JPH0511051A - Radar for measuring distance between vehicles - Google Patents

Abstract

PURPOSE:To improve reliability by turning a light emitting part and a light receiving part in the horizontal direction in association with the steering angle of a vehicle, and performing the continuous measurement during the running along a curve. CONSTITUTION:A base frame 26 for holding a laser main body 21 having a light emitting part 19 and a light receiving part 20 is attached to the body of a vehicle. The optical axis in the up and down directions is adjusted with an adjusting screw in the up and down directions. Then, driving is started. When the vehicle body reaches a curved road and a steering wheel is turned, the steering angle is detected 37. An actuator 27 for controlling the right and left directions is driven with this signal by the corresponding value. The main body 21 is turned with a ball bearing 29 as a supporting point through a ball joint member 24 by the movement of an arm 28 in the axial direction. The main body is automatically adjusted so that the optical, axis is directed to the vehicle body. Therefore, in the radar by which the distance to the target vehicle is obtained by the measurement of the time from the projection of the laser light on the target vehicle to the reception of the reflected light, the distance to the preceding vehicles can be accurately obtained all the time.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an inter-vehicle distance radar using a laser beam, and more particularly, to make the emission direction of the laser beam and the traveling direction of the vehicle coincide with each other as much as possible to enhance the reliability of measurement. The present invention relates to the inter-vehicle distance radar.

[0002]

2. Description of the Related Art A laser beam is radiated forward from the front of a vehicle body, and the distance between the vehicle body and the preceding vehicle body is based on the time until the emitted laser beam is reflected by the preceding vehicle and received. As a conventional inter-vehicle distance radar for measuring, there is, for example, a structure as shown in FIG.

That is, in FIG. 1, reference numeral 1 denotes a laser radar main body having a laser emitting section 2 and a laser receiving section 3, and both left and right side surfaces of the laser main body 1 are attached to movable brackets 4 and 5. It is pivotally supported by axial screws 6 and 7 in the horizontal direction. The one bracket 4 is supported by a mounting bracket 9 via a vertical support shaft 8, and the other bracket 5 is connected by a left and right optical axis fine adjusting screw 10 positioned in the front-rear horizontal direction. Reference numeral 11 denotes an arm fixed to an upper part of the radar main body 1, that is, an upper part than the shaft screw 7.
1 and an upright piece 12 upright from the front side of the mounting bracket 9.
The upper and lower optical axis fine adjustment screws 13 which are positioned in the front-rear horizontal direction are connected between the and. Reference numeral 14 denotes a mounting hole 1 provided in the mounting bracket 9 and the movable brackets 4 and 5.
5 is a mounting screw for fixing to a vehicle body (not shown) through 5.

In the radar device thus constructed, after the radar device is temporarily fixed to the vehicle body, the optical axis of the laser beam emitted from the radar device is adjusted to a predetermined position. However, when adjusting the optical axis of the radar device in the left-right direction, the left-right optical axis fine adjustment screw 1
Movable bracket 4 integrated with radar body 1 by turning 0
Since and 5 rotate in the front-back direction with the support shaft 8 as a fulcrum,
As a result, the laser optical axis is finely adjusted in the left-right direction. Further, when the optical axis is to be adjusted up and down, the radar main body 1 fixed to the arm 11 is finely rotated about the axis screws 7 and 6 by rotating the vertical optical axis fine adjustment screw 13. The optical axis of the radar main body 1 can be adjusted in the vertical direction.

[0005]

As described above, since the optical axis of the conventional radar can be adjusted in the vertical direction or the horizontal direction, when the radar is installed in the vehicle body, the optical axis adjustment is performed. Although the optical axis can be set to point to a predetermined position by means, the adjusted radar is fixed to the vehicle body, and therefore the optical axis cannot be displaced when the vehicle body is running.

That is, as shown in FIG. 3, when the vehicle is approaching a curve and the optical axis is constant, the laser beam deviates from the preceding vehicle, which causes an accurate measurement of the distance between the preceding vehicle and the preceding vehicle. There was a problem that it could not be caught or the driver feels uncomfortable.

[0007]

SUMMARY OF THE INVENTION The present invention has been made in view of the above conventional problems. When a driver operates a steering wheel, the steering wheel operation angle is detected and based on the detection signal. The laser radar main body can be automatically driven so that the optical axis of the laser radar main body coincides with the traveling direction of the vehicle, and the distance between the preceding vehicle and the preceding vehicle can always be accurately detected. An object is to provide an inter-vehicle distance measuring radar.

[0008]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described below in detail with reference to the embodiments shown in the drawings.

Reference numeral 21 is a laser radar main body, and this radar main body 21 is the same as that described in the conventional example.
9 and a laser light receiving unit 20. As shown in FIGS. 4 and 5, respective mounting plates 22 and 23 are fixed to the left and right sides of the radar main body 21, and these mounting plates 22 and 23 further include
The ball joint members 24 and 25 are fixed.
Reference numeral 26 is a base frame directly fixed to the vehicle body.
A left-right direction control actuator 27 is supported by 6. A ball bearing 29 is fixed to the one mounting plate 23 below the mounting position of the ball joint member 25, and the ball 30 fitted in the ball bearing 29 is supported by the base frame 26. There is something.

