A by-wire semi-trailer tank commercial vehicle scaled test device

Abstract

The utility model discloses a kind of line control semi-trailer liquid tank commercial vehicle scale-down test device, including with actual semi-trailer liquid tank vehicle scale-down mapping scale-down test car body, the scale-down test car body includes tractor and liquid tank trailer connected by hinged mechanism, the liquid tank trailer top is equipped with liquid tank, the liquid tank top is equipped with water inlet and bottom is equipped with drain, the liquid tank trailer top is uniformly provided with multiple acquisition mechanics data's module, the scale-down test device includes control device, multiple acquisition mechanics data's module is respectively connected with control device signal end. The utility model can be low cost, high reliability verify semi-trailer liquid tank vehicle braking performance and steering stability strategy development and verification under different load conditions, can be widely applied in vehicle testing operation field.

Description

Technical Field

[0001] This utility model relates to the field of vehicle testing operations, and in particular to a scaled-down test device for a wire-controlled semi-trailer liquid tank commercial vehicle. Background Technology

[0002] With the increasing demand for bulk liquid transportation, semi-trailer commercial liquid tank trucks often operate under complex conditions, making vehicle safety and stability paramount. Liquid within the tank is prone to violent sloshing during vehicle acceleration, deceleration, or turning, causing a continuous shift in the vehicle's center of gravity and potentially leading to serious accidents such as spillage or rollover. Therefore, it is necessary to simulate load variations under various mixed operating conditions during the vehicle design phase to test the stability of commercial semi-trailer liquid tank trucks and optimize vehicle stability control strategies. However, traditional testing methods often rely on real-vehicle trials or bench tests, which are costly, difficult to set up, and unsuitable for supporting multi-scenario parameter iteration and performance evaluation. Furthermore, existing testing platforms often struggle to simulate the dynamic center of gravity changes caused by tank sloshing.

[0003] Currently, commercial vehicle testing platforms primarily employ a testing mode that relies on simulation and hardware-in-the-loop testing, supplemented by vehicle testing. This approach suffers from insufficient data digitization, hindering the accurate creation of simulation models and falling short of meeting the ever-increasing testing demands for system functionality and performance in the context of wired control. Traditional platforms rely heavily on wired connections for data acquisition and control, lacking real-time interaction capabilities with simulation platforms, which is detrimental to closed-loop control strategy testing and digital twin research. Utility Model Content

[0004] The purpose of this invention is to overcome the shortcomings of the aforementioned background technology and provide a wire-controlled semi-trailer liquid tank commercial vehicle scaled-down test device. This device accurately maps the structure and dynamic parameters of the semi-trailer liquid tank vehicle to the scaled-down test vehicle body, realizes braking test parameter mapping, and has the ability to calculate the dynamic center of gravity. It solves the problem that existing test platforms cannot simulate and measure the dynamic changes of the liquid center of gravity of liquid tank vehicles. It can verify the braking performance and steering stability strategies of semi-trailer liquid tank vehicles under different load conditions in a low-cost and highly reliable manner.

[0005] This utility model provides a wire-controlled semi-trailer liquid tank commercial vehicle scaled-down test device, including a scaled-down test vehicle body that is scaled down to an actual semi-trailer liquid tank vehicle. The scaled-down test vehicle body includes a tractor and a liquid tank trailer connected by an articulated mechanism. The liquid tank trailer has a liquid tank on its top, with a water inlet on the top and a drain outlet at the bottom. Multiple modules for collecting mechanical data are evenly distributed on the top of the liquid tank trailer. The scaled-down test device includes a controller, and the multiple modules for collecting mechanical data are respectively connected to the signal terminal of the controller.

[0006] In the above technical solution, the control device includes a vehicle driving state simulation system and a rapid prototyping control system connected via a CAN (Controller Area Network) bus. The tractor is equipped with a twin vehicle ECU (electronic control unit). Each module that collects pressure data is connected to the twin vehicle ECU. The twin vehicle ECU is connected to the vehicle driving state simulation system via a data communication module. The rapid prototyping control system is connected to the twin vehicle ECU via a data communication module.

