A motor control method and system for a high aerial work platform to suppress sway

Abstract

This invention discloses a motor control method, or system, for suppressing swaying in aerial work platforms. The method includes: acquiring human-operated speed command data from a joystick sensor; preprocessing the acquired raw data on the swaying state of the suspended platform to obtain swaying state data; the swaying state data includes the angular velocity and acceleration of the three axes of the suspended platform; identifying the swaying state based on the obtained swaying state data and generating a sway suppression command; fusing the sway suppression command and the human-operated speed command to obtain a final speed command, and limiting the final speed command according to the vehicle status; generating the required motor torque command based on the received final speed command, converting it into a motor drive signal to control the chassis motor to perform the operation; and generating a sway suppression force that causes the chassis to move laterally or rotate through differential control of the travel motor, which is transmitted to the suspended platform through the boom to counteract the original swaying and achieve active sway suppression.

Description

Technical Field

[0001] This invention belongs to the field of aerial work platforms, and particularly relates to a motor control method and system for suppressing swaying in aerial work platforms. Background Technology

[0002] Currently, aerial work platforms are widely used in construction, municipal maintenance, power emergency repair, logistics and warehousing, and other fields. However, with increased working height and boom length, the rigidity of the equipment decreases. Combined with external disturbances such as wind loads, ground impacts, and inertia, the platform's swaying amplitude increases significantly. For example, the boom of a telescopic aerial work platform is prone to vibration during luffing, threatening the safety of workers. Swaying not only increases the risk of workers falling and tools dropping, but also reduces working accuracy, forcing operators to reduce working speed and affecting construction efficiency. Furthermore, long-term vibration accelerates fatigue damage to the boom structure, shortening the equipment's service life.

[0003] The patent application CN202321243620.9, entitled "A High-Altitude Work Platform with Anti-Sway Function," addresses the problem of swaying that may occur when the lift is blown by wind during operation of existing high-altitude work platforms by using a transmission screw and threaded sleeve. While this technical solution can prevent swaying to a certain extent, the transmission ratio and stroke of the mechanical anti-sway structure are fixed, and the cooperation between the screw and threaded sleeve cannot be changed independently. In weak winds, excessive mechanical adjustment may cause the platform to stiffen; in strong winds or sudden load changes, the limited adjustment range cannot effectively suppress swaying; and the frequency and amplitude of swaying change as the work platform is raised or lowered to different heights, making it impossible for the mechanical structure to adapt accordingly. Summary of the Invention

[0004] The purpose of this invention is to provide a motor control method and system for suppressing swaying in aerial work platforms. By driving the chassis travel motor to generate active sway suppression action, the invention solves the problem of continuous and dangerous swaying of the suspended platform (work platform) caused by wind, personnel movement, or boom start-stop impact during operation.

[0005] This invention adopts the following technical solution: a motor control method for suppressing swaying in aerial work platforms, comprising:

[0006] S1: Collect and acquire the human-operated speed command data from the joystick sensor, and preprocess the collected raw data of the basket's swaying state to obtain the basket's swaying state data; the basket's swaying state data includes the basket's three-axis angular velocity and three-axis acceleration;

[0007] S2: Identify the swaying state of the suspended basket based on the obtained swaying state data and generate a sway suppression command;

[0008] S3: The sway suppression command and the manually controlled speed command are fused to obtain the final speed command, and the final speed command is limited according to the vehicle status.

[0009] S4: Generates the required motor torque command based on the received final speed command, and converts it into a motor drive signal to control the chassis motor to perform operations.

[0010] Furthermore, the S2 generates a sway suppression command, which includes the following steps: the sway suppression command includes a sway suppression acceleration;

[0011] S201: The data on the swaying state of the suspended platform are fused and processed to calculate the angle data of the suspended platform relative to the horizontal plane;

[0012] S202: Perform high-pass filtering on the acquired angle data and sway state data of the suspended platform to obtain the filtered sway angle and angular velocity, and calculate the real-time angular acceleration of the suspended platform.

[0013] S203: The type of sway is determined by comparing the calculated real-time angular acceleration of the suspended platform with the angular acceleration safety threshold of the suspended platform;

[0014] When the swaying of the suspended platform is determined to be dangerous, a safety response is triggered.

[0015] If the swaying of the suspended platform is determined to be normal swaying, proceed to step S204;

[0016] S204: The sway suppression acceleration in the sway suppression command is calculated based on the filtered sway angle and angular velocity of the suspended basket.

