A dynamic acceleration and deceleration constraint mobile robot motion control method

Abstract

The application belongs to the field of mobile robot motion control, and relates to a mobile robot motion control method with dynamic acceleration and deceleration constraints. The method comprises parameter initialization, acceleration and deceleration curve modeling, dynamic curve adjustment and control output constraint. The application introduces a stage model of acceleration and deceleration of in-place rotation control and walking control, dynamically adjusts the acceleration and deceleration curve in combination with external control signals, environment feedback and curvature change of a path, realizes smooth transition and intelligent adjustment of linear velocity and angular velocity of the mobile robot in the path execution process, and significantly improves the path tracking precision, control robustness and intelligence and safety level of the whole motion control system.

Description

Technical Field

[0001] This invention belongs to the field of mobile robot motion control and relates to a mobile robot motion control method with dynamic acceleration and deceleration constraints. Background Technology

[0002] In recent years, with the rapid development of artificial intelligence, industrial automation, and mobile communication technologies, advanced equipment, represented by intelligent mobile robots, has gradually moved from the laboratory to widespread practical applications. This type of intelligent equipment has demonstrated significant application value in various fields such as healthcare, education and training, service industries, warehousing and logistics, and industrial manufacturing, effectively reducing labor costs, improving production efficiency, and enhancing the quality of human life, thus possessing significant social and economic importance.

[0003] In practical engineering applications of mobile robots, the dynamic response performance of motion control algorithms directly determines the overall operating efficiency and stability of the system. In particular, the proper setting of acceleration parameters requires a delicate balance between device response speed and motion smoothness: excessive acceleration may cause severe impacts to the mechanical body, reducing equipment stability and posing safety hazards; conversely, excessively low acceleration fails to meet the rigid demands for operational efficiency in industrial scenarios. Furthermore, mobile robots inevitably encounter various working conditions during actual operation, such as the need for timely deceleration and avoidance when encountering obstacles, rapid stopping in emergencies, smooth deceleration during task pauses, and gradual acceleration upon task resumption.

[0004] In warehouse handling applications, mobile robots require smooth acceleration and deceleration control to ensure operational safety and accuracy. Due to the varying performance of motors in different robot models, their angular and linear velocity response capabilities differ when approaching the target location or station. If traditional methods are used to reduce the angular or linear velocity to extremely low values, some robots may fail to respond, causing them to stop and preventing task completion. Similarly, in angular or linear velocity control, abruptly dropping from high speed to extremely low speed or stopping abruptly not only affects positioning accuracy but may also adversely impact cargo stability and system lifespan.

[0005] Chinese Patent Publication No. CN117519205A discloses a method for accelerating and decelerating a mobile robot. This technical solution calculates the difference between the current linear velocity and the next linear velocity of the mobile robot, then uses this difference to correct the linear velocity and adaptively adjust the angular velocity at the next moment. By dynamically changing the output value of the response at the next moment based on the changes in the linear and angular velocities of the mobile robot, the system ensures stable movement of the robot and, as much as possible, maintains the robot's original trajectory, thus improving the safety performance and control system of the mobile robot. This method accelerates or decelerates the speed difference between the current and next moments, and corrects the linear and angular velocity values ​​of the mobile robot without changing the control radius. It alters the control variables for the tracking path, thus changing the target effect of path tracking.

[0006] Chinese patent CN119575974A discloses a method, apparatus, device, and storage medium for speed planning of mobile robots. This technical solution divides the movement process of a mobile robot from a starting point to an ending point into multiple stages, avoiding abrupt acceleration changes, effectively increasing the robot's lifespan and reducing the failure rate. Furthermore, by establishing a correspondence between displacement and velocity, subsequent speed control of the mobile robot's motion can be directly based on this correspondence without complex calculations, enabling even microcontrollers with average performance to achieve smooth and efficient acceleration and deceleration control. However, this method does not consider the smooth control of angular velocity when the stationary rotational speed is zero.

[0007] For the aforementioned complex working conditions, how to construct acceleration and deceleration curves with continuous and differentiable characteristics to ensure smooth transition of motion states and achieve shock-free and stable start-up has important engineering value for extending the service life of machinery and ensuring operational safety. Summary of the Invention

[0008] To address the above issues, this invention provides a mobile robot motion control method with dynamic acceleration and deceleration constraints. Within a certain distance from the target position, the robot automatically enters a slow-deceleration phase, maintaining a low and controllable speed to a smooth stop. This balances control precision and motor responsiveness, preventing loss of control or slippage due to excessive deceleration. Furthermore, unless in an emergency, the mobile robot avoids drastic acceleration and deceleration throughout its operation, ensuring cargo safety, equipment durability, and improved overall operational efficiency.