[0007] In the above technical solution, the module for collecting mechanical data is a pressure sensor that dynamically identifies and calculates the position of the center of mass in real time. There are three pressure sensors, which are arranged in an equilateral triangle on the top of the liquid tank trailer. The data communication module is an MQTT (Message Queuing Telemetry Transport) wireless communication module. Each pressure sensor is connected to the twin vehicle ECU, and the twin vehicle ECU is connected to the vehicle driving state simulation system through the MQTT wireless communication module.

[0008] The above technical solution also includes a drive module for controlling the driving speed and attitude of the tractor and the tank trailer. The drive module includes two servo controllers, multiple hub motors located on both sides of the tractor and the tank trailer, and a battery located in the tractor. The output terminal of the battery is connected to the power input terminals of the two servo controllers and the hub motors, respectively. The signal terminals of the two servo controllers are connected to the control terminals of the twin vehicle ECU, and the control terminals of the two servo controllers are connected to the signal terminals of each hub motor.

[0009] In the above technical solution, the drive module further includes a steer-by-wire device, and the front of the tractor is provided with an Ackerman steering mechanism. The signal terminal of the steer-by-wire device is connected to the control terminals of two servo controllers, and the control terminals of the steer-by-wire device are respectively connected to the signal terminals of the Ackerman steering mechanism.

[0010] In the above technical solution, the controller also includes a cloud server for storing and transmitting data. The rapid prototyping control system is connected to the cloud server via a CAN bus, and the MQTT wireless communication module is connected to the cloud server.

[0011] In the above technical solution, the tractor is equipped with a first vehicle positioning module and a first IMU (Inertial Measurement Unit) sensor, and the tank trailer is equipped with a second vehicle positioning module and a second IMU sensor. The first vehicle positioning module, the second vehicle positioning module, the first IMU sensor, and the second IMU sensor are all connected to the signal terminal of the twin vehicle ECU.

[0012] In the above technical solution, the liquid tank trailer is equipped with a vehicle speed sensor connected to the ECU signal terminal of the twin vehicle.

[0013] The above technical solution also includes a commercial vehicle drive-by-wire Hil test bench that is connected to a cloud server via a CAN bus.

[0014] In the above technical solution, the twin vehicle ECU, pressure sensor, MQTT wireless communication module, two-way servo controller, hub motor, battery, steer-by-wire system, steering mechanism, first vehicle positioning module, second vehicle positioning module, first IMU sensor, second IMU sensor, and vehicle speed sensor are connected via a CAN bus; the MQTT wireless communication module is located on the tractor; the liquid tank is provided with multiple coaxially arranged annular baffles, and corresponding holes connecting the various spaces of the liquid tank are provided at the corresponding positions of adjacent annular baffles; the steer-by-wire semi-trailer liquid tank commercial vehicle scale-down test device also includes a target test vehicle that achieves parameter mapping with the scale-down test vehicle body via a CAN bus.

[0015] This utility model of a wire-controlled semi-trailer liquid tank commercial vehicle scaled-down test device has the following beneficial effects:

[0016] (1) Low experimental cost and high testing efficiency: The relevant dynamic data generated during the operation of the twin vehicle is converted into corresponding real vehicle parameters through the principle of similarity. The vehicle mapped by the twin test vehicle can be flexibly changed according to different test requirements, and then the data is transmitted to simulation platforms such as IPG TruckMaker through a cloud server. Compared with directly building a vehicle simulation model for simulation experiments, the data obtained by the twin vehicle is more accurate and closer to the real vehicle; compared with directly using the real vehicle for experiments, the twin vehicle has low test cost, low setup difficulty, high test efficiency and wide scene coverage.

[0017] (2) Fast dynamic response: The use of distributed hub motor drive eliminates the need for complex transmission mechanisms, resulting in a significantly faster dynamic response speed for the twin test vehicle compared to traditional experimental equipment. Furthermore, the hub motors facilitate integration with various intelligent control systems, further enhancing the vehicle's intelligence level. This provides a solid foundation for the rapid verification and iteration of future new technologies.

