CN112683264B

CN112683264B - Special vehicle liftoff detection system and detection method

Info

Publication number: CN112683264B
Application number: CN202011477947.3A
Authority: CN
Inventors: 王志福; 李昊龙; 梁常春; 王瑞
Original assignee: Beijing Institute of Technology BIT; Beijing Institute of Spacecraft System Engineering
Current assignee: Beijing Institute of Technology BIT; Beijing Institute of Spacecraft System Engineering
Priority date: 2020-12-15
Filing date: 2020-12-15
Publication date: 2023-02-28
Anticipated expiration: 2040-12-15
Also published as: CN112683264A

Abstract

A special vehicle liftoff detection system and a detection method are disclosed, wherein the system is composed of a hub motor, a motor controller, an Inertia Measurement Unit (IMU), a signal processing unit and a display; the system is characterized in that the hub motors transmit all motor torque step signals to the signal processing unit through the motor controller, the IMU transmits the horizontal acceleration of the vehicle to the signal processing unit, the signal processing unit judges whether the two signals simultaneously meet the vehicle ground-off condition or not, and determines whether ground-off warning is sent to a display screen to be displayed or not according to the judgment result. The invention can be realized through a simple system structure, has high detection sensitivity and accuracy, and can realize quick decision for vehicles with wheel layout forms of four wheels, six wheels, eight wheels and the like.

Description

Special vehicle liftoff detection system and detection method

Technical Field

The invention belongs to the technical field of whole vehicle design of special vehicles, and particularly relates to a liftoff detection technology suitable for special vehicles such as lunar vehicles and the like when the special vehicles work on unpaved road surfaces and in a low gravity environment.

Background

The manned lunar vehicle is used as the core component of the manned detection lunar surface activity system and bears the basic functions of rapid transfer of lunar surface astronauts, emergency rescue, efficient material transportation and the like. Plays an indispensable role in developing detection tasks, ensuring the safety of astronauts, improving the working efficiency and the like. Due to the low gravity and the soft soil on the surface of the moon, the surface of the moon is rugged and uneven, the road conditions such as stones, pits and slopes are complex, and the low gravity environmental characteristics of the moon are added, so that dangerous conditions such as wheel soaring, rollover and sideslip are very easy to occur in the process of rapid vehicle running. Therefore, the lunar vehicle has higher requirements and control on the operation stability than the common ground vehicle. However, there is no targeted solution to the above technical problems in the prior art.

Disclosure of Invention

In view of the above, in order to detect whether a special vehicle lifts off the ground or empties in real time and execute necessary vehicle stability control in a low gravity environment on a non-paved road surface, the invention provides a special vehicle lift-off detection system, which specifically comprises:

the system comprises a plurality of hub motors, a motor controller, an Inertia Measurement Unit (IMU) and a signal processing unit;

the motor controller is used for detecting the torques of the hub motors in real time and transmitting detected torque signals to the signal processing unit;

the inertial measurement unit is used for detecting the horizontal acceleration of the wheel in real time and transmitting a detected horizontal acceleration signal to the signal processing unit;

when the motor controller detects that the torque of the hub motor has a step signal, the signal processing unit judges whether the vehicle is lifted off the ground or not based on the step signal and the horizontal acceleration signal, and sends a torque control signal to the motor controller to perform torque adjustment on the hub motor.

Further, the step of judging whether the vehicle is lifted off the ground by the signal processing unit specifically includes: when the torque signals of part of the hub motors have positive-to-negative step signals, determining that the corresponding wheel lifts off the ground; and when the torque signals of all the hub motors simultaneously generate step signals from positive to negative, judging according to the horizontal acceleration, and if the horizontal acceleration is 0, determining that all the wheels are emptied and the vehicle is lifted off.

Furthermore, the special vehicle liftoff detection system is also provided with a display screen, and is suitable for the design of manned driving, and the signal processing unit sends out a warning signal through the display screen when the vehicle liftoff occurs, and prompts a driver to execute necessary operation.