[0009] The technical solution adopted by the present invention to achieve the above objectives is: a motion control method for a mobile robot with dynamic acceleration and deceleration constraints, comprising the following steps: S1. Parameter initialization: Set the acceleration and deceleration parameters for stationary rotation control and walking control to provide a basic configuration for subsequent modeling; S2. Acceleration and deceleration curve modeling: Construct an acceleration and deceleration gradient curve model to describe the dynamic characteristics of the robot during velocity changes; S3. Dynamic Curve Adjustment: Based on external control signals or environmental feedback, the parameter values ​​in the curve model are adjusted in real time to achieve dynamic optimization of the acceleration and deceleration process. S4. Control Output Constraints: The adjusted acceleration / deceleration control values ​​are used as constraint inputs and provided to the path tracking module to ensure that the robot runs smoothly and accurately during path execution.

[0010] In step S1, the in-situ rotation control refers to the scenario where the mobile robot adjusts its orientation in place, including orientation calibration before starting, angle adjustment after the task is completed, and angle rotation operation in response to external commands. The control includes: a rotation acceleration phase, which gradually increases the angular velocity from a stationary state to avoid sudden changes in angular velocity that could cause instability in posture or a decrease in control accuracy; a rotation constant speed phase, which maintains a constant angular velocity during the rotation process to achieve high-speed and stable angle adjustment; and a rotation deceleration phase, which gradually decreases the angular velocity as it approaches the target angular velocity to prevent overshoot and improve angle control accuracy.

[0011] The parameter settings for acceleration and deceleration in the in-situ rotation control include the setting of the following angular velocity control parameters: (1) Set the maximum angular velocity , in rad / s, is used to limit the maximum angular velocity of a mobile robot during rotation; (2) Set angular acceleration Unit: rad / s 2 It is used to control the acceleration process of angular velocity from zero to its maximum value; (3) Set angular deceleration Unit: rad / s 2 Used for smooth deceleration when approaching the target speed; (4) Set the minimum effective angular velocity The unit is rad / s, to prevent the actuator from failing to respond due to excessively low angular velocity at low speeds. (5) Set the stop judgment threshold The unit is rad, meaning that the mission rotation is complete when the difference between the orientation and the target orientation is less than this value. (6) Set the robot's control cycle to t, in seconds.

[0012] In step S2, constructing the acceleration / deceleration gradient curve model includes a rotational acceleration / deceleration gradient curve model to describe the dynamic characteristics of the robot's angular velocity during rotation. The rotational acceleration / deceleration gradient curve model includes: When entering the control flow for the first time or when the angular velocity is reset by an external setting, initialize the angular velocity from the previous moment. And reset the deceleration state to false; Based on the robot's current orientation Orientation towards the target The angle difference between , ;like This means the vehicle needs to rotate to the left in place; conversely, if... This indicates that the vehicle needs to rotate to the right in place; the direction of rotation follows the right-hand rule. When the angular velocity has reached the set threshold, the rotation task is completed, the output angular velocity is zero, and the control ends. The acceleration phase of a mobile robot is as follows: ; Utilizing the above-mentioned acceleration Real-time calculation of the angle value required for deceleration during rotation. When the remaining angle difference At that time, the vehicle enters deceleration and braking process, that is... The aforementioned deceleration and braking process, once the robot enters the deceleration state and the deceleration state is set to true, the robot will continue to decelerate until the minimum effective angular velocity is reduced. Then, when the remaining angle meets the stop judgment threshold, the rotation action is completed.

[0013] In step S1, the walking control refers to the speed control used by the robot in motion during path tracking, handling operations, etc. The control includes: acceleration phase, that is, gradually increasing the linear speed from the starting state to allow the robot to smoothly enter the path tracking state; constant speed phase, maintaining a stable linear speed in the middle of the path or on a straight path to achieve efficient walking behavior; deceleration phase, that is, gradually reducing the linear speed when approaching the target position or when it is necessary to stop the operation to ensure that the vehicle stops smoothly, improve positioning accuracy and ensure the safety of the goods.

