Automatic telescopic mechanism and wheel arm humanoid robot

Abstract

The invention discloses an automatic telescopic mechanism and a wheel arm humanoid robot, and belongs to the technical field of specialized robots. The moving assembly can stretch up and down relative to the fixed assembly; the driving assembly is used for driving the moving assembly to stretch up and down; the fixing assembly comprises a first-stage fixing pipe; the movement assembly comprises a secondary stroke pipe; the second-stage stroke pipe is provided with a first inner space with one open end, and the upper part of the first-stage fixed pipe is arranged in the first inner space; the driving assembly is arranged on the top of the first-stage fixing pipe and drives the second-stage stroke pipe to stretch out and draw back in the length direction of the first-stage fixing pipe. According to the automatic telescopic mechanism and the wheel-arm humanoid robot, the problems that in the prior art, due to a vertical mast and a lifting bracket of a telescopic structure of a wheel-arm robot and a driving structure adopting a belt type or chain type transmission mode, the whole structure is complex, the size is large, and maintenance is not easy can be effectively solved; and transportation and storage of the wheel-arm robot are not convenient.

Description

TECHNICAL FIELD

[0001] The present application belongs to the technical field of special robots. BACKGROUND

[0002] In the field of wheel-arm robots, as a composite robot deeply integrated with a wheeled mobile platform and a mechanical arm, the wheel-arm robot combines efficient mobile capability with flexible operation capability to realize the integration of "mobility + operation", and is widely used in many fields such as industrial manufacturing, industrial logistics, home service and emergency rescue.

[0003] In the related technology of wheel-arm robots, the composition of the wheeled mobile platform usually includes a movable base, a vertical mast attached to the base, and a lifting carriage coupled to the vertical mast. The mechanical arm is coupled to the lifting carriage and is driven by the lifting carriage to move in the vertical direction. However, in the prior art, the vertical mast and the lifting carriage generally adopt a belt or chain transmission mode to realize driving, and at the same time, the vertical mast itself does not have a telescopic function. This causes two problems: on the one hand, the height of the vertical mast is fixed and cannot be changed, which is not convenient for transportation and storage of the wheel-arm robot; on the other hand, the belt or chain transmission structure is relatively complex, which increases the complexity of the overall structure of the wheel-arm robot, the overall volume is large and the weight is heavy.

[0004] Therefore, it is an urgent problem in the current field to design a telescopic mechanism with variable height to replace the existing vertical mast and lifting carriage to simplify the structure of the wheel-arm robot. SUMMARY

[0005] The purpose of the present application is to provide an automatic telescopic mechanism and a wheel-arm humanoid robot to solve the problems of the prior art, such as the complex overall structure, large volume, and inconvenient transportation and storage of the wheel-arm robot caused by the telescopic structure of the vertical mast and the lifting carriage and the belt or chain transmission mode of the driving structure. In order to achieve the above purpose, the present application provides the following technical solutions: An automatic telescopic mechanism, comprising a driving assembly, a moving assembly and a fixed assembly; the moving assembly is telescopic up and down relative to the fixed assembly; the driving assembly is used to drive the moving assembly to telescope up and down; the fixed assembly comprises a primary fixed tube; the moving assembly comprises a secondary stroke tube; the secondary stroke tube has a first internal space with one end open, and the upper part of the primary fixed tube is arranged in the first internal space; the driving assembly is arranged at the top of the primary fixed tube and drives the secondary stroke tube to telescope along the length direction of the primary fixed tube.

[0006] Further, the driving assembly comprises a motor; a rotating disc is fixed on an output shaft of the motor; a plurality of swing shafts are arranged on the rotating disc; the swing shafts are evenly arranged along the circumference of the rotating disc; the motor drives the swing shafts to rotate, so that pressure is generated on the inner wall of the secondary stroke pipe, and the secondary stroke pipe is driven to elongate relative to the primary fixed pipe.

