JP5454937B2 - Vehicle object detection device - Google Patents

Description

  The present invention relates to an object detection device for a vehicle, and more particularly to an object detection device for a vehicle in which an object present around a vehicle is detected by an object detection sensor such as an ultrasonic sensor.

  An object detection device for a vehicle usually has an ultrasonic sensor (object detection sensor) that is provided in the periphery of the host vehicle and that receives a reflected wave reflected by an object such as an obstacle and a predetermined prohibition condition. When the condition is satisfied, the ultrasonic sensor is stopped and controlled, and when the prohibition condition is released, the ultrasonic sensor is driven and controlled so as to emit the emission wave, and is present around the vehicle based on transmission / reception of the ultrasonic sensor. Determination means for determining the presence or absence of an object to be detected, and notification means for notifying the driver when the determination means determines that there is an object around the host vehicle. For example, in the ultrasonic object detection device described in Patent Document 1 below, an external supersonic wave such as a wind noise generated when the other vehicle travels at high speed or an ultrasonic wave from the ultrasonic object detection device mounted on the other vehicle is used. In order to prevent erroneous notification due to superimposition of sound wave noise on the received wave, the function of the ultrasonic object detection device is stopped when external ultrasonic noise is detected.

Japanese Patent Laid-Open No. 7-128445

By the way, in the object detection device represented by the ultrasonic object detection device described in Patent Document 1, various electronic devices (for example, other vehicles) outside the vehicle are emitted by emitting unnecessary ultrasonic waves to the outside when the vehicle is parked. In general, a prohibition process for prohibiting the operation of the ultrasonic sensor is executed when the shift range is switched to the P (parking) range so as not to cause a malfunction of the ultrasonic object detection apparatus (such as the ultrasonic object detection apparatus). . In this case, depending on the vehicle model, it is conceivable to execute the prohibition process when the parking brake is in an operating state (for example, a manual transmission vehicle). That is, even when the parking brake is in the activated state, it is conceivable that the malfunction prevention is effectively performed on the assumption that the vehicle is not moving as in the case where the shift range is switched to the P range.
However, when the parking brake operation is detected and the prohibition process is performed, for example, if the accelerator pedal is depressed while the shift range is switched to the D (drive) range, the vehicle actually moves. There is a problem that even if an obstacle is approached, the driver cannot be notified of the fact.

  The present invention has been made in order to cope with the above-described problem, and the purpose of the present invention is when a vehicle starts to move even when the operation of an object detection sensor represented by an ultrasonic sensor is prohibited. Exceptionally, the object detection sensor is operated to effectively perform object detection.

Means for Solving the Problems and Effects of the Invention

In order to achieve the above object, the present invention provides an object detection sensor that is provided in the periphery of the host vehicle and that receives a reflected wave that is emitted from an emitted wave and reflected by an object such as an obstacle, and a predetermined prohibition condition is satisfied. Controls stopping of the object detection sensor, and when the prohibition condition is canceled, the control means for driving the object detection sensor to emit the emission wave, and the object existing around the vehicle based on transmission / reception of the object detection sensor In the vehicle object detection device comprising: a determination unit that determines the presence or absence of the vehicle; and a notification unit that notifies the driver when the determination unit determines that there is an object around the host vehicle.
Equipped with a vehicle speed sensor that detects the vehicle speed of the host vehicle,
When the prohibition condition is released , the control means drives and controls the object detection sensor on the condition that the vehicle speed detected by the vehicle speed sensor is lower than a predetermined value, and even if the prohibition condition is not released, based on the vehicle speed detected by the vehicle speed sensor, the vehicle is determined that no such unit is stopped, characterized in that it is configured to drive and control the object detection sensor.

  According to the present invention, even when the prohibition condition is not released (when the prohibition mode state is maintained), the object detection sensor is driven and controlled on condition that the host vehicle is not stopped. For this reason, accidental collision can be satisfactorily prevented by effectively utilizing the object detection sensor and notifying the driver of the approach of the vehicle to the obstacle.

  In this case, it is preferable that the prohibition condition includes turning on a parking brake switch indicating that a parking brake provided in the host vehicle is in an operating state. Here, the parking brake operates a braking device for some wheels by a mechanical operation mechanism such as a wire in order to prevent the host vehicle from moving during parking or stopping, and includes a depression pedal. There are a stepping type and a lever type with a pull-in lever.

