WO2020259044A1

WO2020259044A1 - Monitoring system and monitoring method for measuring gross vehicle weight in real time

Info

Publication number: WO2020259044A1
Application number: PCT/CN2020/086620
Authority: WO
Inventors: 麦德荣; 谢振翔; 杨方剑; 范向晨; 王广乐; 毛帆; 钱佳玄; 韩创; 吕楠君
Original assignee: 麦德荣
Priority date: 2019-06-26
Filing date: 2020-04-24
Publication date: 2020-12-30
Also published as: CN110361082B; CN110361082A

Abstract

A monitoring system and monitoring method for measuring gross vehicle weight in real time, wherein the monitoring system comprises: a tire pressure monitoring system (TPMS) (5), used for measuring the internal air pressure of each tire of a vehicle; a tire and road surface contact length measuring system, used for measuring curvature data and distance data of each tire of the vehicle in contact with the road surface; a gross vehicle weight calculating system, used for calculating a gross vehicle weight by using the pressure data measured by the TPMS (5) and the curvature data and distance data measured by the tire and road surface contact length measuring system; and a monitoring system for real-time alarming, used for sending load bearing data, axle load data, the gross vehicle weight, basic vehicle information, and GPS positioning data to the driver and a corresponding supervision department in real time, in order to remind the driver to avoid overload and overrun. The supervision department determines whether the vehicle is currently overloaded or overrun on the basis of the data sent. The damage to roadbeds and road surfaces due to overload is reduced, and the maintenance costs of roads and bridges are reduced.

Description

Monitoring system and monitoring method for real-time measurement of total vehicle weight

This application claims the priority of a Chinese patent application filed with the Chinese Patent Office on June 26, 2019, the application number is 201910558687.3, and the invention title is "a monitoring system and monitoring method for real-time measurement of the total weight of a vehicle", all of which are approved The reference is incorporated in this application.

Technical field

The invention relates to the technical field of Internet of Vehicles, in particular to a monitoring system and a monitoring method for real-time measurement of total vehicle weight.

Background technique

In recent years, with the development of the market economy, the highway transportation industry has also developed rapidly, and the number and cargo capacity of various freight vehicles have increased year by year. From 2008 to 2017, the proportion of road freight volume increased from 74.1% to 78%. What comes with it is that the phenomenon of vehicle overload and overrun is very common. When the market's operating capacity cannot meet the transportation needs, car owners often encounter overload and overrun phenomena in pursuit of economic benefits, which in turn brings a series of problems. Data show that when the overload rate is 10%, the road damage rate will increase by 46% and the service life will be shortened by 32%. Vehicle overload will cause serious damage to the subgrade and pavement structure, causing road deflection and rutting, causing cracks or even collapse of the road. , Leading to a decline in the service life of roads, an increase in road maintenance costs, and also cause environmental pollution, traffic safety hazards, and disrupt the order of the transportation market.

Therefore, the weight monitoring of freight vehicles is very important. At this stage, mostly static weighing and dynamic weighing methods are adopted, and the equipment is mainly installed at highway toll gates or main entrances and exits of highways. Static weighing is the use of a platform scale and its improved portable weighing instrument. The platform's working principle is to measure the total weight of the vehicle. The weighed object or the loaded vehicle is placed on the carrier table, and under the action of gravity, it passes through the carrier. The gravity is transmitted to the load cell, the elastic body of the load cell is deformed, and the strain gauge bridge attached to the elastic body loses balance, and outputs an electrical signal proportional to the weight value. The signal is amplified by a linear amplifier, and then The A/D is converted into digital signals, and the weight signals are processed by the CPU of the instrument and the weight data is displayed directly. This method can only perform random inspections, which is time-consuming and inefficient, and the installation and operation of the portable weighing instrument is more troublesome. Dynamic weighing is mainly based on axle load detection, allowing the vehicle to pass through the axle weighing platform at a certain speed to achieve the purpose of dynamic weighing. However, the time for vehicle tires to pass through the platform is very short due to some interference factors such as tire driving force, vibration load, etc. Therefore, the force acting on the weighing platform is not the actual weight of the vehicle, the measurement accuracy is low, and it is difficult to implement overload control in remote areas where underground weighing equipment cannot be installed.

