JP2007255976A - Ranging method, range finder, parking support device, and ranging system - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a ranging method, a range finder, a ranging system, and a parking support system dispensing with image processing or the like, capable of determining a clearance between an obstacle and a vehicle with a simple constitution. <P>SOLUTION: In this ranging method, a progressive wave D by an ultrasonic wave is transmitted from a transmission means 3 toward a measuring object, and a reflected wave R reflected by the measuring object is received by a receiving means 4, and a separation distance between the center line of the transmission means 3 and the measuring object is measured. In the method, the reflected wave is received by the receiving means 4, and an object distance from the transmission means 3 to the measuring object is determined, and then a frequency of the progressive wave D is changed, and the separation distance is determined based on the highest frequency in the reflected wave R reflected by the measuring object and on the object distance. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a distance measuring method, a distance measuring device, a distance measuring system, and a parking assistance device.

  2. Description of the Related Art Conventionally, a vehicular travel guide device that measures a gap between a vehicle and an obstacle and informs the driver of the gap is known (see Patent Document 1).

Such a vehicle travel guidance device images an obstacle with a stereo camera, performs image processing on the captured obstacle image to obtain a gap between the obstacle and the vehicle, and displays the gap on a display to display a driver. To inform.
JP 2004-168304 A

  Such a vehicular travel guidance device measures an obstacle image captured by a stereo camera and measures the three-dimensional position of the obstacle, so that the image processing is complicated and expensive. There was a problem of becoming.

  An object of the present invention is to perform distance measurement that does not require image processing or the like, and can determine the clearance distance or height between an obstacle (measurement object) and a vehicle or the width of a recess on a road surface with a simple configuration. A method, a distance measuring device, a distance measuring system, and a parking assistance device are provided.

According to the first aspect of the present invention, the traveling wave is transmitted from the transmitting means, the reflected wave reflected by the measurement object is received by the receiving means, and the gap distance between the center line of the transmitting means and the measurement object is determined. A distance measuring method for measuring,
Receiving the reflected wave by the wave receiving means, obtaining the target distance from the sending means to the measurement object,
Thereafter, the frequency of the traveling wave is changed, and the gap distance is obtained based on the highest frequency among the reflected waves reflected by the measurement target and the target distance.

The invention of claim 12 is a distance measuring method in which a traveling wave is transmitted from a transmitting means toward a concave portion of a road surface, and a reflected wave from the concave portion is received by a receiving means, thereby measuring the width of the concave portion. And
A reflected wave that is reflected at the upper end of the outer wall portion of the recess located outside the sending means by changing the amplitude and frequency of a traveling wave having a divergence angle in the vertical direction sent from the sending means; Receiving the reflected wave reflected by the upper end of the inner wall portion of the concave portion located inside the sending means by the receiving means;
The highest frequency among the reflected waves reflected at the upper end of the outer wall portion, the highest frequency among the reflected waves reflected at the upper end of the inner wall portion, the distance between the sending means and the upper end of the outer wall portion, and the sending The width of the concave portion is obtained based on the means and the distance to the upper end of the inner wall portion.

The invention of claim 14 is provided with a sending means for sending a traveling wave and a receiving means for receiving a reflected wave reflected by the measuring object, and the height of the measuring object based on the received wave of the receiving means. A distance measuring device for
Control means for sending the traveling wave having a divergence angle in the vertical direction from the sending means and changing the frequency of the traveling wave;
A target distance calculating means for obtaining a target distance from a change in amplitude of a reflected wave received by the wave receiving means to the measurement target;
A height calculating means for calculating the height of the measurement object,
The control means changes the frequency of the traveling wave,
The height calculation means obtains the height of the measurement object from the highest frequency among the reflected waves reflected by the upper edge of the measurement object received by the wave reception means and the object distance. And

  According to the present invention, it is not necessary to perform image processing or the like, and the clearance distance to the measurement object, the height of the measurement object, or the width of the recess of the road surface can be obtained with a simple configuration.

  DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Embodiments that are embodiments of a distance measuring device, a distance measuring system, and a parking assistance device that implement a distance measuring method according to the present invention will be described below with reference to the drawings.

[First embodiment]
FIG. 1 is a block diagram showing the configuration of the distance measuring device 1. The distance measuring device 1 includes an oscillating unit 2 that outputs a high-frequency signal, and a sending unit 3 that transmits a traveling wave by an ultrasonic wave toward the measurement target M (see FIG. 2) by the high-frequency signal output from the oscillating unit 2. A receiving means 4 such as a piezo element that receives (receives) a reflected wave reflected by the measurement object, and a target distance from the sending means 3 to the measurement object when the receiving means 4 receives the reflected wave. When the distance detection means 5 for obtaining the target distance is obtained, the control means 6 for increasing the frequency of the traveling wave when the distance detection means 5 obtains the target distance, and when the reflected wave reflected by the measurement object is not received, Maximum frequency detection means 7 for detecting the highest frequency capable of receiving the reflected wave, and angle calculation means (azimuth angle calculation means) for calculating the spread angle of the traveling wave from the highest frequency detected by the highest frequency detection means 7 8 From the spread angle calculated by the angle calculation means 8 and the target distance, the distance between the center line S of the transmission means 3 (see FIG. 2: the center line S is also the center line of the traveling wave D) and the measurement object M. A gap distance detecting means (gap distance calculating means) 9 for obtaining the gap distance L and a display means 10 for displaying the gap distance L obtained by the gap distance calculating means 9 are provided.

  The oscillating means 2 has a high frequency signal generating means (not shown) for outputting a high frequency signal and a frequency changing means (not shown) for changing the frequency of the high frequency signal.

  As shown in FIG. 2, the sending means 3 is provided on the right side of the front portion of the vehicle (moving body) 11, and the wave receiving means 4 is provided next to the sending means 3.

  As shown in FIG. 3, the delivery means 3 is obtained by laminating a thin film heat generating portion 3C on a substrate 3A made of a single crystal through a thermal insulating layer 3B made of porous silicon (Japanese Patent Laid-Open No. 2004-180262). See the official gazette). Then, by appropriately controlling energization between both ends of the heat generating portion 3C, the air in contact with the heat generating portion 3C expands and contracts, and a traveling wave by ultrasonic waves is sent out.

  The directivity of the sending means 3 is determined by the size of the heat generating portion 3C and the frequency of the traveling wave. For example, when the size of the heat generating portion 3C is 20 mm in length and width and the frequency is 160 KHz (ultrasonic), it is about 10 degrees (reference) Literature: Watanabe et al., Research on directivity of thermally induced nanosilicon ultrasonic source, pp461-464, Proceeding in of 11th symposium of Microjoining and Assembly in Electronics (Mate2005), Feb.2005).

Further, the relationship between the frequency of the traveling wave D transmitted by the transmitting means 3 and the directivity is expressed by the following equation (1) (see the above-mentioned reference).

  Here, D (θd) is the relative intensity at the angle θd (1 when θ = 90 degrees (front)). f is the frequency, a is 1/2 times one side of the heat generating part (ultrasonic wave generating part), and c is the speed of sound.

  The distance detection unit 5 calculates the distance from the transmission unit 3 to the measurement target M from the time from when the traveling wave is output from the transmission unit 3 to when the reception unit 4 receives the reflected wave.

