Robot walking control method, system and robot

Abstract

The application provides a robot walking control method, a system and a robot. The robot walking control method comprises the following steps: acquiring an inner radius of a container and a liquid level of a liquid in the container; calculating a liquid surface sloshing frequency according to the inner radius of the container and the liquid level; determining acceleration and deceleration constraint parameters in a conventional walking process of the robot according to the liquid surface sloshing frequency; generating a speed curve corresponding to a walking path based on an S-shaped speed planning mode, in combination with the pre-planned walking path, the acceleration and deceleration constraint parameters and a maximum allowed speed; and controlling the robot to walk along the walking path according to the speed curve. In the embodiment of the application, the splashing risk of the liquid during the delivery process can be reduced.

Description

Technical Field

[0001] This application relates to the field of robotics technology, and in particular to a robot walking control method, system, and robot. Background Technology

[0002] With the rapid development of robotics technology, delivery robots used for food and beverage delivery have been gradually applied in restaurants, hotels, cafes, large office spaces and other scenarios.

[0003] However, when delivery robots are tasked with delivering beverages such as coffee, they are prone to spilling liquids, resulting in beverage loss and environmental pollution.

[0004] How to reduce the risk of liquid spillage during the delivery of beverages by delivery robots is an urgent problem to be solved. Summary of the Invention

[0005] In view of this, this application aims to propose a robot walking control method, system and robot to reduce the risk of liquid spillage during delivery.

[0006] According to a first aspect of this application, a robot walking control method is provided, the robot including a mobile chassis and a tray, the tray being used to carry a container filled with liquid; The robot walking control method includes: Obtain the inner radius of the container and the liquid level inside the container; The frequency of liquid surface sloshing is calculated based on the inner radius of the container and the liquid level. The acceleration and deceleration constraint parameters during the robot's normal walking process are determined based on the liquid surface sloshing frequency. Based on the S-shaped speed planning method, and combined with the pre-planned walking path, the acceleration and deceleration constraint parameters, and the maximum allowable speed, the speed curve corresponding to the walking path is generated. The robot is controlled to walk along the walking path based on the speed curve.

[0007] In this embodiment, the acceleration and deceleration constraint parameters during the robot's normal walking process are determined based on the liquid surface sloshing frequency. This constrains the robot's acceleration and deceleration during normal walking, preventing excessive acceleration and deceleration that could cause significant liquid sloshing and spillage during delivery. This reduces the amplitude of liquid sloshing during delivery, thereby lowering the risk of liquid spillage. Furthermore, a higher liquid surface sloshing frequency results in better liquid stability, making spillage less likely. The acceleration and deceleration constraint parameters can be appropriately increased to ensure delivery efficiency while preventing spillage. Additionally, the use of an S-shaped speed planning method makes the changes in the robot's speed, acceleration, and deceleration smoother, further reducing the risk of liquid spillage.

[0008] Optionally, controlling the robot to walk along the walking path according to the speed curve includes: If the walking path has at least one turning segment, and the estimated speed of the robot when it walks to the turning segment is greater than the maximum turning speed allowed during the robot's normal walking process, the speed curve is updated when the robot walks a preset distance before reaching the turning segment, and the robot is controlled to walk along the walking path according to the updated speed curve. Wherein, a continuous turning section is one turning section; the updated speed curve is used to: decelerate the robot when it travels a preset distance before the turning section, reduce the robot's speed when it travels to the turning section to the maximum turning speed, and accelerate the robot to the speed before deceleration after passing the turning section.

[0009] Optionally, the formula for calculating the maximum permissible turning speed during the robot's normal walking process is:

[0010] in, For the maximum permissible turning speed, The unit is m / s. For the maximum permissible centripetal acceleration, The unit is m / s 2 , The radius of the turning section. The unit is m; The formula for calculating the maximum permissible centripetal acceleration is:

[0011] in, It is the acceleration due to gravity. The value is m / s 2 , The value is 9.81 m / s 2 , This refers to the remaining height inside the container. The unit is m. Let be the inner radius of the container. The unit is m.