[0017] Furthermore, S201 uses the quaternion method or complementary filtering algorithm to fuse the three-axis angular velocity and three-axis acceleration in the hoist sway state data, and after calculation, obtains the real-time roll angle and real-time pitch angle data of the hoist relative to the horizontal plane.

[0018] Furthermore, in S204, based on the filtered swing angle and angular velocity of the basket, the PD control law is applied to the constructed equivalent inverted pendulum dynamic model to obtain the sway-suppressing acceleration.

[0019] Furthermore, the equivalent inverted pendulum dynamic model maps the chassis-boom-suspension basket of the aerial work platform vehicle to an equivalent inverted pendulum model. The suspension basket is equivalent to a pendulum at the top of the pendulum rod, the boom is equivalent to a massless rigid pendulum rod of length L, and the contact point between the chassis and the ground is regarded as the fulcrum of the pendulum.

[0020] Furthermore, in step S3, the sway suppression command from step S3 and the manual control speed command from the joystick sensor are fused to obtain the final speed command. The process is as follows:

[0021] S301: Calculate the dynamic weighting factor corresponding to the sway suppression acceleration and the manually controlled speed command;

[0022] S302: Convert the sway-suppressing acceleration into sway-suppressing velocity, and fuse the manually manipulated speed command with the sway-suppressing velocity based on the dynamic weighting factor to obtain the final speed command.

[0023] Furthermore, in step S301, the dynamic weighting factor is calculated based on the amplitude of the manually controlled speed command according to the following principles:

[0024] When the amplitude of the manually manipulated speed command is less than the first amplitude threshold, the dynamic weighting factor is set to 1;

[0025] When the amplitude of the manually manipulated speed command exceeds the second amplitude threshold, the dynamic weighting factor is set to 0.

[0026] When the amplitude of the manually manipulated speed command is greater than or equal to the first amplitude threshold and less than or equal to the second amplitude threshold, the magnitude of the dynamic weighting factor is based on linear interpolation and takes a value between 0.0 and 1.0.

[0027] Furthermore, the final speed command is limited based on the vehicle's status.

[0028] A. Establish a two-dimensional lookup table based on the input variables boom length and the angle between the boom and the horizontal plane to obtain the maximum permissible lateral acceleration and maximum permissible lateral velocity corresponding to the posture;

[0029] B. Read the current boom length and the angle between the boom and the horizontal plane from the boom sensor. Using the current boom length and the angle between the boom and the horizontal plane as indexes, query the maximum permissible lateral acceleration and the maximum permissible lateral velocity under the current working condition from the pre-stored two-dimensional lookup table.

[0030] Furthermore, S4 controls the chassis motor to perform operations.

[0031] S401: Decompose the final speed command into the target speeds of the vehicle's moving wheels;

[0032] The process includes the following steps: the target speed of the vehicle's moving wheels includes the target speed of the left wheel and the target speed of the right wheel; the chassis sway angular acceleration required for sway suppression is obtained based on the sway suppression acceleration and the horizontal projection length of the boom; the chassis sway angular acceleration is integrated to obtain the chassis sway angular velocity required for sway suppression; and the target speeds of the left and right wheels are calculated based on the final speed command and the chassis sway angular velocity.

[0033] S402: Generates the required motor torque command based on the actual speed of the target speed and converts it into a motor drive signal;

[0034] The speed error is calculated based on the target speed and the actual speed. A PI control algorithm is applied to the speed error to obtain the motor torque command. The motor torque command is then converted into a PWM wave motor drive signal, which drives the left and right travel motors through the motor driver.

[0035] A motor control system for suppressing swaying in aerial work platforms includes: a data acquisition module, a decision control module, a command fusion module, and an execution module; wherein,

[0036] The data acquisition module is used to acquire and transmit the human-operated speed command data from the joystick sensor to the command fusion module, and to acquire the raw data of the basket's swaying state and transmit the preprocessed data of the basket's swaying state to the decision control module.

[0037] The decision control module is used to identify the swaying state of the suspended basket based on the swaying state data and generate sway suppression commands, which include sway suppression acceleration and sway suppression speed.

[0038] The command fusion module is used to fuse the sway suppression command from the decision control module with the human control command from the joystick sensor to obtain the final speed command, and transmit the final speed command to the execution module; and to perform amplitude limiting processing on the final speed command according to the vehicle status; the human control command includes the human control speed command;

[0039] The execution module is used to generate the required motor torque command based on the received final speed command, and convert it into a motor drive signal to control the chassis motor to perform operations.

