Control method and device of freight robot, freight robot

Abstract

The present application relates to a control method and device for a freight robot, and a freight robot, wherein the freight robot comprises: a mechanical trunk and mechanical arms installed on both sides of the mechanical trunk, the mechanical arms are used to carry goods; a pair of mechanical legs arranged side by side, the mechanical legs comprising a first support arm, a second support arm and a support rod, the upper end of the first support arm is connected to the lower end of the mechanical trunk through a first joint, the upper end of the second support arm is connected to the lower end of the first support arm through a connecting structure, the lower end of the second support arm is equipped with a first moving wheel, the upper end of the support rod is connected to the second support arm, the lower end of the support rod is equipped with a second moving wheel and the support rod is shorter than the second support arm; wherein the connecting structure can adjust the angle between the first support arm and the second support arm, a preset angle can be formed between the support rod and the second support arm, and the geometric centers of the first support arm, the second support arm and the support rod are coplanar.

Description

Technical Field

[0001] The present application relates to the field of AGV, and in particular to a control method and device for a freight robot, and a freight robot. Background Art

[0002] The humanoid AGV (automatic guided vehicle) can be called a freight robot. Compared with traditional AGVs, freight robots occupy less horizontal area due to their standing structure; and freight robots use arm structures to complete loading and unloading, which is more flexible and convenient. In a freight robot, moving wheels are installed at the bottom of the supporting legs, and the movement of the freight robot is achieved by driving the moving wheels to roll. Since the freight robot is humanoid, its two supporting legs and the corresponding two moving wheels are arranged side by side, and the freight robot has only one contact point with the ground in its own moving direction. Therefore, the freight robot needs to maintain its center of gravity directly above the moving wheels to ensure that it does not tip over (forward or backward). However, the center of gravity of the freight robot will jump when loading and unloading goods. Due to the rapid change of the center of gravity, it is difficult for the freight robot to adjust its posture in time to maintain its center of gravity directly above the moving wheels, and the freight robot is prone to tipping over when loading and unloading goods.

[0003] There is currently no effective solution to the problem that freight robots are prone to tipping over when loading and unloading cargo. Summary of the invention

[0004] The present invention provides a control method and device for a freight robot and a freight robot to solve the problem that the current freight robot is prone to tipping over when loading and unloading goods.

[0005] In a first aspect, the present invention provides a freight robot, comprising:

[0006] A mechanical trunk and mechanical arms mounted on both sides of the mechanical trunk, the mechanical arms are used to carry cargo;

[0007] A pair of mechanical legs arranged side by side, the mechanical legs comprising a first support arm, a second support arm and a support rod, the upper end of the first support arm is connected to the lower end of the mechanical trunk through a first joint, the upper end of the second support arm is connected to the lower end of the first support arm through a connecting structure, the lower end of the second support arm is equipped with a first moving wheel, the upper end of the support rod is connected to the second support arm, the lower end of the support rod is equipped with a second moving wheel and the support rod is shorter than the second support arm;

[0008] Among them, the connecting structure can adjust the angle between the first support arm and the second support arm, a preset angle can be formed between the support rod and the second support arm, and the geometric centers of the first support arm, the second support arm and the support rod are coplanar.

[0009] In a second aspect, the present invention provides a control method for a freight robot, which is applied to the controller of the freight robot described in the first aspect and includes:

[0010] Before the freight robot is loaded with goods, under the premise of keeping the center of gravity of the freight robot directly above the first moving wheel and forming a preset angle between the support rod and the second support arm, the freight robot is controlled to perform a squatting action until the second moving wheel contacts the ground, and the freight robot is continuously controlled to perform a center of gravity adjustment action until the center of gravity of the freight robot is between the first moving wheel and the second moving wheel;

[0011] Among them, the squatting action and the center of gravity adjustment action of the freight robot both include adjusting the angle between the mechanical trunk and the first support arm and adjusting the angle between the first support arm and the second support arm.

