TW202319633A - Anti-pinch detection device for bus doors - Google Patents

Abstract

An anti-pinch detection device for bus doors includes a processor, a radio frequency generator, a power amplifier, a radio frequency transceiver module, and an analog-digital converter. The processor provides timing control signals and performs an anti-pinch detection. The radio frequency generator generates a first FMCW signal from the timing control signal. The power amplifier amplifies the first FMCW signal. The radio frequency transceiver module transmits the first FMCW signal with a half-power beam width of 40 ^o×20 ^oto a target area and receives a reflected second FMCW signal and generates a beat frequency signal. The analog-digital converter converts the beat frequency signal into data and transmits the data to the processor, so that the processor performs the anti-pinch detection according to the data to determine whether there are passengers or objects in the target area. The target area is a space covering the inside and outside of the bus door for the passengers to get on and get off.

Description

Anti-pinch detection device for bus doors

The invention relates to a microwave radar detection technology, in particular to an anti-pinch detection device for a bus door.

The current method of anti-pinch detection and warning system for bus doors is usually to draw a "no standing zone" (KEEP CLEAR) on the door, install an in-car broadcaster, and provide the driver with a voice to remind passengers not to stand in the forbidden zone. When the driver controls the opening and closing of the door, the warning voice, sound and flashing light will be issued first, and the driver will be monitored by the right rearview mirror; if there is a video monitor installed in the car, the driver can watch the door getting on and off the car area from the monitoring screen , then open and close the door.

Drivers can use video to monitor passengers getting on and off the car, but video monitors are more susceptible to weather (such as rain, fog) and light. If infrared detectors or ultrasonic detectors are used, they are easily affected by climate factors such as temperature differences or strong winds, while LiDAR is expensive.

In the anti-pinch detection of the current bus door, the driver must concentrate on monitoring the screen or look at the rear mirror. It is very likely that due to factors such as negligence, too many passengers, or complicated road conditions, you will not be able to concentrate, and then the accident that the door will pinch passengers or objects occurs.

Another anti-pinch detection method is to install a contact type anti-pinch detection device on the bus, and install an air pressure anti-pinch detection sensor tube on the door frame. If the door is caught by a passenger or cannot be closed properly, the door will automatically open. Continuously emit a warning sound to remind the driver, thereby ensuring the safety of passengers getting on and off the car. The disadvantage is that after a period of use, the sensitivity of the contact part of the anti-pinch detection sensing tube may be uneven, or the door cannot be opened normally due to insufficient air pressure. Passengers may be caught. At the same time, when the contact sensor is in operation, the passengers are easily frightened, and the intuitive reflex action may cause harm to the passengers themselves or cause harm to other passengers.

Therefore, it is necessary to provide an improved anti-pinch detection device for coach doors that utilizes microwave signals to monitor the area of getting on and off the car door, so as to solve the problems existing in the conventional technology.

The motivation of the present invention is to provide an anti-pinch detection device for the door of a bus, aiming to solve and improve the problems and shortcomings of the aforementioned prior art.

The main purpose of the present invention is to provide an anti-pinch detection device for the door of a bus, which can detect Whether there are passengers or objects in the boarding and exiting spaces inside and outside the doors of the bus can effectively ensure that accidents such as human body or objects will not be caught when the driver controls the closing of the doors, thereby achieving the effect of truly improving safety.

Another main purpose of the present invention is to provide an anti-pinch detection device for the bus door, which is installed above the bus door to illuminate the target area covered by passengers getting on and off the bus from top to bottom. When the door is opened, it detects whether the target area is occupied. If the target area is occupied, it means that the passengers get on or off the bus.

Another main purpose of the present invention is to provide an anti-pinch detection device for bus doors, which has the ability to detect large objects/small objects (such as adults, children, umbrellas, bags), and is capable of detecting small objects , use the mechanism of delay time as a reinforcement in the design.

Another main purpose of the present invention is to provide an anti-pinch detection device for a bus door, which focuses on fast response time, high detection rate and low false alarm rate in design.

