CN102278960B - Non-contact measuring method for non-contant vehicle loading length - Google Patents

Abstract

A novel non-contact method for measuring the loading length of a vehicle relates to a non-contact method for measuring the loading length of the vehicle without stopping. The object of the present invention is to solve the problem of measuring the loading length that is difficult or costly due to the large difference in the loading of vehicles and the loading length measurement under the condition of vehicles queuing. The present invention utilizes the infrared light curtain sensor and the photoelectric switch to form a composite reference to judge whether there is a vehicle passing through, and uses software to first obtain the signal that the vehicle reaches the composite reference, and at this time, the single-chip microcomputer enters the preparatory measurement state. When the vehicle passes through the composite benchmark completely, start the ultrasonic ranging sensor, measure the distance l between the front of the vehicle and the ultrasonic ranging sensor, the distance between the ultrasonic ranging sensor and the composite benchmark is S, and use the software to calculate the loading length L of the vehicle =S-l. The invention adopts a double-reference trigger mechanism, which can solve the problem of measuring the loading length in the vehicle queuing situation.

Description

A new non-contact vehicle loading length measurement method

technical field

The invention relates to a non-contact method for measuring the loading length of a vehicle without stopping the vehicle.

Background technique

The extra length of the vehicle will affect the driving safety of the vehicle, especially when driving on a curve, the impact is more obvious. And some vehicles may not be too long, but the size of the vehicle is too long after loading the goods because the size of the goods is too large, and the materials and shapes of the goods loaded on the vehicles are different, which makes measurement very difficult. The patent publication number is CN1719190A, and the publication date is January 11, 2006. In the patent document, a kind of non-contact detection system for vehicle size is disclosed, and the length of the vehicle is calculated by a camera. A utility model patent document with the authorized notification number CN201133809Y discloses a method for measuring the length of a vehicle by using an infrared light curtain sensor. The former measurement method is complicated, the cost is high, and parking inspection is required. The latter requires a lot of photoelectric switches when measuring the length of the vehicle, and because the vehicle loads are high or low, it is impossible to measure the vehicle loading length when the vehicle loads are of different heights.

Contents of the invention

The purpose of the present invention is to solve the problem of measuring the loading length of the vehicle at the entrance of the expressway or before the vehicle enters the curve, so as to improve the driving safety of the vehicle. The vehicle loading length measuring method of the present invention is composed of a software control system, an infrared light curtain sensor, an ultrasonic distance measuring sensor, a photoelectric switch, a host computer interface and a single-chip microcomputer. The measuring method of the vehicle loading length of the present invention is realized through the following steps (Fig. 1, Fig. 2, Fig. 3): one, two pairs of infrared light curtain sensors 1 and 7 and their supports 2 and 8 are fixed; two, photoelectric switch 5 and 9 and its brackets 6 and 10 are fixed; three, the ultrasonic distance measuring sensor 3 is fixed with the corresponding support 4; four, the hardware facilities and software are communicated to obtain the information of the sensor; five, the vehicle is measured by the ultrasonic distance measuring sensor 3 The distance l between the front of the vehicle and the ultrasonic distance measuring sensor completely passes through the composite reference formed by the infrared light curtain sensor and the photoelectric switch; 5. The known distances between the ultrasonic ranging sensor and the two composite references are S1 and S2 respectively. For a vehicle with a longer loading length, the composite reference 1 is used as the trigger reference, and the software is used to calculate its loading length L=S1-l; for a vehicle with a shorter loading length, the composite reference 2 is used as the trigger reference, and the software is used to calculate its loading length L= S2-l. The working principle is: a pair of infrared light curtain sensor and photoelectric switch constitute a composite reference, only when the infrared light curtain sensor and photoelectric switch are triggered at the same time, it is considered that there is a vehicle passing by, avoiding misjudgment caused by man-made or external interference. When the vehicle passes the composite reference 1 formed by the infrared light curtain sensor 1 and the photoelectric switch 5, the single-chip microcomputer is triggered to enter the pre-measurement state, and when the vehicle passes the composite reference 1 completely, it does not reach the infrared light curtain sensor 7 and the photoelectric switch 9 When the composite benchmark 2 is formed, it is judged to be a shorter car. At this time, the composite benchmark 2 is used as the measurement benchmark. When the car passes the composite benchmark 2 completely, the single-chip microcomputer enters the measurement state, and the single-chip microcomputer starts the ultrasonic distance measuring sensor to measure the front of the car. The distance from the ultrasonic distance sensor. When the vehicle does not completely pass the composite benchmark 1, but the head of the vehicle has reached the composite benchmark 2, it is judged to be a longer vehicle, and the composite benchmark 1 is used as the measurement benchmark. When the composite reference 1 is completely passed, the microcontroller activates the ultrasonic ranging sensor to measure the distance between the front of the vehicle and the ultrasonic ranging sensor. The purpose of adopting this dual reference design is to solve the problem of queuing vehicles. The method of the invention has the advantages of simple structure of the required device, low cost, and is not limited by conditions such as material, geometric shape, weather, and external lighting of goods loaded on the vehicle.

Description of drawings

Figure 1 is a top view of the vehicle loading length measurement system, Figure 2 is a hardware diagram of the vehicle loading length measurement system, and Figure 3 is a schematic diagram of the vehicle passing through the measurement system.