  The control means 6 outputs the transmission control signal G and controls the output timing of the high-frequency signal output from the oscillating means 2 or controls the change of the frequency of the high-frequency signal.

The distance detection means 5, the control means 6, the maximum frequency detection means 7, the angle calculation means 8, and the gap distance calculation means 9 are configured by storage means such as a CPU, ROM, and RAM, an input / output I / F, and the like. .
[Operation]
Next, the operation of the distance measuring apparatus 1 configured as described above will be described based on the flowchart shown in FIG. 4 and the time chart shown in FIG.

  When the transmission control signal G0 is output from the control means 6 in step 1 (time t1 in FIG. 5), a high-frequency signal having a frequency fs is output from the oscillation means 2 for a predetermined time (step 2). From the means 3, an ultrasonic traveling wave D0 having a frequency fs is transmitted.

  Since the frequency fs is low, the directivity of the traveling wave D0 is weak and the spread angle of the traveling wave D0 is large as shown in FIG. Due to the large spread angle of the traveling wave D0, the traveling wave D0 reaches the measuring object M in front of the vehicle 11, where a reflected wave R0 is generated.

  In step 3-1, when the wave receiving means 4 receives (receives) the reflected wave R0 (time t2), a reception signal is output from the wave receiving means 4.

  On the other hand, the distance detection means 5 counts the time from the time point t1 when the transmission control signal G0 is output from the control means 6 to the time point t2 when the reception means 4 outputs the reception signal, and at this counted time. Based on this, the target distance from the sending means 3 to the measuring object M is obtained (step 4).

  In step 5, it is determined whether or not the wave receiving means 4 has output a reception signal. Here, since the wave receiving means 4 is outputting the received signal, the process proceeds to Step 6.

  Whether the wave receiving means 4 outputs a reception signal is determined by the control means 6 when the distance detection means 5 obtains the target distance, but the control means 6 inputs the reception signal of the wave receiving means 4. You may make it judge by.

  In step 6, when the distance detection means 5 calculates | requires object distance, the control means 6 memorize | stores the frequency f0 of the reflected wave R0 which the receiving means 4 received in the memory which is not shown in figure. In step 7, it is determined whether or not the frequency of the traveling wave + the step frequency (Δf) is greater than the final frequency fa. Here, the frequency of the traveling wave is fs. For example, by setting in advance so that fs + Δf <fs + 3Δf <fa, step 7 is determined to be no and the process returns to step 1.

  In step 1, a transmission control signal G1 is output from the control means 6 (time t3 in FIG. 5), and a high-frequency signal having a frequency fs + Δf is output from the oscillation means 2 for a predetermined time (step 2). From the means 3, an ultrasonic traveling wave D1 having a frequency fs + Δf is transmitted.

  The traveling wave D1 reaches the measuring object M as shown in FIG. 2, and a reflected wave R1 is generated. Similarly to the above, when the wave receiving means 4 receives the reflected wave R1 at the time t4 shown in FIG. 5, a reception signal is output from the wave receiving means 4, and the processing operations of the above steps 4 to 5 are performed. In step 6, the previously stored fs is updated to fs + Δf, and the process proceeds to step 7.

  In step 7, it is determined whether or not fs + 2Δf> final frequency (fa). Here, it is determined no based on the above-described relationship, and the process returns to step 1.

  In step 1, a transmission control signal G2 is output from the control means 6 (time t5 in FIG. 5), a high-frequency signal having a frequency fs + 2Δf is output from the oscillating means 2 for a predetermined time (step 2), and is transmitted in step 3. From the means 3, an ultrasonic traveling wave D2 having a frequency fs + 2Δf is transmitted.

  The traveling wave D2 reaches the measurement object M as shown in FIG. 2, and a reflected wave R2 is generated. Therefore, when the receiving means 4 receives the reflected wave R2 at time t6 shown in FIG. The reception signal is output from the wave means 4 and the processing operations of Step 4 to Step 5 are performed. In Step 6, the frequency stored in the memory is updated to fs + 2Δf, and the process proceeds to Step 7.

  In step 7, it is determined whether or not fs + 3Δf> final frequency (fa). Here, it is determined no based on the above-described relationship, and the process returns to step 1.

  In step 1, a transmission control signal G3 is output from the control means 6 (time t7 in FIG. 5), and a high-frequency signal having a frequency fs + 3Δf is output for a predetermined time from the oscillation means 2 (step 2). Transmits an ultrasonic traveling wave D3 having a frequency fs + 3Δf.

  Since the traveling wave D3 does not reach the measurement object M with sufficient intensity as shown in FIG. 2, the reflected wave R3 cannot be received by the wave receiving means 4.

  When the reflected wave R3 is not received even after a lapse of T1 from the time point t7, the control means 6 determines NO in step 5 and proceeds to step 9. Each T1 shown in FIG. 5 is a time for determining whether or not the receiving means 4 receives the reflected wave R from the time when the traveling wave D is sent from the sending means 3.

  In step 9, the highest frequency of the traveling wave D is detected, that is, the frequency stored in the memory is read out. In this case, fs + 2Δf, which is the frequency of traveling wave D2, is the highest frequency.

  In step 10, the azimuth angle with respect to the measuring object M that is an obstacle, that is, the radiation angle 2θ of the frequency fs + 2Δf is obtained from the frequency fs + 2Δf of the traveling wave D2.

  In step 11, the distance L between the measuring object M and the vehicle 11 from the half of the radiation angle 2θ and the target distance obtained in step 4, that is, the center line S of the sending means 3 (see FIG. 2). ) And the measuring object M is obtained, the obtained gap distance L is displayed on the display means 10, and the process is terminated.

  If YES in step 7, that is, if the reflected wave R is received even when the frequency of the traveling wave D is higher than the final frequency fa, it is assumed that the gap distance L is very small, and in step 8 the gap distance is very small. Display on means 10 and finish.

By the way, as the frequency of ultrasonic waves increases, the atmospheric attenuation increases. In general, the attenuation β is obtained by the following equation (2).

  Where η is the atmospheric viscosity coefficient and ρ is the atmospheric density.

  As described above, the atmospheric attenuation increases as the frequency increases. Therefore, if the intensity (amplitude) of the traveling wave D is changed, that is, increased as the frequency is increased, the measurement target M is increased even if the frequency of the traveling wave D is increased. If there is, the wave receiving means 4 will surely receive the reflected wave. That is, regardless of the frequency of the traveling wave D, the distance to the measurement object M can be obtained reliably.

  According to this embodiment, if the frequency of the traveling wave D is changed, the gap between the vehicle and the measuring object M can be obtained, so that it is not necessary to perform image processing or the like, and with a simple configuration. An inexpensive distance measuring device 1 can be provided.

  Further, when the vehicle is advanced, the gap between the vehicle 11 and the measurement object M can be predicted, so that the steering angle can be supported on a narrow road and the convenience such as obstacle avoidance and parking assistance can be provided. improves.

Further, since the gap distance is displayed on the display means 10 in step 8, it is immediately determined that the vehicle 11 cannot enter, and therefore it is possible to prevent the vehicle from inadvertently entering a narrow road.
[Second Embodiment]
FIG. 6 shows the configuration of the distance measuring apparatus 100 of the second embodiment. This distance measuring apparatus 100 is provided with a narrow angle object detection area setting means 50 in the distance measuring apparatus 1.