[0012] Optionally, the acceleration / deceleration constraint parameters include at least one of the following: upper limit of acceleration, upper limit of deceleration, upper limit of rate of change of acceleration, and upper limit of rate of change of deceleration; The step of determining the acceleration and deceleration constraint parameters during the robot's normal walking process based on the liquid surface sloshing frequency includes: The upper limit of acceleration during the robot's normal walking process is determined based on the frequency of liquid surface sloshing. And / or, determine the upper limit of deceleration during the robot's normal walking process based on the liquid surface sloshing frequency; And / or, determine the upper limit of the rate of change of acceleration during the robot's normal walking process based on the liquid surface sloshing frequency; And / or, determine the upper limit of the rate of change of deceleration during the robot's normal walking process based on the liquid surface sloshing frequency.

[0013] Optionally, the formula for calculating the upper limit of acceleration is:

[0014] in, The upper limit of acceleration, The unit is m / s 2 , For safety reasons, The value is 0.7. The frequency of liquid surface sloshing. The unit is Hz. The maximum allowable sway amplitude, The value is 0.005m; The formula for calculating the upper limit of deceleration is:

[0015] in, The upper limit of deceleration, The unit is m / s 2 ; set up For the maximum permissible speed, The unit is m / s. , For a pre-set safe distance, The unit is m. , This is the margin distance. The value ranges from 0.1m to 0.3m. The maximum speed is the chassis's rated speed. The unit is m / s; Less than hour, ; Greater than or equal to hour, .

[0016] Optionally, the formula for calculating the liquid surface sloshing frequency is:

[0017] in, The frequency of liquid surface sloshing. The unit is Hz. The value is 3.14. It is the acceleration due to gravity. The value is 9.81 m / s 2 , Let be the inner radius of the container. The unit is m. The liquid level inside the container. The unit is m.

[0018] Optionally, the mobile chassis includes a chassis body and wheels. The wheels are connected to the chassis body via an active suspension structure. A vertical acceleration sensor is installed on the chassis body to detect the vertical acceleration of the chassis body. The robot walking control method is executed by the main control module. During the robot's walking along the walking path, the main control module periodically acquires the vertical acceleration of the chassis body. When the absolute value of the vertical acceleration is greater than or equal to a first set value, the main control module controls the damping of the active suspension structure to increase from the preset basic damping to the first set damping. When the absolute value of the vertical acceleration is less than or equal to a second set value for a continuous set time, the main control module controls the damping of the active suspension structure to return to the preset basic damping.

[0019] Optionally, before obtaining the inner radius of the container and the liquid level inside the container, the method further includes: In response to a container containing liquid being placed on the tray, a first total weight of the container and the liquid inside the container is obtained; After controlling the robot to walk along the walking path according to the speed curve, the method further includes: After the robot walks to the end of the walking path, the second total weight of the container and the liquid inside the container is obtained; The difference between the first total weight and the second total weight is taken as the liquid loss. The liquid surface sloshing frequency, the acceleration / deceleration constraint parameters, and the liquid loss amount are recorded as historical delivery data.

[0020] According to a second aspect of this application, a robot walking control system is also provided, including a main control module, the main control module being used to execute the robot walking control method described above.

[0021] According to a third aspect of this application, a robot is also provided, including the robot walking control system described above.

[0022] The above description is only an overview of the technical solution of this application. In order to better understand the technical means of this application and to implement it in accordance with the contents of the specification, and to make the above and other objects, features and advantages of this application more obvious and understandable, the following are specific embodiments of this application. Attached Figure Description

[0023] Various other advantages and benefits will become apparent to those skilled in the art upon reading the following detailed description of preferred embodiments. The accompanying drawings are for illustrative purposes only and are not intended to limit the scope of this application. Furthermore, the same reference numerals denote the same parts throughout the drawings. In the drawings: Figure 1 This is a flowchart illustrating the steps of a robot walking control method provided in an embodiment of this application; Figure 2 This is a flowchart of another robot walking control method provided in an embodiment of this application; Figure 3 This is a structural block diagram of a robot walking control system provided in an embodiment of this application. Detailed Implementation

[0024] To make the objectives, technical solutions, and advantages of the embodiments of this application clearer, the various embodiments of this application will be described in detail below with reference to the accompanying drawings. However, those skilled in the art will understand that many technical details have been presented in the various embodiments of this application to enable readers to better understand this application. However, even without these technical details and various changes and modifications based on the following embodiments, the technical solutions claimed in this application can be implemented. The division of the various embodiments below is for the convenience of description and should not constitute any limitation on the specific implementation of this application. The various embodiments can be combined with and referenced by each other without contradiction.