Correspondingly, the invention also provides a method for detecting liftoff of the special vehicle by using the system, which specifically comprises the following steps:

the torque of the hub motors is detected in real time, and detected torque signals are transmitted to the signal processing unit;

detecting the horizontal acceleration of the wheel in real time, and transmitting a detected horizontal acceleration signal to the signal processing unit;

and the signal processing unit judges whether the vehicle is lifted off the ground or not based on the step signal and the horizontal acceleration signal when the motor controller detects that the torque of the in-wheel motor has the step signal, and sends a torque control signal to adjust the torque of the in-wheel motor.

Further, the process of determining whether the vehicle is off the ground specifically includes: when the torque signals of part of the hub motors have positive-to-negative step signals, determining that the corresponding wheel lifts off the ground; when the torque signals of all the hub motors simultaneously have step signals from positive to negative, judging according to the horizontal acceleration, and if the horizontal acceleration is 0, determining that all the wheels are emptied and the vehicle is lifted off the ground.

Further, for a person driving a special vehicle, the signal processing unit sends out a display signal for warning the driver when the vehicle leaves the ground, and prompts the driver to execute necessary operations.

According to the method and the system provided by the invention, whether special vehicles such as a lunar vehicle empty or not is judged by detecting whether the hub motors of all wheels simultaneously generate negative torque step signals and signals that the horizontal acceleration of the vehicle is 0, so that whether the ground clearance occurs or not can be judged more accurately. The off-ground detection scheme can be realized only by a very simple structure, and has high detection sensitivity and accuracy. Meanwhile, the motor controller and the IMU sensor matched with the hub motor are adopted in the detection method, the detection precision is high, the judgment error can be avoided to a large extent, and the rapid decision can be realized for vehicles with wheel layout forms of four wheels, six wheels, eight wheels and the like.

Drawings

Fig. 1 is a schematic structural diagram of the system provided by the present invention.

Detailed Description

The technical solutions of the present invention will be described clearly and completely with reference to the accompanying drawings, and it should be understood that the described embodiments are some, but not all embodiments of the present invention. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.

The invention provides a special vehicle liftoff detection system, as shown in fig. 1, the system specifically includes:

the motor controller is used for detecting the torques of the plurality of hub motors in real time and transmitting detected torque signals to the signal processing unit;

the inertia measurement unit is used for detecting the horizontal acceleration of the wheel in real time and transmitting a detected horizontal acceleration signal to the signal processing unit;

when the motor controller detects that the torque of the in-wheel motor has a step signal, the signal processing unit judges whether the vehicle is lifted off the ground or not based on the step signal and the horizontal acceleration signal, and sends a torque control signal to the motor controller to perform torque adjustment on the in-wheel motor.

On the basis of the design of the system, a liftoff detection method of the vehicle under the condition of driving skid resistance is also considered. When the vehicle is started, the driving antiskid strategy of the vehicle runs in real time, and the signal processing unit determines that the corresponding wheel lifts off the ground when the torque signals of part of the hub motors have step signals from positive to negative. . When the vehicle is empty, the wheels spin, and under the action of a driving anti-skid strategy, the driving force of the wheels is reduced, and the corresponding motor torque is reduced. The torque of the motor at the current moment must be smaller than the torque of the motor at the previous moment, and a step signal from positive to negative is generated in the control system.

The ground driving force, the rolling resistance, the slope resistance and the rolling moment of wheels of the vehicle are all generated when the vehicle runs on the ground, and when the vehicle is empty, the ground driving force, the rolling resistance, the slope resistance and the rolling of the wheels are all 0. The moon environment is free of air, and the air resistance is 0. Therefore, when the vehicle is empty, the acceleration of the entire vehicle is 0, and the acceleration of the vehicle in the horizontal direction is also 0. In order to ensure the detection accuracy, in the implementation, the horizontal acceleration of the vehicle is a 0 signal, and the negative torque step signals of all hub motors are simultaneously generated, so that the system can be detected from the ground. Therefore, when the torque signals of all the in-wheel motors simultaneously generate step signals from positive to negative, the judgment is carried out according to the horizontal acceleration, and if the horizontal acceleration is 0 at the moment, the situation that all the wheels are emptied and the vehicle is lifted off is determined. When the vehicle is in an empty state, the driving force can continuously decline under the action of a driving anti-skidding strategy, a negative torque step signal exists all the time, a main loop program executes calculation once within 10ms in a signal processing unit, and when the program executes 20 times, namely the duration time of the step signal reaches 0.2S, a ground-off early warning signal is sent out to remind a driver.