As shown in FIG. 7, when the measuring object M is detected at the position of the gap distance d1 by the traveling wave D having the intensity W1, the distance measuring device 100 has another distance farther than the measuring object M in the gap distance d1. When there is a measurement object M1, there is a possibility that it cannot be detected with the traveling wave D of intensity W1, and in this case, the intensity (amplitude) of the traveling wave D is increased and the distance in the region d1 is measured again. is there.
[Operation]
Next, the operation of the distance measuring apparatus 100 will be described based on the flowchart shown in FIG.

  The flowchart shown in FIG. 8 is obtained by inserting the processing operations of Step A12 to Step A16 between Step 9 and Step 10 of the flowchart shown in FIG. 4, and will be described based on Step A12 to Step A16. To do.

  When the traveling wave D3 is transmitted from the transmitting means 3, the reflected wave R3 does not occur because it does not hit the measuring object M as shown in FIG. In this case, the process proceeds from step 5 to step 9 shown in FIG. 4 and the processing operation of step 9 is performed.

  In step A12 shown in FIG. 8, a search distance measurement area is set. That is, the search area shown in FIG. 7 is set by the narrow-angle target detection area setting means 50.

  This search area is set by setting, for example, a frequency 5 kHz higher than the highest frequency fs + 2Δf detected in step 9 as an initial frequency, and setting the intensity W3 to be greater than the intensity (amplitude) of the traveling wave D3. Then, the narrow-angle target detection region setting unit 50 sends an information instruction signal indicating a new initial frequency and intensity to the control unit 6.

  In step A13, the control means 6 sends out a transmission control signal, whereby an ultrasonic traveling wave D (first traveling wave) of intensity W3 is sent out from the sending means 3. The frequency of the traveling wave D is the initial frequency set as described above.

  In step A14, it is determined whether or not a received wave is detected, that is, whether or not the wave receiving means 4 receives the reflected wave R and outputs a received signal.

  If no, it is determined that there is no other detection unit, that is, the measurement object M1 during the gap distance d1.

  If the wave receiving means 4 receives the reflected wave R from the measurement object M1, it is determined as YES in step A14, and the process proceeds to step A15. In step A15, the frequency of the traveling wave D is updated, and the process proceeds to step A16.

  Then, while the wave receiving means 4 receives the reflected wave R, the processing operation of step A16 to step A12 is repeated, and the frequency of the traveling wave D is increased in the same manner as in the first embodiment, and the search is performed. The area will be narrowed.

  When the receiving means 4 no longer receives the reflected wave R from the measurement object M1, the process proceeds to steps 10 to 11 when it is determined NO in step A14, and the progress immediately before the receiving means 4 stops receiving the wave. Based on the frequency (second frequency) of the wave D, a gap distance d2 between the center line S of the sending means 3 and the measuring object M1 is obtained, and this gap distance d2 is displayed on the display means 10 and the process is terminated.

  When it is determined as YES in step A16, that is, when the frequency of the traveling wave D becomes higher than the final frequency (preset frequency), it is determined that the gap distance d2 is very small. It will be displayed and finished.

  According to the second embodiment, the frequency and intensity (amplitude) of the traveling wave D are increased in order to exclude the known measuring object M and detect a new measuring object M1 that becomes an obstacle in traveling the vehicle. Therefore, even a distant obstacle (measurement target M1) in which the amplitude of the reflected wave is small can be reliably detected. In addition, when the frequency of the traveling wave D is increased by the processing operation from step A16 to step A12, if the intensity (amplitude) of the traveling wave D is increased in accordance with the height of this frequency, the measurement can be performed more reliably. The target M can be detected.

Further, since the search area is narrowed to increase the intensity (amplitude) of the traveling wave D and limit the search area in the vehicle traveling direction, information necessary for traveling the vehicle 11 can be quickly detected. For this reason, the allowance time until collision avoidance can be increased.
[Third embodiment]
FIG. 9 shows the configuration of a vehicle ranging system 200 provided with a pair of ranging devices 1 of the first embodiment.

  The distance measuring system 200 includes a left distance measuring device unit 1L that measures a distance on the left side of the vehicle, a right distance measuring device unit 1R that measures a distance on the right side of the vehicle, a road width calculating unit 210 that calculates a road width, and the like. And an operation timing instruction means 212 for instructing the operation timing to the control means 206L and 206R.

  The sending means 3L and the receiving means 4L of the left ranging device unit 1L are provided on the left side of the front part of the vehicle, and the sending means 3R and the receiving means 4R of the right ranging device unit 1R are on the right side of the front part of the vehicle. Is provided. The sending means 3L and the sending means 3R are arranged, for example, about 1.8 m apart on the left and right in the vehicle width direction. Similarly, the wave receiving means 4L and 4R are arranged, for example, about 1.8 m apart on the left and right.

In FIG. 9, 206L and 206R are control means similar to those in the first embodiment, and 209L and 209R are gap distance detection means similar to those in the first embodiment.
[Operation]
Next, the operation of the distance measuring system 200 will be described based on the flowchart shown in FIG.

  In step 601, the operation timing instruction unit 212 transmits an operation timing signal to the control units 206L and 206R so that the traveling waves of the same frequency are not simultaneously transmitted from the transmission units 3L and 3R of the left and right distance measuring device units 1L and 1R. For example, an operation timing signal is transmitted to the control unit 206L, and the traveling wave D is transmitted from the transmission unit 3L of the left distance measuring device unit 1L.

  Then, the control means 206L increases the frequency of the traveling wave DL transmitted from the transmission means 3L in the same manner as in the first embodiment, and when this frequency becomes 20 KHz higher than the initial frequency, the operation timing instruction means 212. Transmits an operation timing signal to the control means 206R, and causes the traveling wave DR to be transmitted from the transmission means 3R of the right distance measuring device unit 1R.

  The control means 206R increases the frequency of the traveling wave DR transmitted from the transmission means 3R in the same manner as in the first embodiment. At this time, the control means 206L also increases the frequency of the traveling wave DL.

  The traveling waves DL and DR may be alternately sent from the sending means 3L and 3R of the left and right distance measuring device units 1L and 1R.

  In the same manner as in the first embodiment, the gap distances dintL and dintR between the vehicle 11 and the side walls KL and KR shown in FIG. 11 are obtained by the gap distance detection means 209L and 209R of the left and right distance measuring device units 1L and 1R. .

  In step 602, the road width calculation means 210 receives the gap distances dintL and dintR obtained by the gap distance detection means 209L and 209R.

  In step 603, it is determined whether or not the gap distances dintL and dintR are greater than a preset threshold value. If no, the process proceeds to step 605. That is, when either of the gap distances dintL and dintR is equal to or smaller than the threshold value, the road width calculation unit 210 outputs a straight travel impossible signal and the process ends. This inability to go straight is displayed on the display means 10.

  If it is determined as YES in step 603, the process proceeds to step 604. In step 604, the road width calculation means 210 obtains the road width dw from the gap distances dintL and dintR and the vehicle width (1.8 m) and displays it on the display means 10, and the process is terminated.

  According to the third embodiment, since it is possible to determine whether or not a vehicle can pass on a narrow road, it is possible to reduce the driver's driving load on the narrow road.