[0014] The acceleration and deceleration parameter settings for the walking control include the setting of the following speed control parameters: (1) Set the maximum linear velocity V1, in m / s, to limit the robot's maximum travel speed during the movement process; (2) Set the linear acceleration to A1, in m / s². 2 It is used to control the acceleration process of a robot from a stationary state to its maximum speed, ensuring that the acceleration process is smooth and controlled; (3) Set the linear deceleration to A2, in m / s². 2It is used to control the robot to decelerate to a stop when it approaches the target point, so as to avoid exceeding the target position due to insufficient braking distance; (4) Set the minimum linear speed to V2, in m / s, to prevent the driver from not responding or the vehicle from moving due to the low linear speed during low-speed driving, and to ensure that effective movement can still be generated during fine control. (5) Set the low-speed switching distance threshold to D1, in meters, to determine whether the distance between the robot and the target point has entered the low-speed driving area. When the remaining distance is less than D1, the mobile robot will maintain the minimum linear speed V2. (6) Set the parking distance to D 2， The unit m is used to determine whether the vehicle has reached the mission point; (7) Set the minimum turning speed to V3, in m / s, to keep the vehicle in a controllable state when the robot is turning or moving at low speed, and to avoid dead zones or slipping in place.

[0015] In step S2, constructing the acceleration / deceleration gradient curve model includes a walking acceleration / deceleration gradient curve model to describe the dynamic characteristics of the robot's linear velocity during walking. The walking acceleration / deceleration gradient curve model includes: Upon first entering the control flow or when the angular velocity is reset by an external setting, the linear velocity V from the previous moment is initialized. P =0, and reset the deceleration state to false; if the robot enters the condition that meets the condition to reach the target point, the walking task is completed; The acceleration phase of a mobile robot is as follows: Using the accelerated V as described above, the distance that needs to be decelerated during walking can be calculated in real time. When the distance between the robot and the target point At this time, the vehicle enters deceleration and braking process, that is: ; When the robot is in the acceleration or constant-speed phase, if it continues to maintain a high linear velocity when the path contains curves with significant curvature, the path tracking accuracy will decrease. Therefore, the robot's output linear velocity is constrained based on the real-time curvature value of the path. Assuming the calculated curvature velocity is... The final output control speed is: ; The curvature velocity calculation method includes: The path to be tracked is segmented offline according to a preset map resolution m to obtain a path point sequence; Obtain the index of the nearest path point corresponding to the robot's current pose, and search forward along the path from that index point. Each path point is searched backwards along the path. There are 1 path points, where K1 and K2 are preset constant values, m is the map resolution, and the path points in front and behind together constitute the path sampling set. The slope angle θ between adjacent path points in the path sampling set is calculated using the following formula: ,in, and These are the coordinates of two adjacent path points; Accumulate the slope angles of all adjacent points in the path sampling set and accumulate the value. Set to not exceed π; Accumulated value Substituting the values ​​into a high-speed function for calculating the curvature coefficient yields the curvature coefficient. A smaller value indicates a flatter path; a value of zero indicates that the path is currently tracing a straight line. The input is defined as... ,but ,like At that time, it was further adjusted to: Then the curvature velocity at the current moment is: .

[0016] The method of determining whether the vehicle has reached the task point addresses the issue of mobile robots failing to accurately stop at the target point due to inertial slippage or navigation errors, rather than directly relying on the robot's end-effector pose. Instead of using it as a parking determination point, a parking control extension point is introduced. It is obtained by extending the target pose along its orientation direction by a distance D2. The method for calculating the reference control point N is as follows: Where: D2 > 0 indicates early stopping, the robot will stop in front of the target point; D2 = 0 indicates stopping strictly at the target point; D2 < 0 indicates the robot will stop only after passing the target. A task reference line segment is constructed between the target point M and the extension point N. A normal determination line perpendicular to the direction of this line segment is constructed at point N as the boundary for whether the task point has been reached: when the robot's real-time position and its position L meters in front of the target point are on one side of the normal determination line, it means the robot has not reached the target point and needs to continue walking; when they are on both sides of the normal determination line, it means the robot has reached the target point and the walking task is completed. .