[0012] In a third aspect, the present invention provides a control device for a freight robot, which is applied to the controller of the freight robot described in the first aspect and includes:

[0013] The first control module is used to control the freight robot to keep standing when the freight robot is moving without load;

[0014] The second control module is used for controlling the freight robot to perform a squatting action until the second moving wheel contacts the ground, and continuing to control the freight robot to perform a center of gravity adjustment action until the center of gravity of the freight robot is between the first moving wheel and the second moving wheel, under the premise that the center of gravity of the freight robot is kept directly above the first moving wheel and a preset angle is formed between the support rod and the second support arm before the freight robot is loaded with goods;

[0015] Among them, the squatting action and the center of gravity adjustment action of the freight robot both include adjusting the angle between the mechanical trunk and the first support arm and adjusting the angle between the first support arm and the second support arm.

[0016] Compared with the related art, the present invention adds a support rod to the second support arm at the bottom of the mechanical legs, and the support rod can assist in supporting the mechanical trunk of the freight robot after the freight robot performs a squatting action. The freight robot in the present invention can allow the center of gravity to jump to a certain extent, while the conventional freight robot will tip over as long as the center of gravity is not directly above the moving wheels. This shows that the present invention greatly improves the support stability of the freight robot when loading and unloading goods, and solves the problem that the current freight robot is prone to tipping over when loading and unloading goods.

[0017] Details of one or more embodiments of the present application are set forth in the following drawings and description to make other features, objects, and advantages of the present application more readily apparent. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] Figure 1 is a schematic diagram of a freight robot squatting in the first embodiment;

[0019] Figure 2 is a standing schematic diagram of the freight robot provided in the first embodiment of the present invention;

[0020] Figure 3 is a schematic diagram of the mechanical legs of the freight robot provided in the first embodiment of the present invention;

[0021] Figure 4 is a schematic diagram of a freight robot squatting in the second embodiment of the present invention;

[0022] Figure 5 is a standing diagram of the freight robot provided in the second embodiment of the present invention Figure 1 ;

[0023] Figure 6 is a standing diagram of the freight robot provided in the second embodiment of the present invention Figure 2 . DETAILED DESCRIPTION

[0024] In order to more clearly understand the purpose, technical solutions and advantages of the present application, the present application is described and illustrated below in conjunction with the accompanying drawings and embodiments.

[0025] Unless otherwise defined, the technical terms or scientific terms involved in this application shall have the general meaning understood by people with general skills in the technical field to which this application belongs. The words "one", "a", "the", "these" and the like in this application do not indicate a quantitative limitation, and they may be singular or plural. The terms "include", "comprise", "have" and any variants thereof involved in this application are intended to cover non-exclusive inclusions; for example, a process, method and system, product or device comprising a series of steps or modules (units) is not limited to the listed steps or modules (units), but may include unlisted steps or modules (units), or may include other steps or modules (units) inherent to these processes, methods, products or devices. The words "connect", "connected", "coupled" and the like involved in this application are not limited to physical or mechanical connections, but may include electrical connections, whether direct or indirect. The "multiple" involved in this application refers to two or more. "And / or" describes the association relationship of associated objects, indicating that there may be three relationships, for example, "A and / or B" may mean: A exists alone, A and B exist at the same time, and B exists alone. Generally, the character " / " indicates that the objects associated with each other are in an "or" relationship. The terms "first", "second", "third", etc. in this application are only used to distinguish similar objects and do not represent a specific ordering of the objects.

[0026] The control method and device of the freight robot and the freight robot provided by the present invention are specifically described below through some embodiments.