  As described above, even when the parking brake is in an activated state, for example, when the shift range is switched to the drive range, the vehicle starts to move when the accelerator pedal is depressed. Therefore, even in such a case, the driver can be almost surely notified that the obstacle has been approached.

  The control means may be configured to determine that the host vehicle is not stopped based on a vehicle speed detected by a vehicle speed sensor provided in the host vehicle. An object detection sensor such as an ultrasonic sensor is often set as one of operating conditions that the host vehicle is in a predetermined low speed state (for example, less than 15 km / h). For this reason, the configuration of the object detection device can be simplified by determining that the vehicle is not in a stopped state based on the vehicle speed detected by the vehicle speed sensor. In addition to the vehicle speed sensor, for example, a camera capable of imaging the periphery of the vehicle is provided, and various sensors and electronic devices mounted on the vehicle are used, such as determining that the host vehicle is not in a stopped state in accordance with a change in the captured scenery. It is also possible to use equipment.

Sectional drawing which shows the ultrasonic sensor as an example of an object detection means. 1 is a schematic view of a vehicle object detection device according to the present invention. 1 is a block diagram of a vehicle object detection device according to the present invention. The flowchart which shows the object detection program performed by the control circuit of FIG. Explanatory drawing which illustrates the various waveforms based on transmission / reception of an ultrasonic sensor.

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

  FIG. 1 shows an ultrasonic sensor unit (hereinafter simply referred to as an ultrasonic sensor) 10 as an object detection sensor used in a vehicle object detection apparatus 1 (see FIGS. 2 and 3) according to the present invention. The ultrasonic sensor 10 is, for example, a transmitter / receiver type that vibrates a piezoelectric ceramic vibrator by a piezoelectric effect, emits ultrasonic waves, and converts ultrasonic vibrations incident on the piezoelectric ceramic vibrator into an electric signal. It includes an ultrasonic microphone 11, a case 12, a control board 13, and the like.

  The ultrasonic microphone (microphone) 11 incorporates the piezoelectric ceramic vibrator described above. The ultrasonic microphone 11 is accommodated in the case 12 via the cushion material 14.

  The case 12 is of a connector integrated type, and is integrally assembled to the vehicle bumper BP via an annular bezel 15 having a flange portion by a spring member (not shown). The case 12 is sealed by a cover 17 in a state in which the ultrasonic microphone 11, the control board 13, a filler (for example, urethane) and the like are accommodated.

  As shown in FIG. 2, the control board 13 includes a transmission circuit 13a, a reception circuit 13b, a waveform shaping circuit 13c, a distance calculation circuit 13d, and a communication circuit 13e. The transmission circuit 13a is a circuit that transmits ultrasonic waves, and includes, for example, an oscillation circuit that oscillates an ultrasonic signal of about 66.7 kHz, and a drive circuit that drives the piezoelectric ceramic vibrator described above. .

  The wave receiving circuit 13b is a circuit that receives a reflected wave based on the emitted wave transmitted from the wave transmitting circuit 13a, and includes a detection circuit using an operational amplifier, for example. The waveform shaping circuit 13c is a circuit for adjusting a detection signal from the wave receiving circuit 13b, and includes, for example, a rectifier circuit, a smoothing circuit, a filter circuit, a level determination circuit, and the like.

  The distance calculation circuit 13d measures the time until the emission wave is reflected and returned based on the waveform of the reflected wave obtained by the waveform shaping circuit 13c, calculates the distance to the object based on the time, Or it is a circuit which calculates the length of a reverberation wave. The communication circuit 13e is a circuit that transmits a detection signal (for example, a serial signal) indicating the distance calculated by the distance calculation circuit 13d to the ECU 20.

  As shown in FIG. 3, the ultrasonic sensor 10 described above is disposed at each corner position of the bumper BP provided at the front and rear of the vehicle and at the center position (two places on the left and right sides) of the rear bumper BP. Specifically, the ultrasonic sensor 10 includes an FL corner sensor 10a at the left front position, an FR corner sensor 10b at the right front position, an RL corner sensor 10c at the left rear position, an RR corner sensor 10d at the right rear position, and a rear left shift. The RLC center sensor 10e at the center position and the RRC center sensor 10f at the rear right side center position are provided.

