KR20230173812A - Vehicle detector for smart tolling - Google Patents

Abstract

Since the present invention is capable of irradiating light wavelengths over a very wide area on the road, there is no need to use a motor to rotate a laser with a very narrow beam angle. Furthermore, compared to motors that have a short lifespan and frequent breakdowns, it can be used for a long time of more than 100,000 hours. Not only is this possible, but it can also have a vehicle detection angle of more than 45°, which is a smart tooling requirement, so complex algorithm processing is not required. In addition, the price can be significantly reduced by eliminating the use of expensive parts, and the smart toll has excellent performance. It relates to a vehicle detector for a ring, largely comprising: an LED for irradiating a wavelength in an area set as a lane; a condenser lens that condenses the wavelengths of the LED; a lenticular lens that emits surface light using the wavelengths collected by the condenser lens; an optical filter that transmits the wavelengths of the LED reflected and incident from the vehicle while blocking at least the wavelengths in the visible region; a convex lens that condenses the wavelengths transmitted through the optical filter; an avalanche photo diode that receives the wavelength collected by the convex lens; A control unit that detects a vehicle by controlling the LED and the avalanche photodiode in a time of flight (TOF) method.

Description

Vehicle detector for smart tolling}

Since the present invention is capable of irradiating light wavelengths over a very wide area on the road, there is no need to use a motor to rotate a laser with a very narrow beam angle. Furthermore, compared to motors that have a short lifespan and frequent breakdowns, it can be used for a long time of more than 100,000 hours. Not only is this possible, but it can also have a vehicle detection angle of more than 45°, which is a smart tooling requirement, so complex algorithm processing is not required. In addition, the price can be significantly reduced by eliminating the use of expensive parts, and the smart toll has excellent performance. This is about a vehicle detector for Ring.

In general, cars are always jammed at highway toll gates. This is because cars wait one after another to pass through small gates to calculate highway tolls, creating a bottleneck.

To solve this inconvenience, many vehicles equipped with Hi-Pass have appeared, but there is a speed limit of 30 km/h when entering a toll gate for safety reasons, and when changing to the Hi-Pass lane, vehicle crossing occurs and traffic accidents occur due to speed changes. There are still inconveniences that have not been improved, such as road congestion.

As such, the Hi-Pass system currently in operation operates under the concept of a dedicated lane where only Hi-Pass vehicles equipped with a Hi-Pass terminal can pass, and if a general vehicle without a Hi-Pass terminal passes through the Hi-Pass exclusive lane, it is considered a violation. Process it.

However, the smart tolling system operates under the concept that both high-pass vehicles and regular vehicles travel in the same smart tolling lane.

For Hi-Pass vehicles, the same Hi-Pass processing is performed as currently, but for general vehicles, various methods are being prepared to collect toll fees normally.

In this way, the smart tolling system has enhanced license plate recognition and dualization of key control equipment than the Hi-Pass system, and the smart tolling system in terms of toll road operation is an advanced service than the Hi-Pass system.

In the smart tolling system, lane devices can be constructed in the form of single lanes like the current high-pass system in the toll road entrance/exit section, and in the main line section of the toll road, lane devices can be constructed in the form of multiple lanes. Recently, laser scanners have been installed. A vehicle detection method and a smart tolling control method and system using the same have been proposed in Domestic Patent Publication No. 10-1895779.

However, in the case of the vehicle detector using a laser used in the smart tolling control method and system proposed in Domestic Patent Publication No. 10-1895779, a laser with a very narrow beam angle is used, so it is necessary to use a laser using a motor. There is a problem in that the vehicle detector must be rotated.

In addition, the motor used to rotate the vehicle detector using the laser has a short lifespan and frequent breakdowns due to mechanical driving.

In addition, a vehicle detector using a laser can have a wide beam angle of about 190° by driving a motor, but it has the problem of requiring complex algorithm processing as it detects other lanes adjacent to the relevant lane.

Furthermore, vehicle detectors that use a laser that can be rotated by driving a motor have the problem of increasing prices because they require expensive parts.