[0017] In step S3, the external control signal or environmental feedback signal includes one or more of the following: When the vehicle encounters an obstacle in front of it while it is moving, and it needs to reduce its speed, the vehicle acceleration / deceleration module will automatically reduce the maximum linear speed parameter. When an external system issues a pause command, the deceleration parameter will be increased and the target point position will be advanced, thus enabling the mobile robot to decelerate to zero more quickly. When the obstacle is abnormal or the paused state is reached, the maximum linear velocity is restored to the value in the preset configuration parameters; When an emergency occurs, such as the emergency stop button being pressed, the anti-collision strip being triggered, or the obstacle avoidance radar detecting a nearby obstacle, the angular velocity and / or linear velocity of the vehicle body immediately drop to zero. After the aforementioned danger is eliminated, the vehicle gradually accelerates from zero to its maximum speed with a preset acceleration.

[0018] In step S4, the path tracking module includes line tracking control and nonlinear control.

[0019] Building upon the aforementioned acceleration / deceleration curve model, an adaptive speed control mechanism based on path prediction or machine learning can be further introduced. Specifically, by utilizing the robot's current position and the local curvature of the predetermined path, obstacle distribution, and historical motion data, deep reinforcement learning or model predictive control methods can be employed to dynamically generate a better acceleration / deceleration control strategy. This approach, while maintaining real-time response and safety, further enhances the ability to balance path execution efficiency and energy consumption control in complex dynamic environments.

[0020] This invention introduces a phased acceleration and deceleration model combining in-situ rotation control and walking control. By integrating external control signals, environmental feedback, and changes in path curvature, it dynamically adjusts the acceleration and deceleration curves, achieving smooth transitions and intelligent adjustment of linear and angular velocities for the mobile robot during path execution. The system can flexibly adjust the acceleration and deceleration rhythm based on the straight or curved characteristics of the path, improving operational stability and control accuracy in turning areas. Simultaneously, it can quickly respond and safely decelerate upon detecting obstacles or receiving external commands such as emergency stops, significantly enhancing safety and environmental adaptability during operation. Furthermore, by introducing a delayed stopping determination strategy, this invention no longer relies solely on the distance between the robot's pose and the navigation target point's pose when determining whether the robot has reached the task point. Instead, it constructs a control area and normal boundary line a certain distance ahead of the target point to accurately determine the arrival status, effectively solving the stopping deviation problem caused by inertial slippage or navigation errors, further improving positioning accuracy and task completion reliability. In summary, this invention significantly improves path tracking accuracy, control robustness, and the intelligence and safety level of the entire motion control system. Attached Figure Description

[0021] Figure 1 This is a diagram of the acceleration / deceleration constraint module of the present invention.

[0022] Figure 2 This is a schematic diagram for determining whether the target point has been reached. Detailed Implementation

[0023] The present patent will be further described below with reference to the accompanying drawings and specific embodiments: Example

[0024] like Figure 1 The method for motion control of a mobile robot with dynamic acceleration and deceleration constraints, as shown, includes the following steps: S1. Parameter initialization: Set the acceleration and deceleration parameters for stationary rotation control and walking control to provide a basic configuration for subsequent modeling; S2. Acceleration and deceleration curve modeling: Construct an acceleration and deceleration gradient curve model to describe the dynamic characteristics of the robot during velocity changes; S3. Dynamic Curve Adjustment: Based on external control signals or environmental feedback, the parameter values ​​in the curve model are adjusted in real time to achieve dynamic optimization of the acceleration and deceleration process. S4. Control Output Constraints: The adjusted acceleration / deceleration control values ​​are used as constraint inputs and provided to the path tracking module to ensure that the robot runs smoothly and accurately during path execution.

[0025] In step S1, the in-situ rotation control refers to the scenario where the mobile robot adjusts its orientation in place, including orientation calibration before starting, angle adjustment after the task is completed, and angle rotation operation in response to external commands. The control includes: a rotation acceleration phase, which gradually increases the angular velocity from a stationary state to avoid sudden changes in angular velocity that could cause instability in posture or a decrease in control accuracy; a rotation constant speed phase, which maintains a constant angular velocity during the rotation process to achieve high-speed and stable angle adjustment; and a rotation deceleration phase, which gradually decreases the angular velocity as it approaches the target angular velocity to prevent overshoot and improve angle control accuracy.