  Each of the sensors 10a to 10f is provided with terminals (for example, six terminals) for connecting signal lines (in and out) for power supply, GND, and communication. Each terminal of the FL corner sensor 10a is connected to a corresponding terminal of the ECU 20 via a signal line, and is connected to a corresponding terminal of the FR corner sensor 10b via a signal line.

  Similarly, each terminal of the RL corner sensor 10c is connected to a corresponding terminal of the ECU 20 via a signal line, and is connected to a corresponding terminal of the RLC center sensor 10e via a signal line. Sequentially, each terminal of the RLC center sensor 10e is connected to a corresponding terminal of the RRC center sensor 10f, and each terminal of the RRC center sensor 10f is connected to a corresponding terminal of the RR corner sensor 10d.

  The ECU (Electronic Control Unit) 20 includes communication circuits 21F and 21R, a power supply circuit 22, buzzer drive circuits 23F and 23R, a display drive circuit 24, various interface (I / F) circuits 25 to 27, and a control to which these are connected. A circuit 28 is provided.

  The communication circuit 21F inputs detection signals representing distances from the FL corner sensor 10a and the FR corner sensor 10b to the control circuit 28, respectively. The communication circuit 21R inputs, to the control circuit 28, detection signals indicating distances from the RL corner sensor 10c, the RR corner sensor 10d, the RLC center sensor 10e, and the RRC center sensor 10f, respectively.

  The power supply circuit 22 has a function of changing the voltage (12V) of the battery B to a constant voltage (5V, 8V), and is connected to the battery B via the main switch MA and the ignition switch IG. The buzzer drive circuits 23F and 23R send drive currents to the buzzers 31 and 32 (notification means) provided, for example, at the front and rear of the vehicle interior, respectively. The display drive circuit 24 supplies a drive current to the display device 33 (notification means) provided on the operation panel in the vehicle compartment.

  When the shift range (shift position) is switched to the R (reverse) range, the interface (I / F) circuit 25 inputs a detection signal indicating the switching to the control circuit 28. When the parking brake is activated and the parking brake switch PKB is turned on, the interface (I / F) circuit 26 inputs an on signal to the control circuit 28. The interface (I / F) circuit 27 inputs a detection signal representing the vehicle speed detected by the vehicle speed sensor 34 to the control circuit 28.

  The control circuit 28 (control means, determination means, notification means) includes a non-volatile memory (storage means) such as a CPU, ROM, RAM, flash memory, I / O, A / D converter, D / A converter, and the like. The main component is a buzzer drive circuit that repeatedly executes the object detection program of FIG. 4 stored in the ROM or the like every predetermined time after the main switch MA and the ignition switch IG are turned on, and outputs a drive signal corresponding to the execution. 23F and 23R and the display drive circuit 24.

  Next, the operation of the first embodiment configured as described above will be described. When the driver turns on the ignition switch IG and then turns on the main switch MA, the control circuit 28 starts executing the object detection program of FIG.

  After performing the initialization process (S1), the control circuit 28 determines whether PKB is on, that is, whether the parking brake is in operation (S2).

  If PKB is off (S2: NO), the control circuit 28 determines whether or not the shift range is the R range (S3). Whether the shift range is the R range (S3: YES), or the shift range is a D (drive) range other than the R range and the vehicle is in a low speed state (the vehicle speed based on the vehicle speed signal from the vehicle speed sensor 34 is, for example, 15 km / If it is less than h) (S3: NO, S4: YES), the processing after S5 is executed.

  Specifically, when the shift range is switched to a D range or the like other than the R range, the control circuit 28 drives and controls the corner sensors 10a to 10d and inputs detection signals of the corner sensors 10a to 10d. On the other hand, when the shift range is switched to the R range, the corner sensors 10a to 10d and the center sensors 10e and 10f are driven and controlled, and detection signals of the sensors 10a to 10f are input (S5).

  Next, the control circuit 28 executes object detection processing based on detection signals from the sensors 10a to 10d (S6). For example, as shown in FIG. 5A, when none of the sensors 10a to 10d receives the reflected wave U1 ′ based on the emitted wave U1 transmitted by itself, the front and rear buzzers 31 and 32 and the display 33 are stopped. Maintain state.

