A load current monitoring control method and system for a six-wheel drive chassis

Abstract

The present application relates to the technical field of robot control, and especially to a load current monitoring control method and system of a six-wheel drive chassis. The present application proposes a load current monitoring control method of a six-wheel drive chassis, which completes the control of the chassis drive mode through the monitoring of the load current. The chassis has two main control drive wheels and four auxiliary drive wheels, each of which can be independently driven. In the case of light load, the two main drive wheels are differentially driven, and the auxiliary drive wheels are used as auxiliary wheels. When the two main drive wheels are differentially driven, the differential steering or the uncoordinated movement of the front and rear wheels can be avoided to cause the slip or sliding of the wheels, thereby improving the control accuracy and reducing the power consumption. Meanwhile, when the main wheels are overloaded, suspended or slipping, the main wheel current and speed can be monitored, the auxiliary drive wheels are controlled to work, and the six-wheel drive state is entered. The six-wheel drive state can fully exert the advantages of the six-wheel drive chassis in high load and strong driving force, and timely escape from the predicament. The method can ensure a certain working capacity of the chassis in a complex working environment.

Description

Technical Field

[0001] This invention relates to the field of robot control technology, and in particular to a load current monitoring and control method and system for a six-wheel drive chassis. Background Technology

[0002] A six-wheel drive chassis is a mobile platform that carries the robot's main body. It uses an electric drive motor to propel the chassis. Compared to two-wheel drive and four-wheel drive chassis, six-wheel drive chassis have stronger driving force and load capacity, but they also consume more energy. Furthermore, the differential steering of a six-wheel chassis is prone to wheel slippage, which leads to a series of problems such as further increased energy consumption, increased tire wear, and decreased control precision.

[0003] Existing six-wheel drive chassis partially utilize electronic or mechanical real-time control systems. These systems can automatically change the drive mode when slippage occurs via mechanical structures. They are simple in structure and do not require electronic intervention, but their control precision is poor and their latency is large, making them unsuitable for precision control. Alternatively, a method can be used to calculate the lateral and longitudinal torques of the motors and then adjust the chassis movement by controlling the torque distribution. This method can enhance motion stability and has advantages such as reducing steering resistance, improving control precision, and optimizing energy consumption. However, the torque calculation and distribution control methods are relatively complex and difficult to implement. Summary of the Invention

[0004] To overcome the shortcomings of low control accuracy or complex operation of six-wheel drive chassis in the prior art, this invention proposes a load current monitoring and control method for six-wheel drive chassis, realizing high-precision automated control of six-wheel drive chassis.

[0005] This invention proposes a load current monitoring and control method for a six-wheel drive chassis. The six wheels of the six-wheel drive chassis are arranged in two columns and three rows, with the two wheels in the middle row being the main drive wheels and the remaining four wheels being the auxiliary wheels. The main drive wheels are each connected to a main drive motor that provides kinetic energy. The auxiliary wheels are connected to corresponding auxiliary motors through clutches.

[0006] The load current monitoring and control method for the six-wheel drive chassis includes the following steps:

[0007] S1. Monitor the load current value I of the main drive motor. a The load current value I of each main drive motor is... a Respectively compared with the light load current threshold K a I n and the heavy load current threshold K b I n Compare; K a K is the light load current coefficient. b I is the heavy-load current coefficient. nRated current of the drive motor; 0 <K a <1 <K b ;

[0008] S2, when the load current I of the main drive motors on both sides a All satisfy I a <K a I n If the chassis is under light load, the auxiliary wheels will be disengaged from the auxiliary motor.

[0009] S3, when the load current I of the two main drive motors a All satisfy K a I n ≤I a ≤K b I n If the chassis is under normal load, each auxiliary wheel is connected to the corresponding auxiliary motor, and each main drive motor and each auxiliary motor is controlled to execute the target speed n.