At present, the control of overload and overload generally adopts the weighing toll system based on dynamic weighing. Most of these traditional weighing methods require the establishment of large-scale inspection stations on the main road of the highway. There are the following shortcomings: weighing fixed inspection equipment is very restricted by the station. Real-time detection and determination of illegal and over-limit transportation vehicles. The detected vehicles are relatively concentrated, the measurement accuracy error is large, the detection efficiency is low, and it is easy to cause traffic jams, and the vehicles are also easy to bypass the inspection and so on. With the development of the transportation industry, traditional weighing methods can no longer meet current needs. Therefore, a more efficient and convenient way to monitor the total vehicle weight in real time is needed.

Summary of the invention

Based on this, the purpose of the present invention is to provide a monitoring system and monitoring method for real-time measurement of the total weight of a vehicle, so as to accurately measure the current total mass data of the vehicle in real time.

To achieve the above objective, the present invention provides a monitoring system for real-time measurement of the total weight of a vehicle, the monitoring system includes:

The tire pressure monitoring system TPMS is used to measure the internal air pressure of each tire of the vehicle;

A measurement system for the contact length between tires and the road surface, used to measure the curvature data and distance data of each tire of the vehicle in contact with the road surface;

The calculation system for the total vehicle weight is respectively connected with the TPMS and the measurement system for the contact length of the tire and the road, and is used for the pressure data measured by the TPMS and the curvature data measured by the measurement system for the contact length of the tire and the road Calculate the total vehicle weight with distance data;

Real-time alarm monitoring system, connected with the calculation system of the total weight of the vehicle, used to send load-bearing data, axle load data, total weight of the vehicle, basic vehicle information and GPS positioning data to the vehicle driver and corresponding supervision in real time To remind vehicle drivers to avoid overloading and over-limit, the supervisory authority judges whether the vehicle is currently overloaded or over-limit based on the data sent.

Optionally, the TPMS includes: multiple pressure measurement sensors and multiple wireless transmission devices; the number of pressure measurement sensors and the number of wireless transmission devices are the same as the number of vehicle tires; the pressure measurement sensor and the The wireless transmission device is integrated and installed inside the wheel; the pressure measurement sensor is connected to the calculation system of the total vehicle weight through the wireless transmission device.

Optionally, the system for measuring the contact length between the tire and the road surface includes:

Multiple curvature sensors, multiple laser ranging sensors, and multiple wireless transmission devices; the number of curvature sensors and the number of laser ranging sensors are the same as the number of tires, and the number of wireless transmission devices is equal to the curvature The sum of the number of sensors and the number of the laser ranging sensor; the curvature sensor and the wireless transmission device are integrated and installed inside the wheel, and the laser ranging sensor and the wireless transmission device are integrated and installed inside the wheel The curvature sensor and the laser ranging sensor are respectively connected to the calculation system of the total vehicle weight through the wireless transmission device.

Optionally, the curvature sensor is arranged on the inner wall of the tire carcass along the center line of the inner side of the tire; the laser ranging sensor is installed on the rim to correspond to the position of the inner side of the tire, and the laser emitting point of the laser ranging sensor is located at On the plane where the center line of the inner side of the tire is located, as the wheel rotates, the laser distance measuring sensor always measures the distance from the same point on the center line of the inner side of the tire to the laser distance measuring sensor.

The present invention also provides a monitoring method for real-time measurement of the total weight of a vehicle. The method is applied to the above monitoring system, and the method includes:

Step S1: The calculation system of the total vehicle weight obtains the internal air pressure of each tire of the vehicle measured by TPMS; the calculation system of the total vehicle weight obtains the curvature of the contact length between the tires and the road surface measured by the measurement system of each tire of the vehicle and the road surface Data and distance data;

Step S2: The calculation system of the total vehicle weight calculates the contact length between the tire and the road surface according to the curvature data and the distance data;

Step S3: The calculation system of the total vehicle weight calculates the contact area of each tire of the vehicle with the ground according to the tire tread width and the contact length between the tire and the road surface;

Step S4: The calculation system of the total vehicle weight calculates the load-bearing data of each tire of the vehicle according to the contact area between the tire and the ground and the internal air pressure of the tire;

Step S5: The calculation system of the total vehicle weight adds the bearing data of all tires at both ends of the axle to obtain the axle load data of a single axle;

Step S6: The calculation system of the total vehicle weight adds the axle load data of all the axles of the vehicle to obtain the total vehicle weight.