[0018] (3) Accurate simulation of dynamic center of mass characteristics: An adjustable liquid tank load module is installed in the middle of the twin vehicle. The module is made of transparent acrylic material, which reproduces the center of mass shift and swaying torque caused by liquid sloshing during acceleration, braking and turning of the actual semi-trailer liquid tank truck, and provides more accurate test data. Through the dynamic center of mass tracking mechanism, the offset law of the liquid load center of mass of the liquid tank under typical working conditions such as vehicle turning and emergency braking can be accurately captured, providing key experimental data support for inertial modeling, path offset compensation and control strategy design in complex working conditions.

[0019] (4) Strong real-time data interactivity and flexible equipment layout: The twin vehicle adopts a dual-channel communication architecture based on CAN bus and MQTT protocol. CAN bus has strong real-time performance, long transmission distance, strong anti-electromagnetic interference capability, and low cost. All modular components in the vehicle exchange data in real time through CAN bus, and the exchange delay can be as low as milliseconds. MQTT protocol is highly efficient and energy-saving, with reliable data transmission and support for bidirectional communication. Through MQTT protocol, the twin vehicle transmits data to the simulation platform, and at the same time, the simulation platform issues vehicle control commands in real time. The two perform remote real-time data exchange, so that the layout of the simulation platform is not affected by the twin vehicle. Attached Figure Description

[0020] Figure 1 This is a schematic diagram of the structure of the scaled-down test vehicle body in the wire-controlled semi-trailer liquid tank commercial vehicle scaled-down test device of this utility model;

[0021] Figure 2 This is a schematic diagram of the control hardware system architecture in the scaled-down test device for a semi-trailer liquid tank commercial vehicle of this utility model. Detailed Implementation

[0022] The present invention will be further described in detail below with reference to the accompanying drawings and embodiments, but these embodiments should not be construed as limiting the present invention.

[0023] Existing commercial vehicle testing methods suffer from limitations in the accuracy of simulation testing and the difficulty in coupling multiple execution systems for joint testing in hardware-in-the-loop testing, resulting in low system flexibility.

[0024] Against this backdrop, this invention proposes a drive-by-wire semi-trailer liquid tank commercial vehicle scaled-down test device. Not only do its vehicle parameters correspond to the target vehicle, but it also integrates an adjustable liquid tank load module in the middle of the scaled-down test vehicle's body. By flexibly calculating the mass distribution and center of gravity position through changes in the injection volume and liquid density, it ensures that the inertial characteristics of the scaled-down test vehicle during acceleration, braking, and steering are highly consistent with the actual vehicle. Simultaneously, the system, based on a dual-channel communication architecture using CAN bus and MQTT protocol, enables millisecond-level data interaction between the scaled-down test vehicle and simulation platforms such as IPG TruckMaker, effectively supporting online iteration and performance evaluation of commercial vehicle driving stability control algorithms.

[0025] See Figures 1 to 2 This utility model discloses a wire-controlled semi-trailer liquid tank commercial vehicle scaled-down test device, comprising a scaled-down test vehicle body that is scaled down to an actual semi-trailer liquid tank vehicle. The scaled-down test vehicle body includes a tractor 1 and a liquid tank trailer 2 connected by a hinge mechanism 3. The liquid tank trailer 2 has a liquid tank 12 on its top, with a water inlet 13 on its top and a drain outlet 14 on its bottom. In this embodiment, the liquid tank 12 has multiple coaxially arranged annular baffles 15, and adjacent annular baffles 15 have corresponding through holes connecting the various spaces of the liquid tank 12. The liquid tank trailer 2 has multiple modules for collecting mechanical data evenly distributed on its top. The scaled-down test device includes a controller, and the multiple modules for collecting mechanical data are respectively connected to the signal terminals of the controller.