In addition, according to the third embodiment, in the case of passing between vehicles, for example, information on whether or not the vehicle can be entered can be presented to the driver in advance, so that the driver's anxiety while the vehicle is traveling can be eased.
[Fourth embodiment]
FIG. 12 shows the configuration of a distance measuring device 300 for obtaining the height of the curb (measuring object).

  In FIG. 12, reference numeral 2003 denotes a sending means provided with a horn (not shown) so that the directivity becomes a narrow angle. In this embodiment, the horizontal detection range (directivity) is narrowed so as not to detect unnecessary ones. The traveling wave is transmitted so that the spread angle is in a direction perpendicular to the road surface. This sending means 2003 is provided in the lower part of the front part or the rear part of the vehicle.

  In FIG. 12, 2005 is a distance detecting means for obtaining a distance L5 from the sending means 2003 to the curb 301 shown in FIG. 13, and 2006 is a distance measuring area detecting means (ranging area setting means for setting a vertical distance measuring area. ), 8 is an elevation angle calculation means that is θA shown in FIG. 13, 2007 is a control means (target distance calculation means) that controls the oscillation means 2 based on the distance measurement area information, and 2009 is an angle of the curb 301 from the elevation angle θA and the like. Curb height calculating means (height calculating means) for calculating the height AH and judging whether the vehicle 11 can get over the curb 301, 2010 is the wave receiving means 4 receiving the reflected wave within the maximum standby time Ranging area evaluation means 2011 for evaluating whether or not, road surface correction means.

The distance detection means 2005, the control means 2007, the distance measurement area detection means 2006, the distance measurement area evaluation means 2010, the curb height calculation means 2009, the elevation angle calculation means 8, and the like are storage means such as a CPU, ROM, and RAM, and input / output. It is comprised by I / F etc.
[Operation]
Next, the operation of the distance measuring apparatus 300 will be described based on the flowchart shown in FIG.

  In step 2120, the control means 2007 outputs an initial transmission control signal, and a high frequency signal having an initial frequency (for example, 30 KHz) is outputted from the oscillation means 2 (step 2121).

  In step 2122, an ultrasonic traveling wave D having a large intensity (amplitude) is sent from the sending means 2003 toward the curb 301 shown in FIG. 13, and a reflected wave reflected by the curb 301 is received by the wave receiving means 4. (Received).

  In step 2123, the distance detection means 2005 determines the distance L5 from the sending means 2003 to the curbstone 301.

  In step 2124, it is determined whether the curb 301 has been detected. In other words, if the distance L5 to the curb 301 is not obtained by the distance detection means 2005, it is considered that there is no curb 301 or an obstacle, and it is determined as no and the process ends.

  Here, since the distance L5 to the curb 301 is obtained, it is determined as YES in step 2124, and the process proceeds to step 2125.

  In step 2125, the distance measurement area setting unit 2006 sets the distance measurement area A1 shown in FIG. 13 based on the distance L5. When a plurality of obstacles (curbstones) are detected, a distance measurement area is set based on the obstacle at the closest distance. Here, description will be made assuming that the curb 301 is at the closest distance.

  In step 2126, the intensity W1 and the frequency of the traveling wave D are determined according to the distance measurement area A1. That is, the intensity W1 at which the traveling wave D reaches the curb 301 is determined, and the frequency is determined, for example, 150 KHz. And the control means 2007 outputs the transmission control signal which has the information of intensity | strength W1 and frequency 150KHz.

  In step 2127, a traveling wave D having a strength W1 of 150 KHz is sent from the sending means 2003 toward the curb 301 shown in FIG.

  In step 2128, it is determined whether or not the wave receiving means 4 has received the reflected wave R from the curb 301, that is, whether or not the wave receiving means 4 has output a reception signal. .

  In step 2134, the frequency is updated from 150 KHz to 150 KHz−Δf (for example, 5 KHz), and the process returns to step 2126.

  Then, until the wave receiving means 4 receives the reflected wave R from the curb 301, the processing operations of Step 2126 to Step 2128 are repeated. By this repeated processing operation, the frequency of the traveling wave D transmitted from the transmitting unit 2003 is gradually shifted from 150 KHz to a lower frequency by Δf until the receiving unit 4 receives the reflected wave R from the curb 301. To go.

  As the frequency of the traveling wave D becomes lower, the directivity of the traveling wave D becomes weaker and the spread angle θ1 of the traveling wave D becomes larger. As the spread angle θ1 increases, the traveling wave D reaches the upper end TA of the curb 301 and the reflected wave R is generated.

  When the reflected wave R is received by the wave receiving means 4, it is judged as YES in Step 2128 and the process proceeds to Step 2129.

  In step 2129, the frequency updated in step 2134 is detected, and in step 2130, the spread angle θ1 that is the elevation angle of the curb 301 is calculated from the frequency of the traveling wave D in which the reflected wave R is generated.

  In step 2131, a distance (target distance) L is obtained from the distance L5 and the installation height H (the installation height at which the delivery means 2003 is provided is known), and further, the gap distance DA from the angle θ1 and the distance L. And the height AH of the curb 301 is obtained from the gap distance DA and the installation height H. Then, it is determined whether or not the vehicle 11 gets over based on the height AH, and the result and the installation height AH are displayed on the display means 10.

  In step 2132, it is determined whether the height has been obtained for all obstacles. If no, go to Step 2133.

  In step 2133, the distance of the next closest obstacle is read, and the height of the obstacle is obtained in the same manner as described above.

  If the heights of all the obstacles are obtained, it is determined as YES in step 2132 and the process ends.

  By the way, the frequency of the traveling wave D is lowered in step 2134. If the reflected wave R is not obtained even when the traveling wave D becomes the lowest frequency, the curb 301 cannot be detected. End as

  In addition, when the traveling wave D having a frequency of 150 KHz is transmitted from the transmitting unit 2003 in step 2127, when the reflected wave R is received by the receiving unit 4, the height of the transmitting unit 2003 is not less than the installation height H. Since there is an obstacle to be held, a message “impossible to get over the obstacle” is displayed on the display means 10 and the process is terminated.

  In the above embodiment, when the frequency of the traveling wave D is lowered, the spread angle θ1 is calculated from the frequency of the traveling wave D in which the reflected wave R is generated, and the height of the obstacle is obtained. The frequency of the wave D is changed from a low frequency to a high frequency, and the spread angle θ1 is calculated from the highest frequency of the traveling wave D generated by the reflected wave R at this time, and the height of the obstacle is determined. You may ask for it.

  Moreover, in the said Example, although the road surface was horizontal, the height AH of the curb 301 was calculated | required, but when the road surface is inclined, the height AH of the curb 301 is calculated | required as follows.

  If the gap distance DR with respect to the road surface in front of the curb 301 is measured, the estimated value of the road surface inclination can be geometrically calculated from the gap distance DR and the installation height H of the sending means 2003. Here, the clearance distance DR is measured as follows.

  Assuming that the road surface is horizontal, the angle θA shown in FIG. 13 can be geometrically calculated based on the distance L5 and the installation height H. The frequency corresponding to the angle N times (for example, 1.5 times) of the angle θA and the intensity of the traveling wave that does not reach the distance L5, that is, the intensity equal to or lower than a predetermined threshold that does not receive the reflected wave from the curb 301 are initially set. As a value, a traveling wave is transmitted from the transmission means 2003. The reason why the angle θA is increased N times is to ensure that the road surface enters the distance measurement area.