[0007] Further, one end of the swing shaft is hinged to the rotating disc, the swing shaft naturally swings downward under the action of gravity, and the other end of the swing shaft is provided with a ball mounting groove; a ball is rotatably connected in the ball mounting groove; part of the outer wall of the ball is always in contact with the inner wall of the secondary stroke pipe. Further, the outer wall of the secondary stroke pipe is provided with a guide; the bottom outer wall of the primary fixed pipe is provided with a vertical sliding rail; the guide cooperates with the sliding rail to guide the expansion and contraction of the secondary stroke pipe.

[0008] Further, a second internal space is arranged in the primary fixed pipe; a power supply is arranged in the second internal space, and is used for supplying power to the motor; the power supply is a wired power supply or a battery; the battery is a dry battery or a storage battery.

[0009] Further, a power supply cover is arranged at the bottom of the primary fixed pipe; the power supply cover encloses the second internal space; one side of the power supply cover close to the second internal space is provided with a spring.

[0010] Further, a speed changer is arranged between the output shaft of the motor and the rotating disc, and is used for adjusting the rotating speed of the output shaft of the motor and then transmitting the rotating speed to the rotating disc.

[0011] Further, the inner diameter of the secondary stroke pipe gradually changes from top to bottom, the slope k of the curve of the inner wall satisfies k>0, and the movement of the secondary stroke pipe can be controlled under the condition that the rotating speed of the motor is fixed.

[0012] Further, a controller is further included, the rotating speed of the rotating disc is controlled by controlling the motor and the speed changer, and the expansion and contraction movement of the secondary stroke pipe relative to the primary fixed pipe and the hovering at a predetermined position are realized.

[0013] A wheel arm humanoid robot comprising the automatic telescopic mechanism.

[0014] The beneficial effects of the present application are: The application discloses an automatic telescopic mechanism and a wheel-arm humanoid robot, a driving unit is arranged in a secondary stroke pipe, the driving unit drives a swing shaft and a ball to rotate, the swing shaft and the ball are used to drive the linear motion of the secondary stroke pipe by the component force of the pressure generated by the rotation of the swing shaft and the ball on the pipe wall of the secondary stroke pipe, the rotation is converted into the linear motion, and the telescopic mechanism of the secondary stroke pipe relative to a primary fixed pipe is realized. The automatic telescopic mechanism is used for replacing the vertical mast of a wheel-type mobile platform of an existing wheel-arm robot, the structure of the wheel-type mobile platform is simplified, the cost is reduced, maintenance is easy, and the wheel-arm robot is convenient to store and transport. BRIEF DESCRIPTION OF DRAWINGS

[0015] Figure 1 is a front view of the overall structure of the application; Figure 2 is a sectional view along the direction of H-H in the application Figure 1 Figure 3 is an enlarged view of IV in the application Figure 2 Figure 4 is a top view of the swing shaft and the rotating disc in the application Figure 5 is a force analysis diagram of the contact points between the ball and the inner wall of the secondary stroke pipe in the application In the drawings: 1, primary fixed pipe; 2, motor; 3, rotating disc; 4, swing shaft; 5, secondary stroke pipe; 6, power supply; 7, power supply cover; 8, ball. DETAILED DESCRIPTION

[0016] The application will be further described in detail below in combination with the drawings and specific embodiments, but the application is not limited to the following embodiments.

[0017] In the description of the application, it should be understood that the terms "center", "longitudinal", "transverse", "length", "width", "thickness", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", "clockwise", "counterclockwise", "axial", "radial", "circumferential" and the like indicate the orientation or positional relationship based on the orientation or positional relationship shown in the drawings, and are only for the convenience of describing the application and simplifying the description, and therefore cannot be understood as indicating or implying that the devices or elements referred to must have a particular orientation, be constructed and operated in a particular orientation, and therefore cannot be understood as limiting the application.

[0018] In the description of the application, "first feature" and "second feature" can include one or more features.

[0019] In the description of the application, "a plurality of" means two or more.