In order to achieve the above-mentioned purpose, the present invention provides an anti-pinch detection device for a large bus door, including: a processor, which provides a timing control signal and performs anti-pinch detection; a radio frequency generator, and the processor Electrically connected to generate a first FM continuous wave signal from the timing control signal; a power amplifier electrically connected to the radio frequency generator to amplify the first FM continuous wave signal; a radio frequency transceiver module, Electrically connected with the power amplifier for transmitting the first FM continuous wave signal to a target area and receiving a second FM continuous wave signal reflected by the target area, and generating the first FM continuous wave signal and the second FM continuous wave signal A difference frequency signal of an FM continuous wave signal; and an analog-to-digital converter electrically connected to the radio frequency transceiver module and the processor for converting the difference frequency signal into a data and sending the data to the processor, so that the processor performs the anti-pinch detection according to the data, and judges whether there are passengers or objects in the target area; wherein, the half-power beamwidth of the first FM continuous wave signal transmitted by the radio frequency transceiver module is 40 ^o × 20 ^o , and the target area is a boarding and disembarking space covering the inside and outside of the bus door.

In one embodiment of the present invention, the anti-pinch detection device further includes a communication and power supply unit, wherein the communication and power supply unit is electrically connected to the processor and provides an interface with a vehicle power supply, and when the anti-pinch When the result of the detection judges that there are passengers or objects in the target area, the communication and power supply unit transmits an anti-pinch message to a driving console.

In one embodiment of the present invention, the radio frequency transceiver module includes a coupler, a filter, a transmitting antenna, a low noise amplifier, a receiving antenna, a mixer and an intermediate frequency amplifier, wherein the coupler distributing the first FM continuous wave signal amplified by the power amplifier to the filter, the mixer and the intermediate frequency amplifier, and the transmitting antenna transmits the first FM continuous wave signal filtered by the filter to the target area, the receiving antenna receives the second FM continuous wave signal reflected by the target area, the low noise amplifier amplifies the second FM continuous wave signal with low noise, and the mixer and intermediate frequency amplifier amplify the second FM continuous wave signal An FM continuous wave signal and the second FM continuous wave signal are mixed and filtered to generate the difference frequency signal.

Further, the coupler is electrically connected to the power amplifier, the transmitting antenna is electrically connected to the filter, the receiving antenna is electrically connected to the low noise amplifier, and the mixer and the intermediate frequency amplifier are electrically connected to the low noise amplifier. The noise amplifier and the analog-to-digital converter are electrically connected.

Further, at least the receiving antenna and the transmitting antenna are arranged above the outer side of the bus door, and the receiving antenna and the transmitting antenna have a shortest detection distance and a furthest detection distance in the vertical direction towards the ground . In one embodiment, the shortest detection distance is 0.3 to 0.7 meters, and the farthest detection distance is 1 to 2.2 meters.

In one embodiment of the present invention, the processor includes a preprocessing unit, a fast Fourier transform unit, a clutter removal unit, a binary integral detection unit, and a state output unit, and the preprocessing unit processes the data and correct the outliers in the data, the fast Fourier transform unit receives the processed data, executes the Hamming window function, and performs fast Fourier transform to obtain a one-dimensional frequency spectrum, the clutter removal unit extracting a background spectrum of the target area, and then subtracting the background spectrum from the one-dimensional spectrum to obtain a sampled spectrum and providing it to the binary integral detection unit, and the binary integral detection unit executes on the sampled spectrum A binary integral detection is used to obtain a detection state, and the state output unit outputs according to the detection state.

Further, the binary integral detection is an M-out-of-N detection, where N is the number of frames set, and M is the number of frames of the target object obtained by setting the detection. In addition, when a total value of the binary integral detection is 0, the detection state is a first state, and the state output unit outputs a signal of logic 0; when the binary integral detection starts counting, The total value is greater than 0 and less than M, the detection state is a second state, and the state output unit outputs a clock wave of logic 0 and 1 alternately; and when the total value detected by the binary integral is greater than or equal to M, the detection state is a third state, and the state output unit outputs a signal of logic 1.

In one embodiment of the present invention, the anti-pinch detection device further includes a cylindrical body, wherein the processor, the radio frequency generator, the power amplifier, the radio frequency transceiver module and the analog-to-digital converter are arranged on the In the cylindrical body, the radius of the cylindrical body is 3.5 cm, and the height of the cylindrical body is 11 cm. The length of one body of the passenger car door is 7 centimeters.

Compared with the conventional technology, the present invention installs a door anti-pinch detection device on the top of the car door to detect whether a human body or object is caught during the closing process of the car door by transmitting microwave signals, receiving trace signals and performing signal processing. Accidents, which are non-contact sensors, have the effect of improving passenger safety and reassuring passengers.