[0026] The controller includes a vehicle driving state simulation system and a rapid prototyping control system connected via a CAN bus. The tractor 1 is equipped with a twin vehicle ECU 11. Each module that collects pressure data is connected to the twin vehicle ECU 11. The twin vehicle ECU 11 is connected to the vehicle driving state simulation system via a data communication module. The rapid prototyping control system is connected to the twin vehicle ECU 11 via a data communication module.

[0027] The module for collecting mechanical data is a pressure sensor 16 that dynamically identifies and calculates the position of the center of mass in real time. There are three pressure sensors 16 arranged in an equilateral triangle on the top of the liquid tank trailer 2. The data communication module is an MQTT wireless communication module 10. In this embodiment, the MQTT wireless communication module 10 is located on the tractor 1. Each pressure sensor 16 is connected to a twin vehicle ECU 11, and the twin vehicle ECU 11 is connected to the vehicle driving state simulation system through the MQTT wireless communication module 10.

[0028] This utility model of a wire-controlled semi-trailer liquid tank commercial vehicle scaled-down test device also includes a drive module for controlling the driving speed and attitude of the tractor 1 and the liquid tank trailer 2. The drive module includes two servo controllers 7, multiple hub motors 8 located on both sides of the tractor 1 and the liquid tank trailer 2, and a battery 9 located inside the tractor 1. The output terminals of the battery 9 are connected to the power input terminals of the two servo controllers 7 and the hub motors 8, respectively. The signal terminals of the two servo controllers 7 are connected to the control terminals of the twin vehicle ECU 11, and the control terminals of the two servo controllers 7 are connected to the signal terminals of each hub motor 8.

[0029] The drive module also includes a steer-by-wire device. The front of the tractor 1 is equipped with an Ackerman steering mechanism 4. The signal terminal of the steer-by-wire device is connected to the control terminal of two servo controllers 7. The control terminal of the steer-by-wire device is connected to the signal terminal of the Ackerman steering mechanism 4.

[0030] The controller also includes a cloud server for storing and transmitting data. The rapid prototyping control system is connected to the cloud server via a CAN bus, and the MQTT wireless communication module is also connected to the cloud server.

[0031] The tractor 1 is equipped with a first vehicle positioning module 5 (1) and a first IMU sensor 6 (1), and the tank trailer 2 is equipped with a second vehicle positioning module 5 (2) and a second IMU sensor 6 (2). The first vehicle positioning module 5 (1), the second vehicle positioning module 5 (2), the first IMU sensor 6 (1) and the second IMU sensor 6 (2) are all connected to the signal terminal of the twin vehicle ECU 11. The tank trailer 2 is equipped with a vehicle speed sensor 17 connected to the signal terminal of the twin vehicle ECU 11. In this embodiment, the twin vehicle ECU 11, pressure sensor 16, MQTT wireless communication module 10, two-way servo controller 7, hub motor 8, battery 9, steer-by-wire, steering mechanism 4, first vehicle positioning module 5 (1), second vehicle positioning module 5 (2), first IMU sensor 6 (1), second IMU sensor 6 (2) and vehicle speed sensor 17 are connected via a CAN bus.

[0032] This utility model's wire-controlled semi-trailer liquid tank commercial vehicle scaled-down test device also includes a commercial vehicle wire-controlled Hil test bench connected to a cloud server via a CAN bus. The device also includes a target test vehicle that achieves parameter mapping with the scaled-down test vehicle body via a CAN bus.