[0010] S4, when the main drive motor on either side meets its load current I a >K b I n Then the torque of the main drive motor of the main drive wheel on that side is adjusted to the target torque T. em Then connect the auxiliary motor on that side to the corresponding auxiliary wheel, and adjust the torque of the auxiliary motor to the target torque T. em ;

[0011] S5, when both main drive wheels on both sides meet the load current I a >K b I n First, adjust the torque of the two main drive motors to T. em Connect each auxiliary motor to its corresponding auxiliary wheel, and then adjust the torque of the auxiliary motor to T. em .

[0012] Preferably, in S3, the formula for calculating the target rotational speed n is:

[0013]

[0014] Φ=k f I a

[0015] Where n is the motor speed, U N I is the rated voltage of the motor. a To measure the load current of the main drive motor, R a C is the rated resistance of the motor. e Φ is the motor speed coefficient, Φ is the magnetic flux, and k is the magnetic flux density. f This is the motor excitation coefficient.

[0016] Preferably, the target torque T in S4 em The calculation formula is as follows:

[0017] T em =C T ΦI a

[0018] T em C is the motor torque. T Φ is the torque coefficient, and Φ is the magnetic flux.

[0019] Preferably, 0.5 ≤ K a ≤0.7, 1.2≤K b ≤1.7.

[0020] The present invention proposes a load current monitoring and control system for a six-wheel drive chassis, comprising: a controller, a main drive servo driver, an auxiliary servo driver, and a current detector; the main drive servo driver is connected to the main drive motor in a one-to-one correspondence, and the auxiliary servo driver is connected to the auxiliary motor in a one-to-one correspondence; the current detector is connected to the main drive motor in a one-to-one correspondence; the controller is connected to each main drive servo driver, auxiliary servo driver, and current detector respectively.

[0021] The current detector is used to detect the load current of the corresponding main drive motor. The controller obtains the detection result of the current detector and determines the chassis load condition based on the load current detection results of the two main drive motors. Based on the chassis load condition, the controller sends control commands to each main drive servo driver and auxiliary servo driver respectively. The main drive servo driver controls the corresponding main drive motor to work according to the received control command, and the auxiliary servo driver controls the corresponding load motor to work according to the received control command, so as to realize the load current monitoring and control method of the six-wheel drive chassis.

[0022] Preferably, the controller is connected to the main drive servo driver and the auxiliary servo driver respectively via a CAN bus.

[0023] Preferably, the controller is connected to the current detector via an ADC interface.

[0024] The present invention proposes a load current monitoring and control system for a six-wheel drive chassis, comprising a memory and a processor. The memory stores a computer program, and the processor is connected to the memory. The processor executes the computer program to implement the load current monitoring and control method for the six-wheel drive chassis.

[0025] The present invention proposes a storage medium storing a computer program, which, when executed, is used to implement the load current monitoring and control method for the six-wheel drive chassis.

[0026] The advantages of this invention are:

[0027] (1) This invention proposes a load current monitoring and control method for a six-wheel drive chassis, which controls the chassis drive mode by monitoring the load current. The chassis has two main drive wheels and four auxiliary drive wheels, each of which can be driven independently. Under light load conditions, the main drive wheels drive at a two-wheel drive differential speed, while the auxiliary drive wheels act as auxiliary wheels. In two-wheel drive mode, this avoids wheel slippage or drift caused by differential steering or uncoordinated movement of the front and rear wheels, thus improving control accuracy and reducing power consumption. At the same time, this method can monitor the current and speed of the main wheels when the main wheels are overloaded, suspended, or slipping, and control the auxiliary drive wheels to enter a six-wheel drive state. The six-wheel drive state can fully utilize the advantages of the high load and strong driving force of the six-wheel drive chassis, allowing it to escape from difficult situations in a timely manner. This method enables the chassis to maintain a certain working capacity in complex working environments.

[0028] (2) The load current monitoring and control method proposed in this invention uses a current monitoring system to monitor the load current of the main drive wheel in real time. Based on the changes in the load current of the main drive wheel, the chassis motion status is determined, thereby selecting three different control modes. This improves the chassis's motion performance and broadens its application scenarios. Speed ​​control balances the drive motor torque, preventing overload of a single drive wheel. Simultaneously, adjusting the load current optimizes motor energy consumption, improving the chassis's range.