In order to make the above and other objects, features, and advantages of the present invention more comprehensible, preferred embodiments of the present invention will be exemplified below in detail together with the attached drawings. Furthermore, the directional terms mentioned in the present invention are, for example, up, down, top, bottom, front, back, left, right, inside, outside, side, surrounding, central, horizontal, transverse, vertical, longitudinal, axial, The radial direction, the uppermost layer or the lowermost layer, etc. are only directions referring to the attached drawings. Therefore, the directional terms used are used to illustrate and understand the present invention, but not to limit the present invention.

Please refer to FIG. 1, which shows a block diagram of an anti-pinch detection device according to an embodiment of the present case. As shown in FIG. 1 , according to one embodiment of the present case, the anti-pinch detection device 100 is used in a bus door. The anti-trap detection device 100 includes a processor 110 , a radio frequency generator 120 , a power amplifier 130 , a radio frequency transceiver module 140 and an analog-to-digital converter 150 . The processor 110 provides timing control signals and performs anti-pinch detection. The radio frequency generator 120 is electrically connected with the processor 110 and is used for generating a first FM continuous wave signal from the timing control signal. The power amplifier 130 is electrically connected to the radio frequency generator 120 for amplifying the first FM continuous wave signal to eg 1 mW. The radio frequency transceiver module 140 is electrically connected with the power amplifier 130 for transmitting the first FM continuous wave signal to the target area and receiving the second FM continuous wave signal reflected by the target area, and generating the first FM continuous wave signal and the second FM continuous wave signal Difference frequency signal of continuous wave signal. The analog-to-digital converter 150 is electrically connected with the radio frequency transceiver module 140 and the processor 110 to convert the difference frequency signal into data, and transmit the data to the processor 110, so that the processor 110 performs anti-pinch detection according to the data , to determine whether there are passengers or items in the target area. Among them, the half-power beam width of the first FM continuous wave signal transmitted by the radio frequency transceiver module 140 is 40 ^° ×20 ^° , and the target area is the boarding and disembarking space covering the inside and outside of the bus door.

In some embodiments, the anti-pinch detection device 100 of the present application further includes a communication and power supply unit 160 . The communication and power supply unit 160 is electrically connected with the processor 110 and provides an interface with the vehicle power supply, and when the judging result of the anti-pinch detection determines that there are passengers or objects in the target area, the communication and power supply unit 160 transmits the anti-pinch message to the driver Console 170.

In some embodiments, the RF transceiver module 140 includes a coupler 141 , a filter 142 , a transmit antenna 143 , a receive antenna 144 , a low noise amplifier 145 , and a mixer and IF amplifier 146 . The coupler 141 distributes the first FM continuous wave signal amplified by the power amplifier 130 to the filter 142 and the mixer and IF amplifier 146 . The transmitting antenna 143 transmits the first FM continuous wave signal filtered by the filter 142 to the target area. The receiving antenna 144 receives the second FM continuous wave signal reflected by the target area. The low noise amplifier 145 amplifies the low noise of the second FM continuous wave signal, and the mixer and intermediate frequency amplifier 146 mixes and filters the first FM continuous wave signal and the second FM continuous wave signal, and generates a difference frequency signal . Preferably, the coupler 141 is electrically connected to the power amplifier 130, the transmitting antenna 143 is electrically connected to the filter 142, the receiving antenna 144 is electrically connected to the low noise amplifier 145, and the mixer and the intermediate frequency amplifier 146 are electrically connected to the low noise amplifier 146. The noise amplifier 145 and the analog-to-digital converter 150 are electrically connected, but they are not limited thereto.

)並接收由目標區域所反射的回跡訊號頻率(

)，兩者經混波處理後得到相差的頻率即差頻(

)，可用以估計目標物的距離 ，算式如下列方程式(a)與方程式(b)。

(a)

(b) Please refer to Figure 2 and cooperate with Figure 1, wherein Figure 2 shows the frequency-time correspondence diagram of the transmission signal, return signal and their phase difference of an anti-pinch detection device according to an embodiment of the present case. As shown in Figures 1 and 2, the anti-pinch detection device 100 of this case uses frequency-modulated continuous wave (FMCW) technology to transmit FMCW to the target area and receive its target echo (echo), and the received echo After the signal is processed, the distance parameters of the target (person, object, etc.) are obtained. The anti-pinch detection device 100 transmits the signal frequency (

) and receive the echo signal frequency reflected by the target area (

), the frequency difference between the two after wave mixing processing is the difference frequency (

), which can be used to estimate the distance of the target object, the calculation formula is as follows equation (a) and equation (b).