[0033] As attached Figure 1The diagram shows the hardware layout of the scaled-down test vehicle. The purpose of this scaled-down test vehicle is to conduct in-depth research on the dynamic behavior and stability control strategies of semi-trailer tank trucks under complex working conditions with low cost and high safety. This requires scaled-down mapping and experimental design based on the structural layout, dynamic configuration, and load characteristics of actual semi-trailer tank trucks. The scaled-down test vehicle body is constructed to simulate the actual structure of a typical semi-trailer tank truck at a 1:4 scale, consisting of a tractor unit 1 and a tank trailer 2 connected by a flexible articulation mechanism 3. The tractor unit 1 has an Ackermann steering mechanism 4 driven by a steer-by-wire system installed at its front. To ensure that the dynamic characteristics of the scaled-down test vehicle body are highly consistent with the actual vehicle, key structural parameters are equivalently mapped according to the similarity principle and Buckingham's π theorem. The entire scaled-down test vehicle body adopts a three-axle, six-wheel layout, with each axle driven by two independently and symmetrically arranged hub motors 8, and equipped with a two-way servo controller 7 for differential control of the hub motors 8 on each axle. During actual testing of semi-trailer tank trucks, including acceleration, deceleration, and steering, the liquid in the tank experiences significant sloshing, altering the center of gravity of both the tank and the trailer. Therefore, an acrylic transparent liquid tank 12 is installed on the upper part of the tank trailer 2 in the scaled-down test vehicle. The tank 12 has an inlet 13 at the front for injecting liquid and a drain 14 at the rear for draining liquid, facilitating adjustment of the filling ratio and real-time monitoring of the internal liquid dynamics. An annular baffle 15 is designed inside the tank 12 to separate the filling space. Three pressure sensors 16 are installed on the top of the tank trailer 2, positioned at different locations in a stable triangular distribution. To achieve dynamic identification of the liquid load distribution and real-time calculation of the center of gravity, a real-time inversion model of the liquid's two-dimensional center of gravity position is constructed based on the principle of static torque balance. Given the coordinates of the installation positions of the three pressure sensors 16 and the corresponding measured vertical pressures, and considering that the sensing areas of each pressure sensor 16 are approximately the same or known, the corresponding vertical support forces can be calculated separately. These three points form a support triangle, creating a stable support system. When the liquid inside the tank 12 is in a static or quasi-steady-state motion, its mass can be considered to be equivalently concentrated at a certain two-dimensional coordinate point. The resultant torque at any reference point should be equal to the sum of the resultant torques of the three support forces about that point. Therefore, the position of the center of mass in the plane can be solved by satisfying the corresponding torque balance condition. In actual experiments, due to the significant inertia of the liquid, the liquid surface will tilt or sway to varying degrees, causing the liquid center of mass to dynamically shift in the vehicle's direction of travel. To achieve dynamic tracking of the liquid center of mass during braking, a time dimension is introduced into the original static center of mass calculation model, and a real-time sampling-based instantaneous torque balance method is used to continuously estimate the dynamic center of mass position.Three pressure sensors 16, positioned on the top of the liquid tank trailer 2, continuously collect pressure change data of their sensed areas at a fixed sampling frequency. This data is then converted into vertical support force values ​​at each moment. A two-dimensional centroid coordinate calculation model of the liquid load is constructed in real time at the current point in time. The real-time coordinates of the centroid are calculated by combining the geometric positions of the pressure sensors 16 in the coordinate system of the top surface of the liquid tank trailer 2. This method does not require complex modeling of the internal shape distribution of the liquid; it only relies on the load data and coordinate information of the three pressure measurement points at the bottom to accurately calculate the current position of the liquid centroid. It has advantages such as clear calculation logic, strong real-time performance, and low implementation cost. By embedding this calculation algorithm, continuous estimation of the liquid tank load state can be achieved, supporting dynamic tracking of the centroid under different liquid level heights and liquid disturbance conditions. This provides key technical support for the reconstruction of the mass distribution of the scaled-down test vehicle body during braking and steering tests. To improve the adaptability of the scaled-down test vehicle body to other types of commercial vehicles, the liquid tank 12 can be replaced with other types of load modules to study the impact of different loads on the stability control performance and path tracking accuracy of different commercial vehicles.