  On the other hand, as shown in FIG. 5B, for example, when the reflected wave U1 ′ based on the emission wave U1 transmitted by itself is received by at least one of the sensors 10a to 10d, According to the positional relationship with the object, the sounding mode (intermittent sound, fast intermittent sound, continuous sound) of the buzzers 31 and 32 and the display mode (flashing, lighting) of the display 33 are determined, and the determination should be executed. Drive signals are output to the buzzer drive circuits 23F and 23R and the display drive circuit 24.

  In the first embodiment, when the PKB is on, the prohibition condition for prohibiting the operation of the ultrasonic sensor 10 is set, and the control circuit 28 stops the ultrasonic sensor 10 in principle unless the prohibition condition is canceled. The prohibition process to be controlled is executed. By the way, in the first embodiment, when the prohibition process is executed using the PKB on signal, the vehicle speed signal from the vehicle speed sensor 34 is referred to (S8), and the PKB on signal is used alone. The prohibition process is not performed.

  Specifically, the control circuit 28 prohibits the operation of the ultrasonic sensor 10 only when PKB is on and the host vehicle is stopped (the vehicle speed based on the vehicle speed signal from the vehicle speed sensor 34 is 0). (S2, S8: YES) Even if the PKB is on, if the host vehicle is moving (vehicle speed ≠ 0), the processing after S5 is executed (S2: YES, S8: NO). In other words, even if the parking brake is in operation, if the shift range is the D range, the vehicle starts moving when the accelerator pedal is depressed. Therefore, when using the PKB on signal, the vehicle speed signal from the vehicle speed sensor 34 is also confirmed. Then, the determination process of S2 and the determination process of S8 are determined by AND and the prohibition process is performed.

  As is clear from the above description, according to the first embodiment, even when the parking brake, which is one of the prohibited conditions, is not released (S2: YES), the host vehicle is not stopped. If this happens (S8: NO), the ultrasonic sensor 10 is driven and controlled (S5). For this reason, it is possible to effectively prevent an unexpected collision by effectively using the ultrasonic sensor 10 and notifying the driver of the approach of the vehicle to the obstacle by the display device 33.

  Moreover, in the said Example 1, since it determines with the vehicle not being a stop state based on the vehicle speed signal detected by the vehicle speed sensor 34 (S8), the structure of the vehicle object detection apparatus 1 can be simplified.

  In the first embodiment, the ultrasonic sensor 10 is used as the object detection sensor. However, the present invention is not limited to this. For example, a sensor that detects an object by transmitting and receiving electromagnetic waves in a frequency band other than the ultrasonic wave may be used.

1 Vehicle Object Detection Device 10 (10a to 10f) Ultrasonic Sensor (Ultrasonic Sensor Unit, Object Detection Sensor)
20 ECU
28 Control circuit (control means, determination means, notification means)
31, 32 buzzer (notification means)
33 (33a-33g) Display (notification means)
U1 Launch wave U1 'Reflected wave

Claims (2)

An object detection sensor that is provided in the periphery of the host vehicle and that receives a reflected wave reflected by an object such as an obstacle that emits a emission wave, and when the predetermined prohibition condition is satisfied, while stopping the object detection sensor, Control means for driving and controlling the object detection sensor to emit the emission wave when the prohibition condition is released, and determination for determining the presence or absence of an object existing around the host vehicle based on transmission and reception of the object detection sensor A vehicle object detection device comprising: a means for notifying the driver when it is determined that there is an object around the vehicle by the determination means;
Equipped with a vehicle speed sensor that detects the vehicle speed of the host vehicle,
When the prohibition condition is canceled , the control means drives and controls the object detection sensor on the condition that the vehicle speed detected by the vehicle speed sensor is lower than a predetermined value, and when the prohibition condition is not canceled. even, based on the vehicle speed detected by the vehicle speed sensor, the vehicle where the vehicle when it is determined that no such unit is stopped, characterized in that it is configured to drive control the object detection sensor Object detection device.   The vehicle object detection device according to claim 1, wherein the prohibition condition includes turning on a parking brake switch indicating that a parking brake provided in the host vehicle is in an operating state.

Images