(a)

(b)

為回跡訊號與發射訊號的差頻，

為入侵物與雷達的距離，

是調頻連續波發射訊號的掃描頻寬，

是調頻連續波發射訊號的掃描週期，

為光的速度。 in,

is the difference frequency between the trace signal and the transmit signal,

is the distance between the intruder and the radar,

is the scanning bandwidth of the FM continuous wave transmitting signal,

is the scanning period of the FM continuous wave transmitting signal,

for the speed of light.

Please refer to FIG. 3 , which is a schematic diagram showing the coverage of the antenna of an anti-pinch detection device according to an embodiment of the present case. As shown in Figure 3, when the anti-pinch detection device in this case is erected, the origin of the XYZ three-axis coordinates is the center point of the antenna of the anti-pinch detection device, and the half-power beam of the antenna after the anti-pinch detection device is erected The width is ^40o × ^20o , but it is not limited to this, and the target area covered is the boarding and disembarking space inside and outside the door of the bus.

Please refer to FIG. 4 and cooperate with FIG. 1, wherein FIG. 4 shows a block diagram of a processor of an anti-pinch detection device according to an embodiment of the present case. As shown in Figure 1 and Figure 4, the processor 110 of the anti-pinch detection device 100 of this case includes a preprocessing unit 1101, a fast Fourier transform (FFT) unit 1102, a clutter removal unit 1103, and a binary integral detection unit 1104 and status output unit 1105 . The pre-processing unit 1101 performs processing on the data output by the analog-to-digital converter 150 to correct outliers in the data. Then the data is input into the FFT unit 1102, and the FFT unit 1102 executes the Hamming window function (Hamming window), and then performs FFT to obtain a one-dimensional frequency spectrum. The clutter removal unit 1103 extracts the background spectrum of the target area, and then subtracts the background spectrum from the one-dimensional spectrum to obtain the sampled spectrum and provides the sampled spectrum to the binary integral detection unit 1104; the binary integral detection unit 1104 detects the clutter The sample spectrum provided by the wave removal unit 1103 performs binary integral detection to obtain the detection state, and the state output unit 1105 outputs according to the detection state.

In some embodiments, the binary integral detection is a detection of M out of N, that is, an M-of-N detection, where N is the number of frames to be set, and M is the target obtained from the set detection. The number of boxes for objects. M-Of-N means that if the target is detected in M frames among the consecutive N frames, it is determined that the target exists. The detection result of the anti-pinch detection device 100 in this case is a binary state event, and the result is 1 or 0. The result is 1, indicating that the space is occupied; the result is 0, indicating that the space is not occupied. M is a configurable integer value.

In some embodiments, the state output unit 1105 is electrically connected to the binary integration detection unit 1104. Once the binary integration detection unit 1104 is activated, the state output unit 1105 outputs positive and negative alternating clock waves. When the binary integration condition is established (eg M out of N is completed), the state output unit 1105 outputs a signal of logic 1, that is, the space is occupied.

Please refer to Figure 5 (A) and Figure 5 (B) together with Figure 4, which shows that an anti-trap detection device in an embodiment of this case shows the removal of clutter, the nearest Schematic diagram of detection distance and maximum detection distance. As shown in Figure 4, Figure 5 (A) and Figure 5 (B), the clutter removal unit 1103 arranges a measurement time in an environment without targets, transmits a specific continuous wave, receives and processes it, and Subtract the specific continuous wave spectral line from the spectrum to obtain the background clutter, set the reference value as shown in Figure 5 (B), and then subtract the background clutter from the detected spectrum, and at the same time, according to the set shortest detection distance R _min and the farthest detection distance R _max remove the spectral lines that are smaller than the shortest detection distance and greater than the farthest detection distance, as shown by the dotted line, such as area C in Figure 5 (A).

The purpose of using binary integral detection (M-Of-N detection) is to maintain a high detection rate and a very low false alarm rate of the anti-pinch detection device, and to avoid a too low detection rate, that is, the space is occupied and the It is judged as unoccupied, or the false alarm rate is too high, that is, the space is judged as occupied because it is not occupied. Its logic is that among N consecutive detections, if there are more than M times true, then it is true.