[0029] (3) The chassis drive mode is adjusted by monitoring the real-time load current changes of the main drive wheels. Under light load, the chassis optimizes to reduce power consumption and maximize operating efficiency, and the main drive wheels enter a two-wheel drive differential driving mode, which reduces energy consumption and improves control accuracy. Under normal load conditions, the chassis optimizes to ensure stable operation, and the speed / torque of the motors on the same side is balanced according to the load current to ensure stable operation. Under heavy load conditions, the chassis optimizes to balance motor torque and reduce losses, and the speed / torque of each motor is dynamically allocated by monitoring the current of each motor. The method of this invention allows the chassis to select different control modes under different operating conditions, avoiding the steering slippage and high energy consumption problems of six-wheel drive, while making the chassis more adaptable. Attached Figure Description

[0030] Figure 1 A flowchart of a load current monitoring and control method for a six-wheel drive chassis;

[0031] Figure 2 This is a schematic diagram of a six-wheel drive chassis, where 1 is the chassis, 2 is the main drive wheel, and 3 is the auxiliary wheel;

[0032] Figure 3 For chassis communication and control network;

[0033] Figure 4This is a DC motor efficiency-load current curve.

[0034] Figure 5 This is a graph showing the torque / speed versus load current of a DC motor. Detailed Implementation

[0035] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0036] like Figure 2 As shown, the six wheels of the six-wheel drive chassis are arranged in two columns and three rows. The two wheels in the middle row are the main drive wheels, and the remaining four wheels are the auxiliary wheels. The main drive wheels are connected to the main drive motors that provide kinetic energy. The auxiliary wheels are connected to the corresponding auxiliary motors through clutches.

[0037] Each main drive wheel corresponds to a main drive motor, and each auxiliary wheel corresponds to an auxiliary motor. During the movement of the six-wheel drive chassis, the main drive wheels are always connected to their corresponding main drive motors, which drive the main drive wheels to rotate. The auxiliary wheels have two operating states: first, the auxiliary wheel is connected to its corresponding auxiliary motor, which drives the auxiliary wheel to rotate; second, the auxiliary wheel is not connected to an auxiliary motor, and the main drive wheels drive the auxiliary wheel to rotate.

[0038] like Figure 1 , Figure 4 As shown in the figure, the load current monitoring and control method for a six-wheel drive chassis proposed in this embodiment includes the following steps S1-S4.

[0039] S1. Set the range of load current values ​​for the drive motor when the chassis load is normal, denoted as [K]. a I n K b I n ], K a and K b K is a parameter for motor efficiency. a K is the light load current coefficient. b The overload current coefficient is 0. <K a <1 <K b ;I n The rated current value of the drive motor; monitor the load current value I of the main drive motor connected to the main drive wheel. a In practice, K a K can take values ​​in the interval [0.5, 0.7]. b It can take values ​​in the interval [1.2, 1.7].

[0040] S2, when the load current I of the main drive motors on both sides a All satisfy I a <K a I n If the chassis is under light load, then the two-wheel differential mode is adopted, and the auxiliary wheel is disengaged from the auxiliary motor.

[0041] Thus, under light load conditions, with the optimization goal of reducing power consumption and maximizing operating efficiency, the main drive wheels enter a two-wheel drive differential driving mode, which reduces energy consumption while improving control precision.

[0042] S3, when the load current I of the two main drive motors a All satisfy K a I n ≤I a ≤K b I n If the chassis is under normal load, then the optimization goal is to ensure stable operation. The speed / torque of the main drive motor and the auxiliary motor on the same side is balanced according to the load current.