In the corresponding method for detecting the liftoff of the special vehicle by utilizing the system, the torques of the hub motors are detected in real time, and detected torque signals are transmitted to the signal processing unit; detecting the horizontal acceleration of the wheels in real time, and transmitting a detected horizontal acceleration signal to the signal processing unit; and the signal processing unit judges whether the vehicle is lifted off the ground or not based on the step signal and the horizontal acceleration signal when the motor controller detects that the torque of the in-wheel motor has the step signal, and sends a torque control signal to adjust the torque of the in-wheel motor.

The method is not only suitable for the situation that no one or a vehicle automatically runs, but also suitable for the situation that a person drives, and the detection result of the off-ground is provided for the driver, so that the driver can conveniently and autonomously carry out necessary operation control. The specific conversion method of the signal processing unit in this case is as follows: when the signal processing unit does not receive the negative torque step signals of all the motor torques and the signals that the horizontal acceleration is 0 at the same time, the signals are converted into a signal to be sent to the display screen, and the display screen displays that the vehicle is in a ground normal driving state, namely, the lunar rover is not lifted off the ground. When the signal processing unit receives negative torque step signals of all the motor torques and signals with the horizontal acceleration of 0 at the same time, the energy-off detection system starts to time, and when the duration time of the step signals of all the motors exceeds 0.2s, the signal processing unit gives a warning signal to the display screen to warn a driver that the vehicle is empty.

It should be understood that, the sequence numbers of the steps in the embodiments of the present invention do not mean the execution sequence, and the execution sequence of each process should be determined by the function and the inherent logic of the process, and should not constitute any limitation on the implementation process of the embodiments of the present invention.

Although embodiments of the present invention have been shown and described, it will be appreciated by those skilled in the art that various changes, modifications, substitutions and alterations can be made in these embodiments without departing from the principles and spirit of the invention, the scope of which is defined in the appended claims and their equivalents.

Claims

1. A method for detecting the liftoff of a special vehicle by using a liftoff detection system of the special vehicle is characterized by comprising the following steps:

the special vehicle liftoff detection system specifically includes:

the system comprises a plurality of hub motors, a motor controller, an inertia measurement unit and a signal processing unit;

when the motor controller detects that the torque of the in-wheel motor has a step signal, the signal processing unit judges whether the vehicle is lifted off the ground or not based on the step signal and the horizontal acceleration signal, and sends a torque control signal to the motor controller to perform torque adjustment on the in-wheel motor;

the step of judging whether the vehicle is lifted off the ground by the signal processing unit specifically comprises the following steps: when the torque signals of part of the hub motors have positive-to-negative step signals, determining that the corresponding wheel lifts off the ground; when the torque signals of all the hub motors simultaneously generate step signals from positive to negative, judging according to the horizontal acceleration, and if the horizontal acceleration is 0, determining that all the wheels are emptied and the vehicle is lifted off;

the method specifically comprises the following steps:

detecting the torques of the hub motors in real time, and transmitting detected torque signals to the signal processing unit;

and when the motor controller detects that the torque of the in-wheel motor has a step signal, the signal processing unit judges whether the vehicle is lifted off the ground or not based on the step signal and the horizontal acceleration signal, and sends a torque control signal to adjust the torque of the in-wheel motor.

2. The method of claim 1, wherein: for a special vehicle driven by a person, the signal processing unit sends out a display signal for warning the driver when the vehicle leaves the ground, and prompts the driver to execute necessary operation.