)與誤警率(

)以下列方程式(c)至(e)表示，其中

為單次偵測的偵測率，

為單次偵測的誤警率。

Further explain the design considerations of the simulated experiment using binary integral detection (M-Of-N detection) as follows: N involves the response time of the anti-trap detection device, if the design is to report a detection result in 1 second, in 1 Perform 10 detections (including transmission, reception and processing) within 1 second, N=10. According to relevant data, under different reflection characteristic conditions (Swerling 0 to Swerling IV), its M can be selected from any one of 3 to 6, so it is more conservative to choose M=6; M-Of-N detection output detection measurement rate (

) and false alarm rate (

) are expressed by the following equations (c) to (e), where

is the detection rate of a single detection,

is the false alarm rate of a single detection.

= 0.8000，

= 0.0100, N=10，M=6，則M-Of-N偵測得到

=0.9672，

=

，故M-Of-N的偵測率及誤警率皆符合要求。 Taking the simulation experiment as an example, assuming that the signal-to-noise ratio SNR=9dB,

= 0.8000,

= 0.0100, N=10, M=6, then M-Of-N can be detected

=0.9672,

=

, so the detection rate and false alarm rate of M-Of-N meet the requirements.

Please refer to FIG. 6, which shows the workflow of the binary integral detection unit of an anti-pinch detection device according to an embodiment of the present case. As shown in Figure 6, the workflow of the binary integral detection unit of the anti-pinch detection device includes the following parts:

(A) Compare the size of the sampling spectrum with the set threshold value. If any frequency signal (spectral line) in the sampling spectrum exceeds the threshold value, that is, the absolute value of the fast Fourier transform (FFT) is greater than or equal to the threshold value (Thres), Then the basic detection bit pri_det = 1, otherwise the basic detection bit pri_det = 0, and the basic detection bit is output to a one-dimensional N-bit right shift buffer.

(B) The basic detection bit is input from the left end of the right shift buffer by the N bit, and each cycle T ₁ (the time when the anti-pinch detection device works once) is shifted to the right by one bit, and the The sum of N bits shifting the buffer to the right, that is, summing up the latest N bits to obtain the sum value (sum), as shown in the following equation (f): sum(i) = pri_det(i) + pri_det (i-1) + ... + pri_det(iN-1) (f)

(C) State judgment, if the total value = 0, it is the first state (state = I); if 0 < total value < M, then it is the second state (state = J); if the total value ≧ M , then it is the third state (state = K).

The detection state defined by the anti-pinch detection device in this case has at least three states. Among them, the first state I represents the initial state, and its specific action is that the driver initiates the action of closing the door, and the total value at this time=0; if 0<total value<M, then enter the second state J, indicating that someone gets on the car or Get off the bus; when the total value≧M, enter the third state K, which means someone is waiting (the space is occupied).

Please refer to Figure 1, Figure 4 and Figure 6 again. The state output unit 1105 outputs a binary signal according to the detection procedure of the binary integral detection unit 1104. In the initial state (total value=0), the state output unit 1105 obtains a logic 0 signal and outputs a logic 0 signal. Once the total value is greater than 0 and less than M (0<total value<M), the state output unit 1105 outputs a clock wave of logic 0 and 1 alternately, so that the display light of the driving console 170 starts to flash; when M-of- The N condition is met, and M is selected from N (total value≧M), the state output unit 1105 receives a logic 1 signal, plus a delay time of 0.5 seconds, and outputs a logic 1 signal to the driving console 170 to make the display light long Bright. In other words, the anti-pinch detection device in this case can be provided with a display light on the driving console 170 . If the indicator light is not on, it means that there is no one in the detection area; if the indicator light is flashing, it means that someone is getting on or off the vehicle in the detection area; if the indicator light is on, it means that there is someone in the detection area. When necessary, sound can be added to remind the driver.

The detection distance range of the anti-pinch detection device 100 is less than 2 meters, and the distance resolution must be properly set to have a suitable dynamic range, so that the detection device can adapt to changes in the distance of the target object. And counting the detection results, for example, the dynamic range is 16dB.

Please refer to FIG. 7, which shows a control sequence diagram of an anti-pinch detection device according to an embodiment of the present case. As shown in Fig. 7, T _ref is the background detection time of the anti-pinch detection device, enable background detection, transmit a specific continuous wave, receive and process, obtain the background spectrum, and use the subsequent spectrum to delete the background. T ₁ is the time for the anti-pinch detection device to work once, and T ₂ is the time for toilet preparation to complete the setting of processing parameters. T ₃ is the enabling time of the power amplifier. T ₄ is the working time of the anti-pinch detection device, including the execution of transmitting-FM continuous wave, receiving and processing. T ₁ =T ₂ +T ₄ . T ₅ is the time of continuous detection, the default time of T ₅ is 10 times of T ₁ , if T ₁ is preset to 0.1 second, set T _ref =T ₁ , and arrange 1 background detection followed by 10 normal The working time, then a detection task cycle time T _C is slightly equal to 1.1 seconds, the equation is as follows: T _C = T _ref +10T ₁ = 11T ₁ (g)

But not limited to this. In practice, in response to different background clutter and the speed of passengers getting on and off the bus, it is possible to adjust the mode of one background detection followed by continuous detection.