[0027] Reference Figure 1 and Figure 2 In the first embodiment, the freight robot is a humanoid robot and includes: a mechanical trunk 10 and mechanical arms 20 installed on both sides of the mechanical trunk 10, the mechanical arms 20 are used to carry goods; a pair of mechanical legs arranged side by side, the mechanical legs include a first support arm 31, a second support arm 32 and a support rod 33, the upper end of the first support arm 31 is connected to the lower end of the mechanical trunk 10 through a first joint 41, the upper end of the second support arm 32 is connected to the lower end of the first support arm 31 through a connecting structure, the lower end of the second support arm 32 is equipped with a first moving wheel 34, the upper end of the support rod 33 is connected to the second support arm 32, the lower end of the support rod 33 is equipped with a second moving wheel 35 and the support rod 33 is shorter than the second support arm 32; wherein the connecting structure can adjust the angle between the first support arm 31 and the second support arm 32, a preset angle can be formed between the support rod 33 and the second support arm 32, and the geometric centers of the first support arm 31, the second support arm 32 and the support rod 33 are coplanar.

[0028] Reference Figure 3 Further, in the first embodiment, the connection structure is the fourth joint 44, and the lower end of the first support arm 31 is connected to the upper end of the second support arm 32 through the fourth joint 44. Then the mechanical support leg in this embodiment is composed of two end support arms. Figures 4 to 6 Correspondingly, in the second embodiment, the connection structure includes a third support arm 36, the upper end of the third support arm 36 is connected to the lower end of the first support arm 31 through a second joint 42, and the lower end of the third support arm 36 is connected to the upper end of the second support arm 32 through a third joint 43. The main part of the mechanical leg in this embodiment is composed of three-end support arms.

[0029] In both the first embodiment and the second embodiment, the angle between the two corresponding parts can be adjusted by moving each joint, so as to realize the squatting and standing movements and the center of gravity adjustment movement of the freight robot. Among them, the first joint 41, the second joint 42, the third joint 43 and the fourth joint 44 are all electric joints, so that each joint can be automatically controlled. The rotation axes of the first joint 41, the second joint 42, the third joint 43 and the fourth joint 44 are parallel to each other to ensure that during the rotation process, the geometric centers of the first support arm 31, the second support arm 32 and the support rod 33 are always coplanar.

[0030] It can be seen from the above two embodiments that, compared with conventional freight robots, the present invention adds a support rod 33 on the second support arm 32 at the bottom of the mechanical leg, and the support rod 33 can assist in supporting the mechanical trunk 10 of the freight robot after the freight robot performs a squatting action. Specifically, when the freight robot is in an unloaded state, it is in a standing state, and the angle between two adjacent components tends to 180° (for example, the angle between the mechanical trunk 10 and the first support arm 31 tends to 180°). At this time, the center of gravity of the freight robot is directly above the first moving wheel 34, and the freight robot can maintain standing balance. When the freight robot needs to load goods, it can first perform a squatting action, which is the same as a human squatting. The angle between the two adjacent components in the freight robot becomes smaller and the directions of the two adjacent angles are opposite. For example, in this embodiment, the angle between the first support arm 31 and the second support arm 32 is opposite to the angle between the first support arm 31 and the mechanical trunk 10. It should be noted that, during the squatting process, the second support arm 32 should be controlled to tilt toward the side where the support rod 33 is installed. As the tilt angle increases, the second moving wheel 35 on the support rod 33 will contact the ground, so that a triangular structure is formed between the support rod 33, the second support arm 32 and the ground, and the center of gravity of the freight robot can be adjusted to between the two moving wheels. At this time, the freight robot contacts the ground at two points with a gap in its own moving direction, and the center of gravity is between the two contact points. Even if the center of gravity of the freight robot jumps during the loading and unloading process, as long as the center of gravity is still between the two moving wheels, the freight robot will not fall over. Therefore, the freight robot in the above embodiment can allow the center of gravity to jump to a certain extent, while the conventional freight robot will fall over as long as the center of gravity is not directly above the moving wheels, which shows that the present invention greatly improves the support stability of the freight robot during loading and unloading, and solves the problem that the current freight robot is prone to falling over during loading and unloading.

