JP2001228248A - Rangefinder for two-wheeled vehicle and its data correction method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a rangefinder for two-wheeled vehicles which can correctly measure with a measurement error specific to two-wheeled vehicles (caused by a steering angle αor a tilt angle β) corrected. SOLUTION: There are provided a steering angle-detecting part 13 for detecting the steering angle α (including a direction), a tilt-detecting means 14 for detecting the tilt angle β(including a direction), and processing means (a control part 12 and a judging part 15) for rotating to convert and correct measured position data to relatively rotate a reference coordinate of the position data by the detected angles in directions opposite to the directions of the angles.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a ranging device (radar device) for a vehicle used for monitoring an obstacle ahead, following a preceding vehicle, or monitoring an inter-vehicle distance, and more particularly to a ranging device for a motorcycle. .

[0002]

2. Description of the Related Art Various types of distance measuring devices (radar devices) for monitoring a forward obstacle in a vehicle and controlling the following movement have been developed in various types, such as a radio wave type or a laser type. It has been put into practical use and is standard on some models. This means that waves such as radio waves and laser light are scanned and irradiated at least in the horizontal direction (lateral direction) on an object in a predetermined area in front of the vehicle, and the waveform of the reflected wave and the time until reception are obtained. This device obtains position data (at least position data in the traveling direction and the lateral direction) of the target object with respect to the own vehicle, and further obtains the size (for example, lateral width) and speed of the target object as needed. By the way, this type of device practically used up to now is almost all for four-wheel (or more) vehicles, and is developed and designed on the assumption that it is mounted on the body of such a vehicle. .

[0003]

However, in the future, there is a high possibility that the mounting of such a distance measuring device will increase in the field of motorcycles from the viewpoint of improving safety or improving commercial value. . In the case of a two-wheeled vehicle, when traveling on a curved portion of the road, the front wheel side (front half) of the vehicle is inclined with respect to the traveling direction by an amount corresponding to the steering angle of the front wheel, and furthermore, the entire vehicle body is on the road surface. It has the feature of inclining inside the curved part with respect to the direction perpendicular to
Even if the conventional ranging device for a four-wheeled vehicle is simply mounted, there is a problem that accurate measurement becomes impossible due to such a measurement error due to such inclination.

[0004] That is, in a four-wheeled vehicle, except for the influence of a suspension or the like, the entire vehicle body to which the distance measuring device is attached basically maintains a constant positional relationship with the traveling direction and the road surface. If the reference line (the center line of the detection area for scanning and irradiating radio waves or laser light and is generally called an optical axis) is attached to the front of the vehicle in the traveling direction, this reference line will always be Is maintained in the traveling direction of the vehicle, and in the curved portion of the road, the vehicle always faces the tangent direction of the road (the traveling direction of the vehicle).
For this reason, in a conventional distance measuring device designed on the assumption that the vehicle is mounted on such a four-wheeled vehicle, the object (a preceding vehicle or an obstacle) is assumed on the premise of such a running direction and a certain positional relationship with respect to a road surface. ) And the vehicle's positional relationship (ie,
Position data). That is, for example, the direction of the reference line of the distance measuring device itself coincides with the traveling direction of the vehicle (hereinafter, referred to as the front-rear direction or the Y direction), and the basic scanning direction perpendicular to this direction is parallel to the road surface. (Hereinafter referred to as the left-right direction or the X direction in some cases), and processing of the measurement data is performed.

However, as shown in FIG. 4A, a two-wheeled vehicle has a characteristic that it travels along a curved portion of a road (the radius of curvature is R and the center of curvature is 3 in the figure) by steering. Rear wheel side 1 that constitutes the latter half of the body
The (non-steered wheel side) faces the tangential direction of the road, and the front wheel side 2 (steered wheel side) constituting the front half of the vehicle body is inclined inwardly by a steering angle from the tangential direction by the steering angle. . Then, as shown in FIG. 4B, for example, when the distance measuring device 4 is mounted on the center axis 2a of the front wheel side 2, the reference line of the distance measuring device 4 (in this case, the center axis 2a Match)
Is inclined with respect to the center axis 1a of the rear wheel side 1 (that is, the Y axis in the Y direction) by the steering angle α, and this inclination causes a measurement error. For example, the appropriate lateral azimuth data (angle data constituting the position data in the polar coordinate system on the XY plane) of the object 5 in FIG.
Despite being θ + α with respect to the axis, processing means of distance measuring device 4 (or processing means connected to distance measuring device 4)
Then, θ based on the central axis 2a is actually recognized as the azimuth data, and an error is caused by the angle α. According to the calculation by the inventor, the wheel base is 1.495.
m, for example, when traveling on a curved part having a radius of curvature of 350 m, the steering angle α is 0.245 degrees,
Due to this, the measurement position error of the object 100 m ahead is 4
2 cm. By the way, the current ranging device for four-wheeled vehicles is a reflector of the preceding vehicle 100 m away (with a width of 15 to
(About 30 cm) is operated with a recognizable resolution, so that this error is a size that cannot be ignored.

