Waist-rotatable multi-axis linkage service robot and control method thereof

Abstract

The application discloses a waist-rotatable multi-axis linkage service robot and a control method thereof, and relates to the technical field of mobile service robots. The robot comprises a mobile chassis, a waist rotation joint, an upper body interaction unit and a controller. When the robot is charging, the waist rotation joint can drive the upper body interaction unit to be adjusted to an angle directly opposite a user, and the chassis is pre-turned to optimize the orientation, so that the human-machine interaction can be normally carried out, the service interruption caused by charging is avoided, the waist rotation process is divided into multiple control periods, the displacement increment is calculated and superimposed in real time, the mass center offset of the whole machine caused by the rotation of the upper body is offset, the chassis shaking and overturning problems are avoided, and the charging docking process is stable and safe. In addition, the charging interface is provided with a deviation detection sensor, the position and angle deviation are dynamically identified in combination with a displacement correction module, the pose error is quickly converged through closed-loop correction, and the one-time docking precision and success rate of the charging interface are effectively improved.

Description

Technical Field

[0001] This invention relates to the field of mobile service robot technology, specifically to a multi-axis linkage service robot with a rotatable waist and its control method. Background Technology

[0002] With the continuous expansion of service robot application scenarios, mobile robots with autonomous charging capabilities have become an industry necessity. In common autonomous charging solutions, robots often use a wired charging interface at the rear, connecting to a charging station by reversing or rotating in place. During this process, the robot's upper body typically houses human-computer interaction units such as displays, cameras, and microphones, whose orientation often rotates with the chassis. This results in the interface facing away from the user during charging, severely disrupting service continuity and user experience, particularly prominent in scenarios such as shopping malls, exhibition halls, and elderly care facilities.

[0003] To maintain the interaction orientation during charging, some solutions attempt to add a waist rotation joint above the chassis, allowing the upper body to rotate independently. However, this waist rotation significantly alters the overall center of gravity, especially when the robot is simultaneously performing docking and feeding movements. This shift in the center of gravity can easily lead to chassis wobbling, drive wheel slippage, or even robot tipping over, affecting docking accuracy and safety. Existing solutions mostly involve passive counterweights or static adjustments after rotation, which cannot compensate for changes in the center of gravity in real time and continuously during waist rotation. They also struggle to coordinate and synchronize with the charging and docking movements, resulting in low docking efficiency and a low success rate.

[0004] Therefore, how to ensure that service robots maintain the upper body interaction unit facing the user during the entire autonomous charging process, effectively suppress the center of gravity disturbance caused by waist rotation, and organically integrate center of gravity compensation, docking feed and interface deviation correction into multi-axis linkage control is a technical problem that urgently needs to be solved in this field. Summary of the Invention

[0005] To address the shortcomings of existing technologies, this invention provides a multi-axis linkage service robot with a rotatable waist and its control method, solving the problems mentioned in the background section.

[0006] To achieve the above objectives, the present invention provides the following technical solution: a multi-axis linkage service robot with a rotatable waist, comprising: The mobile chassis has a wired charging interface at the rear for docking with a charging pile; a deviation detection sensor is installed at the wired charging interface of the mobile chassis to detect the lateral position deviation and angular deviation of the wired charging interface relative to the charging pile electrode. A waist rotation joint is located above the movable chassis and rotates about a vertical axis; The upper body interaction unit is located above the waist rotation joint and is equipped with sensors for sensing the environment and the user. The controller, installed inside the mobile chassis, includes: The waist drive module, when the controller receives a charging command, is used to send a rotation command to the waist rotation joint, driving the upper body interaction unit to rotate from the initial angle to the target angle, so that the orientation of the upper body interaction unit changes from the initial direction to the user-facing direction; The center of gravity compensation module is used to calculate the offset of the whole machine's center of gravity caused by the rotation of the upper body interaction unit based on the current waist rotation angle of the waist rotation joint, and to generate a compensation displacement increment opposite to the offset of the whole machine's center of gravity and superimpose it on the moving chassis. The chassis pre-adjustment module is used to determine the target orientation angle of the mobile chassis based on the pre-detected user orientation angle, and to control the mobile chassis to rotate to the target orientation angle.