Optionally, calculate the contact length between the tire and the road as follows:

When the vehicle speed is 0, the length of the contact between the tire and the road is L = lα, where l is the total length of the curvature sensor from a curve to a straight line, and α is the correction coefficient of the crown thickness.

When the vehicle speed is lower than the set value, the contact length between the tire and the road is L = lα, where l is the total length of the tire inner side center line from a curve to a straight line, and α is the correction coefficient of the crown thickness.

When the vehicle speed is higher than the set value, the length of the contact between the tire and the road surface is L = lα, where l is the total length of the straight part of the tire inner center line, and α is the correction coefficient of the crown thickness.

Optionally, the specific formula for calculating the contact area between each tire of the vehicle and the ground is:

S=wL, where S is the contact area of each tire of the vehicle with the ground, w is the tread width, and L is the length of the tire in contact with the road.

Optionally, the specific formula for calculating the load-bearing data of each tire of the vehicle is:

G=PS, where G is the load-bearing data of each tire of the vehicle, P is the measured air pressure inside the tire, and S is the calculated contact area of each tire of the vehicle with the ground.

According to the specific embodiments provided by the present invention, the present invention discloses the following technical effects:

(1) The curvature sensor used in the present invention is arranged on the inner wall of the tire carcass along the center line of the inner side of the tire, and the laser distance measuring sensor is installed on the rim, corresponding to the position of the inner side of the tire, and there is no need to build a station for laying.

(2) The present invention uses the air pressure inside the tire and the contact area between the tire and the road surface to accurately calculate the bearing data of each tire of the vehicle, the axle load data of each axle, and the total weight of the vehicle volume, and accurately reflect whether the vehicle currently exists Overloading and over-limit violations.

(3) The present invention uses wireless transmission technology and GPS positioning technology to achieve all-weather, anytime, anywhere non-stop, non-queuing measurement, and real-time transmission of vehicle model information, total vehicle weight, GPS positioning and other information to the supervision department, effectively monitoring overload and overload Restrictions and illegal acts of cheating are conducive to relevant departments to increase supervision, reduce overload damage to subgrades and pavements, reduce maintenance costs of roads and bridges, and extend the service life of roads and bridges.

Description and drawings

In order to explain the embodiments of the present invention or the technical solutions in the prior art more clearly, the following will briefly introduce the drawings needed in the embodiments. Obviously, the drawings in the following description are only some of the present invention. Embodiments, for those of ordinary skill in the art, without creative labor, other drawings can be obtained from these drawings.

Figure 1 is a schematic diagram of the position of the outer centerline of wheels and tires used in 9 types of vehicles in the national standard;

Figure 2 is a plan view of the wheel cut along a plane that bisects the center line of the tire outside;

Figure 3 is a perspective view of the wheel cut along a plane that bisects the center line of the tire outside;

Figure 4 is a plan view obtained by cutting the wheel along the plane where the centerline of the outer side of the tire is located;

Figure 5 is a plan view of the wheel bearing deformation obtained by cutting the wheel along the plane where the centerline of the outer side of the tire is located;

Figure 6 shows the single wheel axle (one tire on one side) used in category 9 vehicles;

Figure 7 shows the dual wheel axles (two tires on one side) used in Type 9 vehicles;

Figure 8 is a schematic diagram of the distance-related time curve obtained by the laser ranging sensor as the wheel rotates;

Figure 9 is a schematic diagram of the distance-dependent length curve obtained by the laser ranging sensor as the wheel rotates;

Figure 10 is a schematic diagram of a nine-category vehicle;

Fig. 11 is a working flow chart of the monitoring system for real-time measurement of total vehicle weight of the present invention.

In the figure, 1. The center line of the outer side of the tire; 2. The curvature sensor; 3. The laser distance measuring sensor; 4. The launch path; 5. TPMS; 6. The rim; 7. The center line of the inner side of the tire; 8. Single tire; 9. Axle ; 10. Double tires; 11. Double wheel axles.

Detailed ways

The technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative work shall fall within the protection scope of the present invention.

The purpose of the present invention is to provide a monitoring system and a monitoring method for real-time measurement of the total vehicle weight, so as to accurately measure the current total quality data of the vehicle in real time.

In order to make the above-mentioned objects, features and advantages of the present invention more obvious and easy to understand, the present invention will be further described in detail below in conjunction with the accompanying drawings and specific embodiments.