In a motorcycle, as shown in FIG. 4 (c), when traveling on a curved portion, a direction perpendicular to the road surface 6 (hereinafter referred to as a vertical direction or Z (Referred to as a direction), the vehicle bodies 1 and 2 are tilted toward the center of curvature, but this inclination angle β also causes a measurement error. That is, the processing means of the distance measuring device 4 (or the processing means connected to the distance measuring device 4) actually performs the basic scanning inclined by the angle β with respect to the appropriate X direction (the direction parallel to the road surface 6). Since the direction X ′ is recognized as the X direction, for example, the measurement interval in the X direction is CO
An error occurs that is reduced by the ratio of S (β). Incidentally, according to the calculation of the inventor, the foil base is 1.49.
In the case of a 5 m two-wheeled vehicle, for example, when traveling at a speed of 80 km / h on a curved portion having a radius of curvature of 350 m, the inclination angle β becomes 8.19 degrees as an example, and as a result, the measurement interval in the lateral direction becomes zero. .99 times. SUMMARY OF THE INVENTION It is an object of the present invention to provide a ranging device for a motorcycle in which such a measurement error peculiar to the motorcycle is corrected and accurate measurement is possible, and a data correction method therefor.

[0007]

A distance measuring device for a motorcycle according to the present invention is installed on a steered wheel side of a motorcycle, scans and irradiates a detection area in front of the motorcycle with a reflected wave of the wave. A two-wheeled distance measuring device that includes a distance measuring unit that receives and generates at least position data of an object in the detection area based on the reflected wave; a steering angle detecting unit that detects a steering angle and a steering direction of the two-wheeled vehicle; ,
A steering for correcting the position data by rotating and converting the position data so that the reference coordinates of the position data are relatively rotated by the detected steering angle in the direction opposite to the steering direction detected by the steering angle detection means. And an angle correcting means. According to the present invention, the above-described measurement error caused by the steering angle α is canceled by the data correction of the steering angle correcting means.
For this reason, a highly accurate two-wheeled vehicle distance measuring device having no measuring error due to the steering angle α can be realized even though the distance measuring unit is installed on the steered wheel side of the two-wheeled vehicle. Note that the measurement error due to the steering angle α described above is such that the reference coordinate X′Y ′ recognized by the distance measuring device and the appropriate reference coordinate XY are shifted by the steering angle α as shown in FIG. Therefore, the position data before correction obtained by the wave irradiation is rotationally converted by the steering angle α (for example, FIG. 1).
(Α) is added (or subtracted) to the azimuth data θ1 and θ2 in (b), and the calculation result is used as corrected azimuth data.)
The correction can be made by performing the processing.

Here, the "distance measuring unit" is a part corresponding to a detection head of the distance measuring device, and scans and irradiates a wave such as an electromagnetic wave (laser light or radio wave) or an ultrasonic wave in front of the motorcycle. And a configuration for receiving a reflected wave of the irradiated wave (for example, a laser light source or an optical system for irradiating and receiving a laser beam). The scanning may be performed only on the transmission side, but may be performed on the reception side for improving reception efficiency. The scanning may be performed in at least the horizontal direction (X direction) as a basic scanning direction (a one-dimensional scanning method only in the horizontal direction may be used) in order to measure the position and size of the object in the horizontal direction. A two-dimensional scanning method in which scanning is also performed in the (Z direction) is preferable. In the case of the two-dimensional scanning method, the position data of the object in the vertical direction (that is, the height direction) is also obtained, and for example, it is possible to reliably determine whether the preceding vehicle is a truck or an ordinary car. The "steering angle detecting means" can be realized by an angle detecting means such as a rotary encoder and a potentiometer. Further, the "steering angle correction means" can be realized by an arithmetic processing means including an arithmetic circuit such as a microcomputer. Also,
“Steering wheel side” means a portion (usually, the first half of a two-wheeled vehicle) that rotates together with the steered wheels (normally, the front wheels) in association with steering (turning).

In a preferred aspect of the present invention, the steering angle detecting means and the steering angle correcting means described above are provided.
Inclination detecting means for detecting the inclination angle and the inclination direction of the motorcycle from a direction perpendicular to the road surface, and reference coordinates of the position data by the detected inclination angle in a direction opposite to the inclination direction detected by the inclination detection means. And a tilt correcting means for correcting the position data by rotationally converting the position data so that the position data is relatively rotated. With such a configuration, the above-described measurement error due to the inclination angle β is canceled by the data correction of the inclination correction means. Therefore, despite the configuration in which the ranging unit is installed on the steered wheel side of the motorcycle, there is no measurement error due to the steering angle α, and furthermore, an extremely high precision ranging device for motorcycles that has no measurement error due to the inclination angle β is realized. it can. In addition, the measurement error due to the above-mentioned inclination angle β also indicates that the reference coordinate X′Z ′ recognized by the distance measuring device and the appropriate reference coordinate XZ are as shown in FIG. 1C or FIG. Since it is based on the displacement by the tilt angle β, the position data before correction obtained by the wave irradiation is rotationally and rotationally converted by the tilt angle β (for example, in the case of the one-dimensional scanning method, FIG. The horizontal position data L ′ in 1 (c) is divided by COS (α), and the calculation result L is used as corrected horizontal position data). Here, the "tilt detection means" can be realized by an angle detection sensor such as a gyro. The "tilt correction means" can be realized by an arithmetic processing means including an arithmetic circuit such as a microcomputer.