Please refer to Figure 1 and Figure 7 again. The control timing of the anti-pinch detection device 100 in this case is the control signal generated by the processor 110 . The sawtooth wave system of enabling time _T3 in the 7th figure provides the radio frequency generator 120, makes the radio frequency generator 120 generate the first FM continuous wave, through the power amplifier 130, the coupler 141, the filter 142, until the transmitting antenna 143 Transmit the first FM continuous wave signal. The working time _T4 includes computing time and sleep time, wherein the computing time is when the receiving antenna 144 receives the second FM continuous wave signal, passes through the low noise amplifier 145, the mixer and the intermediate frequency amplifier 146, and the analog-to-digital converter 150 until The processing and operation of the processor 110 is completed, and the time for transmitting data via the communication and power supply unit 160 . The sleep time is from the trailing edge of the enabling time _T3 to the leading edge of the next enabling time _T3 , and the processor 110 issues a control command to suspend the amplification function of the power amplifier 130 to save power consumption.

Please refer to Fig. 8, which is a schematic front view showing an anti-trap detection device of an embodiment of the present case erected on a large bus. In this embodiment, the anti-pinch detection device 100 of the present case is mounted above the front door and the outer side of the middle door of the bus 200, but it is not limited thereto.

Please refer to Figure 9 and Figure 10 and cooperate with Figure 1, where Figure 9 shows a top view of the installation of a cylindrical body of an anti-pinch detection device according to an embodiment of the present case, and Figure 10 shows an implementation of this case A side view of erection of a cylindrical body of an anti-pinch detection device in an example. As shown in Figure 1, Figure 9 and Figure 10, the anti-pinch detection device 100 of this case further has a cylindrical body 180, in which at least a processor 110, a radio frequency generator 120, a power amplifier 130, and a radio frequency transceiver module 140 And the analog-to-digital converter 150 is disposed in the cylindrical body 180 . The radius of the cylindrical body 180 is preferably 3.5 cm, and the height of the cylindrical body is preferably 11 cm, but not limited thereto. The cylindrical body 180 is arranged above the outer side of the coach door 210 relative to the coach compartment 220. The coach door 210 can have different widths W according to different models, and the width W ranges from about 75 cm to 150 cm. 180 protrudes and is installed with the length L of one car body of bus door 210 to be 7 centimeters.

In some embodiments, at least the receiving antenna 144 and the transmitting antenna 143 are arranged above the outside of the bus door 210, and the receiving antenna 144 and the transmitting antenna 143 have the shortest detection distance and the farthest detection distance in the vertical direction towards the ground. distance. Preferably, the shortest detection distance is 0.3 to 0.7 meters, and the farthest detection distance is 1 to 2.2 meters, but not limited thereto.

In some embodiments, the origin of the coordinates after the anti-pinch detection device 100 is erected is the center position of the antenna surface of the anti-pinch detection device 100 . Selecting the first height H ₁ and the second height H ₂ makes the coverage of the antenna beam on the X-axis and the Y-axis approximate to different ellipses. For example: H ₁ =0.5m, the corresponding major axis and minor axis, (x1,y1)=(0.17m, 0.34m). H ₂ =2.2m, the corresponding major axis and minor axis, (x2,y2)=(0.76m, 1.5m). Covering three axes (X, Y and Z axes) approximately forms a flat cylinder, the first height H ₁ defines the shortest detection distance R _min , and the second height H ₂ defines the longest detection distance R _max . Due to different types of vehicles and different working environments, the first height H ₁ and the second height H ₂ should have different choices. In order to make the antenna coverage meet the requirements, the position must be adjusted in conjunction with the measurement after erection. When setting the processor parameters, the shortest detection distance and the furthest detection distance must also be adjusted.

