A flexible tensioning robot and a rod buckling deformation driving device thereof

Abstract

The present invention provides a flexible tensioning robot and a rod buckling deformation driving device thereof. The device comprises: a buckling rod, a position sensor, and a controller; a motor is respectively arranged at both ends of the buckling rod, and a nylon rope is arranged between the two motors; the position sensor is arranged at the end of the buckling rod for measuring the displacement of the buckling rod; the controller is used to receive the displacement measured by the position sensor and control the motor according to the displacement, so that the motor drives the nylon rope to contract according to the set amount. On the one hand, the device provided by the present invention has good flexibility and improves the impact resistance of the rod member, so that the tensioning robot manufactured by the device has higher impact resistance and obvious energy absorption effect; on the other hand, because the device uses fewer parts to cleverly connect key mechanisms such as the motor, buckling rod, nylon rope, and sensor, the weight of the rod structure is lighter, thereby reducing the mass and energy consumption of the robot and improving the efficiency of rolling.

Description

Technical Field

[0001] The invention relates to the technical field of flexible robots, and in particular to a flexible tensioning robot and a rod buckling deformation driving device thereof. Background Art

[0002] With the rapid development of automation and artificial intelligence technology, robots have been widely used in deep space and landing exploration. At present, most exploration robots are traditional rigid structures, such as wheeled and legged robots, which are mainly used for walking on the surface of alien planets. In recent years, flexible robots have gradually become a research hotspot, and tensegrity, as one of the flexible structures, has also been gradually applied to the field of robots. The tensegrity structure is a self-balancing structure, which includes a rod structure and a rope structure. Among them, the rod unit only bears pressure, while the rope unit only bears tension. The two forces are balanced in space to ensure the stability of the tensegrity structure. Robots based on tensegrity structures have good deformation ability, impact resistance and flexibility, so they are often used in the detection of complex terrain environments. At present, the research on tensegrity robots focuses on the field of tumbling motion, and the method of achieving tumbling motion is mostly to change the center of mass position by driving the rope length.

[0003] However, the rope drive has some disadvantages: 1) the rigid rod components have poor impact resistance and are easily damaged; 2) the rope drive device is complicated, which makes the robot heavier, with high energy consumption and low rolling efficiency. Therefore, finding a new drive structure has become an urgent problem to be solved. Summary of the invention

[0004] The present invention provides a flexible tensioning robot and a rod buckling deformation driving device thereof, which are used to solve the defects of the prior art that the rigid rod components have poor impact resistance and are easy to be damaged.

[0005] A rod buckling deformation driving device comprises: a buckling rod, a position sensor, and a controller; a motor is respectively arranged at both ends of the buckling rod, and a nylon rope is arranged between the two motors;

[0006] The position sensor is arranged at the end of the buckling rod and is used to measure the displacement of the buckling rod;

[0007] The controller is used to receive the displacement measured by the position sensor and control the motor according to the displacement, so that the motor drives the nylon rope to contract according to a set amount.

[0008] Furthermore, the rod buckling deformation driving device as described above further includes: an upper end cover, a lower end cover, and a gear shaft fixing member; the motor is fixed between the upper end cover and the lower end cover;

[0009] The gear shaft fixing part is fixed on the lower end cover, and a gear shaft that can rotate with its central axis is installed on the gear shaft fixing part, and the thread on the gear shaft is meshed with the turbine shaft of the motor; one end of the nylon rope is fixed on the gear shaft.

[0010] Furthermore, in the rod buckling deformation driving device as described above, a protrusion with a hollow structure is provided on the upper end cover; and the gear shaft and the turbine shaft are arranged inside the protrusion.

[0011] Furthermore, in the rod bending deformation driving device as described above, the cross-section of the gear shaft fixing piece is L-shaped, and its horizontal edge is located directly below the opening below the protrusion; its vertical edge is fixed to the lower end cover; and the gear shaft is installed on the horizontal edge of the gear shaft fixing piece.

[0012] Further, in the above-mentioned rod buckling deformation driving device, the upper end cover is a Y-shaped structure; the Y-shaped structure includes: a left gripping handle, a right gripping handle, and an end cover plate;

[0013] The end of the flexure rod is movably connected between the left gripping handle and the right gripping handle; the motor is installed between the end cover plate and the lower end cover.