[0020] ​​In the description of the application, the first feature is "on", "above", or "over" the second feature can include the first and second features are in direct contact, but also can include the first and second features are not in direct contact but through the additional features between them in contact.

[0021] In the description of the application, the first feature is "on", "above", and "over" the second feature includes the first feature is directly above and obliquely above the second feature, or just means that the first feature is higher than the second feature in height.

[0022] In the description of the application, the description of the reference terms "one embodiment", "some embodiments", "illustrative embodiment", "example", "specific example", "some examples" and the like means that the specific features, structures, materials or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the application. In this specification, the illustrative description of the above terms does not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described can be combined in any one or more embodiments or examples in a suitable manner.

[0023] Embodiment 1 See attached Figures 1 to 5 The embodiment discloses an automatic telescopic mechanism, which is composed of a driving assembly, a moving assembly and a fixed assembly. The moving assembly includes a two-stage stroke pipe 5 with a first internal space open at one end. The fixed assembly includes a one-stage fixed pipe 1, the upper part of which is arranged in the first internal space, and the two-stage stroke pipe 5 is driven to extend and retract relative to the one-stage fixed pipe 1 by the driving assembly. The driving assembly includes a motor 2 arranged at the top of the one-stage fixed pipe 1, and the one-stage fixed pipe 1 has a second internal space in which a power supply 6 is arranged and capable of supplying power to the motor 2. The output shaft of the motor 2 is fixedly connected with the rotating shaft of a rotating disc 3, so as to drive the rotating disc 3 to rotate. A plurality of swing shafts 4 are uniformly distributed along the circumference of the rotating disc 3, each swing shaft 4 of the plurality of swing shafts 4 is hingedly connected with the rotating disc 3 at one end and rotationally connected with a ball 8 at the other end. In the process of driving the swing shaft 4 to rotate with the rotating disc 3 by the motor 2, part of the outer wall of the ball 8 always maintains a state of contact with the inner wall of the two-stage stroke pipe 5.

[0024] In one embodiment, the plurality of swing shafts 4 includes 2-6 swing shafts 4 uniformly arranged along the circumference of the rotating disc 3. In one example, as shown in the drawings, the plurality of swing shafts 4 includes 4 swing shafts 4. Figure 4As shown, when viewed from above, the three swing shafts 4 are evenly distributed in the circumferential direction of the rotating disc 3, and the balls 8 at the other end of the swing shafts 4 are in contact with the inner wall of the secondary stroke cylinder. At this time, the included angle between the two adjacent swing shafts 4 is 120°. By analogy, when the number of swing shafts 4 is two, the included angle between the two adjacent swing shafts 4 is 180°. When the number of swing shafts 4 is four, the included angle between the two adjacent swing shafts 4 is 90°. When the number of swing shafts 4 is five, the included angle between the two adjacent swing shafts 4 is 72°. When the number of swing shafts 4 is six, the included angle between the two adjacent swing shafts 4 is 60°. The more the number of swing shafts 4, the more the number of corresponding balls 8, and the greater the support force applied to the inside of the secondary stroke cylinder 5 during rotation, and the greater the resulting upward vertical component force. However, too many swing shafts 4 will increase the gravity and structural complexity of the drive assembly itself. The number of swing shafts 4 can be set according to specific circumstances to meet the extension stroke of the secondary stroke cylinder 5.

[0025] In one embodiment, the outer wall of the secondary stroke cylinder 5 can also be provided with a guide (not shown), and a vertical slide rail (not shown) can be vertically provided on the bottom outer wall of the primary fixed tube 1 or on the base of the wheeled mobile platform. The guide cooperates with the vertical slide rail to guide the extension of the secondary stroke cylinder 5. In one example, the guide and the slide rail can be provided with multiple. For example, two or more (2-4) slide rails can be provided, which are evenly distributed along the circumference of the secondary stroke cylinder 5 and arranged parallel to each other.