Another distance measuring apparatus for a motorcycle according to the present invention scans and radiates a wave from a two-wheeled vehicle to a detection area in front of the two-wheeled vehicle, and based on a reflected wave of the wave, at least an object in the detection area. In a distance measuring apparatus for a motorcycle that generates position data, an inclination detecting unit that detects an inclination angle and an inclination direction of the motorcycle from a direction perpendicular to a road surface,
Tilt correction for correcting the position data by rotating and converting the position data so that the reference coordinates of the position data are relatively rotated by the detected tilt angle in the direction opposite to the tilt direction detected by the tilt detection means. Means. With such a configuration, as described above, the measurement error due to the inclination angle β is canceled by the data correction of the inclination correction means. For this reason, a high-precision distance measuring device for a motorcycle having no measurement error due to the inclination angle β can be realized. In this case, the distance measuring unit may be installed on the steered wheel side of the motorcycle or may be installed on the non-steered wheel side. In any case, if the conventional configuration is used, at least a measurement error due to the inclination angle β occurs. According to the present invention, this error is eliminated.

According to the data correcting method of the distance measuring apparatus for a motorcycle according to the present invention, a wave is scanned at a predetermined portion of the motorcycle and is irradiated to a detection area in front of the motorcycle to receive a reflected wave of the wave. A distance measuring device for a two-wheeled vehicle including a distance measuring unit and generating at least position data of an object in the detection area based on the reflected wave, wherein the inclination of the predetermined portion with respect to a traveling direction of the two-wheeled vehicle or a direction perpendicular to a road surface. A data correction method for correcting an error of the position data caused by the position data, so that the reference coordinates of the position data are relatively rotated by the inclination angle in a direction opposite to the inclination. The error is corrected by performing a rotational movement conversion on the reference coordinates and correcting it. According to the configuration employing such a data correction method, the measurement error due to the inclination of the predetermined portion is corrected irrespective of the predetermined portion (that is, the installation position of the distance measuring unit), and the accuracy of the distance measuring device for a motorcycle is corrected. Improvement can be realized. That is, the motorcycle has a feature that it travels on a curved portion while partially or entirely inclining with respect to the traveling direction and the road surface as described above. Due to this feature, the motorcycle has at least the inclination angle as described above. β (and steering angle α)
Causes a measurement error due to where the predetermined part is selected. However, such a measurement error is based on the fact that the reference coordinates recognized by the apparatus are shifted in the tilt direction by the amount of the tilt with respect to the appropriate coordinates. Therefore, if the position data is rotationally transformed and corrected so as to correct the rotational displacement of the reference coordinates, the correct position data measured based on the appropriate reference coordinates is eventually obtained. All errors can be corrected.

The above-mentioned correction processing is executed by arithmetic processing means (for example, a microcomputer) in a unit generally called a distance measuring device (in a unit separate from the unit on the vehicle side). Not limited to
For example, it may be executed by an arithmetic processing unit in a vehicle-side control unit (for example, a control unit that controls an engine system, a transmission, a brake system, or the like) that performs follow-up traveling control or the like based on the measurement result of the distance measuring device. Good. Further, the data (the data of the inclination angle β and the steering angle α) for the correction processing is not necessarily based on the output of the sensor that directly detects them. For example, the curvature R of a currently traveling road is estimated from the arrangement shape of a roadside reflector (a reflector regularly arranged on a roadside zone such as an expressway) recognized based on the measurement result of the distance measuring device, The data of the inclination angle β and the steering angle α can be estimated and used from the curvature R and the traveling speed. It should be noted that the inclination angle β of the motorcycle cannot be uniquely determined only by the curvature R and the traveling speed (it cannot be accurately estimated unless the position of the center of gravity based on the posture of the occupant is also known). Assuming that the posture and the like are general, the estimation calculation can be performed with a certain reliability.

[0013]

An embodiment of the present invention will be described below with reference to the drawings. First, a system configuration of a two-wheeled vehicle including the distance measuring device of the present embodiment will be described with reference to FIG. This system includes a distance measuring unit 11, a control unit 12, a steering angle detecting unit 13, a vehicle inclination detecting unit 14, a determining unit 15
, A vehicle-side controller 16, a vehicle-side device 17, and a road curvature estimator 18. Among them, the distance measuring unit 11, the control unit 12, the steering angle detecting unit 13, the vehicle inclination detecting unit 14, the determining unit 15, and the road curvature estimating unit 18 constitute a distance measuring device of the present embodiment. In addition, for example, the distance measuring unit 11, the control unit 12, the determining unit 15, and the road curvature estimating unit 18 may be provided in, for example, a common unit as a main configuration of the distance measuring device. Is provided in a predetermined portion (for example, a steered wheel side of a motorcycle) and the other is provided in another portion (for example, a non-steered wheel side of a motorcycle) as a separate unit. The arrangement | positioning may be sufficient. Further, the control unit 12, the determination unit 15, and the road curvature estimating unit 18 do not necessarily need to be formed of mutually independent circuits, for example, a common control including one microcomputer (hereinafter, referred to as a microcomputer). It may be configured as a different function of the processing circuit.
In addition, the control unit 12, the determination unit 15, or the road curvature estimation unit 1
The reference numeral 8 does not necessarily need to be configured as a separate and independent circuit for the vehicle-side control unit 16. For example, a common circuit including one microcomputer (hereinafter, referred to as a microcomputer) also functions as the determination unit 15 and the like. Alternatively, there may be a configuration that also functions as the vehicle-side control unit 16.