[0014] Furthermore, the rod member buckling deformation driving device as described above comprises a circular end cover, and two protrusions are arranged on the back of the end cover, and the two protrusions are arranged horizontally between the gripping handle and the right gripping handle;

[0015] A connecting plate is fixed to the end of the flexure rod, and the connecting plate is arranged between the two protrusions. The two protrusions, the connecting plate, the left handle and the right handle are penetrated by a steel needle to achieve movable connection.

[0016] Furthermore, in the rod buckling deformation driving device as described above, a gasket is provided on the front side of the end cover.

[0017] Furthermore, in the above-mentioned rod buckling deformation driving device, the position sensor includes: a light projector and a light receiver; the light projector is fixed to the side of the protrusion, and the light receiver is fixed to the hollow protrusion of the upper end cover corresponding to the other motor.

[0018] A flexible tensioning robot comprises any one of the above-mentioned rod buckling deformation driving devices.

[0019] The flexible tensioning robot and the rod buckling deformation driving device provided by the present invention, on the one hand, can quantitatively control the bending degree of the buckled rod through the interaction between the controller and the motor and the sensor, so that the rod buckling deformation driving device provided by the present invention has good flexibility and improves the impact resistance of the rod member. Therefore, the tensioning robot manufactured using the rod buckling deformation driving device of the present invention has higher impact resistance and obvious energy absorption effect; on the other hand, because the rod buckling deformation driving device provided by the present invention uses fewer parts and cleverly connects key mechanisms such as the motor, buckling rod, nylon rope, and sensor, the weight of the rod structure is lighter, thereby reducing the mass and energy consumption of the robot and improving the rolling efficiency. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] In order to more clearly illustrate the technical solutions in the present invention or the prior art, the following briefly introduces the drawings required for use in the embodiments or the description of the prior art. Obviously, the drawings described below are some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0021] Figure 1 The overall structure diagram of the rod buckling deformation driving device provided by the present invention;

[0022] Figure 2 The structure of the rod buckling deformation driving device provided by the present invention is schematically shown in FIG. Figure 1 ;

[0023] Figure 3 It is a simplified model diagram of the post-buckling expansion and contraction of the rod and the deflection of the buckled rod of the present invention;

[0024] Figure 4 The structure of the rod buckling deformation driving device provided by the present invention is schematically shown in FIG. Figure 2 ;

[0025] Reference numerals:

[0026] 1-bending rod; 2-position sensor; 21-sensor fixing device; 3-motor; 31-turbine shaft; 4-nylon rope; 5-upper end cover; 6-lower end cover; 7-gear shaft fixing piece; 8-gear shaft; 9-end cover; 91-gasket; 10-bump; 11-connecting plate; 12-steel needle; 51-protrusion; 52-left handle; 53-right handle; 54-end cover plate; 13-bolt; 14-nut. DETAILED DESCRIPTION

[0027] In order to make the purpose, technical solution and advantages of the present invention clearer, the technical solution of the present invention will be clearly and completely described below in conjunction with the drawings of the present invention. Obviously, the described embodiments are part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0028] Figure 1 The overall structure diagram of the rod buckling deformation driving device provided by the present invention; Figure 2 The structure of the rod buckling deformation driving device provided by the present invention is schematically shown in FIG. Figure 1 ,like Figure 1 , Figure 2 As shown, the device includes: a buckling rod 1, a position sensor 2, and a controller; a motor 3 is respectively arranged at both ends of the buckling rod 1, and a nylon rope 4 is arranged between the two motors 3; the position sensor 2 is arranged at the end of the buckling rod 1, and is used to measure the displacement of the buckling rod 1; the controller is used to receive the displacement measured by the position sensor 2 and control the motor 3 according to the displacement, so that the motor 3 drives the nylon rope 4 to contract according to the set amount.

[0029] Specifically, the nylon rope is connected to both ends of the buckling rod. The present invention measures the displacement information of the buckling rod 1 through the sensor 2. After the controller obtains the displacement information, it calculates and obtains the expansion and contraction amount of the nylon rope 4. Thus, the purpose of stretching the nylon rope by the motor and buckling the rod is finally achieved through the expansion and contraction of the nylon rope.