[0025] This application provides a robot walking control method for controlling the walking of a robot, which can be a coffee robot, a food delivery robot, or other delivery robots.

[0026] The robot includes a mobile chassis, which comprises a chassis body, wheels, a drive motor, and a motor driver. The wheels are mounted on the chassis body, and the drive motor is connected to the wheels via a transmission mechanism. The drive motor drives the wheels to rotate, and the motor driver is electrically connected to the drive motor. The motor driver controls the operation of the drive motor, thereby controlling the movement of the mobile chassis.

[0027] The robot also includes a tray, which is used to hold containers filled with liquids. The liquids can be beverages such as coffee, milk, milk tea, or tea, or soups. The containers can be bowls, cups, bottles, etc., and specifically, open-top containers.

[0028] The robot also includes a main control module, and the motor driver is electrically connected to the main control module. The robot's walking control method can be executed by the main control module in the robot.

[0029] Reference Figure 1 The diagram illustrates a flowchart of a robot walking control method according to an embodiment of this application. The robot walking control method includes: S101, obtain the inner radius of the container and the liquid level inside the container.

[0030] Before obtaining the inner radius of the container and the liquid level inside the container, the container filled with liquid has been placed on the tray.

[0031] The container can be a cylindrical cup with a uniform inner diameter along its height, and its inner radius is half the inner diameter of the cylindrical cup. For containers with inconsistent inner diameters along their height, the inner radius can be half the average inner diameter of the container.

[0032] The robot also features a display screen where users can select container sizes. The main control module determines the container's inner radius based on the user-selected size and a pre-stored correspondence between container sizes and their inner radii. Container sizes can include standard, medium, and large cups. It's understood that the container's inner radius can be directly input by the user.

[0033] The robot also includes a liquid level detector, which is electrically connected to the main control module. The liquid level detector can be an ultrasonic sensor, laser rangefinder, etc. It detects the distance between the liquid surface in the container and the detector itself, and sends this information to the main control module. The main control module then determines the liquid level in the container based on this distance, a preset distance between the detector and the tray, and a preset container bottom wall thickness. Liquid level refers to the height of the liquid surface relative to the bottom of the container.

[0034] S102, calculate the liquid surface sloshing frequency based on the inner radius of the container and the liquid level.

[0035] The liquid surface sloshing frequency is used to characterize the inherent characteristic of liquid sloshing under disturbance in a container. The liquid surface sloshing frequency can be the first-order natural sloshing frequency of the liquid in the container.

[0036] For a cylindrical cup, the formula for calculating the frequency of liquid surface sloshing is:

[0037] in, The frequency of liquid surface sloshing. The unit is Hz. The value is 3.14. It is the acceleration due to gravity. The value is 9.81 m / s 2 , Let be the inner radius of the container. The unit is m. This represents the liquid level inside the container. The unit is m. It is the hyperbolic tangent function.

[0038] S103, determine the acceleration and deceleration constraint parameters during the robot's normal walking process based on the liquid surface sloshing frequency.

[0039] The robot's normal walking process refers to the walking process without emergency stop, obstacle avoidance braking, or forced braking. Acceleration and deceleration constraint parameters may include at least one of the following: upper limit of acceleration, upper limit of deceleration, upper limit of rate of change of acceleration, and upper limit of rate of change of deceleration.

[0040] Acceleration refers to the rate at which a robot's walking speed increases over time, while deceleration refers to the rate at which its walking speed decreases over time. The rate of change of acceleration refers to the rate of change of acceleration over time, and the rate of change of deceleration refers to the rate of change of deceleration over time. The upper limit of acceleration refers to the maximum allowable acceleration during normal robot movement; this upper limit is less than or equal to the chassis's rated maximum acceleration. The upper limit of deceleration refers to the maximum allowable deceleration during normal robot movement; this upper limit is less than or equal to the chassis's rated maximum deceleration. The upper limit of the rate of change of acceleration refers to the maximum absolute value of the allowable rate of change of acceleration during normal robot movement, and the upper limit of the rate of change of deceleration refers to the maximum absolute value of the allowable rate of change of deceleration during normal robot movement.