A ball 31 fitted in the ball joint member 24 is fixed to the tip of the arm 28 consumed by the actuator 27, and an upright portion 26 'standing upright on the front portion of the base frame 26 is fixed. The upper and lower adjusting screws 32 are meshed with each other, and a ball 33 fitted in the ball joint member 25 is fixed to the tip of the screw 32.

The above is the embodiment of the structure on the laser radar side, but the steering shaft 34 in the other vehicle compartment is provided with a gear 35 fixed to the steering shaft 34 and a gear transmission mechanism 36 meshed with the gear 35. A steering angle detector 37 that interlocks with each other is provided.

Next, the operation will be described. The base frame 26 holding the radar main body 21 is attached to the front portion of the vehicle body, and the adjusting screw 32 is used to adjust the vertical optical axis direction of the radar main body 21 before operation. To start. When the vehicle body approaches a curve while driving, the steering is rotated in response to the curve. The steering rotation angle, that is, the operation angle is detected by the detector 37, and the left-right direction control actuator 27 is detected by this detection signal. Is driven by a value corresponding to the steering angle. When the actuator 27 drives and the arm 28 moves in the axial direction, the radar main body 21 causes the ball bearing 2 to move through the ball joint member 24.
As a result, the radar main body 21 is rotated about the fulcrum 9 as a fulcrum, and as a result, the optical axis of the radar main body 21 is adjusted in the left-right direction, and the optical axis is automatically adjusted so as to face the preceding vehicle body.

That is, the driver operates the steering wheel to enter the curved road. The steering angle γ of the steering wheel and the turning angle β of the front wheels are structurally predetermined as the steering angle ratio K. Therefore, by attaching the steering angle detector 37 from the rotating shaft 34 of the steering wheel via the gear device 36. , The cutting angle β of the front wheels can be calculated.

In a truck or the like, when turning at the same speed even on the same curved road depending on the weight of the load, the cutting angle β of the front wheels and the direction θ of the vehicle are different. The optical axis direction α of the laser radar main body 21 can be controlled.

In the above embodiment, the vertical optical axis direction adjustment of the radar main body 21 can be performed manually, and the horizontal optical axis adjustment can be automatically adjusted in accordance with the steering angle of the steering wheel. In order to automatically adjust the optical axis direction in the vertical direction as well, a vertical control actuator 38 is provided on the base frame 26 as shown in FIG. 7, and the tip of the arm 39 expended from the actuator 38 is attached to the ball joint member. The ball 33 fitted in 25 is mounted. The vehicle body is equipped with a load supporting switch or a sensor such as a well-known front and rear inclination detector, and the actuator 38 is driven based on the inclination signal output according to the inclination of the vehicle body. It is possible to automatically correct the vertical optical axis of the radar main body 21 in accordance with the inclination of, or the gradient of the road.

[0016]

As described above, according to the present invention, a laser light signal is projected toward a target vehicle, a reflected light signal of the signal at the target vehicle is received, and the reflected light signal is emitted from the time of projection of the signal. In an inter-vehicle distance measuring radar in which a distance to a target vehicle is known by measuring a time until a signal is received, a light emitting unit 19 that projects the laser light signal and a light receiving unit 20 that receives the reflected light signal. Is an inter-vehicle distance measuring radar in which the vehicle body is supported so as to rotate in the horizontal direction in conjunction with the steering angle of the vehicle. Therefore, according to this, even when the traveling vehicle body is traveling on a curve, There is an effect that the inter-vehicle distance to the preceding vehicle can always be accurately captured, and a highly reliable inter-vehicle distance measuring radar can be provided.

[Brief description of drawings]

FIG. 1 is an explanatory view showing a conventional example.

FIG. 2 is a partial structural view of a conventional example.

FIG. 3 is an explanatory diagram of a laser beam on a curve.

FIG. 4 is a perspective view showing an embodiment of an inter-vehicle distance measuring radar according to the present invention.

FIG. 5 is a partial perspective view of the present embodiment.

FIG. 6 is an explanatory diagram of a configuration of a steering unit according to the present embodiment.

FIG. 7 is a perspective view showing another embodiment of this embodiment.

[Explanation of symbols]

19 ... Laser emitting part 20 ... Laser receiving part 21 ... Radar main body 22 ... Mounting plate 23 ... Mounting plate 24 ... Ball joint member 25 ... Ball joint member 26 ... Base frame 27 ... Left / right direction control actuator 28 ... Arm 29 ... Ball bearing 30 ... Ball 31 ... Ball 32 ... Vertical adjustment screw 33 ... Ball 34 ... Steering shaft 35 ... Gear 36 ... Gear transmission mechanism 37 ... Steering angle detector 38 ... Vertical direction control actuator 39 ... Arm

Claims (1)

Claim: What is claimed is: 1. A laser light signal is projected toward a target vehicle, a reflected light signal of the signal from the target vehicle is received, and the signal is projected until the reflected light signal is received. In an inter-vehicle distance measuring radar in which the distance to a target vehicle is known by measuring the time of 1), a light emitting unit (19) that projects the laser light signal and a light receiving unit (20) that receives the reflected light signal are provided. An inter-vehicle distance measuring radar characterized in that it is supported on a vehicle body so as to rotate horizontally in accordance with a steering angle of the vehicle.