The present invention is described by taking 9 types of vehicles in the national standard, that is, six-axle trucks as an example; the present invention discloses a monitoring system for real-time measurement of total vehicle weight. The monitoring system includes a tire pressure monitoring system TPMS5, and measurement of tire-road contact length System, vehicle gross weight calculation system and real-time alarm monitoring system.

The TPMS5 is used to measure the internal air pressure of each tire of the vehicle, and send the internal air pressure to the calculation system of the total vehicle weight in real time; the measurement system of the contact length between the tires and the road is used to determine the contact of each tire of the vehicle with the road And send the measured curvature data and distance data to the total vehicle weight calculation system in real time; the total vehicle weight calculation system first uses the curvature data and distance data to calculate the contact of each tire with the road surface Length, and then use the contact length and tire width data to calculate the contact area of each tire with the road surface, and then use the contact area of each tire and the road surface and the internal air pressure of each tire to calculate the load-bearing data of each tire, and then the axle 9 The load-bearing data of all tires at both ends are added to obtain the axle load data of a single axle. Finally, all the axle load data of the vehicle are added to obtain the total vehicle weight, and the load-bearing data, axle load data, and total vehicle weight are sent to the real-time alarm Monitoring system; the real-time alarm monitoring system is used to send load-bearing data, axle load data, total vehicle weight, basic vehicle information, and GPS positioning data to the vehicle driver and corresponding regulatory authorities in real time to remind the vehicle driver to avoid Overload and overrun, the regulatory authority can judge whether the vehicle is currently overloaded or overrun based on the above data.

As shown in Figure 2, the TPMS5 is installed on the side of the wheel rim 6. It includes the same number of pressure measurement sensors and wireless transmission devices as the number of vehicle tires. As shown in Figures 6, 7, and 10, 9 types of vehicles include a total of 5 There are two dual-type wheel axles 11 and one single-type wheel axle, so a total of 22 pressure measuring sensors for measuring tire pressure and 22 wireless transmission devices are required, and the internal air pressure of each tire is transmitted to each of the wireless transmission devices in real time. The calculation system of the total vehicle weight, the pressure measuring sensor and the wireless transmission device are integrated and installed on the rim 6.

The measurement system for the contact length of tires and road surfaces includes the same number of curvature sensors 2 and laser ranging sensors 3 as the tires, and a wireless transmission device integrated with them, which transmits the collected curvature data and distance data to the total weight of the vehicle in real time. In the calculation system, the curvature sensor 2 and the wireless transmission device are integrated and installed inside the wheel, and the laser ranging sensor 3 and the wireless transmission device are integrated and installed inside the wheel; as shown in Figure 2, Figure 3, Figure 4, and Figure 5, the curvature sensor 2 is a closed ring sensor, which is arranged on the inner wall of the tire carcass along the inner center line 7 of the tire; as shown in Figure 2, Figure 3, Figure 4, the laser ranging sensor 3 is installed on the rim 6 corresponding to the position on the inner side of the tire , And the laser emitting point of the laser ranging sensor 3 is located on the plane where the tire inner centerline 7 is located. As the wheel rotates, the laser ranging sensor 3 always measures the same point on the tire inner centerline 7 to the laser ranging sensor 3, the emission path 4 of the laser ranging sensor 3 is shown in Figure 2, Figure 3, and Figure 4. As shown in Figure 6, Figure 7, Figure 10, 9 types of vehicles include a total of 5 dual-type wheel axles 11 and a single-type wheel axle, so a total of 22 laser ranging sensors 3 are required; the flat length of the inner tire is the center of the inner tire The total length of the line 7 from a curve to a straight line; the contact length between the tire and the road is the total length of the centerline 1 of the tire outside from a curve to a straight line, as shown in Figure 1.

The total vehicle weight calculation system includes a microcomputer, a wireless transmission device and a database of basic vehicle information. The microcomputer uses the curvature data and distance data received in real time to first calculate the flat length of the tire inner center line 7, as shown in Figure 5. Calculate the contact length between the tire and the road surface, and then calculate the contact area between the tire and the road surface, and then calculate the load-bearing data of each tire of the vehicle, the axle load data of each axle, and the total weight of the vehicle by integrating the internal air pressure of the tire, and then calculate the total weight of each tire The load-bearing data of each axle, the axle load data of each axle and the total vehicle weight are sent to the real-time alarm monitoring system; the basic vehicle information database includes vehicle type, curb weight, approved load quality, total vehicle weight, axle group type, number of tires, Data such as tire size, rim 6 size, wheel size, 7 circumference of tire inner center line and tread width.