The distance measuring unit 11 scans and irradiates an electromagnetic wave (such as an infrared laser or a radio wave) in front of the motorcycle and receives a reflected wave of the radiated electromagnetic wave (for example, a laser emission source or a laser beam). Optical system for irradiating and receiving
Or an antenna or an electric circuit for transmitting and receiving radio waves). Scanning may be performed only on the transmitting side,
A configuration may also be performed on the receiving side to improve reception efficiency. The scanning may be performed in at least the horizontal direction (X direction) as a basic scanning direction (a one-dimensional scanning method only in the horizontal direction may be used) in order to measure the position and size of the object in the horizontal direction. A two-dimensional scanning method that performs scanning also in the (Z direction) may be used. In the case of the two-dimensional scanning method, the position data of the object in the vertical direction (that is, the height direction) is also obtained, and for example, it is possible to determine whether the preceding vehicle is a truck or a normal car. The scanning mechanism is, for example, a laser beam emitted from a laser emission source, which is reflected in each direction by a rotating reflecting mirror to irradiate the laser beam, and a laser beam emitted from the laser emission source is moved by a movable optical lens. One that irradiates the laser beam bent in each direction, one that irradiates the laser beam output from the laser emission source by bending it in each direction by a plurality of prisms whose positional relationship is variable, or one that outputs the laser beam (or a radio wave transmission) Of the laser beam (or radio wave) is changed by sequentially switching the laser light source (or antenna) to be used. And scanning by rotating the laser light source (or antenna) itself. Here, a polygon mirror integrating a plurality of mirrors may be used as the reflection mirror.

The distance measuring section 11 may be mounted on a vehicle body on a steered wheel side (normally, a front wheel side) of a two-wheeled vehicle, or may be mounted on a vehicle body on a non-steered wheel side (normally, a rear wheel side). By the way, it is usually difficult to attach to the rear wheel side because there is a high possibility that laser light etc. will be blocked by the front wheel side body, but for example, a windshield fixed to the rear wheel side body is in front of the handlebar In a motorcycle of the type provided, if the distance measuring unit 11 is attached to the windshield, laser light or the like can be irradiated without any problem. And if it can be attached to the vehicle body on the non-steered wheel side (normally, the rear wheel side), the measurement error due to the steering angle described above will not occur.
In the following, in the present embodiment, a description will be given assuming that the distance measuring unit 11 is provided on the steered wheel side (normally, the front wheel side) of the two-wheeled vehicle.

Next, the control unit 12 is realized by a circuit including a microcomputer and a program (software) therefor, for example, and has the following functions. That is, while controlling the distance measuring unit 11 (instructing start and end of electromagnetic wave irradiation, designating a scanning direction, and the like), the distance measuring unit 11 is controlled.
The result of electromagnetic wave transmission / reception (waveform of reflected wave or time until reception, data of irradiation direction, etc.) is read,
Noise removal processing, data correction processing (steering angle correction described later), or grouping processing (for example, in the case of a car,
Since the left and right reflectors are observed as separate objects, processing such as combining them as one vehicle) is performed, and information on the presence or type (or size) and position data of the object is obtained from the read information. (For example, information indicating that an automobile is located 100 m ahead) and outputs the data as distance measurement data.

Next, the steering angle detector 13 determines that the steered wheel side (normally, the front wheel side) of the two-wheeled vehicle is the non-steered wheel side (normally, the rear wheel side).
To detect the degree of rotation (ie, the steering angle) with respect to the steering wheel. Specifically, for example, it is mounted on the non-steered wheel side, and the rotation of the steered wheel side is transmitted to its input shaft. It can be constituted by a rotary encoder, a potentiometer, and the like provided as described above. Further, the vehicle inclination detecting unit 14 is configured to detect the vehicle body of the motorcycle (both on the steered wheel side and on the non-steered wheel side)
Detects how much the vehicle is inclined with respect to a road surface (usually, a horizontal plane) (that is, an inclination angle), and can be specifically realized by a gyro sensor, a yaw rate sensor, or the like. The steering angle detector 13 corresponds to a steering angle detector of the present invention, and the vehicle inclination detector 14 corresponds to a tilt detector of the present invention.

Next, the determination section 15 is realized by a circuit including a microcomputer and a program (software) therefor, for example, and has the following functions.
That is, the information output from the control unit 12, the steering angle detection unit 13, and the vehicle inclination detection unit 14 (the above-described distance measurement data,
Detection data of the steering angle and the inclination angle) and the vehicle-side control unit 1
6 and the information output from the road curvature estimating section 18 (data of the traveling speed of the own vehicle and the curvature of the road), and if necessary, corrects the distance measurement data (inclination correction described later), Such as calculating the preceding vehicle traveling on the same lane, or calculating the positional relationship or relative speed relationship between the own vehicle and other vehicles and obstacles present in the surroundings in a time-series manner, Performs information processing analysis processing. In the case of performing the following travel control (control for automatically accelerating and decelerating and maintaining a predetermined inter-vehicle distance with respect to the preceding vehicle), the vehicle to be followed is determined from the result of the processing analysis processing of the information described above. Then, the sequential acceleration / deceleration amount is determined according to a predetermined reference, and the determination result is sequentially notified to the vehicle control unit 16. Further, when performing a warning control for a collision, the possibility of a collision with a preceding vehicle or an obstacle in front is determined based on a result of the processing analysis processing of the information according to a predetermined standard, and the possibility of the collision is determined. If the default value is exceeded,
Control for outputting a warning by a buzzer sound or the like to the driver (specifically, for example, processing for transmitting a command for that to the vehicle-side control unit 16) is executed.