[0041] The lower the liquid surface sloshing frequency, the more easily the liquid will slosh during robot acceleration, deceleration, or turning, and the more likely it is to spill. Therefore, the acceleration and deceleration constraint parameters need to be reduced. Conversely, the higher the liquid surface sloshing frequency, the better the liquid stability and the less likely it is to spill during delivery. The acceleration and deceleration constraint parameters can be appropriately increased. Therefore, the lower the liquid surface sloshing frequency, the smaller the acceleration and deceleration constraint parameters should be.

[0042] S104, based on the S-shaped velocity planning method, and combined with the pre-planned walking path, acceleration and deceleration constraint parameters, and the maximum allowable speed, generates the velocity curve corresponding to the walking path. The velocity curve is a time-dependent curve of velocity change.

[0043] The pre-planned delivery route includes a starting point and an ending point. The starting point is preset, while the ending point can be selected by the user via a display screen. Based on the starting and ending points, the main control module can automatically plan the delivery route. The maximum allowed speed can be preset or calculated.

[0044] S-curve velocity planning is a method of planning the robot's velocity change process according to an S-shaped velocity curve. The S-curve velocity curve includes seven stages: positive acceleration stage (acceleration gradually increases from 0); constant acceleration stage (acceleration remains at its maximum value); negative acceleration stage (acceleration gradually decreases to 0); constant velocity stage (velocity remains constant); negative acceleration stage (deceleration gradually increases from 0); constant deceleration stage (deceleration remains at its maximum value); and positive acceleration stage (deceleration gradually decreases to 0). Correspondingly, the velocity curve generated for the walking path is an S-shaped velocity curve.

[0045] Preferably, in the velocity curve, the maximum velocity reaches the aforementioned maximum permissible velocity, the maximum acceleration reaches the aforementioned upper limit of acceleration, the maximum deceleration reaches the aforementioned upper limit of deceleration, the absolute value of the maximum rate of change of acceleration reaches the aforementioned upper limit of rate of change of acceleration, and the absolute value of the maximum rate of change of deceleration reaches the aforementioned upper limit of rate of change of deceleration.

[0046] S105 controls the robot to walk along the walking path based on the speed curve.

[0047] Specifically, a walking control command is generated based on the speed curve and sent to the motor driver. The motor driver controls the operation of the drive motor based on the control command, thereby controlling the movement of the mobile chassis.

[0048] In this embodiment, the acceleration and deceleration constraint parameters during the robot's normal walking process are determined based on the liquid surface sloshing frequency. This constrains the robot's acceleration and deceleration during normal walking, preventing excessive acceleration and deceleration that could cause significant liquid sloshing and spillage during delivery. This reduces the amplitude of liquid sloshing during delivery, thereby lowering the risk of liquid spillage. Furthermore, a higher liquid surface sloshing frequency results in better liquid stability, making spillage less likely. The acceleration and deceleration constraint parameters can be appropriately increased to ensure delivery efficiency while preventing spillage. Additionally, the use of an S-shaped speed planning method makes the changes in the robot's speed, acceleration, and deceleration smoother, further reducing the risk of liquid spillage.

[0049] In some embodiments, controlling the robot to walk along a walking path according to a speed curve includes: If the walking path has at least one turning segment, and the estimated speed of the robot when it reaches the turning segment is greater than the maximum allowable turning speed during normal robot movement, the speed curve is updated when the robot travels a preset distance before reaching the turning segment. The robot is then controlled to walk along the walking path based on the updated speed curve. The updated speed curve is used to: begin decelerating the robot when it reaches the preset distance before the turning segment, reduce the robot's speed to the maximum turning speed when it reaches the turning segment, and accelerate the robot back to its pre-deceleration speed after passing the turning segment. In this embodiment, by limiting the turning speed of the robot when it reaches the turning segment, the centripetal acceleration during turning can be limited, thereby effectively preventing liquid from spilling due to centrifugal force.