[0026] The parameter settings for acceleration and deceleration in the in-situ rotation control include the setting of the following angular velocity control parameters: (1) Set the maximum angular velocity , in rad / s, is used to limit the maximum angular velocity of a mobile robot during rotation; (2) Set angular acceleration Unit: rad / s 2 It is used to control the acceleration process of angular velocity from zero to its maximum value; (3) Set angular deceleration Unit: rad / s 2 Used for smooth deceleration when approaching the target speed; (4) Set the minimum effective angular velocity The unit is rad / s, to prevent the actuator from failing to respond due to excessively low angular velocity at low speeds. (5) Set the stop judgment threshold The unit is rad, meaning that the mission rotation is complete when the difference between the orientation and the target orientation is less than this value. (6) Set the robot's control cycle to t, in seconds.

[0027] In step S2, constructing the acceleration / deceleration gradient curve model includes a rotational acceleration / deceleration gradient curve model to describe the dynamic characteristics of the robot's angular velocity during rotation. The rotational acceleration / deceleration gradient curve model includes: When entering the control flow for the first time or when the angular velocity is reset by an external setting, initialize the angular velocity from the previous moment. And reset the deceleration state to false; Based on the robot's current orientation Orientation towards the target The angle difference between , ;like This means the vehicle needs to rotate to the left in place; conversely, if... This indicates that the vehicle needs to rotate to the right in place; the direction of rotation follows the right-hand rule. When the angular velocity has reached the set threshold, the rotation task is completed, the output angular velocity is zero, and the control ends. The acceleration phase of a mobile robot is as follows: ; Utilizing the above-mentioned acceleration Real-time calculation of the angle value required for deceleration during rotation. When the remaining angle difference At that time, the vehicle enters deceleration and braking process, that is... The aforementioned deceleration and braking process, once the robot enters the deceleration state and the deceleration state is set to true, the robot will continue to decelerate until the minimum effective angular velocity is reduced. Then, when the remaining angle meets the stop judgment threshold, the rotation action is completed.

[0028] In step S1, the walking control refers to the speed control used by the robot in motion during path tracking, handling operations, etc. The control includes: acceleration phase, that is, gradually increasing the linear speed from the starting state to allow the robot to smoothly enter the path tracking state; constant speed phase, maintaining a stable linear speed in the middle of the path or on a straight path to achieve efficient walking behavior; deceleration phase, that is, gradually reducing the linear speed when approaching the target position or when it is necessary to stop the operation to ensure that the vehicle stops smoothly, improve positioning accuracy and ensure the safety of the goods.

[0029] The acceleration and deceleration parameter settings for the walking control include the setting of the following speed control parameters: (1) Set the maximum linear velocity V1, in m / s, to limit the robot's maximum travel speed during the movement process; (2) Set the linear acceleration to A1, in m / s². 2It is used to control the acceleration process of a robot from a stationary state to its maximum speed, ensuring that the acceleration process is smooth and controlled; (3) Set the linear deceleration to A2, in m / s². 2 It is used to control the robot to decelerate to a stop when it approaches the target point, so as to avoid exceeding the target position due to insufficient braking distance; (4) Set the minimum linear speed to V2, in m / s, to prevent the driver from not responding or the vehicle from moving due to the low linear speed during low-speed driving, and to ensure that effective movement can still be generated during fine control. (5) Set the low-speed switching distance threshold to D1, in meters, to determine whether the distance between the robot and the target point has entered the low-speed driving area. When the remaining distance is less than D1, the mobile robot will maintain the minimum linear speed V2. (6) Set the parking distance to D 2， The unit m is used to determine whether the vehicle has reached the mission point; (7) Set the minimum turning speed to V3, in m / s, to keep the vehicle in a controllable state when the robot is turning or moving at low speed, and to avoid dead zones or slipping in place.