[0007] The chassis docking module is used to output motion commands to the mobile chassis during the rotation of the waist rotation joint, and control the mobile chassis to perform docking feed motion toward the charging pile; The displacement correction module calculates the correction displacement increment based on the lateral position deviation and angular deviation, and then adds the correction displacement increment to the motion command of the moving chassis.

[0008] As a further aspect of the present invention, the formula for calculating the target orientation angle is: ; where θ M Let θ be the target orientation angle. Y Let h be the user's orientation angle, h be the target angle, and the rotation range of the waist rotation joint should not be less than h.

[0009] As a further aspect of the present invention, when the waist drive module receives a rotation command, and before the rotation command is executed, the chassis pre-adjustment module controls the mobile chassis to rotate to the target orientation angle first.

[0010] As a further aspect of the present invention, the compensation displacement is calculated as follows: Obtain the pre-calibrated mass m of the upper body interaction unit. u The total mass M of the machine, and the position vector (dx, dy) of the center of mass of the upper body interaction unit relative to the waist rotation center in the chassis coordinate system; The real-time angle that the upper body interaction unit has rotated from the initial angle is obtained and set as the current waist rotation angle. ; pass: , Calculate the compensation displacement u in the X-axis direction. xCompensation displacement u in the Y-axis direction y ; In the formula, ΔX and ΔY represent the offset of the machine's center of gravity in the X-axis and Y-axis directions, respectively. The direction of the center of gravity offset is opposite to the direction of the compensation displacement, i.e. , .

[0011] As a further aspect of the present invention, the chassis coordinate system is a three-dimensional coordinate system established with the geometric center of the mobile chassis omnidirectional wheel assembly as the origin; the X-axis is the axis along the longitudinal direction of the chassis, and the Y-axis is the axis along the transverse direction of the chassis; the positive direction of the X-axis points to the forward direction of the chassis, and the positive direction of the Y-axis points to the side of the chassis.

[0012] As a further aspect of the present invention, the motion command generation method is as follows: the total rotation time T of the waist rotation joint is discretized into N control cycles, the required compensation displacement increment is calculated in each control cycle, and the compensation displacement increment is superimposed with the docking feed displacement increment to generate the motion command of the mobile chassis in the control cycle.

[0013] As a further aspect of the present invention, the motion command is specifically generated in the following manner: The controller sends corresponding position commands to the lumbar rotation joint, which are to bring the lumbar rotation joint to a predetermined intermediate angle. ,in: , i = 1, 2, ... N, where i is the index of the control cycle number and N is the number of control cycles; Within control period i, the compensation displacements in the X-axis and Y-axis directions are denoted as u, respectively. x，i and u y，i ; Calculate the compensation displacement in the X-axis and Y-axis directions of control cycle i, and calculate the difference between the compensation displacement in the X-axis and Y-axis directions of the control cycle i-1 that is adjacent to control cycle i, to obtain the compensation displacement increment that needs to be executed in control cycle i. The docking feed displacement increment is determined by the preset docking speed v. d and the duration of the control cycle Δt i The product is determined, and the direction is along the docking direction of the rear of the mobile chassis toward the charging pile.

[0014] As a further aspect of the present invention, the formula for the feed displacement increment is as follows: ;in, Δs i To control the docking feed displacement increment of cycle i; As a further aspect of the present invention, the method for generating motion commands by superposition is as follows: , ; [ , ] represents the motion command of the mobile chassis within control cycle i.

[0015] As a further aspect of the present invention, the formula for calculating the difference is: , Calculate the compensation displacement increments δ(u) in the X-axis and Y-axis directions within control period i. x，i ) and δ(u y，i ); In the formula, u x，i-1 and u y，i-1 These are the compensation displacements in the X-axis and Y-axis directions, respectively, within the preceding control cycle i adjacent to control cycle i. When i is 1, u x，i-1 and u y，i-1 All values ​​are 0.

[0016] As a further aspect of the present invention, the method for calculating the correction displacement is as follows: The lateral positional deviation and angular deviation of the wired charging interface relative to the charging pile electrode within control cycle i are denoted as e. y，i and e θ，i ; pass: , Calculate the longitudinal correction displacement increment and lateral correction displacement increment In the formula: This is the gain coefficient for lateral position correction. This is the gain coefficient for lateral angle correction. The gain coefficients for longitudinal angle correction are all preset values ​​calibrated through experiments.