[0031] In the present invention, there are two connection modes between the support rod 33 and the second support arm 32. One is that the upper end of the support rod 33 is fixedly connected to the second support arm 32 and the angle between the support rod 33 and the second support arm 32 is a preset angle. Instead, the upper end of the support rod 33 is connected to the middle part of the second support arm 32 through the fifth joint, and the middle part of the second support arm 32 is provided with a receiving groove for accommodating the support rod 33. The rotation range of the fifth joint allows the support rod 33 to rotate into the receiving groove and form a preset angle between the support rod 33 and the second support arm 32. Among them, the fifth joint adopts an electric joint, and the axes of the fifth joint and the first joint 41 are parallel. When the freight robot needs to load goods, the angle between the support rod 33 and the second support arm 32 can be increased by controlling the fifth joint until it becomes a preset angle. When the freight robot is unloaded, the angle between the support rod 33 and the second support arm 32 can be reduced by controlling the fifth joint until the support rod 33 enters the receiving groove. It should be noted that when the freight robot is loading goods, the angle between the support rod 33 and the second support arm 32 tends to increase under pressure, so a corresponding limit can be set to prevent the motor in the fifth joint from generating a large torque. Of course, the angle can also be locked by only the joint itself.

[0032] It can be seen from the above description that when the first moving wheel 34 and the second moving wheel 35 can form a larger interval, the freight robot can allow a greater degree of center of gravity jump. Therefore, in this embodiment, the preset angle is an obtuse angle, and the upper end of the support rod 33 is connected to the upper part of the second support arm 32. The preset angle can be 100° or 120°, etc. Compared to the embodiment in which the preset angle is set to an acute angle or the upper end of the support rod 33 is connected to the lower part of the second support arm 32, this embodiment can form a larger interval between the first moving wheel 34 and the second moving wheel 35, so that the freight robot has higher support stability, which solves the problem that the existing freight robot is prone to tipping over when loading and unloading goods.

[0033] As mentioned above, the physical structure and main working principle of the freight robot are mainly described. As follows, the working process of the freight robot in the first embodiment is specifically described in combination with the control method of the freight robot.

[0034] In the first embodiment, the control method of the freight robot includes: when the freight robot moves empty, controlling the freight robot to maintain a standing state; before the freight robot loads the cargo, on the premise that the center of gravity of the freight robot is kept directly above the first moving wheel 34 and a preset angle is formed between the support rod 33 and the second support arm 32, controlling the freight robot to perform a squatting action until the second moving wheel 35 contacts the ground, and continuing to control the freight robot to perform a center of gravity adjustment action until the center of gravity of the freight robot is between the first moving wheel 34 and the second moving wheel 35; after the freight robot unloads the cargo, controlling the freight robot to perform a center of gravity adjustment action until the center of gravity of the freight robot is directly above the first moving wheel 34, and continuing to control the freight robot to perform a standing action until the freight robot is in a standing state on the premise that the center of gravity of the freight robot is kept directly above the first moving wheel 34. Among them, the squatting action, the center of gravity adjustment action and the standing action of the freight robot all include adjusting the angle between the mechanical torso 10 and the first support arm 31 and adjusting the angle between the first support arm 31 and the second support arm 32.

[0035] In the unloaded state, the freight robot maintains a standing state, that is, the angle between two adjacent parts tends to 180° (for example, the angle between the mechanical trunk 10 and the first support arm 31 tends to 180°). At this time, the center of gravity of the freight robot is directly above the first moving wheel 34, and the freight robot can maintain a standing balance. The freight robot mainly carries goods through the mechanical arm 20. When the goods are placed on the mechanical arm 20, the center of gravity of the freight robot will move forward instantly. The freight robot has only a single point of contact with the ground in the moving direction, so a slight forward movement of the center of gravity of the freight robot will easily cause the freight robot to tilt forward.

[0036] Therefore, the control method in this embodiment controls the freight robot to perform a squatting action before loading the cargo. Similar to a human squatting, the angle between two adjacent parts of the freight robot becomes smaller and the directions of the two adjacent angles are opposite. For example, in this embodiment, the angle between the first support arm 31 and the second support arm 32 is opposite to the angle between the first support arm 31 and the mechanical trunk 10. That is, a relative inclination in the opposite direction is generated between the two connected parts. For example, referring to Figure 1 In this embodiment, when the freight robot squats, the first support arm 31 tilts backward, the second support arm 32 tilts forward, and the mechanical trunk 10 remains upright (relative to the first support rod 33, which tilts forward), so that the connected components tilt in opposite directions. It should be noted that during the squatting process, the second support arm 32 should be controlled to tilt toward the side where the support rod 33 is installed.