The real-time alarm monitoring system displays the vehicle's axle load data, total vehicle weight, GPS positioning data to the vehicle driver and the corresponding supervisory department. The system judges the vehicle based on the vehicle type, axle load data, total vehicle weight data and GPS positioning data Whether the current overload and limit exceeded.

As shown in Figure 11, the present invention also provides a method for monitoring the total weight of a vehicle, the method including:

Step S1: Obtain pressure, curvature data and distance data: the calculation system of the total vehicle weight obtains the internal air pressure of each tire of the vehicle measured by TPMS5; the calculation system of the total vehicle weight obtains the measurement system of the contact length between the tire and the road The curvature data and distance data of each tire of the vehicle in contact with the road surface.

Step S2: Determine the contact length between the tire and the road surface: The calculation system of the total vehicle weight calculates the contact length between the tire and the road surface based on the curvature data and the distance data.

Specifically, when the vehicle speed is 0, the crown of the tire contacting the road surface is squeezed, which will cause the shape of the portion of the annular curvature sensor 2 close to the road surface to change, and then the curvature of the annular curvature sensor 2 will change, according to the annular curvature. The curvature change of the curvature sensor 2 is used to determine the deformation length l of the curvature sensor 2. Since the tire crown has a certain thickness, the length of the contact part between the tire and the road surface should be multiplied by a correction coefficient α, then the length of the tire contact with the road surface L=lα, because the tire crown width, pattern, etc. are not the same, the tires of different specifications choose the corresponding α.

When the vehicle speed is lower than the set value, as shown in Figure 8, with the rotation of the wheels, the laser ranging sensor 3 can collect a sufficient number of continuous data points to reflect the distance of the measured point. The laser ranging sensor The change of the distance of 3 with time is the time-distance (TD) curve. The lowest point of the curve indicates that the measured point is at the lowest point in the vertical direction. After ΔT, the curve reaches the lowest point again. The inside of the tire is known The centerline has a 7-perimeter ΔL, and the speed at this point can be calculated as V=ΔL/ΔT. Using L=VT, the time-distance (TD) curve shown in Figure 8 can be converted into the length shown in Figure 9. -Distance (LD) curve, the length-distance (LD) curve has periodicity. In one period, it is first a straight line A composed of a series of points with a distance value of D ₂ and then a series of continuous distance values. curve B D consisting of ₂ points, the difference between the abscissa of the curve B is the start and end points of the inner side of the tire center line 7 by curve becomes a straight line length l of the total, since the crown has a certain thickness, so that a partial length of the tire contact with the road Should be multiplied by a correction coefficient α, then the length of the contact between the tire and the road is L = lα. Because the tire crown width and pattern are not the same, the corresponding α is used for tires of different specifications.

When the vehicle speed is higher than the set value, as shown in Figure 5, with the rotation of the wheels, if the laser ranging sensor 3 cannot collect a sufficient number of continuous data points to reflect the distance of the measured point The change of the distance of the laser ranging sensor 3 with time, that is, time-distance (TD). When the distance is the smallest, the measured point is located at the lowest point in the vertical direction. The distance is D ₁ , and the length is the maximum. D ₂ , the radius D ₃ of the rim 6 is known, and the distance between the launch point of the laser ranging sensor 3 and the bottom end of the laser ranging sensor 3 is D ₄ (that is, the thickness of the laser ranging sensor 3 itself), by the right triangle Pythagorean theorem

It can be seen that when the distance measured by the laser sensor is D ₁ , the line between the measured point and the laser emission point perpendicularly bisects the straight part of the tire inner center line 7, so the total length of the straight part of the tire inner center line 7 Length l = 2D _x . Because the tire crown has a certain thickness, the length of the contact part between the tire and the road surface should be multiplied by a correction coefficient α. Then the length of the tire contact with the road surface is L = lα. All the same, use the corresponding α for tires of different specifications.

The choice of three different measurement methods based on the vehicle speed is in order to obtain as accurate results as possible under theoretical conditions. In actual use, the three different measurement methods can be arbitrarily combined and sequenced according to different environments.