[0050] Specifically, before reaching the turning section, the robot decelerates uniformly at a deceleration rate less than or equal to the aforementioned upper limit. While approaching the turning section, the robot maintains a constant speed at its maximum turning speed. After passing the turning section, the robot accelerates uniformly at the aforementioned upper limit. The difference between the updated and unupdated speed curves is that the unupdated speed curve was an S-shaped curve, while the updated speed curve includes a speed change segment of deceleration, constant speed, and acceleration during the time period corresponding to the turning section.

[0051] In this system, consecutive turning segments are treated as a single turning segment, meaning multiple consecutive turning segments are processed as a whole. The estimated speed of the robot when approaching a turning segment can be determined based on the speed curve. The preset distance is set according to actual needs, and must ensure that even if the robot approaches the turning segment at its maximum speed, it can decelerate to its maximum turning speed within the preset distance. For different turning segments, the maximum allowable turning speed can be calculated based on the maximum allowable centripetal acceleration and the radius of the turning segment, or it can be a pre-set fixed value that meets the requirements of different turning segments.

[0052] Understandably, when the walking path does not have turning sections, the robot can be controlled to walk along the walking path directly according to the speed curve.

[0053] In some embodiments, the formula for calculating the maximum permissible turning speed during normal robot walking is:

[0054] in, For the maximum permissible turning speed, The unit is m / s. For the maximum permissible centripetal acceleration, The unit is m / s 2 , The radius of the turning section. The unit is m.

[0055] The formula for calculating the maximum centripetal acceleration is:

[0056] in, It is the acceleration due to gravity. The value is m / s 2 , The value is 9.81 m / s 2 , This refers to the remaining height inside the container. The unit is m. Let be the inner radius of the container. The unit is meters (m). The remaining height inside the container is specifically equal to the difference between the height of the cavity inside the container and the liquid level.

[0057] In some embodiments, the acceleration / deceleration constraint parameters include at least one of an upper limit for acceleration, an upper limit for deceleration, an upper limit for the rate of change of acceleration, and an upper limit for the rate of change of deceleration. Preferably, the acceleration / deceleration constraint parameters include an upper limit for acceleration, an upper limit for deceleration, an upper limit for the rate of change of acceleration, and an upper limit for the rate of change of deceleration. In this case, during the delivery process, not only acceleration and deceleration are constrained, but also the rate of change of acceleration and the rate of change of deceleration are constrained, which can further reduce the risk of liquid spillage.

[0058] The acceleration and deceleration constraint parameters for the robot's normal walking process are determined based on the liquid surface sloshing frequency, including: determining the upper limit of acceleration for the robot's normal walking process based on the liquid surface sloshing frequency; and / or, determining the upper limit of deceleration for the robot's normal walking process based on the liquid surface sloshing frequency; and / or, determining the upper limit of the rate of change of acceleration for the robot's normal walking process based on the liquid surface sloshing frequency; and / or, determining the upper limit of the rate of change of deceleration for the robot's normal walking process based on the liquid surface sloshing frequency.

[0059] In some embodiments, the formula for calculating the upper limit of acceleration is:

[0060] in, The upper limit of acceleration, The unit is m / s 2 , For safety reasons, The value is 0.7. The frequency of liquid surface sloshing. The unit is Hz. The maximum allowable sway amplitude, The value is 0.005m.

[0061] In some embodiments, the formula for calculating the upper limit of deceleration is:

[0062] in, The upper limit of deceleration, The unit is m / s 2 .

[0063] In some embodiments, setting For the maximum permissible speed, The unit is m / s. , For a pre-set safe distance, The unit is m. , This is the margin distance. The value ranges from 0.1m to 0.3m. The maximum speed is the chassis's rated speed. The unit is m / s; Less than hour, ; Greater than or equal to hour, .

[0064] The robot also includes obstacle detectors, which are used to detect whether there are obstacles in front of the robot and the distance between the obstacle and the robot when it is moving. Obstacle detectors can be lidar, ultrasonic sensors, etc. The detection range of the obstacle detector is greater than or equal to the safe distance to ensure that the robot can detect the obstacle before it enters the obstacle at a safe distance.