[0030] The amount of contraction of the nylon rope 4 determines the degree of bending of the buckling rod 1. When the device is applied to a tensioning robot, it indirectly determines the change in the position of the robot's center of mass, which is inseparable from the robot's rolling motion. Therefore, in order to accurately and quantitatively control the degree of bending of the buckling rod 1, it is necessary to obtain a quantitative relationship expression between the amount of contraction of the nylon rope 4 and the variable deflection of the buckling rod 1, so as to calculate the driving amount of the motor. To this end, the present invention uses the elliptic integral method in the post-buckling deformation problem of a slender rod to give a corresponding theoretical solution. The basic principle of the elliptic integral method is to perform a series of transformations on the exact differential equation containing the deflection curve, and finally simplify it into the first kind of complete elliptic integral of the rod length and angle, and the second kind of complete elliptic integral of the support spacing and angle. The exact solution of the large deflection buckling load and the maximum deflection of the rod structure can be obtained by looking up the elliptic integral table. Among them, the rod structure can be approximately simplified as Figure 3 Model, Figure 3 This is a simplified model diagram of the post-buckling expansion and contraction of the rod and the deflection of the buckled rod of the present invention, as shown in FIG. Figure 3As shown in the figure, l is the support spacing of the simply supported and constrained compression rod at both ends, F is the axial load on the rod, α is the starting angle, δ is the maximum deflection, l' is the support spacing, Δl is the axial contraction distance of the rod, the origin in the figure is located at one end of the buckling rod and is fixed, named O, the x-axis is the axial direction of the buckling rod, the y-axis represents the deflection of the buckling rod along the axial direction, and the other end of the buckling rod is movable but always located on the x-axis. The support spacing of the simply supported and constrained compression rod at both ends is l, the elastic modulus of the material used for the rod is E, and the bending section coefficient of the rod is I. Under the action of the axial load F, the rod is in a state of post-buckling equilibrium after a large deflection. The starting angle is α, which is expressed as the angle between the tangent direction of the fixed end of the rod and the x-axis, the maximum deflection is δ, which is expressed as the maximum value of the y-axis in the figure, and the support spacing is ;', which represents the spacing between the two end points of the rod after buckling.

[0031] The exact expression for the curvature of the rod is Since the bending moment of a rod is equal to the bending stiffness times the curvature, the exact differential equation for the deflection curve is

[0032]

[0033] Derivative (1) with respect to s, and use This relationship,

[0034]

[0035] make have

[0036]

[0037] Integrating equation (3), we get

[0038]

[0039] Since the bending moment at the end of a simply supported member is zero, we know that the boundary condition is

[0040]

[0041] Substituting into formula (4), we get

[0042] C=cosα (6)

[0043] And θ decreases with s, that is, Therefore

[0044]

[0045] The total length of the component is

[0046]

[0047] remember Introducing variables

[0048]

[0049] Differentiate equation (9) and we get

[0050]

[0051] For θ∈[0,α], we have Right now Substituting equation (10) into equation (8), we get

[0052]

[0053] The integral in the formula is the first kind of complete elliptic integral, denoted by K(p). The value of the integral K is only related to p (the starting angle α), and numerical tables have been given for different p values ​​in the engineering manual. Therefore, based on different p values, the buckling load value under large deflection can be calculated.

[0054] When calculating the deflection of the rod

[0055]

[0056] Therefore, the maximum deflection of the rod is

[0057]

[0058] Substituting equation (10) into the formula and simplifying it, we get

[0059]

[0060] The distance between the two ends of the rod can be calculated in the same way, and the result is

[0061]

[0062] The integral is a complete elliptic integral of the second kind, denoted by E(p).

[0063] Substituting equation (14) into equation (15), we get

[0064]

[0065] The rod buckling deformation driving device provided by the present invention, on the one hand, can quantitatively control the bending degree of the buckled rod through the interaction between the controller and the motor and the sensor, so that the rod buckling deformation driving device provided by the present invention has good flexibility and improves the impact resistance of the rod member. Therefore, the tensioning robot manufactured using the rod buckling deformation driving device of the present invention has higher impact resistance and obvious energy absorption effect; on the other hand, because the rod buckling deformation driving device provided by the present invention uses fewer parts and cleverly connects key mechanisms such as the motor, buckling rod, nylon rope, and sensor, the weight of the rod structure is lighter, thereby reducing the mass and energy consumption of the robot and improving the rolling efficiency.

[0066] Furthermore, in order to make the motor 3 drive the nylon rope 4 to contract according to a set amount, the rod buckling deformation driving device provided by the present invention is as follows: Figure 4 As shown, Figure 4 The structure of the rod buckling deformation driving device provided by the present invention is schematically shown in FIG. Figure 2 The device also includes: an upper end cover 5, a lower end cover 6, and a gear shaft fixing member 7; the motor 3 is fixed between the upper end cover 5 and the lower end cover 6; the gear shaft fixing member 7 is fixed to the lower end cover 6, and a gear shaft 8 that can rotate about its central axis is installed on the gear shaft fixing member 7, and the thread on the gear shaft 8 is meshed with the thread on the turbine shaft 31 of the motor 3; one end of the nylon rope 4 is fixed to the gear shaft 8.