[0040] This invention generates a sway-suppressing force that causes the chassis to move laterally or rotate based on the driving or braking force generated by the left and right travel motors. This force is transmitted to the basket through the boom to counteract the original swaying and achieve active sway suppression. In addition, the motor status data, including the actual speed and torque, is fed back to the decision control module to form a closed-loop control.

[0041] This invention uses a control law based on an equivalent inverted pendulum model to directly control a walking motor with extremely fast response speed. The calculation is simple and can achieve real-time control. The effect of the chassis translational motion on the suspended platform is direct and linear, avoiding the nonlinear coupling problem of the boom motion.

[0042] This invention achieves direct monitoring of the sway suppression target by directly installing an inertial measurement unit on the suspended platform. The control target is the attitude stability of the suspended platform, rather than the stability of the chassis. Therefore, the system can intervene at the initial stage of swaying, at the moment a tiny angle of the suspended platform is detected, eliminating the risk in its infancy. Furthermore, it requires minimal modification to the vehicle's mechanical structure and is easy to implement.

[0043] This invention achieves full automation of the sway suppression process. The command fusion technology ensures that the system will not interfere with the operator's normal driving intentions during sway suppression, achieving imperceptible sway suppression. In addition, the operator can operate the system as if it were a normal stable vehicle, without having to change their habits. Attached Figure Description

[0044] To more clearly illustrate the technical solutions in the embodiments of the present invention or related technologies, the drawings used in the description of the embodiments or related technologies will be briefly introduced below. Obviously, the drawings described below are only embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on the provided drawings without creative effort.

[0045] Figure 1 This is a flowchart illustrating the motor control method for suppressing swaying in aerial work platforms according to the present invention.

[0046] Figure 2 This is a flowchart of the motor control system for suppressing swaying on an aerial work platform according to the present invention. Detailed Implementation

[0047] To make the objectives, technical solutions, and advantages of the embodiments described herein clearer, the technical solutions in the embodiments will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only a part of the embodiments described herein, not all of them. All other embodiments obtained by those skilled in the art based on the embodiments described herein without creative effort are within the scope of protection of this document. It should be noted that, unless otherwise specified, the embodiments and features described herein can be arbitrarily combined with each other.

[0048] The following is in conjunction with the appendix Figure 1 , two The present invention will be described in detail with reference to the embodiments:

[0049] A motor control method for suppressing swaying in aerial work platforms includes the following processes:

[0050] S1: Obtain the human control speed command from the joystick sensor via the data acquisition module. The data is transmitted to the instruction fusion module, which transmits the pre-processed raw data of the suspended platform swaying state collected by the data acquisition module to the decision control module.

[0051] In this invention, the inertial measurement unit in the data acquisition module collects the swaying state data of the suspended platform in real time at a sampling frequency of 100-500Hz; the swaying state data of the suspended platform includes the three-axis angular velocities of the suspended platform. and triaxial acceleration .

[0052] In this embodiment, the geometric center of the suspended platform or the installation point of the inertial measurement unit in the data acquisition module is taken as the origin of the coordinate system; the Z-axis is perpendicular to the plane of the suspended platform and points vertically upward (opposite to the direction of gravity); the X-axis is located in the plane of the suspended platform and points in front of the suspended platform (i.e., the front of the vehicle when it is driving normally, pointing towards the front of the vehicle); and the Y-axis is located in the plane of the suspended platform and is determined by the right-hand rule, pointing to the left side of the suspended platform. Together with the X-axis and Z-axis, they form a coordinate system that is perpendicular to each other.

[0053] The triaxial angular velocity represents the rate of rotation of the suspended platform around each coordinate axis, typically expressed in degrees per second or radians per second. The angular velocity around the X-axis... This indicates the rolling speed of the suspended platform; for example, the rotational speed of the platform as the left side moves upward and the right side moves downward; expressed as the angular velocity about the Y-axis. This indicates the pitch speed of the suspended platform; for example, the rotational speed at which the front of the suspended platform is lifted upwards or pressed downwards; or the angular velocity about the Z-axis. This indicates the yaw speed of the suspended platform; for example, the rotational speed at which the suspended platform swings left and right in the horizontal plane.

[0054] The three-axis acceleration represents the acceleration of the suspended platform along each coordinate axis, usually measured in meters per second², including the gravitational acceleration g; the linear acceleration along the X-axis is also considered. This represents the acceleration in the forward and backward direction of the suspended platform; this value is positive when the vehicle accelerates forward; it is the linear acceleration along the Y-axis. This represents the lateral acceleration of the suspended platform; the value is negative when the vehicle moves to the left; the acceleration is linear along the Z-axis. This represents the vertical acceleration of the suspended platform; when the platform is stationary, it represents the linear acceleration along the Z-axis. It is g (approximately +9.8 m / s²), used to counteract the downward force of gravity; the linear acceleration along the Z-axis when the basket accelerates upward. Greater than g.