[0030] In step S2, constructing the acceleration / deceleration gradient curve model includes a walking acceleration / deceleration gradient curve model to describe the dynamic characteristics of the robot's linear velocity during walking. The walking acceleration / deceleration gradient curve model includes: Upon first entering the control flow or when the angular velocity is reset by an external setting, the linear velocity V from the previous moment is initialized. P =0, and reset the deceleration state to false; if the robot enters the condition that meets the condition to reach the target point, the walking task is completed; The acceleration phase of a mobile robot is as follows: Using the accelerated V as described above, the distance that needs to be decelerated during walking can be calculated in real time. When the distance between the robot and the target point At this time, the vehicle enters deceleration and braking process, that is: ; When the robot is in the acceleration or constant-speed phase, if it continues to maintain a high linear velocity when the path contains curves with significant curvature, the path tracking accuracy will decrease. Therefore, the robot's output linear velocity is constrained based on the real-time curvature value of the path. Assuming the calculated curvature velocity is... The final output control speed is: ; The curvature velocity calculation method includes: The path to be tracked is segmented offline according to a preset map resolution m to obtain a path point sequence; Obtain the index of the nearest path point corresponding to the robot's current pose, and search forward along the path from that index point. Each path point is searched backwards along the path. There are 1 path points, where K1 and K2 are preset constant values, m is the map resolution, and the path points in front and behind together constitute the path sampling set. The slope angle θ between adjacent path points in the path sampling set is calculated using the following formula: ,in, and These are the coordinates of two adjacent path points; Accumulate the slope angles of all adjacent points in the path sampling set and accumulate the value. Set to not exceed π; Accumulated value Substituting the values ​​into a high-speed function for calculating the curvature coefficient yields the curvature coefficient. A smaller value indicates a flatter path; a value of zero indicates that the path is currently tracing a straight line. The input is defined as... ,but ,like At that time, it was further adjusted to: Then the curvature velocity at the current moment is: .

[0031] The method of determining whether the vehicle has reached the task point addresses the issue of mobile robots failing to accurately stop at the target point due to inertial slippage or navigation errors, rather than directly relying on the robot's end-effector pose. Instead of using it as a parking determination point, a parking control extension point is introduced. It is obtained by extending the target pose along its orientation direction by a distance D2. The method for calculating the reference control point N is as follows: Where: D2 > 0 indicates that the robot will stop in advance, and will stop in front of the target point; D2 = 0 indicates that the robot will stop strictly at the target point; D2 < 0 indicates that the robot will stop only after it has passed the target. like Figure 2 As shown, a task reference line segment is constructed between the target point M and the extension point N. A normal direction determination line perpendicular to this line segment is constructed at point N, serving as the boundary for determining whether the task point has been reached: when the robot's real-time position and its position L meters ahead of the target point are on one side of the normal direction determination line, it indicates that the robot has not reached the target point and needs to continue moving; when they are on both sides of the normal direction determination line, it indicates that the robot has reached the target point, and the moving task is completed. .

[0032] In step S3, the external control signal or environmental feedback signal includes one or more of the following: When the vehicle encounters an obstacle in front of it while it is moving, and it needs to reduce its speed, the vehicle acceleration / deceleration module will automatically reduce the maximum linear speed parameter. When an external system issues a pause command, the deceleration parameter will be increased and the target point position will be advanced, thus enabling the mobile robot to decelerate to zero more quickly. When the obstacle is abnormal or the paused state is reached, the maximum linear velocity is restored to the value in the preset configuration parameters; When an emergency occurs, such as the emergency stop button being pressed, the anti-collision strip being triggered, or the obstacle avoidance radar detecting a nearby obstacle, the angular velocity and / or linear velocity of the vehicle body immediately drop to zero. After the aforementioned danger is eliminated, the vehicle gradually accelerates from zero to its maximum speed with a preset acceleration.

[0033] In step S4, the path tracking module includes line tracking control and nonlinear control.