[0017] As a further aspect of the present invention, the method for superimposing the correction displacement increments is as follows: , ; [ , ] is the motion command of the mobile chassis after correction within control cycle i.

[0018] A control method for a multi-axis linkage service robot with a rotatable waist, the method comprising the following steps: Step S1, Chassis pre-adjustment: When the controller receives a charging command, it acquires the pre-detected user orientation angle and the target angle required for the waist rotation joint to rotate, and calculates the target orientation angle of the moving chassis. The controller controls the moving chassis to rotate to the target orientation angle first, so that the upper body interaction unit can face the user after the waist rotation is completed. Step S2, Waist Rotation Linkage Connection: The controller sends rotation commands to the waist rotation joints, driving the upper body interaction unit to rotate from the initial angle to the target angle; The total rotation time of the lumbar rotator joint is discretized into multiple control cycles, and the following sub-steps are executed sequentially within each control cycle: Step S2.1, Calculation of centroid compensation displacement increment: The system obtains the position command corresponding to the current control cycle. Based on the pre-calibrated mass of the upper body interaction unit, the total mass of the entire machine, and the position vector of the center of mass of the upper body interaction unit relative to the waist rotation center in the chassis coordinate system, it calculates... The compensation displacement in the X-axis and Y-axis directions at the corresponding angles; calculate the difference in compensation displacement between the current control cycle and the adjacent previous control cycle to obtain the compensation displacement increment to be executed in the current control cycle; Step S2.2, Generation of docking feed displacement increment: Based on the preset docking speed and control cycle duration, calculate the docking feed displacement increment within the corresponding control cycle: Step S2.3, Calculation of displacement increment for deviation correction: By using a deviation detection sensor installed at the wired charging interface, the lateral positional deviation and angular deviation of the wired charging interface relative to the charging pile electrode are obtained, and the longitudinal correction displacement increment and lateral correction displacement increment are calculated: Step S2.4, Instruction Stacking and Execution: By superimposing the compensated displacement increment, the docking feed displacement increment, and the correction displacement increment, the motion command of the moving chassis within the corresponding control cycle is obtained: The controller controls the mobile chassis to move according to the motion command, and can simultaneously achieve center of gravity compensation, docking feed and charging interface deviation correction during waist rotation; Step S3: Cycle continuously until completion: Repeat the sub-steps in step S2 until the waist rotation joint reaches the target angle.

[0019] This invention provides a multi-axis linkage service robot with a rotatable waist and its control method. Compared with the prior art, it has the following advantages: When the robot needs to be charged, the upper body interaction unit is driven by the waist rotation joint to turn to the target angle facing the user, and the chassis is pre-adjusted to turn to the best orientation in advance, ensuring that the human-machine interface is always facing the user, effectively avoiding service interruption caused by charging, and improving the user experience and continuous operation capability in commercial service scenarios.

[0020] By discretizing the waist rotation time into multiple control cycles, the compensation displacement increment is calculated in real time within each control cycle and superimposed on the omnidirectional chassis motion command. This can actively counteract the shift in the center of gravity of the entire machine caused by the upper body rotation, eliminate the risk of chassis swaying and overturning, and ensure a smooth and safe docking process.

[0021] A deviation detection sensor is set at the charging interface, and the displacement correction module dynamically acquires the lateral position deviation and angular deviation, generates longitudinal and lateral correction displacement increments and superimposes them in a closed loop, so that the position deviation between the interface and the electrode converges quickly, improves the success rate and accuracy of one-time docking, and reduces mechanical wear.

[0022] This invention integrates chassis pre-adjustment, waist rotation, center of gravity compensation, docking feed, and deviation correction into a unified multi-axis linkage control method. All movements are coordinated and synchronized, taking into account interactive experience, center of gravity stability, and electrical connection reliability. This enables fully automated autonomous charging and improves the robot's overall performance and scene adaptability. Attached Figure Description

[0023] Figure 1 This is a schematic diagram of a multi-axis linkage service robot with a rotatable waist according to the present invention; Figure 2 This is a structural schematic diagram of a multi-axis linkage service robot with a rotatable waist according to the present invention; Figure 3 This is a flowchart illustrating a control method for a multi-axis linkage service robot with a rotatable waist, according to the present invention.