Step S3: Calculate the contact area between the tire and the road: The calculation system of the total vehicle weight uses the tire tread width and the measured contact length between the tire and the road to calculate the contact area S between each tire of the vehicle and the ground. The specific method is as follows: S=wL, where w is the tread width, which is the known information in the basic vehicle information database, and L is the length of the tire in contact with the road surface.

Step S4: Calculate the weight of the tire: The calculation system of the total vehicle weight can calculate the weight of each tire of the vehicle by using the data of the contact area between the tire and the ground and the data of the air pressure inside the tire. The specific method is as follows: 1) The tire has been determined in step The internal air pressure is P, that is, the pressure P of the contact part between the tire and the road surface. Step 3) has determined that the contact area between the tire and the road surface is S, and the load bearing of the tire is G=PS.

Step S5: Calculate the axle load of a single axle 9: The calculation system of the total vehicle weight adds the bearing data of all tires at both ends of the axle 9 to obtain the axle load data of a single axle. The specific method is: for a single axle (8 ), the axle load is the sum of the loads of the two tires on both sides; for a single axle (10 double tires on each side), the axle load is the sum of the loads of the four tires on both sides.

Step S6: Calculate the total weight of the vehicle: The calculation system of the total weight of the vehicle adds the axle weight data of all the axles 9 of the vehicle to obtain the total weight of the vehicle.

Step S7: Determine whether the vehicle is overloaded or overrun: the monitoring system of real-time warning judges whether the vehicle is currently overloaded or overrun according to the vehicle type, axle load data, total vehicle weight and GPS positioning data.

There are many types of curvature sensors 2 suitable for the present invention, including strain gauge sensors, optical fiber curvature sensors, and flexible curvature sensors. The following experiment uses strain gauge curvature sensors and low-power laser distance sensors to compare the two groups Experiments have proved the feasibility and accuracy of the present invention for real-time measurement of the total vehicle weight and monitoring of whether the vehicle is currently overloaded or over-limit violations.

experiment one

A static weighing comparison experiment was carried out at the Moon Bay Comprehensive Depot in Nanshan District, Shenzhen, Guangdong Province: The method of measuring the total vehicle weight of the present invention was compared with the traditional weighing method of a platform scale. The total number of samples was 2 9 types of vehicles. For the two 9-category vehicles in the sample, the motor vehicle driving license issued by the vehicle management shows that the total vehicle weight of the two vehicles is 47280kg, the curb weight is 7780kg, and the approved load weight is 39500kg. Use the same type of wheels for the corresponding positions. Since the main purpose of the present invention is to monitor whether the vehicle is overloaded and overrun, according to the algorithm of curb weight plus the total mass of goods, after the goods are overloaded, the total vehicle weight of the two sample vehicles is about 60,000 kg. Sequentially, strain gauge curvature sensors, low-power laser ranging sensors, and TPMS systems are installed on the 44 wheels of two 9-category vehicles. The monitoring system for real-time measurement of the total vehicle weight of the present invention counts each 9 In order to ensure the objective and effective data of the total vehicle weight of this type of vehicle, when the vehicle is parked on the loadometer, the vehicle speed is zero and the tires have cooled, after about 50s, the loadometer and the present invention measure the total vehicle weight at the same time.

Specific data and comparison results are shown in Table 1 and Table 2:

Table 1 Comparison of the static measurement of the No. 1 vehicle of the present invention and the data measured by the weighbridge

Table 2 Comparison of the static measurement of the present invention and the data measured by the weighbridge

It can be seen from the above table that the total weight of the known sample vehicle is about 60,000kg, the actual total weight of the sample 1 vehicle measured by the present invention is 60009.824kg, and the total vehicle weight measured by the traditional weighing platform is 59994kg. Compared with the traditional platform, The error of the present invention is 15.824 kg.

It can be seen from the above table that the total weight of the known sample vehicle is about 60,000kg, the actual total weight of the sample 2 vehicle measured by the present invention is 60001.96kg, and the total vehicle weight measured by the traditional weighing platform is 59996kg. Compared with the traditional weighing platform, The error of the present invention is 5.959 kg.

Compared with the traditional weighing platform, the overall error rate of the present invention is (15.824+5.959)/(2×6000)=1.8×10-4, which shows that the present invention can accurately measure the total vehicle weight when the vehicle speed is 0. And the accuracy is 0.001kg, compared with the traditional weighing method of platform scale, it also has the characteristics of small error.