[0026] In one embodiment, the shape of the outer periphery of the cross section of the secondary stroke cylinder 5 in the horizontal direction can be a rectangular structure. That is, the appearance of the secondary stroke cylinder 5 is a prism, and an internal space for accommodating the primary fixed part is axially arranged in the inside of the prism.

[0027] In one embodiment, one end of the swing shaft 4 is hinged to the rotating disc 3, and the other end is provided with a ball mounting groove (not shown), and the ball 8 is rotatably arranged in the ball mounting groove, which can reduce the friction between the ball 8 and the secondary stroke cylinder 5 and reduce the loss of force.

[0028] In one embodiment, the primary fixed tube 1 includes a first segment and a second segment fixedly connected, wherein the first segment is arranged inside the secondary stroke cylinder 5 and has a second internal space for placing the power supply 6, and the second segment is arranged at the bottom of the secondary stroke cylinder 5 and has the same diameter as the secondary stroke cylinder 5. By setting the second segment to have the same outer diameter as the secondary stroke cylinder 5, the shape of the entire automatic extension mechanism can be made beautiful. At the same time, when the automatic extension mechanism is fixed to the base of the wheeled mobile platform of the wheel arm robot, the second segment can be fixed to the base.

[0029] The power supply 6 can be a wired power supply 6 or a battery. When the power supply 6 is a battery, the battery can be a dry battery or a storage battery. The power supply 6 is connected to the motor 2 through a circuit to supply power to the motor 2. As shown in FIG. 8, the power supply 6 is a dry battery, and a spring is arranged between the power supply 6 and the power supply cover 7. In an embodiment, the power supply cover 7 is arranged on the sidewall of the first fixed tube 1, facilitating replacement of the battery. Figure 2

[0030] In an embodiment, the drive assembly further comprises a transmission (not shown) arranged between the output shaft of the motor 2 and the rotating disc 3 in the second stroke tube 5. By arranging the transmission, the rotation speed of the output shaft of the motor 2 can be adjusted before being transmitted to the rotating shaft of the rotating disc 3.

[0031] In an embodiment, the inner diameter of the second stroke tube 5 gradually changes from top to bottom. By changing the slope of the inner wall curve of the second stroke tube 5, the movement of the second stroke tube 5 can be controlled under the condition that the rotation speed of the motor 2 is fixed. However, it should be noted that the slope (first-order differential function) k>0 of the inner wall curve of the second stroke tube 5 should be satisfied. It can be understood that the specific value of the slope can be designed according to actual needs.

[0032] In an embodiment, as shown in FIG. 9, the slope of the inner wall curve of the second stroke tube 5 remains unchanged from top to bottom, i.e., the cross section of the second stroke tube 5 is an inclined straight line. The movement control and hovering at a predetermined position of the second stroke tube 5 are achieved by controlling the rotation speed of the motor 2. Figure 2

[0033] In an embodiment, a fixing member is further arranged to lock the second stroke tube 5 and the first fixed tube 1 at a predetermined position. Specifically, when the second stroke tube 5 extends by a predetermined length relative to the first fixed tube 1, the fixing member acts between the inner wall of the second stroke tube 5 and the outer wall of the first fixed tube 1, so that the second stroke tube 5 and the first fixed tube 1 remain fixed and do not separate.

[0034] The working mode process is as follows: First, the power supply 6 can supply power to the built-in motor 2, and the controller controls the start-stop and rotation speed of the motor 2. The motor 2 rotates to provide power to drive the rotating disc 3 connected to the output shaft of the motor 2 to rotate.

[0035] Secondly, there are two or more swing shafts 4 arranged uniformly along the circumference of the rotating disc 3. The rotation of the rotating disc 3 drives the swing shafts 4 to rotate (it should be noted that the swing shafts 4 and the rotating disc 3 can rotate relative to each other, and the swing shafts 4 are in contact with the inner wall of the second stroke tube 5 under the action of gravity when stationary).