  The traveling wave frequency is gradually increased to narrow the vertical ranging area. Immediately after the start of measurement, since the road surface enters the distance measurement area, the wave receiving means 4 receives the reflected wave from the road surface. When the frequency reaches a certain frequency, the frequency measurement area receives the reflected wave. The road surface is not included, and the wave receiving means 4 does not receive the reflected wave from the road surface (this point is called a vanishing point). The separation distance corresponding to the frequency of the traveling wave at this vanishing point is DR.

  Θa can be obtained from the frequency of the traveling wave at the vanishing point, and by receiving the reflected wave R from the vanishing point, a distance L6 from the sending means 2003 to the vanishing point is obtained, and the distance L6 and the angle θa are obtained. Based on the above, the horizontal distance La from the position of the sending means 2003 to the vanishing point is obtained.

  The slope of the road surface in the direction of the center line S is obtained from the horizontal distance La, the installation height H, and the gap distance DR, and the height of the road surface on which the curb 301 is located based on the slope of the road surface, the installation height H, and the distance L. The height is obtained, and the height of the curb 301 is obtained from the height position of the road surface, the installation height H, and the gap distance DR.

  That is, the height position of the road surface on which the curb 301 is located is geometrically calculated based on the installation height H, the gap distance DR, the distance L, the gap distance DA, etc., and the road surface height position and the gap distance DA The height of the curb 301 is obtained from the installation height H.

  The slope of the road surface is obtained by the road surface correction means 2011, and the height of the curb 301 obtained in step 2131 may be corrected by obtaining the height position of the road surface on which the curb 301 is located as described above.

According to this embodiment, the height AH of the curb 301 is obtained, and whether or not the vehicle 11 can get over is displayed on the display means 10 based on the height AH. In the case of emergency avoidance, it is very convenient and can reduce the driver's load. In addition, when the user cannot get over the vehicle, the driver is warned and unnecessary driving operations are not required.
[Fifth embodiment]
FIG. 15 shows the configuration of a distance measuring device 400 that measures the width of a side groove (concave portion) or the like.

  The sending means 2003 and the wave receiving means 4 shown in FIG. 15 are provided on the side of the vehicle, and a transmission wave is sent from the sending means 2003 outward in the vehicle width direction.

In FIG. 15, reference numeral 2706 denotes an obstacle ranging area setting means for setting the ranging area in the same manner as the ranging area setting means 2006 of the fourth embodiment. Reference numeral 2707 denotes the frequency of the traveling wave sent from the sending means 2003. Control means 2709 for setting the intensity, etc., when the reflected wave is received in the distance measurement area set by the distance measurement area setting means 2006, the end of the obstacle (the end TB1 of the side groove 301) shown in FIG. An obstacle position calculating means (first horizontal distance calculating means, second horizontal distance calculating means) for obtaining the position of TB2), 2711 a side groove detecting means for detecting the side groove 301, and 2712 for a road surface for setting a distance measuring area of the road surface. It is a ranging area setting means.
[Operation]
Next, the operation of the distance measuring device 400 will be described based on the flowchart shown in FIG.

  In step 3101, the distance measurement area is set in a wide range so that the road surface distance measurement area setting means 2712 can detect the side groove 301 (the frequency of the traveling wave D is set low and the intensity is set large).

  In step 3102, the control means 2707 outputs a transmission control signal according to the setting of the road surface ranging area setting means 2712, and the progress of ultrasonic waves having low frequency and high intensity from the sending means 2003 via the oscillation means 2. A wave is sent out.

  In step 3103, it is determined whether or not the wave receiving means 4 has received the reflected wave R reflected by the side wall portion 301 </ b> A that is the outer wall portion of the side groove 301. If the reflected wave is not received, the process proceeds to step 3104, where the intensity of the traveling wave D is set to be stronger and the process returns to step 3102.

  If YES is determined in the step 3103, the process proceeds to a step 3105. In step 3105, it is determined whether or not the distance to the side wall 301 </ b> A of the side groove 301 has been obtained. If no, the process proceeds to step 3104, and if yes, the process proceeds to step 3106. Since the intensity of the reflected wave reflected by the side wall portion 301A of the side groove 301 is increased, the distance Lb1 from the sending means 2003 to the upper end TB1 of the side wall portion 301A of the side groove 301 is known. This distance (first upper end distance) Lb1 is obtained by the distance detecting means (upper end distance calculating means) 2005.

  In step 3106, the intensity Wa of the traveling wave D that can be measured to the distance Lb1 is set, and the maximum frequency of the traveling wave D is set to 150 KHz, for example. These settings are made by the obstacle ranging area setting means 2706. Then, the control means 2707 outputs a transmission control signal for setting the frequency of the traveling wave D to 150 KHz and the intensity to Wa.

  In step 3107, a traveling wave D having a frequency of intensity Wa of 150 KHz is sent from the sending means 2003 toward the side groove 301 shown in FIG.

  In step 3108, it is determined whether or not the wave receiving means 4 has received the reflected wave R reflected by the upper end TB1 of the side wall portion 301A of the side groove 301, that is, whether or not the wave receiving means 4 has output a reception signal. If no, go to step 3110.

  In step 3110, the frequency is updated from 150 KHz to 150 KHz−Δf (for example, 5 KHz), and the process returns to step 3106.

  Until the wave receiving means 4 receives the reflected wave R from the upper end TB1 of the side wall 301A of the side groove 301, the processing operations of Step 3106 to Step 3108 and Step 3110 are repeated. By this repeated processing operation, the frequency of the traveling wave D sent from the sending means 2003 is stepped from 150 KHz until the wave receiving means 4 receives the reflected wave R from the upper end TB1 of the side wall portion 301A of the side groove 301. The frequency is shifted to a lower frequency by Δf.

  As the frequency of the traveling wave D becomes lower, the directivity of the traveling wave D becomes weaker and the spread angle θb1 of the traveling wave D becomes larger. As the spread angle θb1 increases, the traveling wave D reaches the upper end TB1 of the side wall portion 301A of the side groove 301, and a reflected wave R is generated.

  When the wave receiving means 4 receives the reflected wave R, it is judged as YES in Step 3108 and the process proceeds to Step 3109.

  In step 3109, the frequency updated in step 3110 is detected. In step 3111, the elevation angle θb1 shown in FIG. 16 is calculated from the frequency of the traveling wave D in which the reflected wave R is generated. A distance DB1 (a distance between the center line of the sending unit 2003 and the upper end TB1 of the side wall portion 301A) is obtained. The elevation angle θb1 is calculated by the elevation angle calculation means 8. In other words, the angle of attack is determined from the highest frequency among the frequencies at which the reflected wave R is generated.

  In step 3112, an accurate horizontal distance (outer wall distance) L1 (Lb1 × cos (θb1)) from the sending means 2003 to the side wall 301A of the side groove 301 is calculated from the angle of attack θb1 and the distance Lb1. This horizontal distance L1 is calculated by the obstacle position calculation means 2709.

  In step 3113, the horizontal distance L2 from the sending means 2003 to the side wall 301B which is the inner side wall portion of the side groove 301 is calculated in the same manner as described above.