Domestic Registered Patent Publication Registration No. 10-1895779

The present invention was created to solve the above-mentioned problems. Since it is possible to irradiate light wavelengths over a very large area on the road, there is no need to use a motor to rotate a laser with a very narrow beam angle, and furthermore, it has a short lifespan and is prone to failure. Compared to frequent motors, it can be used for a long period of time (more than 100,000 hours) and can have a vehicle detection angle of more than 45°, which is a smart tooling requirement, so complex algorithm processing is not required. In addition, the price is greatly reduced by eliminating the use of expensive parts. The purpose is to provide a vehicle detector for smart tolling that is capable of doing so and has excellent performance.

The present invention for achieving the above object is a smart tolling vehicle detector installed in a gantry of a road to detect a vehicle passing through the gantry, including an LED for irradiating a wavelength in an area set as a lane; a condenser lens that condenses the wavelengths of the LED; a lenticular lens that emits surface light using the wavelengths collected by the condenser lens; an optical filter that transmits the wavelengths of the LED reflected and incident from the vehicle while blocking at least the wavelengths in the visible region; a convex lens that condenses the wavelengths transmitted through the optical filter; an avalanche photo diode that receives the wavelength collected by the convex lens; A control unit that detects a vehicle by controlling the LED and the avalanche photodiode in a TOF (Time of Flight) method provides a vehicle detector for smart tooling, comprising a.

Here, the LED is preferably made of 940nm LED.

Additionally, the LPI (lines per inch) of the lenticular lens is preferably between 35 LPI and 50 LPI.

Furthermore, the avalanche photo diode is preferably composed of a 16-channel avalanche photo diode (16-channel APD) that receives the wavelength collected by the convex lens by dividing it into 16 zones.

In addition, the LED is disposed in the front lower part of the control unit, the condenser lens is disposed in front of the LED, the lenticular lens is disposed in front of the condenser lens, and the avalanche photo diode is disposed in the front upper part of the control unit. ) is disposed, the convex lens is disposed on the front side of the avalanche photo diode, and the optical filter is disposed on the front side of the convex lens. Inside, the LED, the condenser lens, the lenticular lens, and the light A filter, the convex lens, the avalanche photo diode, and the control unit are provided, and a lower through hole through which the wavelength irradiated by the LED passes is formed at the lower front side, and the wavelength reflected from the vehicle is formed at the upper front side. A vehicle detector for smart tolling, characterized in that it is provided with a case in which the upper through-hole through which the incident occurs is formed.

In addition, it is preferable that the lower front side of the case is stepped toward the rear of the case so that the lower through-hole of the case is located in the rear lower direction of the upper through-hole.

And, a bracket fixed to the front of the control unit inside the case; It is preferable that a lens holder is fixed to the front upper part of the control unit and has a receiving hole for accommodating the convex lens.

The present invention makes it possible to irradiate light wavelengths over a very wide area on the road by emitting the wavelength of the LED onto the road through a lenticular lens, so there is no need to use a motor to rotate the laser with a very narrow beam angle, and furthermore, the lifespan is short. Compared to motors that frequently break down, it can be used for a long period of time (more than 100,000 hours) and can have a vehicle detection angle of more than 45°, which is a smart tooling requirement, so complex algorithm processing is not required. In addition, the price is reduced by eliminating the use of expensive parts. Not only can it save a significant amount by 1/10 compared to other companies, but it also has excellent performance.

Figure 1 is a perspective view schematically showing a vehicle detector for smart tolling, which is an embodiment of the present invention.
Figure 2 is an exploded perspective view of Figure 1;
Figure 3 is a cross-sectional view taken along line A-A of Figure 1;
Figure 4 is a cross-sectional view taken along line B-B in Figure 1;
Figure 5 is a cross-sectional view taken along line C-C of Figure 2 schematically showing the front case;
Figure 6 is a perspective view schematically showing the state in which fixing slits are formed at each corner of the rear case;
Figure 7 is a side view schematically showing a convex lens;
Figure 8 is a front view schematically showing the case installed in the gantry.

Hereinafter, preferred embodiments of the present invention will be described in more detail based on the attached drawings. Of course, the scope of the present invention is not limited to the following examples, and various modifications can be made by those skilled in the art without departing from the technical gist of the present invention.