Adjust the shortest detection distance, because the distance close to the anti-pinch detection device 100 corresponds to a very low frequency or even close to direct current, and for anti-pinch detection, the short distance close to the anti-pinch detection device 100, that is, the top of the car door, It has a lower priority than the longer distance, ie the bottom of the door. Therefore, the shortest detection distance should be defined; the furthest detection distance is close to the ground, such as: asphalt road or cement road, which has strong reflection, refraction or scattering to form stray waves, which will affect the signal-to-noise ratio. The IF processing circuit, that is, the mixer and the IF amplifier 146, has a Sensitivity Time Control (STC) function, so that the farther the distance is, the higher the frequency is, the greater the gain is.

In practice, small objects, such as the hem of a coat, a purse, or a part of an umbrella, have been caught in the past. Therefore, the anti-pinch detection device 100 of this case responds with a delay time, that is, when the anti-pinch detection device 100 detects an event that the target area is occupied, it starts an alarm, and when the event stops, it will be delayed for a period of time Then cancel the warning.

To sum up, the present invention provides an anti-pinch detection device for the door of a bus, by transmitting the first FM continuous wave signal, receiving the second FM continuous wave signal of the return trace, and performing signal and data processing to detect Detecting whether there are passengers or objects in the boarding and disembarking spaces inside and outside the doors of the bus can effectively ensure that accidents such as human body or objects will not be caught when the driver controls the door to close, thereby achieving the effect of truly improving safety.

Although the present invention has been disclosed with preferred embodiments, it is not intended to limit the present invention. Anyone skilled in this art can make various changes and modifications without departing from the spirit and scope of the present invention. Therefore, the present invention The scope of protection shall be determined by the scope of the attached patent application.

100: anti-pinch detection device 110: processor 1101: preprocessing unit 1102: fast Fourier transform unit 1103: clutter removal unit 1104: binary integral detection unit 1105: state output unit 120: radio frequency generator 130: power Amplifier 140: RF transceiver module 141: Coupler 142: Filter 143: Transmitting antenna 144: Receiving antenna 145: Low noise amplifier 146: Mixer and intermediate frequency amplifier 150: Analog-to-digital converter 160: Communication and power supply unit 170: driving console 180: cylindrical body 200: bus 210: bus door 220: bus compartment B: scanning bandwidth C: area FFT: fast Fourier transform f _b : difference frequency f _r : trace signal frequency f _t : frequency of transmitting signal H ₁ : first height H ₂ : second height L: length M: set the number of frames of the detected target pri_det: basic detection bit R _min : shortest detection distance R _max : The farthest detection distance sum: total value T: scan cycle T ₁ : time for the anti-pinch detection device to work once T ₂ : toilet preparation time T ₃ : enabling time T ₄ : working time T ₅ : continuous operation time T _C : Detection task cycle time Thres: Threshold value T _ref : Background detection time W: Width X: Axis Y: Axis Z: Axis

Figure 1: A block diagram of an anti-pinch detection device according to an embodiment of this case. Figure 2: The frequency-time correspondence diagram of the transmission signal, return signal and their phase difference of an anti-pinch detection device according to an embodiment of the present case. Figure 3: A schematic diagram of the antenna coverage of an anti-pinch detection device according to an embodiment of the present case. Figure 4: A block diagram of a processor of an anti-pinch detection device according to an embodiment of the present case. Fig. 5 (A) and Fig. 5 (B): An anti-trap detection device according to an embodiment of this case displays the relationship between the removal of clutter, the shortest detection distance and the furthest detection distance on the amplitude-frequency window correspondence graph schematic diagram. Figure 6: The workflow of the binary integral detection unit of an anti-pinch detection device according to an embodiment of this case. Fig. 7: A control timing diagram of an anti-pinch detection device according to an embodiment of the present case. Figure 8: A schematic diagram of the front view of an anti-pinch detection device of an embodiment of this case erected on a large bus. Figure 9: A top view of the erection of a cylindrical body of an anti-pinch detection device according to an embodiment of the present case. Figure 10: A side view of the installation of a cylindrical body of an anti-pinch detection device according to an embodiment of this case.