[0024] In the diagram: 100, mobile chassis; 200, waist rotation joint; 300, upper body interaction unit; 400, controller; 401, waist drive module; 402, center of gravity compensation module; 403, chassis docking module; 404, chassis pre-adjustment module; 405, displacement correction module. Detailed Implementation

[0025] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0026] Please see Figures 1 to 3 As shown, the embodiments of the present invention provide the following technical solutions: As an embodiment of the present invention: This invention relates to a multi-axis linkage service robot with a rotatable waist, comprising: The mobile chassis 100 has a wired charging interface at the rear for docking with a charging pile; the mobile chassis 100 is an omnidirectional mobile chassis. The waist rotation joint 200 is located above the movable chassis 100 and rotates about a vertical axis. The upper body interaction unit 300 is mounted on the waist rotation joint 200 and is equipped with sensors for sensing the environment and the user, including at least one of a depth camera, a lidar, a display screen, and a microphone. The controller 400 includes a waist drive module 401, a center of gravity compensation module 402, a chassis docking module 403, and a chassis pre-adjustment module 404. The controller 400 is installed inside the mobile chassis 100 and is connected to the drive wheel motor, the drive motor in the waist rotation joint 200, and various sensors in the upper body interaction unit 300 of the mobile chassis 100. The waist drive module 401, when the controller 400 receives a charging command, sends a rotation command to the waist rotation joint 200 to drive the upper body interaction unit 300 to rotate from the initial angle to the target angle, so that the orientation of the upper body interaction unit 300 changes from the initial direction to the user-facing direction. The charging pile is equipped with auxiliary positioning markers, and the pre-determined geometric feature pattern of the auxiliary positioning markers ensures that when the sensor in the upper body interaction unit 300 takes a picture at a non-direct angle, the deformation of the geometric feature pattern in the image has a one-to-one correspondence with the shooting angle. The controller calculates the current deflection angle of the sensor relative to the normal vector of the marker plane based on the deformation, and this deflection angle is the target angle. Calculating the deflection angle through deformation is existing technology and is common knowledge in the fields of robot vision servoing and autonomous charging, so it will not be elaborated on. The charging command may be sent in one or more of the following ways: When the power management terminal of the multi-axis linkage service robot detects that the battery level is lower than the preset power threshold, it automatically generates a charging command and sends it to the controller 400. The robot's upper body interaction unit 300 receives user voice commands via a microphone, or user click commands via a touch screen, or charging commands from a remote dispatch terminal via a network module, and sends them to the controller 400. The center of gravity compensation module 402 is used to calculate the overall center of gravity shift caused by the rotation of the upper body interaction unit 300 based on the current waist rotation angle of the waist rotation joint 200, and generate a compensation displacement increment opposite to the direction of the overall center of gravity shift, which is then superimposed on the moving chassis 100; the compensation displacement calculation method is as follows: Obtain the pre-calibrated upper body interaction unit mass m of 300 uThe total mass M of the machine, and the position vector (dx, dy) of the center of mass of the upper body interaction unit 300 relative to the waist rotation center in the chassis coordinate system; The chassis coordinate system is a three-dimensional coordinate system established with the geometric center of the 100 omnidirectional wheel assembly of the mobile chassis as the origin; the X-axis is the longitudinal axis of the chassis, and the Y-axis is the transverse axis of the chassis; the positive direction of the X-axis points to the forward direction of the chassis, and the positive direction of the Y-axis points to one side of the chassis. Get the current waist rotation angle This refers to the real-time angle that the upper body interaction unit 300 has rotated from its initial angle; in this embodiment, the current waist rotation angle... The angle can be read directly from the angle sensor that is pre-set on the lumbar joint via the controller 400; pass: Calculate the horizontal distance r from the center of mass of the upper body interaction unit 300 to the center of rotation of the waist; pass: , When dy=0 and dx=r: , Calculate the compensation displacement u in the X-axis direction. x Compensation displacement u in the Y-axis direction y ; In the formula, ΔX and ΔY represent the offset of the machine's center of gravity in the X-axis and Y-axis directions, respectively. The direction of the center of gravity offset is opposite to the direction of the compensation displacement, i.e. , ; The chassis pre-adjustment module 404 is used to adjust the user's orientation angle θ based on the pre-acquired or detected angle. Y And through: Calculate the target orientation angle θ of the mobile chassis 100. M Where: h is the target angle, and the rotation range of the waist rotation joint 200 is not less than h; Wherein, the user orientation angle θ Y The user's position can be detected and calculated using a depth camera or lidar mounted on the upper body interaction unit, which is existing technology and will not be elaborated upon here. When the waist drive module 401 receives a rotation command, and before the rotation command is executed, the chassis pre-adjustment module 404 controls the mobile chassis 100 to rotate to the target orientation angle θ. M ; The chassis docking module 403 is used to output motion commands to the mobile chassis 100 during the rotation of the waist rotation joint 200, and control the mobile chassis 100 to perform docking feed motion toward the charging pile. The docking feed motion refers to the linear feed motion of the moving chassis at a preset docking speed along the direction of its tail toward the charging pile during the rotation of the upper body interactive unit driven by the waist rotation joint.