[0034] The braking control strategy for commercial vehicles requires logical judgment and command output based on the real-time dynamic state of the vehicle. Simultaneously, the impact of the stability control strategy also needs to be evaluated by acquiring the dynamic state of the vehicle after its actions. Therefore, it is necessary to accurately collect and analyze dynamic parameters such as speed, acceleration, and steering angle of the scaled-down twin vehicle during the test. Both the tractor 1 and the tank trailer 2 are equipped with a vehicle positioning module 5 and an IMU sensor 6. The vehicle positioning module 5 can accurately locate the position of the scaled-down test vehicle, and the IMU sensor 6 can acquire the longitudinal and lateral accelerations of the tractor 1 and the tank trailer 2. The scaled-down test vehicle's drive module consists of a one-to-two two-channel servo controller 7, a hub motor 8, a battery module 9, and a steer-by-wire system. The hub motor 8 can achieve precise traction and braking control by controlling the input current, adapting to the test requirements of complex conditions such as rapid braking and steering in dynamic testing. Therefore, the hub motor 8 is chosen to replace the traditional mechanical braking scheme. A vehicle speed sensor 17 is installed inside the tank trailer 2 to acquire the real-time speed of the scaled-down test vehicle.

[0035] Furthermore, at the system level, the testing process of the scaled-down test vehicle body needs to coordinate with other systems, including the vehicle driving state simulation system and the rapid prototyping control system. Real-time test parameters need to be synchronized between these systems; therefore, the scaled-down test vehicle body needs to have the ability to receive, process, and upload test parameters in real time. An MQTT wireless communication module 10, a twin vehicle ECU 11, and a scaled-down twin vehicle battery 9 are centrally installed in the tractor unit 1. The MQTT wireless communication module 10 is used to send the scaled-down test vehicle body test data collected by various sensors to a cloud server. The cloud server acts as a data hub, connecting the various test systems. The scaled-down test vehicle body communicates with the vehicle driving state simulation system and the commercial vehicle drive-by-wire Hil test bench through the cloud server. The twin vehicle ECU 11 is used to receive and integrate various sensor signals and control commands from the data acquisition module, converting them into control signals and sending them to two servo controllers 7 to control the motion state of the scaled-down test vehicle body. The drive-by-wire steering system receives the control signals from the twin vehicle ECU 11 and controls the steering mechanism 4 to achieve the steering function. Battery 9 is installed in tractor 1 to provide power to all hardware and ensure the normal operation of the scaled-down test vehicle's body system.

[0036] To achieve efficient collaborative control and data sharing between the scaled-down test vehicle and external test systems, a dual-channel data interaction system architecture integrating CAN bus and MQTT protocol was constructed. This architecture is based on the test vehicle's internal CAN network, enabling high-speed wired transmission of various sensor signals, control commands, and execution feedback. Simultaneously, low-latency bidirectional communication with the remote simulation platform and cloud server is achieved through the MQTT wireless communication module 10 deployed on the tractor unit 1. During the data interaction process, dynamic parameters (including the position, attitude, speed, acceleration, wheel torque, wheel speed, turning angle, and liquid centroid coordinates of the tractor and trailer) collected by various modules of the scaled-down test vehicle (such as IMU sensor 6, vehicle positioning module 5, vehicle speed sensor 17, steer-by-wire system, and pressure sensor 16) are centralized to the twin vehicle ECU 11 via the CAN bus. After data integration and preprocessing, the twin vehicle ECU 11 uploads key test data to the cloud server in real time via the MQTT protocol. As the system's data hub, the cloud server is responsible not only for centralized data storage and caching but also for issuing control commands from the vehicle driving state simulation system (IPGTruckMaker) and the rapid prototyping control system. After constructing the virtual test scenario and calculating the desired control parameters, the vehicle driving state simulation system forwards these parameters to the MQTT wireless communication module 10 via the cloud server. The ECU 11 of the digital twin vehicle then parses the parameters and drives the corresponding wheel hub motors 8 or steer-by-wire to execute the corresponding actions, thus achieving closed-loop control of the digital twin system. The system possesses high-concurrency communication capabilities and highly stable data consistency, enabling it to maintain real-time, accurate, and continuous data interaction under complex dynamic test conditions.