Detailed ways

Specific embodiment one: (referring to Fig. 1,2,3) the vehicle loading length measuring system of the present embodiment is by software control system, two pairs of infrared light curtain sensors 1 and 7 and support 2 and 8, two pairs of photoelectric switches 5 and 9 And support 6 and 10, ultrasonic ranging sensor 3 and corresponding support 4, single-chip microcomputer composition.

Specific embodiment two: the measurement of the vehicle loading length of the present embodiment is realized through the following steps: one, two pairs of infrared light curtain sensors 1 and 7 and their supports 2 and 8 are fixed; two, photoelectric switches 5 and 9 and their supports 6 and 10 are fixed; three, the ultrasonic distance measuring sensor 3 is fixed with the corresponding support 4; four, the hardware facility is communicated with the software to obtain the information of the sensor; five, the ultrasonic distance measuring sensor 3 is used to measure that the vehicle passes through the infrared light completely The distance l between the front of the vehicle and the ultrasonic ranging sensor is the composite reference formed by the curtain sensor and the photoelectric switch; five, the known distances between the ultrasonic ranging sensor and the two composite references are S1 and S2 respectively. For a vehicle with a longer loading length, the composite reference 1 is used as the trigger reference, and the software is used to calculate its loading length L=S1-l; for a vehicle with a shorter loading length, the composite reference 2 is used as the trigger reference, and the software is used to calculate its loading length L= S2-l.

Specific embodiment three: When measuring the loading length of passing vehicles, a dual-reference trigger system is adopted. When a vehicle with a shorter loading length passes through the system, that is, the same vehicle cannot trigger the infrared light curtain sensor 1 and the photoelectric switch at the same time. The composite reference 1 composed of 5 and the composite reference 2 composed of the infrared light curtain sensor 7 and the photoelectric switch 9, at this time, the composite reference 2 composed of the infrared light curtain sensor 7 and the photoelectric switch 9 is used as the trigger reference for triggering the operation of the ultrasonic distance measuring sensor 3 , the distance between the ultrasonic ranging sensor 3 and the composite reference 2 is S2, then the vehicle loading length is L=S2-l at this time; when a vehicle with a longer loading length passes through the system, the same vehicle can trigger the composite reference 1 at the same time And composite reference 2, adopt composite reference 1 to be the trigger reference that triggers ultrasonic ranging sensor 3 work now, set the distance of ultrasonic ranging sensor 3 apart from composite reference 1 as S1, then the vehicle loading length is now L=S1-1 .

Embodiment 4: When installing two composite benchmarks and ultrasonic distance measuring sensors 3, it is required that 8m≤S2≤15m, 15m≤S1≤30m, and S1-S2≥8m.

Claims (4)

1. The method for non-contact measurement vehicle loading length under the situation of vehicle not stopping, is characterized in that: the measurement of vehicle loading length realizes by following steps: one, two pairs of infrared light curtain sensors (1,7) and first The support (2,8) is fixed; two, two pairs of photoelectric switches (5,9) are fixed with the second support (6,10); three, the ultrasonic ranging sensor (3) is carried out with the third support (4) Fixed; four, hardware facility and software are communicated, obtain the information of sensor; Five, utilize ultrasonic ranging sensor (3) to measure that vehicle passes through the composite reference 1 or the first photoelectric switch that the first infrared light curtain sensor and the first photoelectric switch constitute completely Two infrared light curtain sensors and the second photoelectric switch composite benchmark 2 o'clock the distance l between the front of the vehicle and the ultrasonic distance sensor; The dual reference trigger mechanism, when the vehicle passes the composite reference 1 composed of the first infrared light curtain sensor (1) and the first photoelectric switch (5), triggers the single chip microcomputer to enter the pre-measurement state, when the vehicle passes the composite reference 1 completely without When arriving at the composite reference 2 that the second infrared light curtain sensor (7) and the second photoelectric switch (9) constitute, judge it as a shorter car, at this moment take the composite reference 2 as the measurement reference, when this car passes through the composite reference completely At 2 o'clock, the single-chip microcomputer enters the measurement state, and the single-chip microcomputer starts the ultrasonic distance measuring sensor (3), measures the distance between the vehicle front and the ultrasonic distance measuring sensor, utilizes software to calculate its loading length L=S2-l, when the vehicle does not pass through the composite Benchmark 1, and when the front of the car has arrived at the composite benchmark 2, it is judged to be a longer car, and the composite benchmark 1 is used as the measurement benchmark. When passing through the composite benchmark 1 completely, the single-chip microcomputer starts the ultrasonic range sensor (3) to measure the front of the vehicle The distance between the ultrasonic ranging sensor and the software is used to calculate its loading length L=S1-l. 2. The method for non-contact measurement of vehicle loading length according to claim 1, characterized in that: the measuring device required for the method comprises two pairs of infrared light curtain sensors and corresponding supports, two pairs of Photoelectric switches and corresponding brackets, ultrasonic distance measuring sensors and corresponding brackets, single-chip microcomputers, and software control systems. 3. The non-contact method for measuring the loading length of a vehicle without stopping the vehicle according to claim 1, characterized in that: the infrared light curtain sensor and the photoelectric switch constitute a composite reference, the distance of which is 30-50cm, and only the infrared When the light curtain sensor and the photoelectric switch are triggered simultaneously, it is considered that there is a vehicle passing by. 4. The method for non-contact measurement of vehicle loading length without stopping the vehicle according to claim 1, characterized in that: when installing two composite benchmarks and ultrasonic distance measuring sensors (3), it is required that 8m≤S2≤ 15m, 15m≤S1≤30m, S1-S2≥8m.

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