[0036] ​​Finally, the rotation of the pivot 4 will drive the secondary stroke tube 5 to move linearly. The specific working principle is as follows: Reference Figure 5 The force analysis is carried out at the contact point of the tube wall and the ball 8 (the friction between the ball 8 and the tube wall is ignored here). The tube wall is subjected to the support force N on the ball 8 and the gravity G, wherein the support force N is perpendicular to the tangent of the ball 8. The support force N can be decomposed into a horizontal component and a vertical component , wherein the horizontal component is equal in size and opposite in direction to the centripetal force of the ball 8 and the pivot 4, that is , and the vertical component is opposite in direction to the gravity G of the tube wall. It should be noted that since there are multiple balls 8, the formula here is exemplified by one of the components, and the total force F is the sum of multiple identical components . Therefore, we have:

[0037] That is:

[0038] When the total component F is greater than the gravity G of the tube wall, the tube wall will move upward, that is, it will be stretched out.

[0039] On the contrary, when the total component F is less than the gravity G of the tube wall, the tube wall will move downward, that is, it will be retracted.

[0040] When the total component F is equal to the gravity G of the tube wall, the tube wall will hover.

[0041] Wherein m is the total mass of the ball 8 and the pivot 4, in kg; ω is the angular velocity of the rotating disc 3, in rad / s; L is the length of the pivot 4, in m; R is the radius of the rotating disc 3, in m; r is the distance from the center of the ball 8 to the center axis of the rotating disc 3, in m; α is the acute angle between the support force N of the ball 8 on the tube wall and the X-axis, in °; and β is the acute angle between the pivot 4 and the Y-axis, in °.

[0042] (1) When the slope of the inner wall curve gradually changes (the rotating speed of the motor 2 is fixed) When the rotating speed of the motor 2 is fixed, ω is stable, and the size of the horizontal component is determined by the movement radius r of the ball 8 (related to the geometric position of the inner wall curve). Since the slope of the inner wall gradually changes, the tangent angle at different positions of the contact point changes, resulting in a change in the decomposition ratio of the support force N, and thus the vertical component changes dynamically with the extension and retraction position of the secondary stroke tube 5. By designing the change rule of the slope, the extension and retraction speed and direction of the stroke tube can be controlled at a fixed rotating speed.

[0043] (2) When the inner wall curve slope remains unchanged (through motor 2 speed control) At this time, the tangent angle of the contact point is fixed, The ratio of is determined by the slope (angle) Since is proportional to , the change in the speed of motor 2 will directly change , and in turn change the size of : when the speed is adjusted so that the sum of balances the gravity G, the stroke tube can hover at the predetermined position; increasing the speed so that the sum of is greater than G, the stroke tube extends upward; reducing the speed so that the sum of is less than G, the stroke tube retracts downward.

[0044] The extension and retraction movement of the secondary stroke tube 5 is essentially through the cooperation of the inner wall curve slope (which determines the force decomposition ratio) and the speed of motor 2 (which determines the centripetal force and the horizontal component size), to change the vertical component sum of multiple balls 8, and in turn adjust the vertical force of the stroke tube, to achieve extension, speed control and hovering functions.

[0045] The present application drives the secondary stroke tube 5 to move linearly in the vertical direction by using the component of the pressure on the inner wall of the secondary stroke tube 5 generated by the rotation of the balls 8; uses the centripetal force as the driving force to drive the secondary stroke tube 5, and converts the rotary motion into linear motion.

[0046] Embodiment 2 The above embodiment 1 discloses an automatic extension structure, and the present embodiment further discloses a wheel arm humanoid robot, which comprises a wheeled mobile platform, a mechanical arm and the automatic extension structure of embodiment 1, the primary fixed tube 1 of the automatic extension structure is fixed on the wheeled mobile platform, the mechanical arm is coupled to the secondary stroke tube 5, and the extension and retraction movement of the secondary stroke tube 5 is driven by the motor 2, so as to drive the mechanical arm to extend and retract or hover, replacing the vertical mast and the lifting bracket in the prior art, and in turn acting on the specified position. Simplify the structure of the extension function.