[0027] The motion command generation method is as follows: The total rotation time T of the waist rotation joint 200 is discretized into N control cycles. The required compensation displacement increment is calculated in each control cycle, and the compensation displacement increment is superimposed with the docking feed displacement increment to generate the motion command of the mobile chassis 100 in the control cycle. Specifically: The controller 400 sends a corresponding position command to the lumbar rotation joint 200, the position command being to make the lumbar rotation joint 200 reach a predetermined intermediate angle. ,in: , i = 1, 2, ... N, where i is the index of the control cycle number and N is the number of control cycles; Within control period i, the compensation displacements in the X-axis and Y-axis directions are denoted as u, respectively. x，i and u y，i ; in, , ; When dy=0 and dx=r , ; Calculate the compensation displacement in the X-axis and Y-axis directions of control cycle i, and calculate the difference between the compensation displacement in the X-axis and Y-axis directions of the control cycle i-1 that is adjacent to control cycle i, to obtain the compensation displacement increment that needs to be executed in control cycle i. The formula for calculating the difference is: , Calculate the compensation displacement increments δ(u) in the X-axis and Y-axis directions within control period i. x，i ) and δ(u y，i ); In the formula, u x，i-1 and u y，i-1 These are the compensation displacements in the X-axis and Y-axis directions, respectively, within the preceding control cycle i adjacent to control cycle i. When i is 1, u x，i-1 and u y，i-1 All values ​​are 0; Among them, the docking feed displacement is a command directly generated by the controller 400 according to preset parameters; The docking feed displacement increment is determined by the preset docking speed v. d and the duration of the control cycle Δt iThe product is determined, and the direction is along the docking direction of the rear of the mobile chassis 100 toward the charging pile; in, ; The formula for the feed displacement increment is: ; In the formula, Δs i To control the docking feed displacement increment of period i, the docking feed direction is the negative vertical axis of the chassis coordinate system, therefore the docking speed v is taken. d and period duration Δt i The negative value of the product; The method for generating motion commands by superposition is as follows: , ;[ , [] represents the motion command of the mobile chassis 100 within control cycle i; When the robot needs charging, the waist rotation joint 200 can drive the upper body interaction unit 300 to rotate to the target angle facing the user, so that natural interaction with the user can be maintained during the charging process. At the same time, the chassis pre-adjustment module 404 pre-rotates the chassis to the optimal orientation, the center of gravity compensation module 402 calculates and compensates for the overall center of gravity shift in real time when the waist rotates, and the chassis docking module 403 superimposes the compensation displacement increment with the docking feed displacement to ensure stable chassis movement and avoid chassis shaking or overturning caused by upper body rotation, significantly improving the stability and safety of autonomous charging.