Claims

1. A method for motion control of a mobile robot with dynamic acceleration and deceleration constraints, characterized in that: Includes the following steps: S1. Parameter initialization: Set the acceleration and deceleration parameters for stationary rotation control and walking control to provide a basic configuration for subsequent modeling; The acceleration and deceleration parameter settings for the walking control include the setting of the following speed control parameters: (1) Set the maximum linear velocity V1, in m / s, to limit the robot's maximum travel speed during the movement process; (2) Set the linear acceleration to A1, in m / s². 2 It is used to control the acceleration process of a robot from a stationary state to its maximum speed, ensuring that the acceleration process is smooth and controlled; (3) Set the linear deceleration to A2, in m / s². 2 It is used to control the robot to decelerate to a stop when it approaches the target point, so as to avoid exceeding the target position due to insufficient braking distance; (4) Set the minimum linear speed to V2, in m / s, to prevent the driver from not responding or the vehicle from moving due to the low linear speed during low-speed driving, and to ensure that effective movement can still be generated during fine control. (5) Set the low-speed switching distance threshold to D1, in meters, to determine whether the distance between the robot and the target point has entered the low-speed driving area. When the remaining distance is less than D1, the mobile robot will maintain the minimum linear speed V2. (6) Set the parking distance to D 2， The unit m is used to determine whether the vehicle has reached the task point. This determination addresses the problem of mobile robots failing to accurately stop at the target point due to inertial slippage or navigation errors, rather than directly using the robot's end-effector pose. Instead of using it as a parking determination point, a parking control extension point is introduced. It is obtained by extending the target pose along its orientation direction by a distance D2. The method for calculating the reference control point N is as follows: Where: D2 > 0 indicates early stopping, the robot will stop in front of the target point; D2 = 0 indicates stopping strictly at the target point; D2 < 0 indicates the robot will stop only after passing the target. A task reference line segment is constructed between the target point M and the extension point N. A normal determination line perpendicular to the direction of this line segment is constructed at point N as the boundary for whether the task point has been reached: when the robot's real-time position and its position L meters in front of the target point are on one side of the normal determination line, it means the robot has not reached the target point and needs to continue walking; when they are on both sides of the normal determination line, it means the robot has reached the target point and the walking task is completed. ; (7) Set the minimum turning speed to V3, in m / s, to keep the vehicle in a controllable state when the robot is turning or moving at low speed, and to avoid dead zones or slipping in place. S2. Acceleration / Deceleration Curve Modeling: Constructing an acceleration / deceleration gradient curve model to describe the dynamic characteristics of the robot during velocity changes; the construction of the acceleration / deceleration gradient curve model includes a walking acceleration / deceleration gradient curve model to describe the dynamic characteristics of the robot's linear velocity during walking, the walking acceleration / deceleration gradient curve model including: Upon first entering the control flow or when the angular velocity is reset by an external setting, the linear velocity V from the previous moment is initialized. P =0, and reset the deceleration state to false; if the robot enters the condition that meets the condition to reach the target point, the walking task is completed; The acceleration phase of a mobile robot is as follows: Using the accelerated V as described above, the distance that needs to be decelerated during walking can be calculated in real time. When the distance between the robot and the target point At this time, the vehicle enters deceleration and braking process, that is: ; When the robot is in the acceleration or constant-speed phase, if it continues to maintain a high linear velocity when the path contains curves with significant curvature, the path tracking accuracy will decrease. Therefore, the robot's output linear velocity is constrained based on the real-time curvature value of the path. Assuming the calculated curvature velocity is... The final output control speed is: ; The curvature velocity calculation method includes: The path to be tracked is segmented offline according to a preset map resolution m to obtain a path point sequence; Obtain the index of the nearest path point corresponding to the robot's current pose, and search forward along the path from that index point. Each path point is searched backwards along the path. There are 1 path points, where K1 and K2 are preset constant values, m is the map resolution, and the path points in front and behind together constitute the path sampling set. The slope angle θ between adjacent path points in the path sampling set is calculated using the following formula: ,in, and These are the coordinates of two adjacent path points; Accumulate the slope angles of all adjacent points in the path sampling set and accumulate the value. Set to not exceed π; Accumulated value Substituting the values ​​into a high-speed function for calculating the curvature coefficient yields the curvature coefficient. A smaller value indicates a flatter path; a value of zero indicates that the path is currently tracing a straight line. The input is defined as... ,but ,like At that time, it was further adjusted to: Then the curvature velocity at the current moment is: ; S3. Dynamic Curve Adjustment: Based on external control signals or environmental feedback, the parameter values ​​in the curve model are adjusted in real time to achieve dynamic optimization of the acceleration and deceleration process. S4. Control Output Constraints: The adjusted acceleration / deceleration control values ​​are used as constraint inputs and provided to the path tracking module to ensure that the robot runs smoothly and accurately during path execution.

2. The method for motion control of a mobile robot with dynamic acceleration and deceleration constraints according to claim 1, characterized in that: In step S1, the in-situ rotation control refers to the scenario where the mobile robot adjusts its orientation in place, including orientation calibration before starting, angle adjustment after the task is completed, and angle rotation operation in response to external commands. Its control includes: the rotational acceleration stage, which is to gradually increase the angular velocity from a stationary state to avoid sudden changes in angular velocity that could cause instability in posture or a decrease in control accuracy; The constant rotation speed stage involves maintaining a constant angular velocity during the rotation process to achieve high-speed and stable angle adjustment; the deceleration stage involves gradually reducing the angular velocity as the target angular velocity approaches to prevent overshoot and improve angle control accuracy.