Figure 1 is a perspective view schematically showing a vehicle detector for smart tolling, which is an embodiment of the present invention, Figure 2 is an exploded perspective view of Figure 1, Figure 3 is a cross-sectional view taken along line A - A of Figure 1, and Figure 4 is a This is a cross-sectional view along line B-B in 1.

As shown in Figures 1 and 2, the vehicle detector for smart tolling, which is an embodiment of the present invention, largely consists of an LED (20), a condenser lens (30), a lenticular lens (40), an optical filter (50), and a convex. It includes a lens (60), an avalanche photo diode (70), and a control unit (80).

First, the LED 20 irradiates a wavelength in the infrared range set to the lane.

850nm and 950nm LEDs can be mainly used as LEDs (20) in the wavelength range mainly used in the infrared region invisible to the human eye. Accordingly, only two wavelengths can be mainly emitted and mass produced depending on the compound when manufacturing IR LEDs. Therefore, it has the advantage of low price.

Among these, when the LED 20 is made of a 940nm LED, the peak light absorption wavelength of the avalanche photodiode 70 can be improved to about 950nm, so the LED 20 is made of a 940nm LED. good night.

Next, the condenser lens 30 condenses the wavelengths of the LED 20 in the infrared range.

In the case of the 940nm LED that can form the LED (20), due to the wide directivity, there is a high risk that the wavelength in the infrared range of the LED (20) will spread outward from the side of the LED (20) and be counted. To prevent this, To this end, the wavelengths in the infrared range of the LED 20 can be condensed through the condenser lens 30 so that the wavelengths in the infrared range of the LED 20 can be easily radiated onto the roadway.

Next, the lenticular lens 40 emits surface light at a wavelength in the infrared range collected by the condenser lens 30.

The lenticular lens 40 is a lens with a fine radius of curvature and a pattern repeatedly formed at a constant pitch. In order to have a beam angle of 45° or more, the LPI (lines per inch) of the lenticular lens 40 is 35 LPI to 35 LPI. 50 LPI is good.

When the LPI (lines per inch) of the lenticular lens 40 is less than 35 LPI, the beam angle of the lenticular lens 40 is so narrow that the surface light emitting area in the lane becomes narrow enough to not cover the lane. There is.

When the LPI (lines per inch) of the lenticular lens 40 is greater than 50 LPI, the beam angle of the lenticular lens 40 may be larger, but the wavelength intensity and irradiation distance in the infrared range of the LED 20 are There is a problem in that the light receiving efficiency of the avalanche photodiode 70 also decreases.

In order to more easily surface emit a wavelength in the infrared range through the lenticular lens 40, it is better that the LPI (lines per inch) of the lenticular lens 40 is particularly 40 LPI.

Next, the optical filter 50 blocks wavelengths in the visible region of at least 850 nm or less while transmitting the wavelengths in the infrared region of the LED 20 that are reflected and incident from a vehicle traveling on the lane.

The optical filter 50 may be made of a band pass filter or a visible cut filter.

Here, the band pass filter that can form the optical filter 50 is a filter through which only specific wavelengths such as 950 nm ± 20 nm pass, and can block outdoor sunlight more effectively, but is expensive. And because the full width at half maximum (FWHM) of the LED is wide, there is a problem in that the signal area is partially blocked, shortening the measurement distance.

Accordingly, the optical filter 50 is made of a low-cost visible cut filter that blocks the visible region between 0 nm and 850 nm to suppress disturbance light noise caused by sunlight outdoors. It is more desirable.

Next, the convex lens 60 focuses the wavelengths in the infrared range of the LED 20 that have passed through the optical filter 50 so that they can be easily incident on the avalanche photodiode 70.

Next, the avalanche photodiode 70 receives the wavelength in the infrared range of the LED 20 condensed by the convex lens 60.

The avalanche photodiode 70 may be made of various types, and in particular, it is preferably made of a 16-channel avalanche photodiode (16ch APD) that receives signals divided into 16 zones.

For that reason, the 16-channel avalanche photodiode (16ch APD), which can form the avalanche photodiode 70, has a gain of more than 100 times that of a general photodiode, making it advantageous for measuring finer signals, In the case of the 940nm LED having a surface emission form that can form the LED (20), the light signal is weaker than that of the laser, so the fine light signal of the 940nm LED that can form the LED (20) is transmitted through the avalanche photodiode (70). ) In order to easily receive and measure light, the abalance photodiode 70 is preferably a 16-channel avalanche photodiode (16ch APD).