  Here, the intensity of the traveling wave D is set to Wb smaller than Wa so that the reflected wave from the side wall portion 301A of the side groove 301 is not generated. In addition, the distance measurement area is gradually expanded by changing the frequency of the traveling wave D from the higher side to the lower side. The intensity and frequency of the traveling wave D are set by the road surface ranging area setting means 2712.

  A reflected wave is generated at the upper end TB <b> 2 of the side wall 301 </ b> B of the side groove 301 by lowering the frequency and gradually widening the distance measurement area. Then, based on the frequency at which the reflected wave is first obtained, the angle of attack θb2 shown in FIG. 16, the distance from the sending means 2003 to the upper end TB2 of the side wall 301B of the side groove 301 (second upper end distance) Lb2, and the gap A distance DB2 (a distance between the center line S of the sending means 2003 and the upper end TB2 of the side wall portion 301B) is obtained.

  Here, the elevation angle θb2 is obtained based on the highest frequency among the frequencies at which the reflected wave is generated near the upper end TB2.

  Further, the distance detection unit 2005 obtains the distance Lb2. Then, an accurate horizontal distance L2 (Lb2 × cos (θb2)) from the sending means 2003 to the side wall 301B of the side groove 301 is calculated from the elevation angle θb2 and the distance Lb2. This horizontal distance (inner wall distance) L2 is calculated by the obstacle position calculating means 2709.

  If the intensity Wb of the traveling wave D is slightly smaller than Wa, the distance is measured at the upper end TB1 of the side groove 301. In this case, the calculated distance is Lb1, and in this case, further The intensity Wb of the traveling wave D is weakened.

  On the contrary, if the strength Wb is too weak, the distance to the road surface before the upper end TB2 is measured without measuring the distance to the upper end TB2 of the side groove 301. We gradually weaken it so that it does not become L1.

  In step 3114, the width WB (L1-L2) of the side groove 301 is calculated from the distance L1 and the distance L2. This calculation is performed by the side groove detecting means 2711.

  In step 3115, it is determined whether or not the vehicle 11 can pass over the side groove 301 based on the width WB of the side groove 301, that is, whether or not the vehicle 11 gets over the side groove 301. For example, when the width WB is 20 cm or more, it cannot be overridden, and when the width WB is smaller than 20 cm, it can be overridden. .

According to this embodiment, when there is a groove such as a side groove around the vehicle 11, the width of the groove is measured, and it is determined whether or not the vehicle 11 can travel and displayed on the display means 10. The driving load of the driver can be reduced.
[Sixth embodiment]
FIG. 18 is a block diagram showing the configuration of the parking assistance device 500.

  The parking assistance device 500 includes a parking space detection means 720, an obstacle relative position acquisition means 721, a distance measurement area setting means 724, a parking assistance information calculation means (steering angle calculation means) 722, and a parking assistance information display means 723. Distance measuring means (first and second distance measuring means) 725L, 725R, parking end instruction means 726, and the like.

  As shown in FIG. 19, the parking space detecting means 720 includes a transmitting means 702 that outputs a high-frequency signal, a sending means 703 that sends a traveling wave D, a receiving means 704 that receives a reflected wave R, and an obstacle. Distance detecting means 705 for detecting the distance up to, a transmission control means 706, and the like. These means 702 to 706 are substantially the same as those shown in FIG. The sending means 703 and the wave receiving means 704 are provided on the left side of the vehicle 11 shown in FIG. The obstacle relative position acquisition unit 721, the distance measurement area setting unit 724, the parking support information calculation unit 722, and the like are configured by an ECU.

  The distance measuring means 725L and 725R have the same configuration as the left distance measuring device unit 1L and the right distance measuring device unit 1R shown in FIG.

  As shown in FIG. 20, the sending means 3L (see FIG. 9) and the wave receiving means 4L are provided on the left side of the rear part of the vehicle 11, and the sending means 3R and the wave receiving means 4R are on the right side of the rear part of the vehicle 11. Is provided.

The parking end instruction means 726 detects the gear state of the transmission, and outputs an end signal when the shift lever is moved to the parking or neutral position or when an end signal is sent from the driver via the input I / F. It is sent to the obstacle relative position acquisition means 721.
[Operation]
Next, the operation of the parking assistance apparatus 500 will be described based on the flowcharts shown in FIGS.

  In step 801, a parking space is detected. This detection is performed by the parking space detection means 720. The parking space detection means 720 detects the parking space according to the process shown in the flowchart of FIG. Hereinafter, description will be made based on the flowchart shown in FIG.

  In step 901, the vehicle 11 is advanced as shown in FIG. 20A, the traveling wave D is transmitted from the transmitting means 703 of the parking space detecting means 720, and the reflected wave R is received by the receiving means 704. To measure the distance to the obstacle.

  In step 902, when the vehicle 11 is moved by a predetermined distance (for example, 3 m), the distance measurement is terminated.

  Here, for example, as shown in FIG. 20A, it is assumed that the vehicles 11U and 11V are parked and there is a space between the vehicles 11U and 11V.

  As the vehicle 11 travels, distance measurement is performed by the parking space detecting means 720 as the vehicle 11 travels, for example, each position P1,. In FIG. 20 (B), time points Ta ... indicate the time points at which the respective positions P1 ... are measured, positions P1-P4, P9-P12 indicate the front positions of the vehicles 11U, 11V, and positions P5-P8 are spaces. Depth position is shown.

  In step 903, it is determined whether or not there is a space of a vehicle length (for example, 4.5 m) or more and a vehicle width (for example, 2 m) from the distance measurement distance distribution (ranging distance to each position P1...). Here, it is determined from the distance from the positions P5 to P8 and the distance between the positions P4 and P9. If no, the process proceeds to step 906, and “no parking space” is displayed on the parking assistance information display means 723. To finish.

  If it is determined as YES in step 903, the process proceeds to step 904, “parking space present” is displayed on the parking support information display unit 723, and the process proceeds to step 905.

  In step 905, based on the distance distribution, the end points of the obstacle, for example, the positions of A and B (first and second obstacles) in FIG. 20B, that is, position P4 in FIG. 20A. P9 is obtained, sent to the obstacle relative position acquisition means 721, and the process ends.

  The obstacle relative position acquisition unit 721 acquires the end points (positions P4 and P9) of the obstacle (step 802). In step 803, the distance measurement area is set, and the position coordinates of the end points A and B of the obstacle are obtained as shown in FIG.

  The setting and position coordinates of the distance measurement area are performed based on the flowchart of FIG. 23, and will be described below based on the flowchart of FIG.

  In step 1101, a distance measurement area for measuring the relative relationship between the end point of the obstacle and the position of the host vehicle 11 is set. For example, as shown in FIG. 24A, a distance measuring area AE1 is set by the distance measuring means 725L to capture the end point A (position P9), and the distance measuring means 725L is used to capture the end point B (position P4). A distance measurement area BE1 is set. Similarly, a distance measurement area (not shown) by distance measurement means 725R is set.

  In step 1102, the positional relationship between the end points A and B of the obstacle and the sending means 3L and 3R provided on both sides of the rear portion of the vehicle 11 is grasped. This grasping is performed by sending a traveling wave from the sending means 3L, 3R based on the distance measuring area and measuring the distance to the end points A, B.