[0037] Furthermore, during the squatting process, the center of gravity of the freight robot needs to be kept directly above the first moving wheel 34. The center of gravity of the freight robot is mainly related to the inclination angle of each component. Figure 1 When the first support arm 31 tilts backward, the center of gravity of the freight robot will move backward, and when the second support arm 32 tilts forward, the end point of the freight robot will shift forward. Therefore, by controlling each joint to adjust the tilt relationship (or angle) between adjacent components, the center of gravity of the freight robot can be controlled. During the squatting process, the center of gravity of the freight robot can be maintained directly above the first moving wheel 34. For example, when the center of gravity shifts forward, the speed at which the first support rod 33 tilts backward can be increased or the speed at which the second support arm 32 tilts forward can be reduced to move the center of gravity of the freight robot backward. Specifically, a PID control algorithm can be used to control each joint in real time. Continue to refer to Figure 1 When it is necessary to adjust the center of gravity of the freight robot to between the first moving wheel 34 and the second moving wheel 35, the first support arm 31 can be controlled to tilt forward so that the center of gravity of the freight robot moves forward until it is between the two moving wheels.

[0038] As described above, some specific examples are used to illustrate how the squatting action and the center of gravity adjustment action of the freight robot are specifically implemented. The standing action of the freight robot is the opposite of the squatting action.

[0039] It can be seen from the above description that when the control method provided in the first embodiment is used to control the freight robot, the freight robot can maintain a high supporting stability when loading and unloading goods, thereby solving the problem that the existing freight robots are prone to tipping over when loading and unloading goods.

[0040] In the first embodiment, a control device for a freight robot is also provided, and the control method for acquiring the robot in the first embodiment is used to implement the control method for acquiring the robot, which has been described and will not be repeated. The terms "module", "unit", "subunit", etc. used below can implement a combination of software and / or hardware for a predetermined function. Although the devices described in the following embodiments are preferably implemented in software, the implementation of hardware, or a combination of software and hardware, is also possible and conceivable.

[0041] The control device of the freight robot in the first embodiment includes a first control module, a second control module and a third control module.

[0042] The first control module is used to control the freight robot to keep standing when the freight robot moves without load.

[0043] The second control module is used to control the freight robot to perform a squatting action until the second moving wheel contacts the ground before the freight robot is loaded with goods, under the premise of keeping the center of gravity of the freight robot directly above the first moving wheel and forming a preset angle between the support rod and the second support arm, and continue to control the freight robot to perform a center of gravity adjustment action until the center of gravity of the freight robot is between the first moving wheel and the second moving wheel.

[0044] The third control module is used to control the freight robot to perform a center of gravity adjustment action after unloading the cargo until the center of gravity of the freight robot is directly above the first moving wheel, and continue to control the freight robot to perform a standing action while keeping the center of gravity of the freight robot directly above the first moving wheel until the freight robot is in a standing state.

[0045] Among them, the squatting action, the center of gravity adjustment action and the standing action of the freight robot all include adjusting the angle between the mechanical torso and the first support arm and adjusting the angle between the first support arm and the second support arm.

[0046] It should be noted that the above modules can be functional modules or program modules, and can be implemented by software or hardware. For modules implemented by hardware, the above modules can be located in the same processor; or the above modules can be located in different processors in any combination.

[0047] It should be understood that the specific embodiments described herein are only used to explain the application, rather than to limit it. Based on the embodiments provided in this application, all other embodiments obtained by ordinary technicians in this field without creative work are within the protection scope of this application.

