JP2003194939A - Obstacle detector - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an obstacle detector which prevents an unnecessary warning from being issued by erroneously judging the ground to be an obstacle when a vehicle is tilted due to the ground or a load or when a vehicle height as a whole is low due to the load. <P>SOLUTION: An obstacle detector ECU 40 inputs inclination information θ on the vehicle on the basis of a vehicle inclination signal, it judges whether the information is within a prescribed time (or within a prescribed running distance) from an inclination change, and, when Yes, a threshold value Vth is increased in order to reduce a detecting area according to an angle of inclination θ. Whether the vehicle height is lowered or not is judged on the basis of a vehicle height signal 51, and, when it is lowered, the threshold value Vth is increased in order to reduce the detecting area according to the vehicle height. Then, ultrasonic waves are burst-transmitted from an ultrasonic sonar 1 and an ultrasonic sonar 2 in a time-sharing manner, a reflected- wave signal 41 and a reflected-wave signal 42 from the ultrasonic sonars are received, the reflected-wave signal whose reflected-wave signal level is the threshold value Vth or more is extracted. Whether the time until its reception from its transmission is the threshold value or less is judged, and, when Yes, a buzzer driving signal 21 is made active. <P>COPYRIGHT: (C)2003,JPO

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an obstacle detecting device for detecting an obstacle in a vehicle and issuing an alarm.

[0002]

2. Description of the Related Art Generally, in this type of obstacle detection device,
As an obstacle detection sensor, ultrasonic sensors installed at appropriate positions such as bumpers in the front and rear of the vehicle transmit ultrasonic burst waves and measure the time until the reflected waves from the obstacle are received. It is configured to issue an alarm when the distance from the sensor to the obstacle is shorter than a predetermined distance. For alarms, the detected position is displayed and
Warning indicator light / buzzer, for example, 20 cm to 50 cm
Blinking / intermittent sound in the range of, and continuous lighting / continuous sound in the range of 20 cm or less.

Further, in order to detect only the primary reflected wave from the obstacle, a reflected wave signal having a reflected wave signal level equal to or higher than a predetermined level Vth is extracted, and a distance obtained by this reflected wave signal is less than a predetermined distance Dth. It is configured to give an alarm when it is short. Also, in order to prevent the ground from being erroneously detected as an obstacle, the ultrasonic waves to be transmitted are made to have horizontal directivity so that the obstacle detection area becomes a teardrop in the horizontal direction.

[0004]

However, in the conventional obstacle detection device, the obstacle detection area is made to have a teardrop shape in the horizontal direction, and the reflected wave signal level is equal to or higher than the predetermined level Vth. When the distance extracted by this reflected wave signal is shorter than the predetermined distance Dth, an alarm is uniquely issued. Therefore, when the vehicle leans on the ground or luggage, or when the entire vehicle height due to luggage is low, There is a problem that it is misjudged as an obstacle and an unnecessary alarm is issued.

In view of the above-mentioned problems of the prior art, the present invention can prevent an obstacle from being detected when the vehicle is leaning on the ground or luggage so as to prevent the ground from being erroneously judged as an obstacle. The purpose is to provide a device. Also,
In view of the problems of the conventional example described above, the present invention provides an obstacle detection device capable of preventing the ground from being erroneously determined as an obstacle and issuing an unnecessary alarm when the entire vehicle height is low due to luggage. With the goal.

[0006]

In order to achieve the above object, the present invention is to reduce the obstacle detection area when the vehicle is leaning or when the vehicle height is low. With the above configuration, it is possible to prevent the ground from being erroneously determined to be an obstacle and issuing an unnecessary alarm when the vehicle is leaning on the ground or luggage or when the entire vehicle height is low due to luggage.

[0007]

BEST MODE FOR CARRYING OUT THE INVENTION Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 is an explanatory view showing an arrangement position of an ultrasonic sonar of an embodiment of an obstacle detecting device according to the present invention, and FIG. 2 is a block diagram showing an embodiment of an obstacle detecting device according to the present invention. 3 is a flowchart for explaining the obstacle detection process.

As an example, FIG. 1 shows that ultrasonic sonars 1 and 2 as obstacle detection sensors are installed on the left and right sides of a bumper behind the vehicle, and the ultrasonic sonars 1 and 2 are at the center as shown in FIG. It is star-connected to an obstacle detection ECU (electronic control unit) 40 which is a control device. Obstacle detection E
The CU 40 controls the time division and burst transmission of the ultrasonic waves of the ultrasonic sonars 1 and 2, and also receives the reflected wave signals 41 and 42 from the obstacle received by the ultrasonic sonars 1 and 2, the shift position signal 31, and the vehicle inclination. Signal 11, vehicle height signal 5
Based on 1, it is determined whether or not to issue an alarm. When the alarm is issued, the buzzer drive signal 21 is applied to the buzzer 80.

As shown in FIG. 3, the obstacle detection ECU 40 enters the obstacle detection mode when the vehicle shift position signal 31 is in the R range and the vehicle speed is, for example, 10 km / h or less (step S1). Here, in this obstacle detection, the time until the reflected wave signal whose level is equal to or higher than the threshold value Vth is extracted and the reflected wave signal is received after transmitting the ultrasonic wave (= distance to the obstacle) If is less than or equal to the threshold value, an alarm is issued. First, vehicle inclination information θ is input by the vehicle inclination signal 11 (step S2), and then it is determined whether or not the inclination has changed within a predetermined time (or within a predetermined traveling distance) (step S3). Then, in the case of Yes, the detection area is corrected according to the inclination angle θ (corrected to the insensitive side)
In order to do so, the threshold value Vth is increased (step S4).