In particular, the reason why the avalanche photodiode 70, which can be made of a 16-channel avalanche photodiode (16ch APD), was manufactured with 16 channels (ch) is that when detecting a vehicle in a 6m gantry, 30cm per channel can be detected. The width of one lane on a highway is approximately 3.6m, and for 1.5 lanes, it is approximately 4.9m.

The vehicle detector product for smart tooling of the present invention is installed in each lane. One product detects 1.5 lanes, and this is to detect vehicles changing lanes on the highway.

Usually, the channel array uses 1 channel, 4 channels, 8 channels, 16 channels, and 32 channels. This is determined depending on the input channel of the TDC (time to digital converter) IC. When 8 channels are used, 60 cm is detected per channel. When a vehicle is driving at high speed (100 km/h) on the highway and the vehicle detector detects at a sampling rate of 200khz, the vehicle moves 30cm from the first detection to the next detection, so the 16 channels as the avalanche photodiode 70 When using an avalanche photodiode (16ch APD), movement of one channel is detected per sampling, enabling effective detection even when the vehicle changes lanes.

Next, the control unit 80 may intermittently control the LED 20 and the avalanche photodiode 70 in a TOF (Time of Flight) method at certain time intervals.

The control unit 80 may be made of various types, such as a printed circuit board (PCB).

The control unit 80 can detect the vehicle while calculating the location and distance of the vehicle using the wavelength received by the avalanche photodiode 70. Since this is a known matter, detailed description will be omitted below. .

Next, as shown in FIGS. 1 to 4, the LED 20, the condenser lens 30, the lenticular lens 40, the optical filter 50, the convex lens 60, and the avalanche photo. A case 10 may be provided in which the diode 70 and the control unit 80 are provided.

The LEDs 20 may be disposed at regular intervals from one side of the control unit 80 to the other side of the control unit 80 provided inside the case 10 .

With the condenser lens 30 disposed on the front side of the LED 20, the condenser lens 30 may be fixed to the front lower part of the control unit 80 in various ways, such as by bolting, The LED 20 may be accommodated inside the condenser lens 30.

The lenticular lens 40 may be disposed in front of the condenser lens 30.

The avalanche photodiode 70 may be disposed on the upper front side of the control unit 80.

The convex lens 60 may be disposed in front of the avalanche photodiode 70.

The optical filter 50 may be disposed in front of the convex lens 60.

It is preferable that the optical filter 50 is provided on the inner upper side of the case 10 so as to be located at least in front of the convex lens 60. However, the optical filter 50 is located on the front and rear sides of the convex lens 60. Of course, it can also be provided on both the upper and lower inner sides of the case 10 so as to be located in front of the lenticular lens 40, respectively.

A lower penetration hole 124 may be formed in the front lower part of the case 10 through which wavelengths in the infrared range irradiated by the LED 20 pass.

An upper through-hole 123 may be formed in the front upper part of the case 10 through which wavelengths in the infrared range of the LED 20 reflected from the vehicle are incident.

Figure 5 is a cross-sectional view taken along line C-C of Figure 2 schematically showing the front case.

For example, the case 10 may be largely composed of a rear case 110 and a front case 120, as shown in FIGS. 1 to 5.

Inside the rear case 110, the LED 20, the condenser lens 30, the lenticular lens 40, the optical filter 50, the convex lens 60, and the avalanche photodiode (70) ) and the control unit 80 can be accommodated in various ways, such as bolt fixation.

The front side of the rear case 110 may be open.

Fixing holes 111 may be formed at each rear corner of the rear case 110.

Figure 6 is a perspective view schematically showing a state in which fixing slits are formed at each corner of the rear case.

Alternatively, fixed slits 112 may be formed at each rear corner of the rear case 110, extending left and right at a certain length from one side of the rear case 110 to the other side, as shown in FIG. 6.

Among the fixing slits 112 of the rear case 110, one side of the fixing slit 112 located on one side of the rear case 110 may be open.

Also, the other side of the fixing slit 112 of the rear case 110 located on the other side of the rear case 110 may be open.