Incidentally, in the case of a two-wheeled vehicle, there is a characteristic that the vehicle must be tilted against centrifugal force that changes depending on the traveling speed and the curvature to travel while maintaining a balance.
When instructing the automatic acceleration / deceleration in the following cruise control described above, it is preferable to perform a control for outputting a warning by a buzzer sound or the like to the driver in advance. When it is determined from the information of the steering angle detecting unit 13 and the road curvature estimating unit 18 that the vehicle is traveling on a curved portion (that is, a curve), such automatic acceleration / deceleration control is not performed. (Or suppress the acceleration / deceleration amount to a lower level). Therefore, such a control process may be performed in the determination unit 15 or the vehicle-side control unit 16, for example. The control unit 12 and the determination unit 15 correspond to a steering angle correction unit and an inclination correction unit of the present invention.

Next, the vehicle-side control unit 16
A controller (consisting of a control circuit including a microcomputer) for various systems of a vehicle (engine control system, brake control system, shift control system, or alarm system), which may be provided separately for each system, It may be an integrated type (for example, it may be a controller that controls the engine and the transmission as a whole). The vehicle-side control unit 16 has the following functions particularly in the system of the present embodiment. That is, based on a command from the determination unit 15, for example, accelerator control, shift control, brake control, and the like for following travel are performed. When a warning output command for the above-described collision is input from the determination unit 15, a buzzer drive control for actually executing the warning output is performed. And in this case,
A process of sequentially outputting information on the traveling speed of the host vehicle to the control unit 15 is also performed.

Next, the vehicle side equipment section 17
A device such as an engine, a transmission or a brake of a motorcycle, an alarm (buzzer) or a speed sensor, which is operated under the control of the vehicle-side control unit 16, or the vehicle-side control unit 1
6 and sensors for outputting detection data of the traveling speed and the like. Next, the road curvature estimating unit 18 is provided with a sensor (for example, a yaw rate sensor) provided as needed.
For example, it is realized by a circuit including a microcomputer and a program (software) therefor, and has the following functions. That is, it reads information output from the steering angle detection unit 13 and the determination unit 15 (detection data of the steering angle and data relating to the positional relationship of the roadside reflector) and information output from the sensor (for example, a yaw rate sensor). And has a function of calculating or estimating the curvature of the road on which the vehicle is currently traveling and outputting the result. The method of calculating the curvature may be a method of obtaining from the steering angle α and the physical shape of the vehicle wheel base or the like, a method of obtaining from the output of the yaw rate sensor, or a method of obtaining from the positional relationship data of the roadside reflector. . In the case of a road on which a reflector is regularly installed, such as a highway in Japan, the curvature of the road can be calculated quite accurately from the positional relationship data of the reflector.

Next, an example of the operation of the system including the distance measuring apparatus of the present embodiment will be described with reference to the flowchart of FIG.
First, in step S1, the determination unit 15 (or the control unit 12) reads output data (data of the steering angle α and the inclination angle β) of the steering angle detection unit 13 and the vehicle inclination detection unit 14.
Next, in step S2, for example, the control unit 12
It is determined whether or not the distance measuring operation of the distance measuring unit 11 (the operations of steps S4 to S8 to be described later) under the control of 2 has been completed for the entire scanning range, and if completed, the process proceeds to step S9. If so, the process proceeds to step S4.

In steps S4 to S8, the following operations are sequentially performed under the control of the control unit 12. That is, the irradiation direction of the electromagnetic wave such as a laser beam in the distance measurement unit 11 is switched to the next setting (the next irradiation direction in a series of scans) (step S4), and a predetermined electromagnetic wave is emitted from the distance measurement unit 11 (step S4). S5) The distance measuring unit 11 observes the waveform of the reflected wave (step S6), and the control unit 12 calculates and stores the distance from the received waveform to the target object (detected object) such as a preceding vehicle or an obstacle. (Step S7) At that time, the irradiation direction of the electromagnetic wave (that is, the azimuth data of the object) is stored (Step S8). The operations in steps S4 to S8 are sequentially repeated until the determination in step S3 is affirmative. As a result, the transmission / reception result (the waveform of the reflected wave or the time to reception, A series of reading operations of the irradiation direction data) is completed.
That is, in this case, the control unit 12 reads the position information of each object as polar coordinate data (azimuth data and distance data) based on, for example, the center axis 2a (shown in FIG. 1B) on the front wheel side. For example, in the case of the one-dimensional scanning method only in the horizontal direction, one X'Y 'as shown in FIG.
Azimuth data θ1 of each object T1, T2 on the plane
θ2 and distance data L1 and L2 are obtained. In the case of the two-dimensional scanning method, for example, the above data is obtained for a plurality of X'Y 'planes at different positions of the coordinate Z' in the height direction. The direction of the direction data is, for example, as shown in FIG.
In (b), if the direction data to the right of the center axis 2a is a positive value and the direction data to the left is a negative value,
In the following description, it is assumed that the polarity is set as described above (that is, FIG.
The azimuth data θ1 exemplified in (b) is a positive value in this case, and the azimuth data θ2 is a negative value in this case.)