[0065] When the robot is moving, if an obstacle is detected ahead, and the distance between the robot and the obstacle is greater than or equal to a safe distance, the robot will decelerate smoothly until it stops when it reaches the safe distance from the obstacle. The robot will stop safely in front of the obstacle, and the distance between the robot and the obstacle after stopping will not be less than the margin distance. Specifically, when the robot stops safely in front of the obstacle, and the distance between the robot and the obstacle after stopping is equal to the margin distance, the braking distance traveled by the robot from the start of deceleration to a complete stop is equal to... .

[0066] The safety distance is set according to actual needs. The safety distance must be such that even if the robot walks at the chassis's rated maximum speed and begins to decelerate when it reaches a safe distance from the obstacle, it can still safely stop in front of the obstacle.

[0067] In this embodiment, the maximum speed of the robot during movement is limited to less than or equal to... This allows the robot to decelerate smoothly to a safe stop when it reaches a safe distance from an obstacle and begins to slow down, without exceeding the deceleration limit. This avoids liquid spillage caused by excessive deceleration during obstacle avoidance braking, thus reducing the risk of liquid spillage.

[0068] Understandably, during the robot's movement, there may be situations where moving obstacles suddenly appear in front of the robot and the distance between the robot and the obstacle is less than the safe distance. In this case, the robot will be controlled to decelerate urgently at the chassis's rated maximum deceleration to prioritize emergency obstacle avoidance.

[0069] In some embodiments, .

[0070] In some embodiments, the upper limit of the rate of change of acceleration can be determined based on a pre-stored correspondence between the liquid surface sloshing frequency and the upper limit of the rate of change of acceleration; the upper limit of the rate of change of deceleration can be determined based on a pre-stored correspondence between the liquid surface sloshing frequency and the upper limit of the rate of change of deceleration.

[0071] In some embodiments, the mobile chassis includes a chassis body and wheels. The wheels are connected to the chassis body via an active suspension structure. A vertical acceleration sensor is mounted on the chassis body to detect the vertical acceleration of the chassis body. The active suspension structure may include a damping element and a damping adjustment element. The damping adjustment element is electrically connected to a damping controller. The main control module can send control commands to the damping controller to control the operation of the damping adjustment element, thereby controlling the damping magnitude of the damping element.

[0072] The robot walking control method is executed by the main control module. During the robot's walking along the walking path, the main control module periodically acquires the vertical acceleration of the chassis body. When the absolute value of the vertical acceleration is greater than or equal to the first set value, the module controls the damping of the active suspension structure to increase from the preset basic damping to the first set damping. When the absolute value of the vertical acceleration is less than or equal to the second set value for a continuous set time, the module controls the damping of the active suspension structure to return to the preset basic damping.

[0073] The first set damping is greater than the preset base damping. Both the preset base damping and the first set damping can be set according to actual needs. Initially, the active suspension structure operates with a preset basic damping. When the robot walks on a flat surface, the vertical acceleration value is small and the fluctuation amplitude is small, with the absolute value of the vertical acceleration less than or equal to a second preset value. When the robot walks on an uneven surface, such as a bump or pothole, the vertical acceleration changes significantly. For example, the vertical acceleration suddenly increases and then rebounds, decreasing and oscillating attenuation; or the vertical acceleration suddenly decreases and then rebounds, increasing and oscillating attenuation. After the sudden increase or decrease, the absolute value of the vertical acceleration will be greater than or equal to a first preset value. At this time, the main control module determines that the road surface is bumpy and controls the damping of the active suspension structure to increase from the preset basic damping to the first preset damping to enhance the damping effect of the active suspension structure on vertical vibration, thereby reducing the fluctuation amplitude of the liquid surface and thus reducing the risk of liquid spillage. After the robot passes through the uneven surface, the vertical acceleration returns to a small value and a small fluctuation amplitude, with the absolute value of the vertical acceleration continuously less than or equal to the second preset value for a set time. At this time, the main control module determines that the road surface is relatively flat and controls the damping of the active suspension structure to return to the preset basic damping.