A fitting groove 113 extending along the front edge of the rear case 110 may be formed at the front edge of the rear case 110.

In order to improve the airtightness and watertightness of the case 10, which may include the rear case 110 and the front case 120, the fitting groove 112 has a shape corresponding to the fitting groove 112. The packing member 114 may be detachably fitted.

The packing member 114 may be made of various types, such as an O-ring made of rubber.

Next, the front case 120 is detachably provided on the front side of the rear case 110 in various ways, such as by bolting, so that the front side of the rear case 110 can be opened and closed.

The rear side of the front case 120 may be open.

On the front side of the front case 120, upper through-holes 123 and lower through-holes 124 may be formed at regular intervals in the vertical direction of the front case 120.

For example, the front case 120 may largely include an upper front case 121 and a lower front case 122, as shown in FIGS. 2 and 5.

The upper through-hole 123 may be formed in the lower middle portion of the upper front case 121.

The lower through-hole 124 may be formed in the upper middle portion of the lower front case 122.

The lower front side of the front case 120 of the case 10 is positioned so that the lower through-hole 124 of the case 10 is located in the rear lower direction of the upper through-hole 123. A step may be formed in a '┓' shape in the rearward direction of (120), indented to a certain depth.

As a result, a step surface 125 perpendicular to the front of the lower front case 122 on the lower surface of the upper front case 121 extends left and right at a certain length from one side of the upper front case 121 to the other side. can be formed.

The wavelength in the infrared range of the LED 20 may pass through the lower penetration hole 124 and be irradiated to the roadway in the outer direction of the case 10. Wavelengths in the infrared range may be reflected by a sensing object, such as a vehicle, and be received by the avalanche photodiode 70 while passing through the upper through hole 123.

Here, a part of the wavelength in the infrared range irradiated to the roadway in the outer direction of the case 10 through the lower penetration hole 124 and a part of the wavelength in the infrared range diffusely reflected inside the case 10 are shown in FIG. 5. As can be seen, because it can be reflected on the step surface 125 (see the dotted arrow in FIG. 5), some of the wavelengths in the infrared range irradiated to the outside of the case 10 and diffusely reflected inside the case 10. It is possible to more efficiently prevent part of the wavelengths in the infrared range from being incident on the upper through-hole 123.

As shown in FIGS. 2 to 4, a bracket 11 may be vertically installed inside the rear case 110 of the case 10.

One side and the other side of the bracket 11 may be detachably provided in various ways, such as fixing with bolts to one inner side and the other inner side of the front case 120 of the case 10, respectively.

The control unit 80 can be vertically fixed to the front of the bracket 11 in a detachable manner using various methods such as bolt fixation.

Figure 7 is a side view schematically showing a convex lens.

Next, the wavelength in the infrared region reflected from a detection object such as a vehicle, incident on the convex lens 60 at an angle of 45°, and collected through the convex lens 60 is viewed by the avalanche photodiode 70. In order to facilitate incident light, as shown in FIG. 7, the front side of the convex lens 60 is made of an aspherical surface (AS) that is convex in the front direction of the convex lens 60, and the convex lens 60 The rear side may be made of a spherical surface (SS) that is convex toward the rear of the convex lens 60.

In particular, in order to allow the wavelengths in the infrared range condensed through the convex lens 60 to more easily enter the avalanche photodiode 70, the front side of the convex lens 60, which is aspherical (AS), The radius of curvature R is 12.2022, and the radius of curvature R at the rear of the spherical (SS) convex lens 60 is preferably 14.0705.

The convex lens 60 can be positioned and fixed on the upper front side of the control unit 80, and a lens holder 12 is provided to easily position the convex lens 60 on the upper front side of the control unit 80. It can be provided.

For example, the lens holder 12 may be composed of a plate-shaped holder body 12a and a tubular auxiliary holder body 12b.

Each corner of the plate-shaped holder body 12a can be fixed to the front upper part of the control unit 80 in various ways, such as by bolting.

A receiving hole (12c) may be eccentrically formed in the plate-shaped holder body (12a), and the avalanche photodiode (70) may be disposed in the receiving hole (12c).

The rear side, which is opposite to the front side of the tubular auxiliary holder body 12b, can be detachably fixed to the receiving port 12c of the plate-shaped holder body 12a in various ways, such as press fit.