[0067] Specifically, the upper end cover 5 and the lower end cover 6 are fixed into an integral structure by bolts 13 and nuts 14, and the motor 3 is fixed in the cavity formed by the end cover 5 and the lower end cover 6. One end of the nylon rope 4 passes through the upper end cover 5 and is fixed on the gear shaft 8.

[0068] The working principle is as follows: the motor 3 runs, driving the turbine shaft 31 to rotate, the rotation of the turbine shaft 31 drives the gear shaft 8 to rotate, the rotation of the gear shaft 8 causes the nylon rope 4 to begin to expand and contract, and the expansion and contraction of the nylon rope 4 causes the flexion rod 1 to achieve the purpose of flexion.

[0069] The rod bending deformation driving device provided by the present invention fixes the motor in the cavity formed by the upper end cover and the lower end cover, and the nylon rope 4 passes through the upper end cover 5 and is fixed on the gear shaft 8. The device has a simple structure, thereby reducing the weight of the rod structure.

[0070] Furthermore, if Figure 4 As shown, a protrusion 51 with a hollow structure is provided on the upper end cover 5 ; the gear shaft 8 and the turbine shaft 31 are arranged inside the protrusion 51 .

[0071] In order to prevent the nylon rope 4 from being tangled or broken due to external obstacles during the winding process, the rod bending deformation driving device provided by the present invention provides a hollow structure protrusion 51 on the upper end cover 5, and the hollow structure protrusion 51 covers the gear shaft 8 and the turbine shaft 31, so that the gear shaft 8 and the turbine shaft 31 can operate in a relatively safe environment, thereby further improving the quality of the entire device and further improving the efficiency of the robot tumbling.

[0072] Furthermore, if Figure 4 As shown, the cross-section of the gear shaft fixing member 7 is L-shaped, and its horizontal edge is located directly below the opening below the protrusion 51; its vertical edge is fixed to the lower end cover 6; and the gear shaft 8 is installed on the horizontal edge of the gear shaft fixing member 7.

[0073] The rod buckling deformation driving device provided by the present invention, through the gear shaft fixing member 7 with an L-shaped cross-section, allows the gear shaft 8 and the turbine shaft 31 to be completely placed in a relatively safe space, thereby further improving the quality of the entire device and improving the efficiency of the robot's rolling.

[0074] Furthermore, the upper end cover 5 is a Y-shaped structure; the Y-shaped structure includes: a left handle 52, a right handle 53, and an end cover plate 54; the end of the bending rod 1 is movably connected between the left handle 52 and the right handle 53; the motor 3 is installed between the end cover plate 54 and the lower end cover 6.

[0075] Specifically, in order to enable the flexure rod 1 to freely extend and retract, the present invention designs the end of the upper end cover 5 into a Y-shaped structure, and arranges the end of the flexure rod 1 between the left handle 52 and the right handle 53, so that the end of the flexure rod 1 can move freely up and down as it bends, thereby improving the flexibility of the flexure deformation driving device and further improving the impact resistance of the rod component.

[0076] The following provides a specific method for movably connecting the flexion rod 1 with the left handle 52 and the right handle 53, such as Figure 2 As shown, the rod flexure deformation driving device provided by the present invention also includes a circular end cover 9, on the back side of the end cover 9, there are two protrusions 10, the two protrusions 10 are horizontally arranged between the handle 53 and the right handle 54; a connecting plate 11 is fixed to the end of the flexure rod 1, the connecting plate 11 is arranged between the two protrusions 10, and the two protrusions 10, the connecting plate 11, the left handle 52, and the right handle 53 are penetrated together by a steel needle 12 to realize a movable connection.

[0077] Furthermore, a gasket 91 is provided on the front side of the end cover 9 .

[0078] The rod buckling deformation driving device provided by the present invention provides a gasket 91 on the front side of the end cover 9, so that the flexible tensioning robot composed of the deformation driving device has a higher rolling efficiency.

[0079] Furthermore, if Figure 1 As shown, the position sensor 2 includes: a light projector and a light receiver; the light projector is fixed to the side of the protrusion 51, and the light receiver is fixed to the hollow protrusion of the upper end cover 5 corresponding to another motor.