[0074] In some embodiments, refer to Figure 2 This document illustrates a flowchart of another robot walking control method provided in an embodiment of this application. The robot walking control method includes: S201, in response to a container containing liquid being placed on a tray, obtain the first total weight of the container and the liquid inside the container; S202, obtain the inner radius of the container and the liquid level inside the container; S203, calculate the liquid surface sloshing frequency based on the inner radius of the container and the liquid level; S204, Determine the acceleration and deceleration constraint parameters during the robot's normal walking process based on the liquid surface sloshing frequency; S205, based on the S-shaped speed planning method, and combined with the pre-planned walking path, the acceleration and deceleration constraint parameters, and the maximum allowable speed, generates the speed curve corresponding to the walking path; S206, Control the robot to walk along the walking path according to the speed curve; S207, After the robot walks to the end of the walking path, obtain the second total weight of the container and the liquid inside the container; S208, the difference between the first total weight and the second total weight is taken as the liquid loss; S209 records the liquid surface sloshing frequency, acceleration and deceleration constraint parameters, and liquid loss as historical delivery data.

[0075] Specifically, a weight detector is installed on the tray to detect the total weight of the container and the liquid inside. The spill prevention effect can be evaluated based on the amount of liquid loss. By recording the liquid surface sloshing frequency, acceleration / deceleration constraint parameters, and liquid loss during multiple deliveries, multiple historical delivery data points can be generated. Based on these historical delivery data, if the liquid loss is significant, the acceleration / deceleration constraint parameters corresponding to the liquid surface sloshing frequency can be corrected. This corrected acceleration / deceleration constraint parameters can then be used for subsequent control, thereby optimizing the spill prevention effect.

[0076] Reference Figure 3 In another embodiment provided in this application, a robot walking control system is also provided, including the aforementioned main control module, which is used to execute the aforementioned robot walking control method. The robot walking control system also includes the aforementioned motor driver, liquid level detector, and obstacle detector.

[0077] In some embodiments, the robot walking control system further includes the aforementioned vertical acceleration sensor and damping controller. The robot walking control system also includes the aforementioned weight detector.

[0078] In another embodiment provided in this application, a robot is also provided, including the aforementioned robot walking control system. This robot can be a delivery robot such as a coffee robot or a food delivery robot.

[0079] It should be noted that, in this document, relational terms such as "first" and "second" are used merely 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 a process, method, article, or apparatus. Without further limitations, an element defined by the phrase "comprising one..." does not exclude the presence of other identical elements in the process, method, article, or apparatus that includes the element.

[0080] The various embodiments in this specification are described in a related manner. Similar or identical parts between embodiments can be referred to mutually. Each embodiment focuses on describing the differences from other embodiments. In particular, the system embodiments are basically similar to the method embodiments, so the description is relatively simple; relevant parts can be referred to the descriptions of the method embodiments.

[0081] The above are merely preferred embodiments of this application and are not intended to limit the scope of protection of this application. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of this application are included within the scope of protection of this application.

Claims

1. A robot walking control method, characterized in that, The robot includes a mobile chassis and a tray for carrying containers filled with liquid; The robot walking control method includes: Obtain the inner radius of the container and the liquid level inside the container; The frequency of liquid surface sloshing is calculated based on the inner radius of the container and the liquid level. The acceleration and deceleration constraint parameters during the robot's normal walking process are determined based on the liquid surface sloshing frequency. Based on the S-shaped speed planning method, and combined with the pre-planned walking path, the acceleration and deceleration constraint parameters, and the maximum allowable speed, the speed curve corresponding to the walking path is generated. The robot is controlled to walk along the walking path based on the speed curve.

2. The robot walking control method according to claim 1, characterized in that, The step of controlling the robot to walk along the walking path according to the speed curve includes: If the walking path has at least one turning segment, and the estimated speed of the robot when it walks to the turning segment is greater than the maximum turning speed allowed during the robot's normal walking process, the speed curve is updated when the robot walks a preset distance before reaching the turning segment, and the robot is controlled to walk along the walking path according to the updated speed curve. Wherein, a continuous turning section is one turning section; the updated speed curve is used to: decelerate the robot when it travels a preset distance before the turning section, reduce the robot's speed when it travels to the turning section to the maximum turning speed, and accelerate the robot to the speed before deceleration after passing the turning section.