[0037] As attached Figure 2 The control hardware test system architecture of the scaled-down test vehicle shown comprises five parts: a vehicle driving state simulation system, a rapid prototyping control system, a cloud server, a commercial vehicle drive-by-wire HIL test bench, and the hardware mounted on the scaled-down test vehicle body. The vehicle driving state simulation system can set up a virtual vehicle test environment, including vehicle driving conditions, vehicle state parameters, and road scenarios. The vehicle driving state simulation system is connected to the rapid prototyping control system via a CAN bus. The rapid prototyping control system receives the parameters of the virtual vehicle test environment and outputs the target torque and target steering angle for each wheel hub. The cloud server, as a crucial node for data relay and storage in the entire system, receives the target torque and steering angle for each wheel calculated by the rapid prototyping control system and transmits this information to the scaled-down test vehicle body. The MQTT wireless communication module 10 in the scaled-down test vehicle body's data communication module receives the target torque and steering angle information, unifies the message, and transmits it to the twin vehicle ECU 11. The twin vehicle ECU 11 sends control commands to two servo controllers 7, which control the wheel hub motors 8 on each axle to perform corresponding actions. Meanwhile, the scaled-down twin vehicle's data acquisition module acquires real-time test parameters such as wheel speed, vehicle position, wheel torque, steering mechanism angle, test vehicle acceleration, and test vehicle speed from the scaled-down test vehicle. It then transmits these sensor signals to the twin vehicle's EC11U via the CAN bus. The twin vehicle's ECU11 processes the test parameters and sends them back to the cloud server via the MQTT wireless communication module 10. The cloud server then transmits the received information, including the actual torque, actual steering angle, vehicle speed, and yaw rate of each wheel of the scaled-down test vehicle, back to the rapid prototyping control system. The rapid prototyping control system then controls the commercial vehicle drive-by-wire HIL test bench to perform hardware actions for hardware-in-the-loop performance testing. The key technology of this test system architecture is that the dynamic parameters and braking and steering parameters of the scaled-down test vehicle are twinned with the vehicle dynamic parameters of the vehicle driving state simulation system and the braking parameters output by the commercial vehicle drive-by-wire HIL test bench, respectively. Furthermore, the rapid prototyping control system can achieve closed-loop feedback control based on the real test parameters acquired from the scaled-down test vehicle. Therefore, the experimental system architecture has a high degree of experimental confidence. Through this experimental mode, different stability control strategies and different hardware can be tested in a low-cost and high-safety manner, and relatively reliable results can be obtained.

[0038] Addressing the challenges of high cost, significant risk, and difficulty in early design verification during full-scale vehicle testing, scaled-down test vehicle technology can achieve low-speed dynamic similarity verification by proportionally reducing the size and weight of the entire vehicle, thereby significantly reducing experimental costs and improving testing efficiency. With the development of autonomous driving technology and intelligent connected vehicles, various vehicle execution systems are evolving towards intelligence and automation. Traditional braking and steering systems based on hydraulics and pneumatics are gradually evolving into advanced steer-by-wire systems. Steer-by-wire technology, through electronic signal transmission, achieves rapid mass transfer and precise execution, greatly improving control efficiency.

[0039] Obviously, those skilled in the art can make various modifications and variations to this utility model without departing from its spirit and scope. Therefore, if these modifications and variations fall within the scope of the claims of this utility model and their equivalents, this utility model also intends to include these modifications and variations.

[0040] The contents not described in detail in this specification are existing technologies known to those skilled in the art.