[0028] As a second embodiment of the present invention: In its specific implementation, compared to Embodiment 1, the only difference between the technical solution of this embodiment and Embodiment 1 is that in this embodiment, a deviation detection sensor is provided at the wired charging interface of the mobile chassis 100 to detect the lateral positional deviation e of the wired charging interface relative to the charging pile electrode. y and angular deviation e θ ; When the mobile chassis 100 is equipped with a deviation detection sensor, the controller 400 is correspondingly equipped with a displacement correction module 405; The displacement correction module 405 is used to calculate the correction displacement increment based on the lateral position deviation and angular deviation within the control cycle i, and to add the correction displacement increment to the motion command of the mobile chassis 100. The correction displacement calculation method is as follows: The lateral positional deviation and angular deviation of the wired charging interface relative to the charging pile electrode within control cycle i are denoted as e. y，i and e θ，i ; pass: , Calculate the longitudinal correction displacement increment and lateral correction displacement increment ; Where: longitudinal correction displacement increment This refers to the displacement correction component applied to the X-axis direction of the chassis coordinate system within a control cycle i, used to compensate for angular deviation e. θ，i The resulting alignment error of the charging interface in the X-axis direction; lateral correction displacement increment This refers to the displacement correction component applied in the Y-axis direction of the chassis coordinate system within a control cycle i, used to compensate for lateral position deviation e. y，i and angular deviation e θ，i The resulting alignment error of the charging interface in the Y-axis direction; This is the gain coefficient for lateral position correction. This is the gain coefficient for lateral angle correction. The gain coefficients for longitudinal angle correction are all preset values ​​calibrated through experiments, and... , , All are positive numbers and can be identified through step response tests or the least squares method; The negative sign in the formulas for longitudinal and lateral correction displacement increments is used to indicate the direction of negative feedback correction. When e θ，i When >0, <0, meaning that the moving chassis 100 adds a displacement along the negative X-axis to compensate for the longitudinal contact position lag caused by the deflection; When e θ，i When <0, >0, meaning that the moving chassis 100 adds a displacement along the positive X-axis to compensate for the forward extension of the longitudinal contact position caused by the deflection; When e y，i When >0, <0, meaning the moving chassis 100 applies a displacement along the negative Y-axis to pull the wired charging interface back to the center position; When e θ，i When the value is greater than 0, the additional lateral offset caused by the deflection tends to move the wired charging interface in the positive Y-axis direction. The item provides a negative correction, causing the moving chassis 100 to move in the opposite direction to counteract the offset; pass: , The corrected displacement increment is superimposed on the motion command of the mobile chassis 100 to obtain the corrected motion command of the mobile chassis 100 within control cycle i. , ].

[0029] By adding a deviation detection sensor at the charging interface, the lateral position and angle deviations are acquired in real time. The displacement correction module 405 dynamically generates longitudinal and lateral correction displacement increments, which are then superimposed on the chassis motion command. This closed-loop correction mechanism can effectively compensate for accumulated errors during the docking process, enabling the positional deviation between the interface and the charging pile electrodes to converge rapidly. This improves the success rate of first-time docking, reduces mechanical wear and time consumption caused by repeated adjustments, and enhances the accuracy and robustness of charging docking.

[0030] As an embodiment of the present invention: In specific implementation, compared with Embodiment 1 and Embodiment 2, the technical solution of this embodiment is to combine the solutions of Embodiment 1 and Embodiment 2.