[0055] In this embodiment, the raw data of the basket's swaying state is preprocessed. The preprocessing process includes signal filtering and coordinate transformation. Signal filtering is used to remove high-frequency noise, and coordinate transformation is used to convert the sensor coordinate system to the vehicle coordinate system. The preprocessed angular velocity is then transmitted via a CAN bus or SPI interface. and linear acceleration Transmitted to the decision control module.

[0056] S2: Identify the swaying state of the suspended platform based on the swaying state data obtained from the decision control module and generate a sway suppression command;

[0057] In this invention, the sway suppression command includes sway suppression acceleration. .

[0058] Specifically, the following steps are included:

[0059] S201: The data on the swaying state of the suspended platform are fused and processed to calculate the angle data of the suspended platform relative to the horizontal plane;

[0060] In this embodiment, the quaternion method or complementary filtering algorithm can be used to analyze the angular velocity in the swaying state data of the suspended basket. and linear acceleration After fusion processing, the real-time roll angle of the suspended platform relative to the horizontal plane is obtained after calculation. and pitch angle Data; Roll angle The tilt angle describing the basket's tilt around the X-axis (direction of travel) can be understood as the basket swaying left and right; pitch angle. The description of the tilt angle of the basket around the Y-axis (horizontal left) can be understood as the basket nodding or tilting its head.

[0061] Based on angular velocity and linear acceleration Obtaining quaternions using the quaternion method, and then solving the quaternions to further calculate Euler angles is a common technique in this field, which will not be elaborated here.

[0062] S202: Perform high-pass filtering on the acquired angle data and state data of the suspended platform sway to obtain the filtered angle of the suspended platform sway. and angular velocity ; Calculate the real-time angular acceleration of the suspended platform;

[0063] In this embodiment, the angle data generated by the swaying of the suspended basket includes the real-time roll angle. And real pitch angle The data, therefore, after high-pass filtering, yields the filtered real-time roll angle. And real pitch angle Data, swing angle of the suspended basket Including the filtered real-time roll angle And real pitch angle Data; the filter cutoff frequency is set to be greater than or equal to 0.1Hz and less than or equal to 0.5Hz to retain the high-frequency components representing harmful sloshing; the angular velocity is differentiated to obtain the angular acceleration.

[0064] S203: The type of sway is determined by comparing the calculated real-time angular acceleration with a preset angular acceleration safety threshold;

[0065] When the shaking is determined to be dangerous, a safety response is triggered.

[0066] If the shaking is determined to be normal shaking, proceed to the next step.

[0067] In this embodiment, angular acceleration reflects the sudden change in torque acting on the suspended platform and serves as an alarm signal to identify sudden and dangerous working conditions. Stable wind or slow personnel movement will produce a large sway angle and angular velocity, but its angular acceleration is usually small. However, a sudden gust of wind, falling objects, or accidental collision with obstacles will cause the suspended platform to generate a huge angular acceleration in an instant.

[0068] According to one specific embodiment, a safety threshold for angular acceleration is set to distinguish between normal swaying and dangerous impacts in real time. When the real-time angular acceleration is greater than the safety threshold, the swaying is determined to be dangerous, triggering a safety response; when the real-time angular acceleration is less than or equal to the safety threshold, the swaying is determined to be normal, and the next step is executed. The highest priority safety response is triggered, which may include applying the maximum sway-damping torque allowed by the system, issuing an audible and visual alarm, or advising the operator to retract the boom. The safety response is triggered when the swaying is determined to be dangerous, rather than following the conventional PD control law; this measure adds important active safety protection to the system.

[0069] According to another specific embodiment, a state observer (such as a Kalman filter) can also be used to estimate the system state. Estimation using a state observer is more accurate and noise-resistant; it is described by position (angle), velocity (angular velocity), and acceleration (angular acceleration). Angular acceleration serves as an input or verification value for the observer. The predicted angular acceleration for the next moment is compared with the actual measured or calculated angular acceleration. If the absolute value of the difference between the predicted and actual measured or calculated angular acceleration is greater than a safety threshold, the sway is determined to be dangerous, triggering a safety response and thus the aforementioned safety mechanism. If the absolute value of the difference between the predicted and actual measured or calculated angular acceleration is less than or equal to the safety threshold, the sway is determined to be normal. This improves the system's ability to perceive abnormal states.