Claims

1. A scaled-down test device for a wire-controlled semi-trailer liquid tank commercial vehicle, characterized in that: The test vehicle body includes a scaled-down test vehicle body that is mapped to an actual semi-trailer tanker vehicle. The scaled-down test vehicle body includes a tractor (1) and a tanker trailer (2) connected by an articulation mechanism (3). The tanker trailer (2) has a tank (12) on its top. The tank (12) has a water inlet (13) on its top and a drain outlet (14) on its bottom. Multiple modules for collecting mechanical data are evenly distributed on the top of the tanker trailer (2). The scaled-down test device includes a controller. The multiple modules for collecting mechanical data are connected to the signal terminals of the controller. The controller includes a vehicle driving state simulation system and a rapid prototyping control system connected via a CAN bus. The tractor (1) is equipped with a twin vehicle ECU (11). Each module for collecting pressure data is connected to the twin vehicle ECU (11). The twin vehicle ECU (11) is connected to the vehicle driving state simulation system via a data communication module. The rapid prototyping control system is connected to the twin vehicle ECU (11) via a data communication module. The modules for collecting mechanical data are for dynamically identifying and calculating the center of mass position in real time. The pressure sensor (16) is arranged in an equilateral triangle on the top of the tank trailer (2). The data communication module is an MQTT wireless communication module (10). Each pressure sensor (16) is connected to the twin vehicle ECU (11). The twin vehicle ECU (11) is connected to the vehicle driving state simulation system through the MQTT wireless communication module (10). The system also includes a drive module for controlling the driving speed and attitude of the tractor (1) and the tank trailer (2). The drive module includes two servo controllers (7), multiple hub motors (8) located on both sides of the tractor (1) and the tank trailer (2), and a battery (9) located in the tractor (1). The output end of the battery (9) is connected to the power input end of the two servo controllers (7) and the hub motors (8). The signal end of the two servo controllers (7) is connected to the control end of the twin vehicle ECU (11). The control end of the two servo controllers (7) is connected to the signal end of each hub motor (8).

2. The wire-controlled semi-trailer liquid tank commercial vehicle scaled-down test device according to claim 1, characterized in that: The drive module also includes a steer-by-wire device. The front of the tractor (1) is provided with an Ackermann steering mechanism (4). The signal end of the steer-by-wire device is connected to the control end of two servo controllers (7). The control end of the steer-by-wire device is connected to the signal end of the Ackermann steering mechanism (4).

3. The wire-controlled semi-trailer liquid tank commercial vehicle scaled-down test device according to claim 2, characterized in that: The controller also includes a cloud server for storing and transmitting data. The rapid prototyping control system is connected to the cloud server via a CAN bus, and the MQTT wireless communication module is also connected to the cloud server.

4. The wire-controlled semi-trailer liquid tank commercial vehicle scaled-down test device according to claim 3, characterized in that: The tractor (1) is equipped with a first vehicle positioning module (5 (1)) and a first IMU sensor (6 (1)), and the tank trailer (2) is equipped with a second vehicle positioning module (5 (2)) and a second IMU sensor (6 (2)). The first vehicle positioning module (5 (1)), the second vehicle positioning module (5 (2)), the first IMU sensor (6 (1)) and the second IMU sensor (6 (2)) are all connected to the signal terminal of the twin vehicle ECU (11).

5. The wire-controlled semi-trailer liquid tank commercial vehicle scaled-down test device according to claim 4, characterized in that: The liquid tank trailer (2) is equipped with a vehicle speed sensor (17) connected to the signal terminal of the twin vehicle ECU (11).

6. The wire-controlled semi-trailer liquid tank commercial vehicle scaled-down test device according to claim 5, characterized in that: It also includes a commercial vehicle drive-by-wire HIL test bench that connects to a cloud server via a CAN bus.

7. The wire-controlled semi-trailer liquid tank commercial vehicle scaled-down test device according to claim 6, characterized in that: The twin vehicle ECU (11), pressure sensor (16), MQTT wireless communication module (10), two-way servo controller (7), hub motor (8), battery (9), steer-by-wire system, steering mechanism (4), first vehicle positioning module (5 (1)), second vehicle positioning module (5 (2)), first IMU sensor (6 (1)), second IMU sensor (6 (2)) and vehicle speed sensor (17) are connected via CAN bus; The MQTT wireless communication module (10) is located on the tractor (1); The liquid tank (12) is provided with multiple annular baffles (15) arranged coaxially, and the adjacent annular baffles (15) are respectively provided with through holes connecting each space of the liquid tank (12); The wire-controlled semi-trailer liquid tank commercial vehicle scaled-down test device also includes a target test vehicle that achieves parameter mapping with the scaled-down test vehicle body via a CAN bus.

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