On the other hand, in step S9, in this case, the correction of the error due to the steering angle (the function of the steering angle correction means of the present invention) is executed by the processing of the control unit 12. That is, the steering angle detector 1
3 (in this case, rightward when the steering angle α is a positive value, leftward when the steering angle α is a negative value)
In the opposite direction, the reference data X'Y 'of the position data is relatively rotated by the absolute value of the detected steering angle α, and the position data is adjusted so as to match the appropriate reference coordinate XY. Modify by rotating and converting. Specifically, for example, when the azimuth data θ1 and θ2 of each of the objects T1 and T2 as shown in FIG. 1B are obtained, an operation of adding the steering angle α to these data is performed. In this case, since θ2 is a negative value, the absolute value is subtracted.) Then, the calculation results θ1 + α and θ2 + α are stored as new azimuth data (for example, θ1 = θ1
+ Α). According to the correction of the data (steering angle correction), the corrected azimuth data is temporarily measured based on the appropriate coordinates XY (shown in FIG. 1B) along the center axis 1a on the rear wheel side. Is the same as the azimuth data when.
In other words, the rectangular coordinates that serve as the reference for azimuth data are
This is the same as shifting from X′Y ′ (displaced by the steering angle α) shown in FIG. 1B to the appropriate coordinates XY. For this reason, the above-described measurement error due to the steering angle α is canceled, and the measurement error due to the steering angle α is eliminated even though the distance measuring unit 11 is installed on the steered wheel side of the motorcycle.

In step S10, the position information of each object (in this case, the data after the steering angle correction in step S9) is converted from polar coordinate data to rectangular coordinate data by the processing of the control unit 12 in this case. . For example, FIG.
In the case of the target T1 in (b), SIN (θ1) is the position data in the X direction, and COS (θ1) is the position data in the Y direction. In the case of the two-dimensional scanning method, the position data (X direction, Y direction) of the three-dimensional rectangular coordinate system is thereby obtained.
Direction and Z-direction position data). Next, in step S11, in this case, the control unit 12 sets the distance measurement data (in this case, the position data as the above-described rectangular coordinate data).
(Grouping process). That is, the objects for which the above-described position data is grasped at this time are not necessarily separate objects. For example, a plurality of reflectors of the same automobile are grasped as separate objects. Therefore, for example, among the objects measured by one scan, those whose distances between the respective objects calculated from the respective position data are equal to or less than a predetermined value are integrally treated as the same object. In addition, here, the object detected in the previous scan is associated with the object detected in the current scan (that is, it is determined whether or not the objects are the same based on the width or the moving distance). Then, the objects determined to be the same are associated as the same).

Next, in step S12, the correction of the error due to the tilt angle (the function of the tilt correcting means of the present invention) is executed by the processing of the determination unit 15 in this case. That is, the detected inclination is opposite to the inclination direction detected by the vehicle inclination detection unit 14 (in this case, rightward when the inclination angle β is a positive value, leftward when the inclination angle β is a negative value). The position of each object obtained by the operation up to step S11 so that the reference coordinate X'Z 'of the position data is relatively rotated by the absolute value of the angle β so as to match the proper reference coordinate XZ. Correct the data by rotating and converting it. Specifically, 1
In the case of the dimensional scanning method, for example, when position data L ′ in the X ′ direction of the object T2 as shown in FIG. 1C is obtained, the data L ′ is divided by COS (β). I do. Then, the calculation result L ′ / COS (β) is stored as new horizontal position data L (L = L ′ / CO
S (β)). According to such data correction (tilt correction), the position data L after correction is temporarily measured based on the appropriate coordinates XZ (shown in FIG. 1C) parallel or perpendicular to the road surface. Is equal to the position data. In other words, the rectangular coordinates serving as the reference for the position data are shown in FIG.
This is the same as shifting from X′Z ′ (displaced by the inclination angle β) shown in (c) to the proper coordinates XZ. For this reason, the above-described measurement error due to the inclination angle β is canceled,
The measurement error due to the inclination angle β is eliminated.

The tilt correction is performed as follows in the case of the two-dimensional scanning method. For example, as shown in FIG. 2B, the position data on the coordinate X'Z 'is (X1, Z1).
When the target T3 is measured, new position data (X2, Z2) is obtained by the following equations (1) and (2). X2 = Z1 × SIN (β) + X1 × COS (β) (1) Z2 = Z1 × COS (β) −X1 × SIN (β) (2) Note that the above equations (1) and (2) are This is nothing less than the general formula of rotational movement conversion in two-dimensional coordinates (orthogonal coordinates) by the angle β (conversion of position data by rotating and moving the position by the angle β while maintaining the distance from the origin). Also in this case, the corrected position data (X2, Z2) is equal to the position data when the measurement is temporarily performed with reference to the appropriate coordinates XZ (shown in FIG. 2B) parallel or perpendicular to the road surface. Become. In other words, it is the same as when the orthogonal coordinates serving as the reference of the position data have shifted from X′Z ′ (displaced by the inclination angle β) shown in FIG. 2B to the appropriate coordinates XZ. Therefore, the above-described measurement error due to the inclination angle β is canceled, and the measurement error due to the inclination angle β is eliminated. In addition,
The object T3 whose position data on the coordinates X'Z 'is (X1, Z1) is obtained by scanning in the horizontal direction at a height (height of Z1) indicated by reference numeral SC1 in FIG. The object is measured, and the position in the horizontal direction is determined to be X1.