3. A method for motion control of a mobile robot with dynamic acceleration and deceleration constraints according to claim 1 or 2, characterized in that: The parameter settings for acceleration and deceleration in the in-situ rotation control include the setting of the following angular velocity control parameters: (1) Set the maximum angular velocity , in rad / s, is used to limit the maximum angular velocity of a mobile robot during rotation; (2) Set angular acceleration Unit: rad / s 2 It is used to control the acceleration process of angular velocity from zero to its maximum value; (3) Set angular deceleration Unit: rad / s 2 Used for smooth deceleration when approaching the target speed; (4) Set the minimum effective angular velocity The unit is rad / s, to prevent the actuator from failing to respond due to excessively low angular velocity at low speeds. (5) Set the stop judgment threshold The unit is rad. When the difference between the orientation and the target orientation is less than this value, the mission rotation is complete. (6) Set the robot's control cycle to t, in seconds.

4. A method for motion control of a mobile robot with dynamic acceleration and deceleration constraints according to claim 1 or 2, characterized in that: In step S2, constructing the acceleration / deceleration gradient curve model includes a rotational acceleration / deceleration gradient curve model to describe the dynamic characteristics of the robot's angular velocity during rotation. The rotational acceleration / deceleration gradient curve model includes: When entering the control flow for the first time or when the angular velocity is reset by an external setting, initialize the angular velocity from the previous moment. And reset the deceleration state to false; Based on the robot's current orientation Orientation towards the target The angle difference between , ;like This means the vehicle needs to rotate to the left in place; conversely, if... This indicates that the vehicle needs to rotate to the right in place; the direction of rotation follows the right-hand rule. When the angular velocity has reached the set threshold, the rotation task is completed, the output angular velocity is zero, and the control ends. The acceleration phase of a mobile robot is as follows: ; Utilizing the above-mentioned acceleration Real-time calculation of the angle value required for deceleration during rotation. When the remaining angle difference At that time, the vehicle enters deceleration and braking process, that is... The aforementioned deceleration and braking process, once the robot enters the deceleration state and the deceleration state is set to true, the robot will continue to decelerate until the minimum effective angular velocity is reduced. Then, when the remaining angle meets the stop judgment threshold, the rotation action is completed.

5. The motion control method for a mobile robot with dynamic acceleration and deceleration constraints according to claim 1, characterized in that: In step S1, the walking control refers to the speed control used by the robot in motion during path tracking, handling operations, etc. The control includes: acceleration phase, that is, gradually increasing the linear speed from the starting state to allow the robot to smoothly enter the path tracking state; constant speed phase, maintaining a stable linear speed in the middle of the path or on a straight path to achieve efficient walking behavior; deceleration phase, that is, gradually reducing the linear speed when approaching the target position or when it is necessary to stop the operation to ensure that the vehicle stops smoothly, improve positioning accuracy and ensure the safety of the goods.

6. The method for motion control of a mobile robot with dynamic acceleration and deceleration constraints according to claim 1, characterized in that: In step S3, the external control signal or environmental feedback signal includes one or more of the following: When the vehicle encounters an obstacle in front of it while it is moving, and it needs to reduce its speed, the vehicle acceleration / deceleration module will automatically reduce the maximum linear speed parameter. When an external system issues a pause command, the deceleration parameter will be increased and the target point position will be advanced, thus enabling the mobile robot to decelerate to zero more quickly. When the obstacle is abnormal or the paused state is reached, the maximum linear velocity is restored to the value in the preset configuration parameters; When an emergency occurs, such as the emergency stop button being pressed, the anti-collision strip being triggered, or the obstacle avoidance radar detecting a nearby obstacle, the angular velocity and / or linear velocity of the vehicle body immediately drop to zero. After the aforementioned danger is eliminated, the vehicle gradually accelerates from zero to its maximum speed with a preset acceleration.

7. The method for motion control of a mobile robot with dynamic acceleration and deceleration constraints according to claim 1, characterized in that: In step S4, the path tracking module includes line tracking control and nonlinear control.

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