Experiment two

A dynamic weighing comparison experiment was carried out on Yueliangwan Avenue, Nanshan District, Shenzhen, Guangdong Province: The total weight of the vehicle measured by the present invention was compared with the weighing result of the platform scale in Experiment 1. The total number of samples was 2 vehicles of 9 categories , After inspection, for the two 9-category vehicles in the sample, the motor vehicle license issued by the vehicle management shows that the total vehicle weight of the two vehicles is 47280kg, the curb weight is 7780kg, and the approved load weight is 39500kg. 9 types of cars use the same type of wheels in the corresponding positions. Since the main purpose of the present invention is to monitor whether the vehicle is overloaded or overrun, according to the algorithm of curb weight plus the total mass of goods, after the goods are overloaded, the total vehicle weight of the two sample vehicles is about 60,000 kg. In turn, curvature sensors, laser ranging sensors, and TPMS systems are installed on the 44 wheels of two 9-category vehicles. To ensure the objective and effective data, when the vehicle speed is stable, the present invention randomly collects data on the total weight of the vehicle .

Specific data and comparison results are shown in Table 3:

Table 3 Comparison of the data measured by the dynamic weighing of the present invention and the floor scale

It can be seen from Table 3 that for the sample vehicle 1, the present invention collects data for the total weight of the vehicle 6 times at different vehicle speeds. Compared with the weighing scale, when the vehicle speed is 68.95km/h, the difference is The absolute value is the largest, and the maximum value is 15.109. When the vehicle speed is 5.3km/h, the absolute value of the difference is the smallest, and the minimum value is 3.365. On the whole, the average error rate of the measurement under 6 different vehicle speeds 0.00015185.

For sample vehicle 2, the present invention collects data for the total weight of the vehicle 6 times at different vehicle speeds. Compared with the weighing of a floor scale, when the vehicle speed is 55.69km/h, the absolute value of the difference is the largest, the largest The value is 15.325. When the vehicle speed is 3.57km/h, the absolute value of the difference is the smallest, and the minimum value is 3.985. On the whole, the average error rate of the measurement under 6 different vehicle speeds is 0.00014122.

According to the present invention, the total vehicle weight data measured by the two sample vehicles at different speeds are consistent on the overall level, and the total average error rate is 0.000147, indicating that the present invention measures the total vehicle weight during the driving process. Accurate.

In addition, the advantage of the present invention is that the data collection scheme used is not limited by time and space. Regardless of the location of the vehicle, the axle load, total vehicle weight, speed, GPS positioning and other information can be transmitted to the regulatory authorities and The driver judges whether the vehicle is currently overloaded or over-limit violations by integrating the current axle limit and weight limit on the road where the vehicle is located.

The various embodiments in this specification are described in a progressive manner. Each embodiment focuses on the differences from other embodiments, and the same or similar parts between the various embodiments can be referred to each other.

Specific examples are used in this article to illustrate the principles and implementation of the present invention. The description of the above examples is only used to help understand the method and core idea of the present invention; at the same time, for those of ordinary skill in the art, according to the present invention There will be changes in the specific implementation and scope of application. In summary, the content of this specification should not be construed as limiting the present invention.

Claims

A monitoring system for real-time measurement of total vehicle weight, characterized in that the monitoring system includes:

The tire pressure monitoring system TPMS is used to measure the internal air pressure of each tire of the vehicle;

A measurement system for the contact length between tires and the road surface, used to measure the curvature data and distance data of each tire of the vehicle in contact with the road surface;

The calculation system for the total vehicle weight is respectively connected with the TPMS and the measurement system for the contact length of the tire and the road, and is used for the pressure data measured by the TPMS and the curvature data measured by the measurement system for the contact length of the tire and the road Calculate the total vehicle weight with distance data;