The convex lens 60 may be vertically installed inside the rear side of the tubular auxiliary holder body 12b.

The avalanche photodiode 70 may be provided on the upper front side of the control unit 80 and placed in the receiving hole 12c of the lens holder 12.

Figure 8 is a front view schematically showing the case installed in the gantry.

Next, the case 10 is laid horizontally so that the upper through hole 123 and the lower through hole 124 of the case 10 face the lane, and a traffic signal or road light is installed as shown in FIG. 8. It can be provided on the bottom of the girder (3a) provided at a certain height on the top of the gantry (3), which is a gate-type structure used to support traffic safety facilities such as signs.

A plurality of cases 10 may be provided on the bottom of the girder 3a of the gantry 3 at regular intervals from one side to the other side of the gantry 3.

The case 10 is a bolt screwed to the bottom of the girder 3a of the cantry 3 at a certain depth while vertically penetrating the fixing hole 111 or the fixing slit 112 of the case 10. It can be detachably fixed to the bottom surface of the girder 3a of the gantry 3 by fastening members such as the like.

The present invention, constructed as described above, emits surface light of the wavelength of the LED 20 onto the lane through the lenticular lens 40, making it possible to irradiate the light wavelength over a very wide area on the lane, thereby rotating the laser with a very narrow beam angle. There is no need to use a motor for this purpose, and furthermore, it can be used for a long time of more than 100,000 hours compared to motors with a short lifespan and frequent breakdowns, and has a vehicle detection angle of more than 45° (see α in Figure 8), which is a smart tooling requirement. There is no need for complex algorithmic processing, and by eliminating the use of expensive parts, the price can be drastically reduced to 1/10 compared to other companies, as well as providing excellent performance.

20; LED, 30; condenser lens,
40; lenticular lens, 50; optical filter,
60; convex lens, 70; avalanche photodiode,
80; Control unit.

Claims (7)

In the smart tolling vehicle detector that is installed on the gantry of the road and detects vehicles passing through the gantry,
LEDs for irradiating wavelengths in the area set as a lane;
a condenser lens that condenses the wavelengths of the LED;
a lenticular lens that emits surface light using the wavelengths collected by the condenser lens;
an optical filter that transmits the wavelengths of the LED reflected and incident from the vehicle while blocking at least the wavelengths in the visible region;
a convex lens that condenses the wavelengths transmitted through the optical filter;
an avalanche photo diode that receives the wavelength collected by the convex lens;
A vehicle detector for smart tooling, comprising a control unit that detects a vehicle by controlling the LED and the avalanche photodiode in a TOF (Time of Flight) method.
According to clause 1,
The LED is a vehicle sensor for smart tooling, characterized in that it is made of 940nm LED.
According to clause 1,
A vehicle detector for smart tooling, characterized in that the LPI (lines per inch) of the lenticular lens is 35 LPI to 50 LPI.
According to clause 1,
The Avalanche Photo Diode is a smart tolling vehicle detector, characterized in that it consists of a 16-channel APD that receives the wavelength collected by the convex lens by dividing it into 16 zones.
According to clause 1,
The LED is disposed in the front lower part of the control unit, the condenser lens is disposed in front of the LED, the lenticular lens is disposed in front of the condenser lens, and the avalanche photo diode is disposed in the front upper part of the control unit. Arrangement, the convex lens is disposed on the front side of the avalanche photo diode, and the optical filter is disposed on the front side of the convex lens; The convex lens, the avalanche photo diode, and the control unit are provided, and a lower through hole through which the wavelength irradiated by the LED passes is formed at the lower front side, and the wavelength reflected from the vehicle is incident at the upper front side. A vehicle detector for smart tolling, characterized in that it is provided with a case in which an upper through hole is formed.
According to clause 5,
A vehicle detector for smart tolling, characterized in that a step is formed in a state in which the lower front side of the case is recessed toward the rear of the case so that the lower through-hole of the case is located in the rear lower direction of the upper through-hole.
According to clause 5,
a bracket fixed to the front of the control unit inside the case;
A vehicle detector for smart tolling, characterized in that it is provided with a lens holder that is fixed to the front upper part of the control unit and has a receiving hole for accommodating the convex lens.