[0047] The above embodiments are only used to illustrate the technical solutions of the present application and are not limiting. Although the present application has been described in detail with reference to the preferred embodiments, it should be understood by those skilled in the art that the technical solutions of the present application can be modified or replaced equivalently without departing from the purpose and scope of the technical solutions of the present application, which should be covered in the scope of the claims of the present application. The technical, shape and structure parts not described in detail in the present application are well-known technologies.​

Claims

1. An automatic retraction mechanism characterized by: The application relates to an automatic telescopic mechanism, which comprises a driving assembly, a moving assembly and a fixed assembly; the moving assembly can be telescopically extended upwards and downwards relative to the fixed assembly; the driving assembly is used for driving the moving assembly to telescopically extend upwards and downwards; the fixed assembly comprises a primary fixed tube (1); the moving assembly comprises a secondary stroke tube (5); the secondary stroke tube (5) has a first internal space with one end being open, and the upper part of the primary fixed tube (1) is arranged in the first internal space; the driving assembly is arranged at the top of the primary fixed tube (1) and drives the secondary stroke tube (5) to telescopically extend along the length direction of the primary fixed tube (1).

2. The automatic retraction mechanism of claim 1, wherein: The driving assembly comprises a motor (2); a rotating disc (3) is fixedly arranged on the output shaft of the motor (2); a plurality of swing shafts (4) are arranged on the rotating disc (3); the swing shafts (4) are uniformly arranged along the circumferential direction of the rotating disc (3); the motor (2) drives the swing shafts (4) to rotate, so that pressure is generated on the inner wall of the secondary stroke tube (5), and the secondary stroke tube (5) is driven to extend relative to the primary fixed tube (1).

3. The self-elongating mechanism of claim 2, wherein: One end of the swing shaft (4) is hinged to the rotating disc (3), the swing shaft (4) naturally swings downwards under the action of gravity, and the other end of the swing shaft (4) is provided with a ball mounting groove; a ball (8) is rotatably connected in the ball mounting groove; part of the outer wall of the ball (8) is always in contact with the inner wall of the secondary stroke tube (5).

4. The self-elongating mechanism of claim 1, wherein: The outer wall of the secondary stroke tube (5) is provided with a guide element; the bottom outer wall of the primary fixed tube (1) is provided with a vertical sliding rail; the guide element and the sliding rail cooperate to guide the extension and contraction of the secondary stroke tube (5).

5. The self-elongating mechanism of claim 2, wherein: The primary fixed tube (1) is internally provided with a second internal space; a power supply (6) is arranged in the second internal space and is used for supplying power to the motor (2); the power supply (6) is a wired power supply (6) or a battery; the battery is a dry battery or a storage battery.

6. The automatic retraction mechanism of claim 5, wherein: The bottom of the primary fixed tube (1) is provided with a power supply cover (7); the power supply cover (7) closes the second internal space; one side of the power supply cover (7) close to the second internal space is provided with a spring.

7. The self-elongating mechanism of claim 2, wherein: A speed changer is arranged between the output shaft of the motor (2) and the rotating disc (3), and the speed changer is used for adjusting the rotating speed of the output shaft of the motor (2) and then transmitting the rotating speed to the rotating disc (3).

8. The self-elongating mechanism of claim 1, wherein: The inner diameter of the secondary stroke tube (5) gradually changes from top to bottom, the slope k of the curve of the inner wall of the secondary stroke tube (5) satisfies k>0, and the movement of the secondary stroke tube (5) can be controlled under the condition that the rotating speed of the motor (2) is fixed.

9. The automatic retraction mechanism of claim 7, wherein: A controller is further arranged, the rotating speed of the rotating disc (3) is controlled through the controller and the speed changer, the extension and contraction movement of the secondary stroke tube (5) relative to the primary fixed tube (1) and the hovering of the secondary stroke tube (5) at a predetermined position are realized.

10. A wheel-arm humanoid robot, characterized by: The automatic telescopic mechanism comprises any one of claims 1-9.

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