[0043] In this embodiment, under normal load conditions, each auxiliary wheel is connected to a corresponding auxiliary motor, and the speed of the main drive motor and the auxiliary motor are controlled according to the following formula;

[0044]

[0045] Φ=k f I f =k f I a (2)

[0046] Where n is the motor speed, U N I is the rated voltage of the motor. a To measure the load current of the main drive motor, R a C is the rated resistance of the motor. e Φ is the motor speed coefficient, Φ is the magnetic flux, and the magnitude of the magnetic flux is the excitation current I. f With excitation coefficient k f The product of I f =I a .

[0047] S4. When the main drive motor on one side meets its load current I a >K b I n Then the torque of the main drive motor of the main drive wheel on that side is adjusted to T. em Connect the auxiliary motor on that side to the corresponding auxiliary wheel, and adjust the torque of the auxiliary motor to T. em ;

[0048] When both main drive wheels on both sides meet the load current I a >K b I n First, adjust the torque of the two main drive motors to T. em Connect each auxiliary motor to its corresponding auxiliary wheel, and then adjust the torque of the auxiliary motor to T. em .

[0049] T em =C T ΦI a

[0050] T em C is the motor torque. T Φ is the torque coefficient, and Φ is the magnetic flux.

[0051] In this embodiment, as long as the load current of either main drive motor exceeds the heavy load current threshold K... b I n If the six-wheel drive chassis is under heavy load, the auxiliary wheel on the corresponding side will be connected to the auxiliary motor to balance the motor torque and reduce motor efficiency loss.

[0052] Reference Figure 3 This embodiment proposes a load current monitoring and control system for a six-wheel drive chassis, which is used to control the movement of the six-wheel drive chassis. The main drive wheels are connected to corresponding main drive motors, the auxiliary motors are connected to corresponding auxiliary motors, and each motor is connected to a corresponding servo driver, which controls the operation of the motor.

[0053] Specifically, the main drive motor is connected to a main drive servo driver, and the auxiliary motor is connected to an auxiliary servo driver.

[0054] The control system also includes a controller and current detectors corresponding to the main drive motors. The current detectors are used to detect the load current of the corresponding main drive motors. The controller determines the chassis load condition based on the load current of the two main drive motors and generates corresponding control commands based on the load condition. The servo driver controls the corresponding motor to work according to the commands issued by the controller, so as to realize the wheel drive mode under the corresponding load condition.

[0055] In this embodiment, the current detector periodically collects the voltage of the main drive motor. The controller receives the sampled voltage information through the ADC channel, filters the sampled voltage information, calculates the load current of the main drive motor, and sends control commands to each servo driver through the CAN network to control the motor operation.

[0056] In practical implementation, the main drive motor can be a DC motor, and its efficiency-load current curve and torque / speed-load current curve are as follows: Figure 4 , Figure 5 As shown.

[0057] Of course, those skilled in the art will recognize that the present invention is not limited to the details of the exemplary embodiments described above, but also includes the same or similar structures that can be implemented in other specific forms without departing from the spirit or essential characteristics of the invention. Therefore, the embodiments should be considered illustrative and non-limiting in all respects, and the scope of the invention is defined by the appended claims rather than the foregoing description. Thus, all variations falling within the meaning and scope of equivalents of the claims are intended to be included within the present invention. No reference numerals in the claims should be construed as limiting the scope of the claims.

[0058] Furthermore, it should be understood that although this specification describes embodiments, not every embodiment contains only one independent technical solution. This narrative style is merely for clarity. Those skilled in the art should consider the specification as a whole, and the technical solutions in each embodiment can also be appropriately combined to form other embodiments that can be understood by those skilled in the art.

[0059] The technologies, shapes, and structures not described in detail in this invention are all known technologies.