[0031] The present invention also provides a control method for a multi-axis linkage service robot with a rotatable waist. The method is implemented using a multi-axis linkage service robot with a rotatable waist and includes the following steps: Step S1, Chassis pre-adjustment: When the controller 400 receives a charging command, it acquires the pre-detected user orientation angle and the target angle that the waist rotation joint 200 needs to rotate, and calculates the target orientation angle of the mobile chassis 100; the controller 400 controls the mobile chassis 100 to rotate to the target orientation angle first, so that the upper body interaction unit 300 can face the user after the waist rotation is completed. Step S2, Waist-rotation linkage docking: The controller 400 sends a rotation command to the waist rotation joint 200, driving the upper body interaction unit 300 to rotate from the initial angle to the target angle; The total rotation time of the lumbar rotation joint 200 is discretized into multiple control cycles, and the following sub-steps are executed sequentially within each control cycle: Step S2.1, Calculation of centroid compensation displacement increment: The position command corresponding to the current control cycle is obtained. Based on the pre-calibrated mass of the upper body interaction unit 300, the total mass of the entire machine, and the position vector of the center of mass of the upper body interaction unit 300 relative to the waist rotation center in the chassis coordinate system, the following calculation is performed: The compensation displacement in the X-axis and Y-axis directions at the corresponding angles; calculate the difference in compensation displacement between the current control cycle and the adjacent previous control cycle to obtain the compensation displacement increment to be executed in the current control cycle; Step S2.2, Generation of docking feed displacement increment: Based on the preset docking speed and control cycle duration, calculate the docking feed displacement increment within the corresponding control cycle: Step S2.3, Calculation of deviation correction displacement increment: By using a deviation detection sensor installed at the wired charging interface, the lateral positional deviation and angular deviation of the wired charging interface relative to the charging pile electrode are obtained, and the longitudinal correction displacement increment and lateral correction displacement increment are calculated: Step S2.4, Instruction Stacking and Execution: The compensation displacement increment, the docking feed displacement increment, and the correction displacement increment are superimposed to obtain the motion command of the moving chassis 100 within the corresponding control cycle: The controller 400 controls the mobile chassis 100 to move according to the motion command, and can simultaneously achieve center of gravity compensation, docking feed and charging interface deviation correction during the waist rotation process; Step S3: Cycle continuously until completion: Repeat the sub-steps in step S2 until the waist rotation joint 200 reaches the target angle to complete the charging docking process.

[0032] After all the steps, the upper body interaction unit 300 gradually turns towards the user as the waist rotation joint 200 rotates, and the field of vision of the sensors it carries gradually covers the user area, so as to keep an eye on the user and the environment while gradually approaching the charging pile. In addition, when the charging interface electrode and the charging pile are connected by the charging current, and the controller 400 confirms that the charging docking is successful, it locks the waist rotation joint 200 and keeps the upper body interaction unit 300 facing the same direction, and the multi-axis linkage service robot enters the charging state. During charging, the sensors continue to operate, performing environmental monitoring and user interaction.

[0033] Furthermore, any content not described in detail in this specification is existing technology known to those skilled in the art.

[0034] It should be noted that, in this document, relational terms such as "first" and "second" are used only to distinguish one entity or operation from another, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Furthermore, the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such process, method, article, or apparatus.

[0035] Although embodiments of the invention have been shown and described, it will be understood by those skilled in the art that various changes, modifications, substitutions and alterations can be made to these embodiments without departing from the principles and spirit of the invention, the scope of which is defined by the appended claims and their equivalents.

[0036] The various embodiments of this application have been described above. These descriptions are exemplary and not exhaustive, nor are they limited to the disclosed embodiments. Many modifications and variations will be apparent to those skilled in the art without departing from the scope and spirit of the described embodiments. The terminology used herein is chosen to best explain the principles, practical application, or improvement of the technology in the market, or to enable others skilled in the art to understand the embodiments disclosed herein.