[0080] Specifically, the position sensor 2 is a laser position sensor, which consists of a projector, a light receiver, and a connecting cable. Its ranging principle is: three steps of laser emission, reception and signal processing. The projector is fixed to the side of the upper end cover of the motor at one end of the device for emitting laser signals, and the light receiver is fixed to the side of the upper end cover of the motor at the other end of the device for receiving laser signals. The controller converts the signal into an electrical signal, and amplifies, filters and digitally processes it through a signal processing circuit. Finally, the distance between the projector and the light receiver (i.e., the length of the nylon rope 5) is calculated by parameters such as time, phase or amplitude, and the corresponding voltage is output. After receiving the data from the sensor, the controller converts the voltage analog signal into a digital signal, calculates the bending degree of the flexion rod based on the information collected by the sensor, and feeds back the drive amount of the target of controlling the bending degree to the motor to complete the closed-loop control, thereby achieving the purpose of monitoring the drive amount and accurately controlling it.

[0081] The present invention also provides a flexible tensioning robot, comprising any of the above-described rod buckling deformation driving devices.

[0082] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit it. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or make equivalent replacements for some of the technical features therein. However, these modifications or replacements do not deviate the essence of the corresponding technical solutions from the spirit and scope of the technical solutions of the embodiments of the present invention.

Claims

1. A rod buckling deformation driving device, characterized in that: include: Buckling rod (1), position sensor (2), controller; A motor (3) is provided at each end of the buckling rod (1), and a nylon rope (4) is provided between the two motors (3); The position sensor (2) is arranged at the end of the buckling rod (1) and is used to measure the displacement of the buckling rod (1); The controller is used to receive the displacement measured by the position sensor (2) and control the motor (3) according to the displacement, so that the motor (3) drives the nylon rope (4) to contract according to a set amount; It also includes: an upper end cover (5), a lower end cover (6), and a gear shaft fixing member (7); the motor (3) is fixed between the upper end cover (5) and the lower end cover (6); The gear shaft fixing member (7) is fixed to the lower end cover (6); a gear shaft (8) capable of rotating about its central axis is mounted on the gear shaft fixing member (7); a thread on the gear shaft (8) is meshed with a turbine shaft (31) of the motor (3); and one end of the nylon rope (4) is fixed to the gear shaft (8).

2. The rod buckling deformation driving device according to claim 1, characterized in that: A protrusion (51) with a hollow structure is provided on the upper end cover (5); the gear shaft (8) and the turbine shaft (31) are arranged inside the protrusion (51).

3. The rod buckling deformation driving device according to claim 2, characterized in that: The cross section of the gear shaft fixing member (7) is L-shaped, and its horizontal side is located directly below the opening below the protrusion (51); Its vertical edge is fixed on the lower end cover (6); the gear shaft (8) is mounted on the horizontal edge of the gear shaft fixing member (7).

4. The rod buckling deformation driving device according to claim 1, characterized in that: The upper end cover (5) is a Y-shaped structure; the Y-shaped structure comprises: a left gripping handle (52), a right gripping handle (53), and an end cover plate (54); The end of the buckling rod (1) is movably connected between the left gripping handle (52) and the right gripping handle (53); and the motor (3) is installed between the end cover plate (54) and the lower end cover (6).

5. The rod buckling deformation driving device according to claim 4, characterized in that: It comprises a circular end cover (9), on the back of which two protrusions (10) are arranged. The two protrusions (10) are arranged horizontally between the left gripping handle (52) and the right gripping handle (53); A connecting plate (11) is fixed to the end of the flexure rod (1), the connecting plate (11) is arranged between the two protrusions (10), and the two protrusions (10), the connecting plate (11), the left gripping handle (52), and the right gripping handle (53) are penetrated together by a steel needle (12) to achieve a movable connection.

6. The rod buckling deformation driving device according to claim 5, characterized in that: A gasket (91) is provided on the front side of the end cover (9).

7. The rod buckling deformation driving device according to claim 2, characterized in that: The position sensor (2) comprises: a light projector and a light receiver; the light projector is fixed to the side of the protrusion (51), and the light receiver is fixed to the hollow protrusion of the upper end cover (5) corresponding to another motor.

8. A flexible tensioning robot, characterized in that: It comprises the rod buckling deformation driving device as described in any one of claims 1-7.

Images