[0048] Obviously, the drawings are only some examples or embodiments of the present application. For ordinary technicians in the field, the present application can also be applied to other similar situations based on these drawings without creative work. In addition, it is understandable that although the work done in this development process may be complicated and lengthy, for ordinary technicians in the field, certain changes in design, manufacturing or production based on the technical content disclosed in this application are only conventional technical means and should not be regarded as insufficient content disclosed in this application.

Claims

1. A freight robot, characterized in that: include: A mechanical trunk and mechanical arms mounted on both sides of the mechanical trunk, the mechanical arms are used to carry cargo; A pair of mechanical legs arranged side by side, the mechanical legs comprising a first support arm, a second support arm and a support rod, the upper end of the first support arm is connected to the lower end of the mechanical trunk through a first joint, the upper end of the second support arm is connected to the lower end of the first support arm through a connecting structure, the lower end of the second support arm is equipped with a first moving wheel, the upper end of the support rod is connected to the second support arm, the lower end of the support rod is equipped with a second moving wheel and the support rod is shorter than the second support arm; Among them, the connecting structure can adjust the angle between the first support arm and the second support arm, a preset angle can be formed between the support rod and the second support arm, and the geometric centers of the first support arm, the second support arm and the support rod are coplanar; the connecting structure includes a third support arm, the upper end of the third support arm is connected to the lower end of the first support arm through a second joint, and the lower end of the third support arm is connected to the upper end of the second support arm through a third joint.

2. The freight robot according to claim 1, characterized in that: The upper end of the support rod is fixedly connected to the second support arm, and the angle between the support rod and the second support arm is a preset angle.

3. The freight robot according to claim 1, characterized in that: The upper end of the support rod is connected to the middle part of the second support arm through the fifth joint. The middle part of the second support arm is provided with a receiving groove for accommodating the support rod. The rotation range of the fifth joint allows the support rod to rotate into the receiving groove and form a preset angle between the support rod and the second support arm.

4. The freight robot according to claim 1, characterized in that: The default angle is an obtuse angle.

5. The freight robot according to claim 1, characterized in that: The upper end of the support rod is connected to the upper part of the second support arm.

6. A method for controlling a freight robot, characterized in that: A controller for a freight robot according to any one of claims 1 to 5, comprising: Before the freight robot is loaded with goods, under the premise of keeping the center of gravity of the freight robot directly above the first moving wheel and forming a preset angle between the support rod and the second support arm, the freight robot is controlled to perform a squatting action until the second moving wheel contacts the ground, and the freight robot is continuously controlled to perform a center of gravity adjustment action until the center of gravity of the freight robot is between the first moving wheel and the second moving wheel; Among them, the squatting action and the center of gravity adjustment action of the freight robot both include adjusting the angle between the mechanical trunk and the first support arm and adjusting the angle between the first support arm and the second support arm.

7. The robot control method according to claim 6, characterized in that: Also includes: After the freight robot unloads the cargo, the freight robot is controlled to perform a gravity adjustment action until the gravity center of the freight robot is directly above the first moving wheel, and the freight robot is controlled to perform a standing action while maintaining the gravity center of the freight robot directly above the first moving wheel until the freight robot is in a standing state; Among them, the standing action of the freight robot includes adjusting the angle between the mechanical trunk and the first support arm and adjusting the angle between the first support arm and the second support arm.

8. A control device for a freight robot, characterized in that: A controller for a freight robot according to any one of claims 1 to 5, comprising: The first control module is used to control the freight robot to keep standing when the freight robot is moving without load; The second control module is used for controlling the freight robot to perform a squatting action until the second moving wheel contacts the ground, and continuing to control the freight robot to perform a center of gravity adjustment action until the center of gravity of the freight robot is between the first moving wheel and the second moving wheel, under the premise that the center of gravity of the freight robot is kept directly above the first moving wheel and a preset angle is formed between the support rod and the second support arm before the freight robot is loaded with goods; Among them, the squatting action and the center of gravity adjustment action of the freight robot both include adjusting the angle between the mechanical trunk and the first support arm and adjusting the angle between the first support arm and the second support arm.

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