Claims

1. A multi-axis linkage service robot with a rotatable waist, characterized in that, include: The mobile chassis (100) has a wired charging interface at the rear for docking with a charging pile; A waist rotation joint (200) is disposed above the movable chassis (100) and rotates about a vertical axis; The upper body interaction unit (300) is located above the waist rotation joint (200) and is equipped with sensors for sensing the environment and the user; Controller (400), the controller (400) is installed inside the mobile chassis (100) and includes: The waist drive module (401) is used to send a rotation command to the waist rotation joint (200) when the controller (400) receives a charging command, thereby driving the upper body interaction unit (300) to rotate from the initial angle to the target angle. The center of gravity compensation module (402) is used to calculate the offset of the whole machine's center of gravity caused by the rotation of the upper body interaction unit (300) based on the current waist rotation angle of the waist rotation joint (200), and generate a compensation displacement increment opposite to the offset direction of the whole machine's center of gravity and superimpose it on the mobile chassis (100). The chassis docking module (403) is used to output motion commands to the mobile chassis (100) during the rotation of the waist rotation joint (200) to control the mobile chassis (100) to perform docking feed motion toward the charging pile. The motion command generation method is as follows: the total rotation time T of the waist rotation joint (200) is discretized into N control cycles, the required compensation displacement increment is calculated in each control cycle, and the compensation displacement increment is superimposed with the docking feed displacement increment to generate the motion command of the mobile chassis (100) in the control cycle, as follows: The controller (400) sends a corresponding position command to the lumbar rotation joint (200), the position command being to make the lumbar rotation joint (200) reach a predetermined intermediate angle. , Within control period i, the compensation displacements in the X-axis and Y-axis directions are denoted as u, respectively. x，i and u y，i Let i = 1, 2, ..., N, where i is the index of the control cycle number and N is the number of control cycles. Calculate the compensation displacement in the X-axis and Y-axis directions of control cycle i, and subtract the compensation displacement in the X-axis and Y-axis directions of the preceding control cycle i-1 to obtain the compensation displacement increment that control cycle i needs to perform in the X-axis and Y-axis directions. The docking feed displacement increment is determined by the preset docking speed v. d and the duration of the control cycle Δt i The product is determined by the fact that the product takes a negative value, which indicates that the feed motion is along the negative direction of the longitudinal axis in the chassis coordinate system; The chassis pre-adjustment module (404) is used to determine the target orientation angle of the mobile chassis (100) based on the pre-detected user orientation angle; and to control the mobile chassis (100) to rotate to the target orientation angle.

2. The multi-axis linkage service robot with a rotatable waist as described in claim 1, characterized in that: The compensation displacement is calculated as follows: Obtain the pre-calibrated mass m of the upper body interaction unit (300). u The total mass M of the machine and the position vector (dx,dy) of the center of mass of the upper body interaction unit (300) relative to the waist rotation center in the chassis coordinate system; The real-time angle that the upper body interaction unit (300) has rotated from the initial angle is obtained and set as the current waist rotation angle. ; pass: , Calculate the compensation displacement u in the X-axis direction. x Compensation displacement u in the Y-axis direction y ; In the formula, ΔX and ΔY are the offsets of the machine's center of mass in the X-axis and Y-axis directions, respectively.

3. The multi-axis linkage service robot with a rotatable waist as described in claim 1, characterized in that: The controller (400) also includes: a displacement correction module (405) that calculates the correction displacement increment based on the lateral position deviation and the angular deviation, and adds the correction displacement increment to the motion command of the mobile chassis (100); The wired charging interface of the mobile chassis (100) is equipped with a deviation detection sensor to detect the lateral position deviation and angular deviation of the wired charging interface relative to the charging pile electrode.

4. A multi-axis linkage service robot with a rotatable waist as described in claim 3, characterized in that: The correction displacement is calculated as follows: The lateral positional deviation and angular deviation of the wired charging interface relative to the charging pile electrode within control cycle i are denoted as e. y，i and e θ，i ; pass: , Calculate the longitudinal correction displacement increment and lateral correction displacement increment In the formula: This is the gain coefficient for lateral position correction. This is the gain coefficient for lateral angle correction. The gain coefficients for longitudinal angle correction are all preset values ​​calibrated through experiments.

5. A multi-axis linkage service robot with a rotatable waist as described in claim 1, characterized in that: Intermediate angle value within control cycle i The target angle is obtained by multiplying the current control cycle number i and then dividing by the total number of control cycles.

6. A multi-axis linkage service robot with a rotatable waist as described in claim 1, characterized in that: When i is 1, the compensation displacement in the X-axis and Y-axis directions in the preceding control cycle i adjacent to control cycle i is 0.

7. A multi-axis linkage service robot with a rotatable waist as described in claim 1, characterized in that: The target orientation angle is obtained by subtracting the target angle from the user orientation angle; The rotation range of the waist rotation joint (200) is not less than the target angle value.

8. A multi-axis linkage service robot with a rotatable waist as described in claim 7, characterized in that: When the waist drive module (401) receives a rotation command, and before the rotation command is executed, the chassis pre-adjustment module (404) controls the mobile chassis (100) to rotate to the target orientation angle.

9. A control method for a multi-axis linkage service robot with a rotatable waist, characterized in that, This method is achieved using a multi-axis linkage service robot with a rotatable waist, as described in any one of claims 1-8.

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