Next, it is judged whether or not the vehicle height is lowered by the vehicle height signal 51 (step S5), and if it is lowered, the detection area is corrected according to the vehicle height (corrected to the insensitive side).
In order to do so, the threshold value Vth is increased (step S6). Next, ultrasonic waves are burst-transmitted from the ultrasonic sonars 1 and 2 in a time division manner, and reflected wave signals 41 and 4 from the ultrasonic sonars 1 and 2 are transmitted.
2 is received (step S7), the reflected wave signal whose reflected wave signal level is equal to or higher than the threshold value Vth is extracted, and it is determined whether the time from the time of transmission to the time of reception (= distance to an obstacle) is equal to or less than the threshold value. (Step S8), if Yes, the buzzer drive signal 2
1 is activated (step S9).

A more detailed description will be given with reference to FIGS. First, as shown in FIG. 4, in a horizontal state in which the vehicle V is not tilted and the vehicle height is in a normal state, the obstacle detection area A has a teardrop shape in the horizontal direction and a horizontal ground G.
Is set not to detect as an obstacle. In this setting state, as shown in FIG. 5, the vehicle V retreats on the ground G1 that has risen in the forward direction by an angle θ, and when a horizontal ground G exists behind the ground G1, this The false ground G is erroneously detected as an obstacle. Therefore, when the vehicle is retreating on the ground G1 which is raised by the angle θ in the front direction,
By increasing the threshold value Vth and decreasing the detection area A as shown in (4), it is possible to prevent the horizontal ground G from being erroneously detected as an obstacle.

Further, as shown in FIG. 7, when the entire vehicle height is low due to luggage, the ground G is erroneously detected as an obstacle when the obstacle detection area A is in the initial state. Therefore, when the vehicle height is decreasing, the threshold value Vth is increased and the detection area A is decreased as shown in FIG. 8 to prevent the ground G from being erroneously detected as an obstacle.

In the above embodiment, the case of detecting the rear side has been described, but the present invention can be applied to the case of detecting the front side. The obstacle detection sensor is not limited to the ultrasonic sonars 1 and 2. Further, as the tilt information, instead of the tilt sensor, tilt information obtained from an acceleration sensor or map information of the navigation system may be used.

As described above, according to the present invention, the obstacle detection area is made small when the vehicle is leaning or when the vehicle height is low. Therefore, the vehicle leans on the ground or luggage. In this case, or when the entire vehicle height is low due to luggage, it is possible to prevent the ground from being erroneously determined to be an obstacle and to issue an unnecessary alarm.

[Brief description of drawings]

FIG. 1 is an explanatory view showing an arrangement position of an ultrasonic sonar in an embodiment of an obstacle detection device according to the present invention.

FIG. 2 is a block diagram showing an embodiment of an obstacle detection device according to the present invention.

FIG. 3 is a flowchart illustrating an obstacle detection process.

FIG. 4 is an explanatory diagram showing a case where the vehicle is horizontal and an initial obstacle detection area.

FIG. 5 is an explanatory diagram showing a case where the vehicle is tilted and an initial obstacle detection area.

FIG. 6 is an explanatory diagram showing a case where the vehicle is tilted and a corrected obstacle detection area.

FIG. 7 is an explanatory diagram showing an obstacle detection area when the vehicle height is low and in the initial stage.

FIG. 8 is an explanatory diagram showing a case where the vehicle height is low and a corrected obstacle detection area.

[Explanation of symbols]

1, 2 ultrasonic sonar 11 Vehicle tilt signal 31 Shift position signal 40 Obstacle detection ECU (electronic control unit) 41, 42 Reflected wave signal from obstacle 51 vehicle height signal

─────────────────────────────────────────────────── ─── Continuation of front page (51) Int.Cl. ⁷ Identification code FI theme code (reference) B60R 21/00 626 B60R 21/00 626B G01S 15/10 G01S 15/10 G08G 1/16 G08G 1/16 C F-term (reference) 5H180 AA01 CC11 CC27 LL01 LL02 LL04 LL07 LL11 5J083 AA02 AB13 AC17 AC29 AD04 AE10 AF09 AG07 BA01 BE20 CA01

Claims (4)

[Claims] 1. An obstacle detection sensor for detecting an obstacle in an obstacle detection area in a predetermined horizontal range of a vehicle, an inclination detection unit for detecting an inclination of the vehicle, and an inclination of the vehicle by the inclination detection unit. And a means for detecting an obstacle in the obstacle detection area detected by the obstacle detection sensor by reducing the obstacle detection area. 2. An obstacle detection sensor for detecting an obstacle in an obstacle detection area in a predetermined horizontal range of a vehicle, a vehicle height detection means for detecting a vehicle height of the vehicle, and the vehicle height detection means for detecting the vehicle height. When it is detected that the vehicle height is low, the obstacle detection area is reduced and means for detecting an obstacle in the obstacle detection area detected by the obstacle detection sensor is provided. . 3. An obstacle detection sensor for detecting an obstacle in an obstacle detection area in a predetermined horizontal range of a vehicle, an inclination detecting means for detecting an inclination of the vehicle, and a vehicle for detecting a vehicle height of the vehicle. When the inclination of the vehicle is detected by the high detection means and the inclination detection means, or when the vehicle height is detected by the vehicle height detection means, the obstacle detection area is reduced to reduce the obstacle. An obstacle detection device comprising means for detecting an obstacle in the obstacle detection area detected by the object detection sensor. 4. The obstacle according to claim 1, wherein when the obstacle detection area is reduced, a threshold value of a reflected wave signal level for determining an obstacle is increased. Object detection device.