Real-time alarm monitoring system, connected with the calculation system of the total weight of the vehicle, used to send load-bearing data, axle load data, total weight of the vehicle, basic vehicle information and GPS positioning data to the vehicle driver and corresponding supervision in real time To remind vehicle drivers to avoid overloading and over-limit, the supervisory authority judges whether the vehicle is currently overloaded or over-limit based on the data sent.
The monitoring system for real-time measurement of total vehicle weight according to claim 1, wherein the TPMS comprises: a plurality of pressure measurement sensors and a plurality of wireless transmission devices; the number of the pressure measurement sensors and the wireless transmission device The number of is the same as the number of vehicle tires; the pressure measurement sensor and the wireless transmission device are integrated and installed inside the wheel; the pressure measurement sensor is connected to the calculation system of the total vehicle weight through the wireless transmission device.
The monitoring system for measuring the total vehicle weight in real time according to claim 1, wherein the measuring system for the contact length between the tire and the road surface comprises:

Multiple curvature sensors, multiple laser ranging sensors, and multiple wireless transmission devices; the number of curvature sensors and the number of laser ranging sensors are the same as the number of tires, and the number of wireless transmission devices is equal to the curvature The sum of the number of sensors and the number of the laser ranging sensor; the curvature sensor and the wireless transmission device are integrated and installed inside the wheel, and the laser ranging sensor and the wireless transmission device are integrated and installed inside the wheel The curvature sensor and the laser ranging sensor are respectively connected to the calculation system of the total vehicle weight through the wireless transmission device.
The monitoring system for real-time measurement of total vehicle weight according to claim 3, characterized in that the curvature sensor is arranged on the inner wall of the tire carcass along the inner center line of the tire; the laser ranging sensor is installed on the rim corresponding to the tire The inner position is set, and the laser emitting point of the laser ranging sensor is located on the plane where the center line of the inner side of the tire is located. With the rotation of the wheel, the laser ranging sensor always measures the same point on the center line of the inner side of the tire. Describe the distance of the laser ranging sensor.
A monitoring method for real-time measurement of the total weight of a vehicle, the method being applied to the monitoring system according to any one of claims 1 to 4, wherein the method comprises:

Step S1: The calculation system of the total vehicle weight obtains the internal air pressure of each tire of the vehicle measured by TPMS; the calculation system of the total vehicle weight obtains the curvature of the contact length between the tires and the road surface measured by the measurement system of each tire of the vehicle and the road surface Data and distance data;

Step S2: The calculation system of the total vehicle weight calculates the contact length between the tire and the road surface according to the curvature data and the distance data;

Step S3: The calculation system of the total vehicle weight calculates the contact area of each tire of the vehicle with the ground according to the tire tread width and the contact length between the tire and the road surface;

Step S4: The calculation system of the total vehicle weight calculates the load-bearing data of each tire of the vehicle according to the contact area between the tire and the ground and the internal air pressure of the tire;

Step S5: The calculation system of the total vehicle weight adds the bearing data of all tires at both ends of the axle to obtain the axle load data of a single axle;

Step S6: The calculation system of the total vehicle weight adds the axle load data of all the axles of the vehicle to obtain the total vehicle weight.
The monitoring method for real-time measurement of total vehicle weight according to claim 5, wherein the calculation of the contact length between the tire and the road surface is as follows:

When the vehicle speed is 0, the length of contact between the tire and the road surface is L=lα, where l is the total length of the curvature sensor from a curve to a straight line, and α is the correction coefficient of the crown thickness.
The monitoring method for real-time measurement of total vehicle weight according to claim 5, wherein the calculation of the contact length between the tire and the road surface is as follows:

When the vehicle speed is lower than the set value, the length of the tire contacting the road surface is L = lα, where l is the total length of the tire inner center line from a curve to a straight line, and α is the correction coefficient of the crown thickness.
The monitoring method for real-time measurement of total vehicle weight according to claim 5, wherein the calculation of the contact length between the tire and the road surface is as follows:

When the vehicle speed is higher than the set value, the length of the contact between the tire and the road surface is L = lα, where l is the total length of the straight part of the tire inner center line, and α is the correction coefficient of the crown thickness.
The monitoring method for real-time measurement of the total vehicle weight according to claim 5, wherein the specific formula for calculating the contact area of each tire of the vehicle with the ground is:

S=wL, where S is the contact area of each tire of the vehicle with the ground, w is the tread width, and L is the length of the tire in contact with the road.
The monitoring method for real-time measurement of the total weight of the vehicle according to claim 5, wherein the specific formula for calculating the weight bearing data of each tire of the vehicle is:

G=PS, where G is the load-bearing data of each tire of the vehicle, P is the measured air pressure inside the tire, and S is the calculated contact area of each tire of the vehicle with the ground.