  In step 1103, it is determined whether or not the distance between the end point A and the sending means 3L is smaller than the distance between the end point A and the sending means 3R. If yes, the process proceeds to step 1104. In this embodiment, as shown in FIG. 24A, since the distance between the end point A and the sending means 3L is smaller than the distance between the end point A and the sending means 3R, the process proceeds to step 1104.

  In step 1104, a ranging instruction signal is output from the ranging area setting unit 724 to the ranging unit 725L.

  If NO is determined in step 1103, the process proceeds to step 1105, and a distance measurement instruction signal is output from the distance measurement area setting unit 724 to the distance measurement unit 725R.

  In step 1106, it is determined whether or not a distance measurement instruction signal for measuring the distance between all the end points, that is, the end points A and B, is output. If NO, the process returns to step 1102, and if YES, the process proceeds to step 1107.

  As in the first embodiment, the distance measurement instruction signal changes the frequency of the traveling wave to measure the gap distance between the vehicle 11 and the obstacle, or the separation distance that is a linear distance between the vehicle 11 and the obstacle. This is a signal for measuring the (target distance).

  In step 1107, the data (gap distance, separation distance, azimuth, etc.) measured by the distance measuring means 725L, 725R is sent to the obstacle relative position acquisition means 721 (step 804).

  In step 1108, the position coordinates and the like of the obstacle end points A and B relative to the vehicle 11 are calculated based on the received data, and the calculated relative position coordinates and the like of the obstacle end points A and B are parked support information. The data is sent to the calculation means 722 and the process ends.

  When the parking assistance information calculation means 722 receives data such as the relative position coordinates of the obstacle end points A and B (step 805), the process proceeds to step 806.

  In step 806, the parking assistance information calculation means 722 avoids the obstacle end points (measurement targets) A and B based on the position coordinates of the obstacle end points A and B, that is, based on the gap distance and the target distance. The calculated steering angle is displayed on the parking assistance information display means 723.

  As shown in FIG. 24A, when the vehicle 11 moves backward, the end point A comes closest to the vehicle 11. Here, it is evaluated whether it is possible to enter between the end points A and B without colliding with the end point A with a radius equal to or greater than the known minimum turning radius. At the same time, it is evaluated whether it is possible to enter between the end points A and B without colliding with the end B with the minimum radius.

  Further, when the vehicle has to enter at a minimum turning radius or more, since the position coordinates of the end points A and B and the position of the vehicle 11 can be measured, the parking assistance information display means 723 determines the steering angle of the vehicle by a known method. The calculated steering angle is displayed on the parking assistance information display means 723.

  In step 807, it is determined whether or not parking is completed. If no, the process returns to step 803, and if yes, the process ends. This parking determination is made by sending an end signal from the parking end instruction means 726.

  Note that only the distance from the vehicle 11 to the end points A and B and the distance between the end points A and B are simply displayed on the parking assistance information display means 723, and reference information for determining the steering angle for the driver. It may be a thing.

  By the way, when the vehicle 11 moves backward, an entry monitoring means 727 (see FIG. 18) is provided in which a distance measurement area is set so as not to capture the end points A and B of the obstacle, and the inside of the parking space is prevented from coming into contact with the adjacent vehicle. You may monitor. For example, as shown in FIGS. 24B to 24D, by providing areas AE2, BE2, BE3 for capturing the end points A, B and distance measurement areas C, D, obstacles other than the end points A, B, For example, an adjacent vehicle or an intruder can be detected.

  In this embodiment, as described above, when there is a space between the vehicles 11U and 11V and there is a space between the vehicles 11U and 11V, it is determined whether or not the space can be parked. Then, when parking is possible, a ranging area is set as shown in FIG. 24A so as to detect obstacles A and B on both sides of the entrance of the parking space. At this time, the obstacle A measures the distance by the distance measuring means 725L located near the obstacle A.

  In the same manner as in the first embodiment, the distance between the vehicle 11 and the obstacles A and B and the distance to the obstacles A and B are calculated, and the steering angle is calculated so as not to contact the obstacles A and B. The steering angle is presented to the driver. When the vehicle 11 passes the obstacles A and B, the gap distance between the adjacent vehicles 11U and 11V is measured and presented to the driver.

  According to this embodiment, an appropriate steering angle is calculated based on the positional relationship between the end points A and B and the vehicle 11, the distance between the end points A and B, and the like, and displayed on the parking assistance information display means 723. Therefore, the steering wheel operation during parking is very difficult.

  Further, since the parking space is detected by the parking space detecting means 720, the vehicle can be surely parked in the parking space. The parking space detecting means 720 is not always necessary and may be omitted.

  Although the said Example demonstrated what applied all to the vehicle 11, it is not necessarily limited to a vehicle, For example, it can apply also to a ship, a robot, etc.

  Further, the present invention is not limited to the above-described embodiments, and various design changes can be made without departing from the scope of the invention.

1 is a block diagram showing a configuration of a distance measuring apparatus according to a first embodiment of the present invention. It is explanatory drawing which showed the relationship between the frequency of a traveling wave, and a ranging range. (A) It is sectional drawing which showed the structure of sending means, (B) It is the top view which showed the structure of sending means. It is the flowchart which showed the processing operation of the distance measuring device of 1st Example. 2 is a time chart showing the operation of the distance measuring device of FIG. 1. It is the block diagram which showed the structure of the distance measuring device of 2nd Example. It is explanatory drawing which showed the ranging area for a search. It is the flowchart which showed a part of operation | movement of the ranging device of 2nd Example. It is the block diagram which showed the structure of the ranging system. It is the flowchart which showed the processing operation of the ranging system. It is explanatory drawing which showed the clearance gap between a vehicle and a side wall. It is the block diagram which showed the structure of the distance measuring device of 4th Example. It is explanatory drawing which showed the measuring method of the curb height. It is the flowchart which showed the processing operation of the distance measuring device of 4th Example. It is the block diagram which showed the structure of the distance measuring device of 5th Example. It is explanatory drawing which showed the measuring method of the width | variety of a side groove. It is the flowchart which showed the processing operation of the distance measuring device of 5th Example. It is the block diagram which showed the structure of the parking assistance apparatus. It is the block diagram which showed the structure of the parking space detection means. (A) It is explanatory drawing which showed the relationship between a vehicle and a parking space, (B) It is explanatory drawing which showed the distance measurement time, (C) It is explanatory drawing which showed the position coordinate of the end point of an obstruction. It is the main flowchart which showed the processing operation of the parking assistance apparatus. It is the flowchart which showed the processing operation of the parking space detection means. It is the flowchart which showed the processing operation of the obstacle relative position acquisition means. (A) It is explanatory drawing which showed the positional relationship of the end point of the obstruction at the time of vehicle reverse, and a vehicle, (B) The explanatory view which showed the end point of the obstruction when a steering wheel was cut, and each ranging area (C) It is explanatory drawing which showed the vehicle state and ranging area just before a vehicle enters into a parking space, (D) It is explanatory drawing which showed the ranging area just before a vehicle enters into a parking space. .