[0070] S204: Calculate the sway-suppressing acceleration And transmit it to the instruction fusion module;

[0071] In this invention, the PD control law is applied to the equivalent inverted pendulum dynamic model in the algorithm unit to obtain the sway-suppressing acceleration. The formula is as follows:

[0072]

[0073] in: The filtered swing angle of the suspended basket. The filtered angular velocity, and These are pre-calibrated control parameters;

[0074] The larger the basket angle after proportional term filtering, the greater the output anti-sway acceleration, directly offsetting the deviation trend (e.g., when the fork tilt angle is too large, the hydraulic actuator provides backward acceleration to suppress tilting). The angular velocity after differential term filtering... Reflecting the rate of angle change, differential feedback can predict the trend of deviation changes. For example, if the fork tilts forward too quickly, the anti-sway acceleration can be increased in advance to avoid overshoot.

[0075] In this embodiment, the sway-suppressing accelerations are calculated separately for the lateral (i.e., X direction) and longitudinal (i.e. Y direction) directions.

[0076] Furthermore, the equivalent inverted pendulum dynamic model in the algorithm unit, based on the basket-boom structure, serves as the physical bridge connecting the basket's swaying and the chassis's motion. The chassis-boom-basket system of the aerial work platform is abstracted and simplified into an equivalent inverted pendulum model. The basket is represented as a concentrated mass block (pendulum) at the top of the pendulum rod, the boom as a massless rigid pendulum rod of length L, and the contact point between the chassis and the ground as the fulcrum of the pendulum. Dynamic equations are established based on this equivalent inverted pendulum dynamic model, mapping the basket's swaying state data to the chassis's sway-suppressing motion commands. Other models, such as simple PID control and fuzzy logic, cannot establish this cross-domain dynamic subsystem relationship, resulting in significantly degraded sway-suppressing effects.

[0077] S3: The command fusion module fuses the anti-sway command from the decision control module and the human control command from the joystick sensor, and performs amplitude limiting on the final speed command according to the vehicle status.

[0078] In this invention, the sway suppression command includes sway suppression acceleration. Human control commands include human control speed commands. Therefore, the sway suppression acceleration from the decision control module is integrated through the instruction fusion module. and human-controlled speed commands from the joystick sensor To merge;

[0079] The specific process is as follows:

[0080] S301: Calculate sway-suppressing acceleration and human-controlled speed commands Corresponding dynamic weighting factor ;

[0081] Based on the following principles and human-controlled speed commands amplitude Calculate dynamic weighting factors ,

[0082] When the speed command is manually controlled amplitude When it is less than the first amplitude threshold, that is At that time, full control over sway suppression will be applied to the dynamic weighting factor. Set to 1, ;

[0083] When the speed command is manually controlled amplitude When it exceeds the second amplitude threshold, that is At that time, stop the sway suppression and adjust the dynamic weighting factor. Set to 0, ;

[0084] When the speed command is manually controlled amplitude When the amplitude is greater than or equal to the first amplitude threshold and less than or equal to the second amplitude threshold, that is... hour, The value is based on linear interpolation and ranges from 0.0 to 1.0.

[0085] When the operator makes a slight movement, the sway suppression command has a high weight; when the operator makes a violent movement, the system prioritizes the operator's intention, and the weight of the sway suppression command is reduced or becomes zero. This ensures that the system completes the sway suppression action without interference or even without being perceived, achieving human-machine collaborative operation.

[0086] S302: Reduce sway acceleration Convert to anti-shaking speed And based on dynamic weighting factors Manually manipulate speed commands With sway speed The final speed command is obtained by performing command fusion. ;

[0087]

[0088]

[0089] S303: Final speed command based on vehicle status Perform amplitude limiting and change the final speed command. Transmitted to the execution module;

[0090] Vehicle status includes boom length and boom angle, and is related to the final speed command. Amplitude limiting is performed to ensure the final speed command. and sway acceleration The magnitude can be less than or equal to the maximum sway suppression speed and maximum sway suppression acceleration allowed by the system.

[0091] Based on the anti-rollover capability, the length and angle of the boom determine the limits of the vehicle's stability. The maximum allowable sway speed and maximum sway acceleration of the system ensure that the vehicle will not become unstable under any circumstances.

