reset and started, which is the time limit for the identification of the subsequent strong pressure increase (d2). Next, the interrupts of the identification signals d2 and d3 are sequentially determined in processing steps S10 and S11.

  When the strong pressure increase (d2) is identified in the processing step S10 (Yes), it can be determined that the door is opened, the process proceeds to the processing step S13, the determination result is output, and the determination routine is paused (S14). When weak pressure reduction (d3) is identified in processing step S11 (Yes), the change in pressure reduction is continuously identified. Therefore, the determination condition is not satisfied, and the process proceeds to the determination operation prohibition processing after processing step S15. These processing steps S10 and S11 are repeatedly executed until the timer 200 times out by the determination in the subsequent processing step S12. If the timer 200 reaches 0 in processing step S12 (Yes), the determination condition is not satisfied. The process proceeds to a determination operation prohibition process after process step S15.

  After processing step S15, although some pressure change has been identified, when the condition is not satisfied to determine that the door has been opened, a process of prohibiting the determination operation is performed until the pressure change has subsided. First, in processing step S15, the 1s timer 1000 is reset and started, which is a time limit for prohibiting the determination operation. Next, the interrupts of the identification signals d3 and d4 are sequentially determined in processing steps S16 and S17.

  If weak pressure reduction (d3) is identified in processing step S16 (Yes), the pressure change has not yet subsided, so the procedure returns to step 15 and the 1s timer 1000 is reset and restarted. When a weak pressure increase (d4) is identified in processing step S17 (Yes), the pressure change has not yet subsided, so the process returns to step 15 and the 1s timer 1000 is reset and restarted. These processing steps S16 and S17 are repeatedly executed until the timer 1000 times out according to the determination in the subsequent processing step S18. If the timer 1000 reaches 0 in processing step S18 (Yes), the pressure change converges. Therefore, the process returns to the processing step S2, and a new determination operation is continued.

  Thus, in the present invention, since identification is performed at four levels, it is possible to identify even if air fluctuation (pressure change) is weak. When a large vehicle passes or a gust of wind blows, a large pressure change does not occur suddenly and there is a small pressure change immediately before. Thus, a small pressure change immediately before that depends on the identification. Since the recognition algorithm is designed to discriminate the subsequent second and third pressure changes in terms of time and level, it is possible to correctly determine when the door is opened and when it is not.

  Therefore, even if the gain of the amplifier 3 is set large, no erroneous determination operation is performed. Then, by setting the gain of the amplifier 3 large, it is possible to reliably perform the determination operation for opening the door even when the door of the vehicle is gently opened. As a result, it is difficult to cause a malfunction without being affected by the environment outside the vehicle, and an accurate determination result can be output.

  In the above-described embodiment and the like, the comparator is used for level determination. However, the present invention is not limited to this. For example, the sensor output (analog) is converted into digital data using an AD converter, and the software by the CPU is used. Processing may be performed by wear.

It is a lineblock diagram showing a suitable embodiment of a vehicle door monitoring device concerning the present invention. It is a timing diagram which shows the signal waveform of each part when the door of a vehicle opens. It is a timing diagram which shows the signal waveform of each part when a large sized vehicle passes. It is a timing diagram which shows the signal waveform of each part at the time of a gust. It is a part of flowchart which shows the determination routine of opening / closing whether the door was opened. It is a part of flowchart which shows the determination routine of opening / closing whether the door was opened. It is a timing diagram which shows the signal waveform of each part in the fluctuation of an environment.

Explanation of symbols

1 Fluctuation sensor 2 High pass filter (HPF)
3 Amplifier 4 Integration Circuit 51, 52, 53, 54 Comparator 6 Determination Unit 7 Inverter

Claims (3)

A vehicle door monitoring device that detects a change in air in a passenger compartment and determines whether the door has been opened or not based on the air fluctuation state.
A variation sensor for detecting a variation in air in the passenger compartment, a comparison means for comparing a signal based on the output of the variation sensor with a reference value and outputting an identification signal as a comparison result, and whether the door has been opened from the identification signal Determination means for determining whether to open or close,
The comparison means includes at least three,
The reference value is set to three values corresponding to a strong pressure reduction, a second pressure increase, and a third weak pressure reduction as seen from the steady range during calm time,
The determination hand stage, weak reduced pressure followed upon identifying identifies a strong vacuum within the predetermined time, if you have identified a strong pressure increase in the further subsequent predetermined time is judged that the door is opened, the determination condition and unsatisfied When a new pressure is detected, a new judgment operation is prohibited until the predetermined time has elapsed , and a weak pressure reduction is identified or a weak pressure increase is identified while the new judgment operation is prohibited because the judgment condition is not satisfied. In such a case, the vehicle door monitoring device is configured to extend the prohibition of a new determination operation for a predetermined time . The comparison means includes at least four,
The reference value is set to four values corresponding to a strong pressure reduction, a second pressure increase, a third pressure reduction, and a fourth pressure increase when viewed from the steady range during the calm period,
2. The vehicle door monitoring apparatus according to claim 1, wherein, when a weak pressure increase is identified, the determination unit prohibits a new determination operation until a predetermined time elapses. The variation sensor may vehicle door monitoring device as claimed in claim 1 or 2, characterized in that a microphone for detecting a vibration of air.

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