In the case of the two-dimensional scanning method, the position data in the height direction of the object can be known, and the lateral position caused by the inclination angle β is erroneously recognized (actually, the position of the object having a different lateral position is different). Erroneously recognized as being at the same position in the lateral direction). This is because in the case of the one-dimensional scanning method, the position in the horizontal direction (X direction) and the height direction (Z direction) are actually located on appropriate coordinates, for example, the objects T2 and T4 in FIG. ), The position data in the horizontal direction (X ′ direction) matches on the coordinates at the time of measurement (all in L ′).
In the eleventh grouping process, there is a possibility that the same item is determined. However, in the two-dimensional scanning method, such position data in the height direction of the objects T2 and T4 can also be obtained. Therefore, the position data in the horizontal direction after being corrected by the above-described expression (1) is the object T2. And T4. For this reason, like T2 and T4 in FIG. 1 (c), separate objects that are close in the horizontal direction and different in height (for example, a tall truck running side by side and a tall truck) It is possible to reliably separate and grasp each reflector of a low ordinary car). Therefore, from such a point, it can be said that the two-dimensional scanning method is preferable as the ranging device for a motorcycle.

Next, in step S13, the determination unit 15 or the vehicle-side control unit 16 determines whether the measurement result obtained by the previous scan is
The relative speed of the target (detected object) is calculated by comparing the measurement results obtained by the current scan. Specifically, the target object determined as the same object is moved from the position of T5 (X5, Y5) shown in FIG. 2C to T6 between the previous scan and the current scan, for example.
When it is measured that the movement has been made to the position (X6, Y6), if the measurement time interval Δt (the time interval from the previous scan to the current scan) is used, needless to say, the following equation (3), By (4), the relative speeds Vx and Vy of the object with respect to the own vehicle (Vx is the relative speed in the X direction and Vy is the relative speed in the Y direction) can be obtained. Vx = (X6-X5) ÷ Δt (3) Vy = (Y6-Y5) ÷ Δt (4) Next, in step S14, the determination unit 15 or the vehicle-side control unit 16 determines whether the measured object is Find the distance from the lane. Specifically, first, for example, the own lane 7 as shown in FIG. 2C is obtained from the curvature R estimated by the road curvature estimation unit 18. The own lane 7 is located on the rear wheel side 1 of the own vehicle.
(In this case, a non-steered wheel) is an arc of curvature R in contact with the center axis 1a (that is, the Y axis). Then, an interval D6 between the arc and, for example, the object T6 is obtained. Next, step S15
Then, the determination unit 15 or the vehicle-side control unit 16 determines the preceding vehicle on the own lane. That is, the object provided with the interval provided in step S14 (for example, the interval D6 shown in FIG. 2C) is smaller than a predetermined value, and is determined to be a running vehicle based on the relative speed, the width, and the like. Is determined as the preceding vehicle.

Next, in step S16, when there are a plurality of objects determined as preceding vehicles, the determination unit 15 or the vehicle-side control unit 16 determines the closest one of the objects to be followed (step S16). (The preceding vehicle to be followed), and when there is only one object determined as the preceding vehicle, the object is selected as the following object. In step S17, in this case, the vehicle-side control unit 16 performs an automatic control operation for following the vehicle based on the measurement data or the like of the object to be followed (position data or data of the above-described relative speed). For example, when the distance to the object to be followed is equal to or less than a predetermined value and the relative speed Vy in the front-rear direction of the object to be followed is equal to or less than the predetermined value, a control command for performing deceleration corresponding thereto is transmitted to a brake system, a transmission system, or an engine. Output to the system. Conversely, for example, when the distance to the object to be followed exceeds the predetermined value and the relative velocity Vy in the front-rear direction of the object to be followed exceeds the predetermined value, a control command for performing acceleration according to the predetermined value is transmitted to the brake system. Or to a transmission system or an engine system. When such automatic acceleration / deceleration is performed, as described above, it is preferable that the driver be notified of the fact in advance by an alarm sound, a display lamp, or the like. FIG. 3 shows only the follow-up running control. However, in steps S15 to S17, an obstacle is monitored (for example, a stationary object on the own lane is determined, and a warning is issued to the driver when there is a possibility of collision). ) And / or inter-vehicle distance monitoring (for example, warning the driver when the distance to the preceding vehicle is less than or equal to a predetermined value) is performed instead of or together with the following travel control. obtain.

In the embodiment described above, the aforementioned measurement error due to the steering angle α is canceled by the data correction (steering angle correction) in step S9. After the steering angle correction is performed, data correction (inclination correction) in step S12 is further performed, and the measurement error due to the inclination angle β is also canceled. For this reason, a highly accurate two-wheeled vehicle ranging device that has no measurement error due to the steering angle α and has no measurement error due to the inclination angle β even though the distance measurement unit 11 is installed on the steered wheel side of the motorcycle. it can. And for this,
The above-described follow-up cruise control, obstacle monitoring, or inter-vehicle distance monitoring control based on the measurement result of the distance measuring device can be reliably and accurately realized even in a motorcycle.

The present invention is not limited to the above-described embodiment, and it goes without saying that various aspects and modifications are possible. For example, in the flowchart shown in FIG. 3, the correction of the measurement error due to the steering angle α (steering angle correction) is performed more than the conversion process from the polar coordinates to the rectangular coordinates (step S10) and the data collection process (step S11). Although performed before, it may be performed after these processes. The correction of the measurement error due to the tilt angle β (tilt correction) is performed after the conversion process from the polar coordinates to the rectangular coordinates (step S10) and the data collection process (step S11). You may go before. However, if the correction of the present invention is performed in the state of the polar coordinate data as in step S9, the calculation of the data correction (data correction by rotation / transformation) for the correction is facilitated (that is, the azimuth data is corrected as described above). For example, it is sufficient to simply add the steering angle α, and the calculation of the trigonometric function becomes unnecessary.)