[0092] In this embodiment, the final speed command The amplitude limiting is implemented using a lookup table method. The core of this method is to establish a known, rigorously calculated and tested stability envelope. The steps for implementing the lookup table method are as follows:

[0093] A. Establish the maximum permissible lateral acceleration corresponding to this posture based on the input variables boom length L and the angle θ between the boom and the horizontal plane. and maximum permissible lateral speed A two-dimensional lookup table;

[0094] Through theoretical calculations (such as torque balance) and physical testing, the maximum safe dynamic parameters under different boom configurations are determined; a two-dimensional lookup table is obtained and stored in the controller; based on the input variables boom length L and the angle θ between the boom and the horizontal plane, the maximum permissible lateral acceleration corresponding to that posture is output. and maximum permissible lateral speed ;

[0095] The example lookup table structure is as follows; the values ​​are for illustrative purposes and need to be calibrated according to actual conditions:

[0096] When the boom length L is 10m and the angle θ between the boom and the horizontal plane is 75°, the maximum permissible lateral acceleration is... for Maximum permissible lateral speed for ;

[0097] When the boom length L is 10m and the angle θ between the boom and the horizontal plane is 45°, the maximum permissible lateral acceleration is... for Maximum permissible lateral speed for ;

[0098] When the boom length L is 20m and the angle θ between the boom and the horizontal plane is 75°, the maximum permissible lateral acceleration is... for Maximum permissible lateral speed for ;

[0099] When the boom length L is 20m and the angle θ between the boom and the horizontal plane is 45°, the maximum permissible lateral acceleration is... for Maximum permissible lateral speed for .

[0100] B. Read the current boom length from the boom sensor. The angle between the boom and the horizontal plane ,by( , Using ) as the index, retrieve the maximum permissible lateral acceleration under the current operating condition from a pre-stored two-dimensional lookup table. and maximum permissible lateral speed .

[0101] The maximum permissible lateral acceleration under the current operating conditions and maximum permissible lateral speed Set as the final speed command within the current cycle. A new threshold for limiting amplitude;

[0102] S4: Based on the received final speed command Generate the required motor torque command This signal is then converted into a motor drive signal to control the chassis motor to perform operations.

[0103] In this embodiment, the execution module includes a left travel motor controller and a right travel motor controller;

[0104] The execution module controls the execution steps as follows:

[0105] S401: Final speed command Decomposed into the target speed of the vehicle's moving wheels ;

[0106] In this embodiment, for a wheeled chassis, the final speed command is based on the vehicle kinematics model. Decomposed into the target speed of the vehicle's left wheel and the target speed of the right wheel .

[0107] Final speed command after fusion and limiting It is a vector, containing magnitude and direction, for the final velocity command. The kinematic decomposition is performed as follows:

[0108] To obtain the chassis sway angular acceleration required for sway reduction It can be represented as:

[0109]

[0110] in, To suppress swaying acceleration; It is the effective working length of the boom, which is the horizontal projection length of the boom.

[0111] Then, we measured the chassis sway angle acceleration. Integrate to obtain the chassis sway angular velocity required for sway reduction. The calculation formula is as follows: target speed Including revolver target speed and the target speed of the right wheel ,

[0112]

[0113]

[0114] Revolver target speed:

[0115] Right wheel target speed:

[0116] in, It is the chassis anti-sway angular velocity.

[0117] S402: Based on target tracking speed actual speed Generate the required motor torque command and convert it into a motor drive signal;

[0118] In this embodiment, each motor controller independently runs a PID control algorithm, receives the corresponding target speed, obtains the actual motor speed through an encoder, and uses a PI control algorithm to achieve the target speed. Including revolver target speed and the target speed of the right wheel Calculations make the actual speed Track target speed The required motor torque is obtained by receiving the motor torque command. The formula is as follows:

[0119]

[0120] in, For speed error, ; and These are pre-calibrated control parameters; The integral of velocity error is expressed as the integral result changes with time. change, This indicates that integration is being performed.

[0121] The system is based on the target speed of the left wheel. and the target speed of the right wheel Two independent, potentially numerically different, left-wheel torque commands are obtained. and right wheel torque command .

[0122] Under the precise control of the current loop, the left and right motors respectively output torque commands to the left wheel. and right wheel torque command Due to the left wheel torque command and right wheel torque command There are almost always differences (i.e.) Differential driving or braking forces are generated on the two drive wheels; the force difference forms a couple, driving the chassis to produce the lateral translation or rotational motion (yaw motion) required for sway suppression. This chassis motion is transmitted through the boom, applying an inertial force to the basket in the opposite direction of the sway, ultimately achieving active sway suppression.