3. The robot walking control method according to claim 2, characterized in that, The formula for calculating the maximum permissible turning speed during the robot's normal walking process is as follows: in, For the maximum permissible turning speed, The unit is m / s. For the maximum permissible centripetal acceleration, The unit is m / s 2 , The radius of the turning section. The unit is m; The formula for calculating the maximum permissible centripetal acceleration is: in, It is the acceleration due to gravity. The value is m / s 2 , The value is 9.81 m / s 2 , This refers to the remaining height inside the container. The unit is m. Let be the inner radius of the container. The unit is m.

4. The robot walking control method according to any one of claims 1 to 3, characterized in that, The acceleration / deceleration constraint parameters include at least one of the following: upper limit of acceleration, upper limit of deceleration, upper limit of rate of change of acceleration, and upper limit of rate of change of deceleration. The step of determining the acceleration and deceleration constraint parameters during the robot's normal walking process based on the liquid surface sloshing frequency includes: The upper limit of acceleration during the robot's normal walking process is determined based on the frequency of liquid surface sloshing. And / or, determine the upper limit of deceleration during the robot's normal walking process based on the liquid surface sloshing frequency; And / or, determine the upper limit of the rate of change of acceleration during the robot's normal walking process based on the liquid surface sloshing frequency; And / or, determine the upper limit of the rate of change of deceleration during the robot's normal walking process based on the liquid surface sloshing frequency.

5. The robot walking control method according to claim 4, characterized in that, The formula for calculating the upper limit of acceleration is: in, The upper limit of acceleration, The unit is m / s 2 , For safety reasons, The value is 0.

7. The frequency of liquid surface sloshing. The unit is Hz. The maximum allowable sway amplitude, The value is 0.005m; The formula for calculating the upper limit of deceleration is: in, The upper limit of deceleration, The unit is m / s 2 ; set up For the maximum permissible speed, The unit is m / s. , For a pre-set safe distance, The unit is m. , This is the margin distance. The value ranges from 0.1m to 0.3m. The maximum speed is the chassis's rated speed. The unit is m / s; Less than hour, ; Greater than or equal to hour, .

6. The robot walking control method according to any one of claims 1 to 3, characterized in that, The formula for calculating the liquid surface sloshing frequency is: in, The frequency of liquid surface sloshing. The unit is Hz. The value is 3.

14. It is the acceleration due to gravity. The value is 9.81 m / s 2 , Let be the inner radius of the container. The unit is m. The liquid level inside the container. The unit is m.

7. The robot walking control method according to any one of claims 1 to 3, characterized in that, The mobile chassis includes a chassis body and wheels. The wheels are connected to the chassis body via an active suspension structure. A vertical acceleration sensor is installed on the chassis body to detect the vertical acceleration of the chassis body. The robot walking control method is executed by the main control module. During the robot's walking along the walking path, the main control module periodically acquires the vertical acceleration of the chassis body. When the absolute value of the vertical acceleration is greater than or equal to a first set value, the main control module controls the damping of the active suspension structure to increase from the preset basic damping to the first set damping. When the absolute value of the vertical acceleration is less than or equal to a second set value for a continuous set time, the main control module controls the damping of the active suspension structure to return to the preset basic damping.

8. The robot walking control method according to any one of claims 1 to 3, characterized in that, Before obtaining the inner radius of the container and the liquid level inside the container, the method further includes: In response to a container containing liquid being placed on the tray, a first total weight of the container and the liquid inside the container is obtained; After controlling the robot to walk along the walking path according to the speed curve, the method further includes: After the robot walks to the end of the walking path, the second total weight of the container and the liquid inside the container is obtained; The difference between the first total weight and the second total weight is taken as the liquid loss. The liquid surface sloshing frequency, the acceleration / deceleration constraint parameters, and the liquid loss amount are recorded as historical delivery data.

9. A robot walking control system, characterized in that, It includes a main control module, which is used to execute the robot walking control method according to any one of claims 1 to 8.

10. A robot, characterized in that, Includes the robot walking control system as described in claim 9.

Images