Explanation of symbols

3 Sending means 4 Receiving means 5 Distance detecting means 8 Azimuth angle calculating means 9 Gap distance detecting means D Traveling wave R Reflected wave

Claims (22)

This is a distance measuring method in which a traveling wave is transmitted from a transmitting means, a reflected wave reflected by a measurement object is received by a receiving means, and a gap distance between the center line of the transmitting means and the measurement object is measured. And
Receiving the reflected wave by the wave receiving means, obtaining the target distance from the sending means to the measurement object,
Thereafter, the frequency of the traveling wave is changed, and the gap distance is obtained based on the highest frequency among the reflected waves reflected by the measurement target and the target distance. .   2. The distance measuring method according to claim 1, wherein the amplitude of the traveling wave is changed in accordance with a change in the frequency of the traveling wave.   3. The distance measuring method according to claim 1, wherein when the frequency of the traveling wave is increased, the amplitude of the traveling wave is increased according to the frequency.   The distance measuring method according to claim 3, wherein the amplitude of the traveling wave is set to compensate for atmospheric attenuation at the frequency of the traveling wave.   2. The target distance is determined to be very small when the receiving means receives the reflected wave when the frequency of the traveling wave reaches a predetermined frequency. Ranging method.   A traveling wave having a frequency higher than the traveling wave frequency when the reflected wave reflected by the measurement object is no longer received and larger than the traveling wave amplitude is transmitted from the transmitting means, The distance measuring method according to any one of claims 1 to 5, wherein another measuring object positioned on the center line side from the measuring object is detected. When detecting the other measurement object,
The frequency of the traveling wave is changed, and the amplitude of the traveling wave is changed in accordance with the change of the frequency, and the highest frequency among the reflected waves reflected by the other measurement object is determined from the sending means. The distance measuring method according to claim 6, wherein a gap distance between the center line and the other measurement object is obtained based on the distance to the other measurement object. A distance measuring method for sending a traveling wave from a sending means and receiving a reflected wave reflected by a measuring object by a receiving means to obtain the height of the measuring object,
Sending the traveling wave so that the spread angle of the traveling wave in the horizontal direction is perpendicular to the road surface;
Receiving the reflected wave by the wave receiving means, obtaining the target distance from the sending means to the measurement object,
Measure the gap distance between the center line of the sending means and the upper end of the measurement object by changing the frequency of this traveling wave,
A distance measuring method, wherein the height of the measurement object is obtained based on the gap distance and the object distance.   The distance measuring method according to claim 8, wherein the frequency is changed to increase.   9. The distance measuring method according to claim 8, wherein the frequency is changed so as to be lowered. A traveling wave having an intensity equal to or lower than a predetermined threshold that does not receive the reflected wave from the measurement target is sent from the sending means,
The frequency of the traveling wave is changed, and at this time, the highest frequency among the reflected waves reflected on the road surface and the installation height of the sending means from the road surface in the direction of the center line of the road surface are changed. 9. The distance measuring method according to claim 8, wherein an inclination is obtained to correct a height of the measurement object. A distance measurement method for measuring the width of the concave portion by sending a traveling wave from the sending means toward the concave portion of the road surface and receiving the reflected wave from the concave portion by the receiving means,
A reflected wave that is reflected at the upper end of the outer wall portion of the recess located outside the sending means by changing the amplitude and frequency of a traveling wave having a divergence angle in the vertical direction sent from the sending means; Receiving the reflected wave reflected by the upper end of the inner wall portion of the concave portion located inside the sending means by the receiving means;
The highest frequency among the reflected waves reflected at the upper end of the outer wall portion, the highest frequency among the reflected waves reflected at the upper end of the inner wall portion, the distance between the sending means and the upper end of the outer wall portion, and the sending A distance measuring method, wherein the width of the concave portion is obtained based on the means and the distance to the upper end of the inner wall portion. A sending means for sending a traveling wave, a receiving means for receiving a reflected wave reflected by the measurement object, and an object distance from the sending means to the measurement object when the receiving means receives the reflected wave. A distance measuring device for measuring a gap distance between a center line of the sending means and the measurement object,
Control means for changing the frequency of the traveling wave;
Highest frequency detection means for detecting the highest frequency among the reflected waves reflected by the measurement object;
A distance measuring apparatus comprising: a gap distance calculating means for obtaining the gap distance from the highest frequency detected by the highest frequency detecting means and the target distance. The distance measuring device includes a transmitting means for transmitting a traveling wave and a receiving means for receiving a reflected wave reflected by the measurement target, and obtains the height of the measurement target based on the reception of the reception means. And
Control means for sending the traveling wave having a divergence angle in the vertical direction from the sending means and changing the frequency of the traveling wave;
A target distance calculating means for obtaining a target distance from a change in amplitude of a reflected wave received by the wave receiving means to the measurement target;
A height calculating means for calculating the height of the measurement object,
The control means changes the frequency of the traveling wave,
The height calculation means obtains the height of the measurement object from the highest frequency among the reflected waves reflected by the upper edge of the measurement object received by the wave reception means and the object distance. Ranging device.   15. The distance measuring device according to claim 14, wherein the frequency is changed to increase.   15. The distance measuring device according to claim 14, wherein the frequency is changed so as to be lowered. Ranging that includes a sending means for sending a traveling wave toward a concave portion of a road surface and a receiving means for receiving a reflected wave from the concave portion, and obtaining the width of the concave portion based on the received wave of the receiving means A device,
Control means for changing the amplitude and frequency of a traveling wave having a spread angle in the vertical direction sent from the sending means;
By receiving the reflected wave from the concave portion by the wave receiving means, a first upper end distance from the sending means to the upper end of the outer wall portion of the concave portion, and from the sending means to the upper end portion of the inner wall portion of the concave portion. An upper end distance calculating means for calculating a second upper end distance;
Based on the highest frequency among the reflected waves reflected at the upper end of the outer wall portion, the highest frequency among the reflected waves reflected at the upper end of the inner wall portion, and the first and second upper edge distances, A distance measuring device comprising width calculating means for obtaining a width. A sending means for sending a traveling wave, a receiving means for receiving a reflected wave reflected by the measurement object, and an object distance from the sending means to the measurement object when the receiving means receives the reflected wave. A distance detecting means to be obtained; a control means for changing the frequency of the traveling wave; a highest frequency detecting means for detecting the highest frequency among the reflected waves reflected by the measurement object; and the highest frequency detecting means A parking assistance device having a pair of distance measuring devices having a gap distance calculation means for obtaining the gap distance from the highest frequency and the target distance,
A parking assistance device, comprising: a steering angle calculation means for calculating a steering angle so as to avoid the measurement object based on the gap distance and the target distance obtained by each distance measuring device.   The parking assistance device according to claim 18, wherein the distance measurement area is changed according to the gap distance and the target distance so that the measurement object is located in the distance measurement area.   The parking assistance device according to claim 19, wherein another measurement object is detected in the distance measurement area. A sending means for sending a traveling wave, a receiving means for receiving a reflected wave reflected by the measurement object, and an object distance from the sending means to the measurement object when the receiving means receives the reflected wave. A distance detecting means to be obtained; a control means for changing the frequency of the traveling wave; a highest frequency detecting means for detecting the highest frequency among the reflected waves reflected by the measurement object; and the highest frequency detecting means A distance measuring system provided with distance measuring devices each having a gap distance calculation means for obtaining the gap distance from the highest frequency and the target distance on both sides in the width direction of the moving body,
A distance measuring system characterized in that a path width of the moving body is obtained based on the gap distance obtained by the distance measuring device and a width of the moving body.   The distance measuring system according to claim 21, further comprising: a straight travel propriety determination unit configured to determine whether the moving body can travel straight based on a width of the path.

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