[0123] In this embodiment, the motor torque command is converted into a motor drive signal PWM wave, which drives the left and right travel motors to generate corresponding torque through the motor driver. The motor current, speed and other parameters are monitored in real time to achieve closed-loop control.

[0124] In this invention, the driving force or braking force generated by the left and right travel motors is used to generate a sway-suppressing force that causes the chassis to move laterally or rotate. This force is transmitted to the basket through the boom to counteract the original swaying and achieve active sway suppression. In addition, the motor status data, including the actual speed and torque, is fed back to the decision control module to form a closed-loop control.

[0125] This invention directly controls a walking motor with extremely fast response speed. The control law based on the equivalent inverted pendulum model has a clear physical meaning, is simple to calculate, and can achieve real-time control. The chassis translational motion has a direct and linear effect on the suspended platform, avoiding the nonlinear coupling problem of the boom motion.

[0126] This invention achieves direct monitoring of the sway suppression target by directly installing an inertial measurement unit (IMU) on the suspended platform. The control target is the attitude stability of the suspended platform, rather than the stability of the chassis. Therefore, the system can intervene at the initial stage of swaying, detecting even a small angle of the suspended platform, eliminating risks in their nascent stage. Furthermore, it requires minimal modification to the vehicle's mechanical structure and is easy to implement.

[0127] This invention achieves full automation of the sway suppression process. The command fusion technology ensures that the system will not interfere with the operator's normal driving intentions during sway suppression, achieving imperceptible sway suppression. In addition, the operator can operate the system as if it were a normal stable vehicle, without having to change their habits.

[0128] A motor control system for suppressing swaying in aerial work platforms, applicable to the aforementioned motor control method for suppressing swaying in aerial work platforms, includes a data acquisition module, a decision control module, an instruction fusion module, and an execution module; wherein,

[0129] Data acquisition module: Used to acquire and obtain the human-operated speed commands from the joystick sensor. The data is transmitted to the instruction fusion module, which collects the raw data of the swaying state of the suspended platform and transmits the preprocessed data of the swaying state of the suspended platform to the decision control module;

[0130] Decision control module: Used to identify the swaying state of the suspended platform based on the swaying state data and generate sway suppression commands, including sway suppression acceleration. and sway speed ;

[0131] Command fusion module: Used to fuse the sway control command from the decision control module with the human control command from the joystick sensor to obtain the final speed command. and the final speed command The signal is transmitted to the execution module; and the final speed command is determined based on the vehicle status. Amplitude limiting is applied;

[0132] Human control commands include human control speed commands. ;

[0133] Execution module: Used to execute the received final speed command. Generate the required motor torque command This signal is then converted into a motor drive signal to control the chassis motor to perform operations.

[0134] The above are merely preferred embodiments of the present invention, but the scope of protection of the present invention is not limited thereto. Any equivalent substitutions or modifications made by those skilled in the art within the scope of the technology disclosed in the present invention, based on the technical solution and inventive concept of the present invention, should be covered within the scope of protection of the present invention.

Claims

1. A method of motor control for damping of a high aerial work platform, characterized in that, include: S1: Collect and acquire the human-operated speed command data from the joystick sensor, and preprocess the collected raw data of the basket's swaying state to obtain the basket's swaying state data; the basket's swaying state data includes the basket's three-axis angular velocity and three-axis acceleration; S2: Identify the swaying state of the suspended basket based on the obtained swaying state data and generate a sway suppression command; S3: The sway suppression command and the manually controlled speed command are fused to obtain the final speed command, and the final speed command is limited according to the vehicle status. S4: Generates the required motor torque command based on the received final speed command, and converts it into a motor drive signal to control the chassis motor to perform operations.

2. The motor control method according to claim 1, characterized in that, The S2 generates a sway suppression command, which includes the following steps: the sway suppression command includes a sway suppression acceleration; S201: The data on the swaying state of the suspended platform are fused and processed to calculate the angle data of the suspended platform relative to the horizontal plane; S202: Perform high-pass filtering on the acquired angle data and sway state data of the suspended platform to obtain the filtered sway angle and angular velocity, and calculate the real-time angular acceleration of the suspended platform. S203: The type of sway is determined by comparing the calculated real-time angular acceleration of the suspended platform with the angular acceleration safety threshold of the suspended platform; When the swaying of the suspended platform is determined to be dangerous, a safety response is triggered. If the swaying of the suspended platform is determined to be normal swaying, proceed to step S204; S204: The sway suppression acceleration in the sway suppression command is calculated based on the filtered sway angle and angular velocity of the suspended basket.