Claims

1. A load current monitoring and control method for a six-wheel drive chassis, wherein the six wheels of the six-wheel drive chassis are arranged in two columns and three rows, wherein the two wheels in the middle row are the main drive wheels, and the remaining four wheels are the auxiliary wheels; the main drive wheels are respectively connected to a main drive motor that provides kinetic energy; the auxiliary wheels are connected to corresponding auxiliary motors through clutches; Its features are, The load current monitoring and control method for the six-wheel drive chassis includes the following steps: S1. Monitor the load current value I of the main drive motor. a The load current value I of each main drive motor is... a Respectively compared with the light load current threshold K a I n and the heavy load current threshold K b I n Compare; K a K is the light load current coefficient. b I is the heavy-load current coefficient. n Rated current value of the drive motor; 0 < K a <1<K b ; S2, when the load current I of the main drive motors on both sides a All satisfy I a <K a I n If the chassis is under light load, the auxiliary wheels will be disengaged from the auxiliary motor. S3, when the load current I of the two main drive motors a All satisfy K a I n ≤I a ≤K b I n If the chassis is under normal load, each auxiliary wheel is connected to its corresponding auxiliary motor, controlling the main drive motor and each auxiliary motor to achieve the target speed. n ; S4, when the main drive motor on either side meets its load current I a >K b I n Then the torque of the main drive motor of the main drive wheel on that side is adjusted to the target torque T. em Then connect the auxiliary motor on that side to the corresponding auxiliary wheel, and adjust the torque of the auxiliary motor to the target torque T. em ; S5, when both main drive wheels on both sides meet the load current I a >K b I n First, adjust the torque of the two main drive motors to T. em Connect each auxiliary motor to its corresponding auxiliary wheel, and then adjust the torque of the auxiliary motor to T. em .

2. The load current monitoring and control method for a six-wheel drive chassis as described in claim 1, characterized in that, In S3, the formula for calculating the target rotational speed n is: Φ=k f I a Where n is the motor speed, U N I is the rated voltage of the motor. a To measure the load current of the main drive motor, R a C is the rated resistance of the motor. e Φ is the motor speed coefficient, Φ is the magnetic flux, and k is the magnetic flux density. f This is the motor excitation coefficient.

3. The load current monitoring and control method for a six-wheel drive chassis as described in claim 2, characterized in that, The target torque T in S4 em The calculation formula is as follows: T em =C T ΦI a T em C is the motor torque. T Φ is the torque coefficient, and Φ is the magnetic flux.

4. The load current monitoring and control method for a six-wheel drive chassis as described in claim 1, characterized in that, 0.5≤K a ≤0.7,1.2≤K b ≤1.7。 5. A load current monitoring and control system for a six-wheel drive chassis, characterized in that, include: The system includes a controller, a main drive servo driver, an auxiliary servo driver, and a current detector; the main drive servo driver is connected to the main drive motor in a one-to-one correspondence, and the auxiliary servo driver is connected to the auxiliary motor in a one-to-one correspondence. Each current detector is correspondingly connected to a main drive motor; The controller is connected to each main drive servo driver, auxiliary servo driver, and current detector respectively; The current detector is used to detect the load current of the corresponding main drive motor. The controller obtains the detection result of the current detector, and judges the chassis load condition based on the load current detection results of the two main drive motors. Based on the chassis load condition, the controller sends control commands to each main drive servo driver and auxiliary servo driver respectively. The main drive servo driver controls the corresponding main drive motor to work according to the received control command, and the auxiliary servo driver controls the corresponding load motor to work according to the received control command, so as to realize the load current monitoring and control method of the six-wheel drive chassis as described in any one of claims 1-4.

6. The load current monitoring and control system for a six-wheel drive chassis as described in claim 4, characterized in that, The controller is connected to the main servo driver and the auxiliary servo driver via a CAN bus.

7. The load current monitoring and control system for a six-wheel drive chassis as described in claim 4, characterized in that, The controller is connected to the current detector via an ADC interface.

8. A load current monitoring and control system for a six-wheel drive chassis, characterized in that, It includes a memory and a processor. The memory stores a computer program, and the processor is connected to the memory. The processor is used to execute the computer program to implement the load current monitoring and control method for a six-wheel drive chassis as described in any one of claims 1-4.

9. A storage medium, characterized in that, The system contains a computer program that, when executed, implements the load current monitoring and control method for a six-wheel drive chassis as described in any one of claims 1-4.

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