100: Anti-pinch detection device

110: Processor

120: RF generator

130: Power Amplifier

140: RF transceiver module

141: coupler

142: filter

143: Transmitting antenna

144: Receiving antenna

145: Low noise amplifier

146: Mixer and IF Amplifier

150:Analog to digital converter

160: Communication and power supply unit

170: Driving Console

Claims (10)

An anti-pinch detection device for a large passenger car door, comprising: a processor, providing a timing control signal and performing an anti-pinch detection; a radio frequency generator, electrically connected to the processor, for the The timing control signal generates a first FM continuous wave signal; a power amplifier is electrically connected to the radio frequency generator to amplify the first FM continuous wave signal; a radio frequency transceiver module is electrically connected to the power amplifier, Used to transmit the first FM continuous wave signal to a target area and receive a second FM continuous wave signal reflected by the target area, and generate a difference frequency between the first FM continuous wave signal and the second FM continuous wave signal signal; and an analog-to-digital converter, electrically connected with the radio frequency transceiver module and the processor, for converting the difference frequency signal into a data, and sending the data to the processor, so that the processor The anti-pinch detection is performed according to the data, and it is judged whether there are passengers or objects in the target area; wherein, the half-power beamwidth of the first FM continuous wave signal transmitted by the radio frequency transceiver module is 40 ^o × 20 ^o , and the The target area is a boarding and disembarking space covering the inside and outside of the bus door. The anti-pinch detection device as described in claim 1 further includes a communication and power supply unit, wherein the communication and power supply unit is electrically connected to the processor and provides an interface with a vehicle power supply, and when the anti-pinch detection When the judgment result of the test determines that there are passengers or objects in the target area, the communication and power supply unit transmits an anti-pinch message to a driving console. The anti-pinch detection device as described in Claim 1, wherein the radio frequency transceiver module includes a coupler, a filter, a transmitting antenna, a low noise amplifier, a receiving antenna, a mixer and an intermediate frequency amplifier , wherein the coupler distributes the first FM continuous wave signal amplified by the power amplifier to the filter, the mixer and the intermediate frequency amplifier, and the transmitting antenna distributes the first FM continuous wave signal filtered by the filter The wave signal is transmitted to the target area, the receiving antenna receives the second FM continuous wave signal reflected by the target area, the low noise amplifier amplifies the second FM continuous wave signal with low noise, and the mixer and intermediate The frequency amplifier mixes and filters the first FM continuous wave signal and the second FM continuous wave signal, and generates the difference frequency signal. The anti-pinch detection device as claimed in claim 3, wherein the coupler is electrically connected to the power amplifier, the transmitting antenna is electrically connected to the filter, and the receiving antenna is electrically connected to the low noise amplifier, and The mixer and the intermediate frequency amplifier are electrically connected with the low noise amplifier and the analog-to-digital converter. The anti-pinch detection device as described in claim 3, wherein at least the receiving antenna and the transmitting antenna are arranged above the outer side of the bus door, and the receiving antenna and the transmitting antenna have a vertical direction towards the ground. A minimum detection distance and a maximum detection distance. The anti-trap detection device according to claim 5, wherein the shortest detection distance is 0.3 to 0.7 meters, and the farthest detection distance is 1 to 2.2 meters. The anti-pinch detection device according to claim 1, wherein the processor includes a preprocessing unit, a fast Fourier transform unit, a clutter removal unit, a binary integral detection unit, and a state output unit, the The preprocessing unit processes the data and corrects outliers in the data. The fast Fourier transform unit receives the processed data, executes the Hamming window function, and performs fast Fourier transform to obtain a one-dimensional spectrum. The clutter removal unit extracts a background spectrum of the target area, and then subtracts the background spectrum from the one-dimensional spectrum to obtain a sampled spectrum and provides it to the binary integral detection unit, and the binary integral detection unit A binary integral detection is performed on the sampling frequency spectrum to obtain a detection state, and the state output unit outputs according to the detection state. The anti-pinch detection device as described in claim 7, wherein the binary integral detection is a detection of M out of N, N is the number of set frames, and M is the frame of the target object obtained by setting the detection Number of. The anti-pinch detection device as described in claim 8, wherein when a total value of the binary integral detection is 0, the detection state is a first state, and the state output unit outputs a signal of logic 0 ; When the binary integral detection starts counting, the total value is greater than 0 and less than M, the detection state is a second state, and the state output unit outputs a clock wave of logic 0 and 1 alternately; and when When the total value of the binary integral detection is greater than or equal to M, the detection state is a third state, and the state output unit outputs a logic 1 signal. The anti-pinch detection device as described in claim 1 further includes a cylindrical body, wherein the processor, the radio frequency generator, the power amplifier, the radio frequency transceiver module and the analog-to-digital converter are arranged on the cylinder In the shape body, the radius of the cylindrical body is 3.5 cm, the height of the cylindrical body is 11 cm, the cylindrical body system is arranged on the outer side of the bus door, and the cylindrical body is protrudingly installed with the bus The length of a car body of the car door is 7 centimeters.

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