3. The motor control method according to claim 2, characterized in that: The S201 uses the quaternion method or complementary filtering algorithm to fuse the three-axis angular velocity and three-axis acceleration in the hoist sway state data, and after calculation, obtains the real-time roll angle and real-time pitch angle data of the hoist relative to the horizontal plane.

4. The motor control method according to claim 2, characterized in that: S204, based on the filtered swing angle and angular velocity of the basket, applies the PD control law to the constructed equivalent inverted pendulum dynamic model to obtain the sway-suppressing acceleration.

5. The motor control method according to claim 4, characterized in that: The aforementioned equivalent inverted pendulum dynamic model maps the chassis, boom, and basket of the aerial work platform vehicle into an equivalent inverted pendulum model. The basket is equivalent to a pendulum bob located at the top of the pendulum rod, the boom is equivalent to a massless rigid pendulum rod of length L, and the contact point between the chassis and the ground is regarded as the fulcrum of the pendulum.

6. The motor control method according to claim 1, characterized in that: In step S3, the sway suppression command from step S3 and the manual speed command from the joystick sensor are fused to obtain the final speed command. The process is as follows: S301: Calculate the dynamic weighting factor corresponding to the sway suppression acceleration and the manually controlled speed command; S302: Convert the sway-suppressing acceleration into sway-suppressing velocity, and fuse the manually manipulated speed command with the sway-suppressing velocity based on the dynamic weighting factor to obtain the final speed command.

7. The motor control method according to claim 6, characterized in that: In step S301, the dynamic weighting factor is calculated based on the amplitude of the manually controlled speed command according to the following principles: When the amplitude of the manually manipulated speed command is less than the first amplitude threshold, the dynamic weighting factor is set to 1; When the amplitude of the manually manipulated speed command exceeds the second amplitude threshold, the dynamic weighting factor is set to 0. When the amplitude of the manually manipulated speed command is greater than or equal to the first amplitude threshold and less than or equal to the second amplitude threshold, the magnitude of the dynamic weighting factor is based on linear interpolation and takes a value between 0.0 and 1.

0.

8. The motor control method according to claim 1, characterized in that: The final speed command is limited based on the vehicle's status. A. Establish a two-dimensional lookup table based on the input variables boom length and the angle between the boom and the horizontal plane to obtain the maximum permissible lateral acceleration and maximum permissible lateral velocity corresponding to the posture; B. Read the current boom length and the angle between the boom and the horizontal plane from the boom sensor. Using the current boom length and the angle between the boom and the horizontal plane as indexes, query the maximum permissible lateral acceleration and the maximum permissible lateral velocity under the current working condition from the pre-stored two-dimensional lookup table.

9. The motor control method according to claim 1, characterized in that: S4, as mentioned above, controls the chassis motor to perform operations. S401: Decompose the final speed command into the target speeds of the vehicle's moving wheels; The process includes the following steps: the target speed of the vehicle's moving wheels includes the target speed of the left wheel and the target speed of the right wheel; the chassis sway angular acceleration required for sway suppression is obtained based on the sway suppression acceleration and the horizontal projection length of the boom; the chassis sway angular acceleration is integrated to obtain the chassis sway angular velocity required for sway suppression; and the target speeds of the left and right wheels are calculated based on the final speed command and the chassis sway angular velocity. S402: Generates the required motor torque command based on the actual speed of the target speed and converts it into a motor drive signal; The speed error is calculated based on the target speed and the actual speed. A PI control algorithm is applied to the speed error to obtain the motor torque command. The motor torque command is then converted into a PWM wave motor drive signal, which drives the left and right travel motors through the motor driver.

10. A motor control system for suppressing swaying in aerial work platforms, applicable to the motor control method described in any one of claims 1 to 9, characterized in that: It includes a data acquisition module, a decision control module, an instruction fusion module, and an execution module; among which, The data acquisition module is used to acquire and transmit the human-operated speed command data from the joystick sensor to the command fusion module, and to acquire the raw data of the basket's swaying state and transmit the preprocessed data of the basket's swaying state to the decision control module. The decision control module is used to identify the swaying state of the suspended basket based on the swaying state data and generate sway suppression commands, which include sway suppression acceleration and sway suppression speed. The command fusion module is used to fuse the sway suppression command from the decision control module with the human control command from the joystick sensor to obtain the final speed command, and transmit the final speed command to the execution module; and to perform amplitude limiting processing on the final speed command according to the vehicle status; the human control command includes the human control speed command; The execution module is used to generate the required motor torque command based on the received final speed command, and convert it into a motor drive signal to control the chassis motor to perform operations.

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