[0033]

The distance measuring device for a motorcycle according to the present invention is installed on the steered wheel side of the motorcycle and scans and irradiates a detection area in front of the motorcycle with a wave to receive the reflected wave of the wave. A distance measuring device for a motorcycle that generates at least position data of an object in the detection area based on the reflected wave; a steering angle detection unit that detects a steering angle and a steering direction of the motorcycle; Steering angle correcting means for converting the position data into a rotational direction and correcting the position data so that the reference coordinates of the position data are relatively rotated by the detected steering angle in the direction opposite to the steering direction detected by the detecting means; Are provided. According to the present invention, the above-described measurement error caused by the steering angle α is canceled by the data correction of the steering angle correcting means. For this reason, a highly accurate two-wheeled vehicle distance measuring device having no measuring error due to the steering angle α can be realized even though the distance measuring unit is installed on the steered wheel side of the two-wheeled vehicle.

According to the data correction method of the distance measuring apparatus for a motorcycle according to the present invention, the motorcycle is installed at a predetermined portion of the motorcycle and scans and irradiates a detection area in front of the motorcycle with a reflected wave of the wave. A distance measuring device for a two-wheeled vehicle including a distance measuring unit and generating at least position data of an object in the detection area based on the reflected wave, wherein the inclination of the predetermined portion with respect to a traveling direction of the two-wheeled vehicle or a direction perpendicular to a road surface. A data correction method for correcting an error of the position data caused by the position data, so that the reference coordinates of the position data are relatively rotated by the inclination angle in a direction opposite to the inclination. The error is corrected by performing a rotational movement conversion on the reference coordinates and correcting it. According to the configuration employing such a data correction method, the measurement error due to the inclination of the predetermined portion is corrected irrespective of the predetermined portion (that is, the installation position of the distance measuring unit), and the accuracy of the distance measuring device for a motorcycle is corrected. Improvement can be realized.

[Brief description of the drawings]

FIG. 1 is a diagram illustrating the configuration and operation of a system including a motorcycle ranging device.

FIG. 2 is a diagram illustrating the operation of the system.

FIG. 3 is a flowchart showing the operation of the system.

FIG. 4 is a diagram for explaining a problem of the distance measuring device for a motorcycle.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Rear wheel side (non-steering wheel side) 2 Front wheel side (steering wheel side) 11 Distance measuring part 12 Control part (steering angle correction means) 13 Steering angle detection part (steering angle detection means) 15 Judgment part (tilt correction means) 14 Vehicle inclination detection unit (inclination detection means)

──────────────────────────────────────────────────の Continued on the front page (51) Int.Cl. ⁷ Identification symbol FI Theme coat ゛ (Reference) G01S 17/93 G08G 1/16 C G08G 1/16 G01S 17/88 A F term (Reference) 2F112 AD10 BA06 CA05 DA15 DA25 FA03 FA50 5H180 AA05 CC03 CC12 CC14 LL01 LL04 LL07 LL09 5J070 AC01 AC02 AC11 AE01 AF03 AK22 BF12 5J084 AA02 AA04 AA05 AA10 AB01 AC02 BA03 BA11 BB11 BB26 CA31 EA04 EA29

Claims (4)

[Claims] 1. A distance measuring unit installed on a steering wheel side of a two-wheeled vehicle to scan and irradiate a wave to a detection area in front of the two-wheeled vehicle and receive a reflected wave of the wave, and based on the reflected wave, In a motorcycle ranging device that generates at least position data of an object in a detection area, a steering angle detection unit that detects a steering angle and a steering direction of the motorcycle, and a steering direction opposite to the steering direction detected by the steering angle detection unit. Two-wheeled vehicle provided with steering angle correction means for rotating and converting the position data to correct the position data so that the reference coordinates of the position data are relatively rotated in the direction by the detected steering angle. Distance measuring device. 2. An inclination detecting means for detecting an inclination angle and an inclination direction of the motorcycle from a direction perpendicular to a road surface, and a direction opposite to the inclination direction detected by the inclination detection means by an amount corresponding to the detected inclination angle. 2. The two-wheeled vehicle distance measuring device according to claim 1, further comprising an inclination correcting means for rotationally transforming and correcting the position data so that the reference coordinates of the position data are relatively rotated. 3. A two-wheeled vehicle ranging device that scans and irradiates a wave to a detection area in front of a motorcycle and generates at least position data of an object in the detection area based on a reflected wave of the wave. Inclination detection means for detecting the inclination angle and the inclination direction of the motorcycle from a direction perpendicular to the road surface; and a reference for the position data by the detected inclination angle in a direction opposite to the inclination direction detected by the inclination detection means. A distance measuring device for a two-wheeled vehicle, comprising: inclination correcting means for rotating and converting the position data to correct the coordinates so that the coordinates are relatively rotated. 4. A distance measuring unit which is installed at a predetermined portion of the motorcycle and scans and irradiates a wave to a detection area in front of the motorcycle and receives a reflected wave of the wave, and performs the detection based on the reflected wave. In a motorcycle ranging device that generates at least position data of an object in an area, a data correction method for correcting an error in the position data due to an inclination of the predetermined portion with respect to a traveling direction of the motorcycle or a direction perpendicular to a road surface. And correcting the error by rotating and converting the position data so that the reference coordinates of the position data are relatively rotated by the tilt angle in a direction opposite to the tilt. A data correction method for a distance measuring device for a motorcycle, comprising: