A planar omnidirectional three-legged stepping robot driven by piezoelectric wafers

Abstract

The present invention discloses a planar omnidirectional three-legged stepping robot driven by piezoelectric wafers, which relates to the technical field of robots. It includes a base, a driving mechanism A, a driving mechanism B, a driving mechanism C and three actuating mechanisms. The three driving mechanisms are evenly distributed on the outside of the base at 120 degrees. Each actuating mechanism is respectively connected to any one of the driving mechanisms. The driving mechanism A includes a driving hinge, a radial outer foot and a plurality of piezoelectric wafers. The driving hinge includes an assembly end A and a driving end A. The radial outer foot includes an assembly end B and a driving end B. The piezoelectric wafers are used to respectively cause the driving end A and the driving end B to generate periodic deformations under the drive of a control voltage, driving the driving hinge and the radial outer foot to generate deformations, thereby driving the driving mechanism to generate motion. There are three driving mechanisms, and only one driving mechanism is driven each time. Each driving mechanism moves in the same direction and then powers off simultaneously, thereby realizing the planar omnidirectional stepping output of the robot.

Description

Technical Field

[0001] The present invention relates to the technical field of robots, and specifically to a planar omnidirectional three-legged stepping robot driven by piezoelectric wafers. Background Art

[0002] In the field of modern robot research, the development of micro and small robots has attracted much attention, and they show great application potential in many fields such as medical treatment, industrial inspection, and environmental monitoring. The driving method based on the inverse piezoelectric effect of piezoelectric materials has become a research hotspot in the driving technology of micro and small robots due to its significant advantages such as compact structure, rapid response, high precision, and no electromagnetic interference.

[0003] However, most of the existing planar mobile robots have some limitations. Some robots use traditional motors for driving, resulting in a complex overall structure and a large volume, making it difficult to meet the requirements of miniaturization; while some robots based on piezoelectric driving can often only achieve single-direction movement, with poor movement flexibility and unable to operate efficiently in complex planar environments. At the same time, for the existing multi-degree-of-freedom piezoelectric-driven robots, their driving mechanisms and control methods are usually relatively complex, which not only increases the manufacturing cost but also poses high requirements on the accuracy and stability of the control system, restricting their wide application in actual scenarios. Summary of the Invention

[0004] In view of the problems existing in the existing planar mobile robots, such as complex structure, limited degrees of freedom of movement, and difficult control, the present invention proposes a planar omnidirectional three-legged stepping robot driven by piezoelectric wafers, aiming to achieve omnidirectional movement of the robot on a plane, with the advantages of simple structure, flexible movement, and convenient control.

[0005] A planar omnidirectional three-legged stepping robot driven by piezoelectric wafers includes a base, a driving mechanism A, a driving mechanism B, a driving mechanism C, and three actuating mechanisms. The three driving mechanisms are evenly distributed at 120 degrees outside the base, and each actuating mechanism is respectively connected to any one of the driving mechanisms;

[0006] The driving mechanism A includes a driving hinge, a radial outer foot, and a plurality of piezoelectric wafers;

[0007] The driving hinge includes an assembly end A and a driving end A. The head end of the driving end A is fixedly connected to the base, the tail end of the driving end A is fixedly connected to the assembly end A, and piezoelectric wafers are connected to both sides of the driving end A;

[0008] The radial outer foot includes an assembly end B and a driving end B. A bottom threaded hole is provided at the tail end of the driving end B, the head end of the driving end B is connected to the assembly end B, and piezoelectric wafers are connected to both sides of the driving end B;

[0009] The assembly end A is fixedly connected to the assembly end B;

[0010] The actuator is a ball head screw, which is threadedly connected in the bottom threaded hole.

[0011] The piezoelectric wafers are used to make the driving ends A and B generate periodic deformations respectively under the drive of the control voltage, drive the driving hinge and the radial outer foot to generate deformations, thereby driving the driving mechanism to move. There are three driving mechanisms, and only one driving mechanism is driven each time. Each driving mechanism moves in the same direction and then powers off simultaneously, thereby realizing the planar omnidirectional step output of the robot.

[0012] Preferably, the piezoelectric wafers include piezoelectric wafer a, piezoelectric wafer b, piezoelectric wafer c, piezoelectric wafer d, piezoelectric wafer e, piezoelectric wafer f, piezoelectric wafer g, piezoelectric wafer h, piezoelectric wafer i, piezoelectric wafer j, piezoelectric wafer k, piezoelectric wafer l.

[0013] Piezoelectric wafer c and piezoelectric wafer d are symmetrically installed on both sides of the driving hinge of driving mechanism A.

[0014] Piezoelectric wafer e and piezoelectric wafer f are symmetrically installed on both sides of the driving hinge of driving mechanism B.

[0015] Piezoelectric wafer a and piezoelectric wafer b are symmetrically installed on both sides of the driving hinge of driving mechanism C.

[0016] Piezoelectric wafer k and piezoelectric wafer l are symmetrically installed on both sides of the radial outer foot of driving mechanism A.

[0017] Piezoelectric wafer h and piezoelectric wafer i are symmetrically installed on both sides of the radial outer foot of driving mechanism B.

[0018] Piezoelectric wafer g and piezoelectric wafer j are symmetrically installed on both sides of the radial outer foot of driving mechanism C.

[0019] Preferably, the material of the driving mechanism is 65Mn spring steel after heat treatment.

[0020] Preferably, the base and the driving hinge are integrally formed.

[0021] Preferably, a central hole is provided at the center of the base, and three through holes are provided on the base on the outer circumference of the axis of the central hole and are distributed at 120 degrees.

[0022] Compared with the prior art, the beneficial effects of the present invention are as follows: The invention adopts a driving method based on piezoelectric wafers and a simple three-foot structure, abandons the traditional complex transmission mechanism, makes the overall structure of the robot more compact, and reduces the manufacturing and maintenance costs.

[0023] Through the collaborative work of three drive mechanisms distributed at 120°, the present invention can achieve the omnidirectional movement of the robot on a plane, including forward, backward, left turn, right turn, and linear movement in any direction, greatly improving the movement flexibility and adaptability of the robot in a complex planar environment;

[0024] By utilizing the high-precision drive characteristics of piezoelectric wafers and combining precise actuators, the present invention can achieve precise control of the robot's movement, meeting the application requirements in high-precision operation scenarios, such as micro-assembly, micro-operation, and other fields;

[0025] The fast response characteristics of the piezoelectric wafers of the present invention enable the robot to quickly respond to control instructions, having obvious advantages in scenarios requiring fast actions, such as emergency detection, rapid positioning, and other tasks. BRIEF DESCRIPTION OF THE DRAWINGS

[0026] In order to more clearly illustrate the technical solutions in the embodiments of the present invention, the following will briefly introduce the drawings required for use in the embodiments or the description of the prior art. Obviously, the drawings in the following description are only some embodiments of the present invention. For those of ordinary skill in the art, without creative efforts, other drawings can also be obtained based on these drawings.

[0027] Figure 1 is a schematic three-dimensional structure diagram of the present invention;

[0028] Figure 2 is a top view of the present invention;

[0029] Figure 3 is a left view of the present invention;

[0030] Figure 4 is a schematic overall structure diagram of the base and drive hinge of the present invention;

[0031] Figure 5 is a schematic radial outer foot structure diagram of the present invention;

[0032] Figure 6 is a waveform diagram of the linear displacement drive signal in the X-axis direction of the present invention;

[0033] Figure 7 is a waveform diagram of the linear displacement drive signal in the Y-axis direction of the present invention;

[0034] Figure 8 is a waveform diagram of the angular displacement drive signal for rotation about the Z-axis of the present invention;

[0035] Figure 9 is a schematic drive principle diagram of drive mechanism A of the present invention;

[0036] Figure 10This is the driving principle diagram when the linear displacement of the present invention is output in the X-axis direction.

[0037] Figure 11 This is the driving principle diagram when the linear displacement of the present invention is output in the Y-axis direction.

[0038] Figure 12 This is the driving principle diagram when the rotational angular displacement of the present invention is output around the Z-axis direction.

[0039] Among them, the reference numerals of each component in the figure are as follows:

[0040] 1: Assembly screw A; 2: Ball head screw; 3: Radial outer foot; 4: Assembly screw B; 5: Driving mechanism A; 6: Driving mechanism B; 7: Driving mechanism C; 8: Piezoelectric wafer; 9: Driving hinge; 10: Base; 11: Assembly threaded hole A; 12: Driving end A; 13: Assembly threaded hole B; 14: Assembly end A; 15: Central hole; 16: Bottom threaded hole; 17: Driving end B; 18: Assembly threaded hole C; 19: Assembly end B; 20: Assembly threaded hole D;

[0041] 1-1: Piezoelectric wafer a; 1-2: Piezoelectric wafer b; 1-3: Piezoelectric wafer c; 1-4: Piezoelectric wafer d; 1-5: Piezoelectric wafer e; 1-6: Piezoelectric wafer f;

[0042] 2-1: Piezoelectric wafer g; 2-2: Piezoelectric wafer h; 2-3: Piezoelectric wafer i; 2-4: Piezoelectric wafer j; 2-5: Piezoelectric wafer k; 2-6: Piezoelectric wafer l; Specific implementation mode

[0043] Embodiment 1 of the present invention:

[0044] Please refer to Figures 1-5 As shown, a planar omnidirectional three-legged stepping robot based on piezoelectric wafer drive includes a base 10, a driving mechanism A 5, a driving mechanism B 6, a driving mechanism C 7, and three execution mechanisms. The three driving mechanisms are evenly distributed at 120 degrees outside the base 10, and each execution mechanism is respectively connected to any one of the driving mechanisms;

[0045] A central hole 15 is provided at the center of the base 10, and three through holes distributed at 120 degrees are provided on the base 10 outside the axis of the central hole 15. The central hole 15 and the through holes are used to connect other external loads;

[0046] The driving mechanism A 5 includes a driving hinge 9, a radial outer foot 3, and a plurality of piezoelectric wafers 8;

[0047] The driving hinge 9 includes an assembly end A14 and a driving end A12. The head end of the driving end A12 is fixedly connected to the base 10, the tail end of the driving end A12 is fixedly connected to the assembly end A14. The assembly end A14 is provided with an assembly threaded hole A11 and an assembly threaded hole B13. On both sides of the driving end A12, a piezoelectric wafer 8 is adhered by epoxy resin;

[0048] The radial outer foot 3 includes an assembly end B19 and a driving end B17. The tail end of the driving end B17 is provided with a bottom threaded hole 16. The head end of the driving end B17 is connected to the assembly end B19. The assembly end B19 is provided with an assembly threaded hole C18 and an assembly threaded hole D20. On both sides of the driving end B17, a piezoelectric wafer 8 is adhered by epoxy resin;

[0049] The assembly screw A1 passes through the assembly threaded hole C18 and the assembly threaded hole A11, and the assembly screw B4 passes through the assembly threaded hole D20 and the assembly threaded hole B13 to realize the connection between the assembly end A14 and the assembly end B19;

[0050] The actuator is a ball head screw 2, and the ball head screw 2 is threadedly connected in the bottom threaded hole 16;

[0051] The piezoelectric wafers 8 are used to respectively cause the driving end A12 and the driving end B17 to generate periodic deformations under the drive of a control voltage, drive the driving hinge 9 and the radial outer foot 3 to generate deformations, thereby driving the driving mechanism to generate motion. There are three driving mechanisms, and only one driving mechanism is driven each time. Each driving mechanism moves in the same direction and then powers off simultaneously, thereby realizing the planar omnidirectional stepping output of the robot.

[0052] Furthermore, the piezoelectric wafers 8 include piezoelectric wafer a1-1, piezoelectric wafer b1-2, piezoelectric wafer c1-3, piezoelectric wafer d1-4, piezoelectric wafer e1-5, piezoelectric wafer f1-6, piezoelectric wafer g2-1, piezoelectric wafer h2-2, piezoelectric wafer i2-3, piezoelectric wafer j2-4, piezoelectric wafer k2-5, piezoelectric wafer l2-6;

[0053] The piezoelectric wafers c1-3 and d1-4 are symmetrically installed on both sides of the driving hinge 9 of the driving mechanism A5;

[0054] The piezoelectric wafers e1-5 and f1-6 are symmetrically installed on both sides of the driving hinge 9 of the driving mechanism B6;

[0055] The piezoelectric wafers a1-1 and b1-2 are symmetrically installed on both sides of the driving hinge 9 of the driving mechanism C7;

[0056] The piezoelectric wafers k2-5 and l2-6 are symmetrically installed on both sides of the radial outer foot 3 of the driving mechanism A5;

[0057] The piezoelectric wafers h2-2 and i2-3 are symmetrically installed on both sides of the radial outer feet of the driving mechanism B6;

[0058] The piezoelectric wafers g2-1 and j2-4 are symmetrically installed on both sides of the radial outer feet of the driving mechanism C7.

[0059] Furthermore, the material of the driving mechanism is 65Mn spring steel after heat treatment;

[0060] Furthermore, the base 10 and the driving hinge 9 are integrally formed.

[0061] The working principle of the present invention:

[0062] Referring to Figures 1 to 5 、 Figure 9 In the first embodiment, taking a single driving mechanism A5 as an example; as shown in a of Figure 9 , the left side of the driving mechanism A5 is fixed on the base 10, and only the right driving hinge 9 and the radial outer foot 3 can move. The radial outer foot 3 is fixed to the driving hinge 9 by the assembly screw A1 and the assembly screw B4. A voltage is applied to the piezoelectric wafers k2-5 and l2-6 on both sides of the radial outer foot 3. The piezoelectric wafer l2-6 is applied with a voltage -U1 (not shown in the figure, -U1 only represents the voltage value), and the piezoelectric wafer k2-5 is applied with a voltage U1 (not shown in the figure, U1 only represents the voltage value). Under the inverse piezoelectric effect, the piezoelectric wafers l2-6 and k2-5 bend in the positive X-axis direction, thereby driving the radial outer foot 3 to bend in the positive X-axis direction, and then driving the ball head screw 2 at the bottom of the driving mechanism A5 to move in the positive X-axis direction;

[0063] As shown in b of Figure 9 , a voltage is applied to the piezoelectric wafers d1-4 and c1-3 on both sides of the driving hinge 9. The piezoelectric wafer d1-4 is applied with a voltage -U1, and the piezoelectric wafer c1-3 is applied with a voltage U1. Under the action of the inverse piezoelectric effect, the piezoelectric wafers d1-4 and c1-3 bend in the positive Y-axis direction, thereby driving the driving hinge 9 to bend in the positive Y-axis direction, and then driving the ball head screw 2 at the bottom of the driving mechanism A5 to move in the positive Y-axis direction;

[0064] When the piezoelectric wafers 8 on both sides of the radial outer foot 3 and the driving hinge 9 are simultaneously energized, and voltages U1~-U1 are respectively applied to the piezoelectric wafers k2-5 and l2-6, and the piezoelectric wafers c1-3 and d1-4. Under the action of the inverse piezoelectric effect, the driving hinge 9 is driven to bend in the positive Y-axis direction, and the radial outer foot 3 is driven to bend in the positive X-axis direction, thereby driving the ball head screw 2 at the bottom of the driving mechanism A5 to move in the direction of 45° between the X-axis and the Y-axis;

[0065] By adjusting the positive / negative and magnitude of the voltage applied to the piezoelectric wafer 8, the ball head screw 2 at the bottom of the driving mechanism A5 can be made to move in a circular trajectory;

[0066] As Figure 9 shown in c, when voltages U2 to -U2 (not shown in the figure, where U2 and -U2 only represent voltage values) are applied to the piezoelectric wafers c1-3, piezoelectric wafers k2-5, piezoelectric wafers d1-4, and piezoelectric wafers l2-6 respectively, under the action of the inverse piezoelectric effect, the driving hinge 9 is driven to bend in the positive Y-axis direction, and the radial outer foot 3 is driven to bend in the positive X-axis direction, thereby driving the ball head screw 2 at the bottom of the driving mechanism A5 to move at a 45° angle between the X-axis and the Y-axis and finally land on the circular trajectory.

[0067] As Figures 1-12 shown, the specific working process of the present invention is as follows:

[0068] 1. As Figures 1 to 5 , Figure 6 and Figure 10 shown, taking the bending deformation of the radial outer foot 3 of the driving mechanism A5 in the X-axis direction as the positive direction, and the bending deformation of the driving mechanisms B6 and C7 driving the ball head screw 2 in the X-axis direction as the positive direction, the robot can generate a linear displacement output along the positive X-axis direction;

[0069] At t = 0, the piezoelectric wafer 8 is in an unpowered state. At this time, all the radial outer feet 3 and all the driving hinges 9 are in their original lengths, and the robot has no displacement output;

[0070] In the stage from 0 to T / 4, voltage signals as Figure 6 shown in a are simultaneously applied to the piezoelectric wafers 8 on both sides of the radial outer foot 3 of the driving mechanism A5. During the process where the voltage of the piezoelectric wafer k2-5 slowly increases to U and the voltage of the piezoelectric wafer l2-6 slowly decreases to -U, under the inverse piezoelectric effect, the piezoelectric wafers l2-6 and k2-5 bend towards the outside of the robot, driving the radial outer foot 3 of the driving mechanism A5 to bend in the positive X-axis direction, thereby driving the ball head screw 2 at the bottom of the driving mechanism A5 to move a distance L in the positive X-axis direction, and the driving mechanism A5 moves a distance L in the positive X-axis direction. In the stage from 0 to T / 4, when the driving mechanism A5 drives the ball head screw 2 to move in the positive X-axis direction, the ground provides a frictional force in the positive X-axis direction to the driving mechanism A5, causing the robot to have a tendency to move in the positive X-axis direction. The driving mechanisms B6 and C7 remain stationary, so the ground provides a frictional force in the negative X-axis direction to the driving mechanisms B6 and C7. The frictional force provided by the ground to the driving mechanisms B6 and C7 in the negative X-axis direction is greater than the frictional force provided by the ground to the driving mechanism A5 in the positive X-axis direction, and the position of the base 10 remains unchanged, and the robot has no displacement output;

[0071] During the T / 4 - T / 2 stage, voltage signals are simultaneously applied to the piezoelectric wafers 8 on both sides of the driving hinge 9 of the driving mechanism C7 Figure 6 as shown in b. When the voltage of the piezoelectric wafer b1 - 2 slowly increases to U3 and the voltage of the piezoelectric wafer a1 - 1 slowly decreases to -U3, voltage signals are simultaneously applied to the piezoelectric wafers 8 on both sides of the radial outer foot 3 of the driving mechanism C7 Figure 6 as shown in c. During the process when the voltage of the piezoelectric wafer j2 - 4 slowly increases to U4 and the voltage of the piezoelectric wafer g2 - 1 slowly decreases to -U4, under the inverse piezoelectric effect, the piezoelectric wafers a1 - 1 and b1 - 2 bend counterclockwise around the Z - axis, and the piezoelectric wafers g2 - 1 and j2 - 4 bend towards the inside of the robot, driving the driving hinge 9 of the driving mechanism C7 and the radial outer foot 3 of the driving mechanism C7 to bend. The two bends are combined, thereby driving the bottom ball - head screw 2 of the driving mechanism C7 to move a distance L in the positive X - axis direction. During the T / 4 - T / 2 stage, when the driving mechanism C7 drives its bottom ball - head screw 2 to move in the positive X - axis direction, the ground provides a frictional force in the positive X - axis direction to the driving mechanism C7, causing the robot to have a tendency to move in the positive X - axis direction. The driving mechanisms A5 and B6 remain stationary, so the ground provides a frictional force in the negative X - axis direction to the driving mechanisms A5 and B6. The frictional force provided by the ground to the driving mechanisms A5 and B6 in the negative X - axis direction is greater than the frictional force provided by the ground to the driving mechanism C7 in the positive X - axis direction. The position of the base 10 remains unchanged, and the robot has no displacement output;

[0072] During the T / 2 - 3T / 4 stage, voltage signals are simultaneously applied to the piezoelectric wafers 8 on both sides of the driving hinge 9 of the driving mechanism B6 Figure 6 as shown in d. When the voltage of the piezoelectric wafer e1 - 5 slowly increases to U5 and the voltage of the piezoelectric wafer f1 - 6 slowly decreases to -U5, and voltage signals are simultaneously applied to the piezoelectric wafers 8 on both sides of the radial outer foot 3 of the driving mechanism B6 Figure 6When the voltage signal shown in Fig. e is applied, during the process that the voltage of piezoelectric wafer i2-3 slowly increases to U6 and the voltage of piezoelectric wafer h2-2 slowly decreases to -U6, under the inverse piezoelectric effect, piezoelectric wafers f1-6 and e1-5 bend clockwise around the Z axis, and piezoelectric wafers h2-2 and i2-3 bend towards the inside of the robot, driving the driving hinge 9 of driving mechanism B6 and the radial outer foot 3 of driving mechanism B6 to bend. The two bends are combined, thereby driving the bottom ball screw 2 of driving mechanism B6 to move a distance of L in the positive X-axis direction. During the T / 2~3T / 4 stage, when driving mechanism B6 drives its bottom ball screw 2 to move in the positive X-axis direction, the ground gives driving mechanism B6 a frictional force in the positive X-axis direction, making the robot tend to move in the positive X-axis direction. Driving mechanisms A5 and C7 remain stationary, so the ground provides driving mechanisms A5 and C7 with a frictional force in the negative X-axis direction. The frictional force provided by the ground to driving mechanisms A5 and C7 in the negative X-axis direction is greater than the frictional force provided by the ground to driving mechanism B6 in the positive X-axis direction, and the position of the base 10 remains unchanged, and the robot has no displacement output;

[0073] Within the 3T / 4~T stage, the voltage of piezoelectric wafer 8 slowly decreases to 0. Under the inverse piezoelectric effect, the length of piezoelectric wafer 8 returns to its original length. The radial outer feet 3 of driving mechanism A5, the driving hinges 9 of driving mechanism C7, the driving hinges 9 of driving mechanism B6, the radial outer feet 3 of driving mechanism B6, and the radial outer feet 3 of driving mechanism C7 all tend to return to their original positions, all providing a force in the negative X-axis direction to the three driving mechanisms. The ground provides the three driving mechanisms with a frictional force in the positive X-axis direction. The force provided to the three driving mechanisms in the negative X-axis direction is less than the frictional force provided by the ground to the three driving mechanisms in the positive X-axis direction, thereby driving the base 10 to move a distance of L in the positive X-axis direction, and the robot has a displacement output of L;

[0074] If this process is repeated continuously, the robot can achieve a large-stroke step-by-step linear displacement output in the positive X-axis direction. By applying reverse driving signals to each piezoelectric wafer 8, the robot can achieve a large-stroke step-by-step linear displacement output in the negative X-axis direction.

[0075] 2. As Figures 1 to 5 、 Figure 7 and Figure 11 shown, taking the bending deformation of the driving hinge 9 of driving mechanism A5 in the positive Y-axis direction as the positive direction, and the bending deformation of driving mechanisms B6 and C7 driving the bottom ball screw 2 in the positive Y-axis direction as the positive direction, this robot can generate a linear displacement output in the positive Y-axis direction;

[0076] At time 0, all piezoelectric wafers 8 are in an unpowered state. At this time, all radial outer feet 3 and all drive hinges 9 are in their original length states, and the robot has no displacement output;

[0077] During the period from 0 to T / 4, while applying the Figure 7 voltage signal shown in a of to the piezoelectric wafers 8 on both sides of the drive hinge 9 of the drive mechanism A5, during the process that the voltage of the piezoelectric wafers c1-3 slowly increases to U and the voltage of the piezoelectric wafers d1-4 slowly decreases to -U, under the inverse piezoelectric effect, the piezoelectric wafers d1-4 and the piezoelectric wafers c1-3 bend and deform in the positive Y-axis direction, driving the drive hinge 9 of the drive mechanism A5 to bend in the positive Y-axis direction, thereby driving the bottom ball screw 2 of the drive mechanism A5 to move a distance of L in the positive Y-axis direction. During the period from 0 to T / 4, when the drive mechanism A5 drives its bottom ball screw 2 to move in the positive Y-axis direction, the ground gives the drive mechanism A5 a frictional force in the positive Y-axis direction, making the robot have a tendency to move in the positive Y-axis direction. The drive mechanism B6 and the drive mechanism C7 remain stationary, so the ground provides the drive mechanism B6 and the drive mechanism C7 with a frictional force in the negative Y-axis direction. The frictional force provided by the ground to the drive mechanism B6 and the drive mechanism C7 in the negative Y-axis direction is greater than the frictional force provided by the ground to the drive mechanism A5 in the positive Y-axis direction. The position of the base 10 remains unchanged, and the robot has no displacement output;

[0078] During the period from T / 4 to T / 2, while applying the Figure 7 voltage signal shown in b of to the piezoelectric wafers 8 on both sides of the drive hinge 9 of the drive mechanism C7, the voltage of the piezoelectric wafers a1-1 slowly increases to U7 and the voltage of the piezoelectric wafers b1-2 slowly decreases to -U7, and while applying the Figure 7When the voltage signal shown in c, during the process that the voltage of piezoelectric wafer j2-4 slowly increases to U8 and the voltage of piezoelectric wafer g2-1 slowly decreases to -U8, under the inverse piezoelectric effect, piezoelectric wafers a1-1 and b1-2 bend clockwise around the Z axis, and piezoelectric wafers g2-1 and j2-4 bend towards the inside of the robot, driving the driving hinge 9 of driving mechanism C7 and the radial outer foot 3 of driving mechanism C7 to bend. The two bends are combined, thus driving the bottom ball screw 2 of driving mechanism C7 to move a distance of L in the positive Y-axis direction. During the T / 4~T / 2 stage, when driving mechanism C7 drives its bottom ball screw 2 to move in the positive Y-axis direction, the ground provides a frictional force in the positive Y-axis direction to driving mechanism C7, making the robot tend to move in the positive Y-axis direction. Driving mechanisms A5 and B6 remain stationary, so the ground provides a frictional force in the negative Y-axis direction to driving mechanisms A5 and B6. The frictional force provided by the ground to driving mechanisms A5 and B6 in the negative Y-axis direction is greater than the frictional force provided by the ground to driving mechanism C7 in the positive Y-axis direction. The position of the base 10 remains unchanged, and the robot has no displacement output;

[0079] During the T / 2~3T / 4 stage, while simultaneously applying Figure 7 the voltage signal shown in d to the piezoelectric wafers 8 on both sides of the driving hinge 9 of driving mechanism B6, the voltage of piezoelectric wafer e1-5 slowly increases to U9 and the voltage of piezoelectric wafer f1-6 slowly decreases to -U9, and while simultaneously applying Figure 7 the voltage signal shown in e to the piezoelectric wafers 8 on both sides of the radial outer foot 3 of driving mechanism B6, during the process that the voltage of piezoelectric wafer h2-2 slowly increases to U10 and the voltage of piezoelectric wafer i2-3 slowly decreases to -U10, under the inverse piezoelectric effect, piezoelectric wafers f1-6 and e1-5 bend clockwise around the Z axis, and piezoelectric wafers h2-2 and i2-3 bend towards the outside of the robot, driving the driving hinge 9 of driving mechanism B6 and the radial outer foot 3 of driving mechanism B6 to bend. The two bends are combined, thus driving its bottom ball screw 2 to move a distance of L in the positive Y-axis direction. During the T / 2~3T / 4 stage, when driving mechanism B6 drives its bottom ball screw 2 to move in the positive Y-axis direction, the ground provides a frictional force in the positive Y-axis direction to driving mechanism B6, making the robot tend to move in the positive Y-axis direction. Driving mechanisms A5 and C7 remain stationary, so the ground provides a frictional force in the negative Y-axis direction to driving mechanisms A5 and C7. The frictional force provided by the ground to driving mechanisms A5 and C7 in the negative Y-axis direction is greater than the frictional force provided by the ground to driving mechanism B6 in the positive X-axis direction. The position of the base 10 remains unchanged, and the robot has no displacement output;

[0080] In the period from 3T / 4 to T, the voltage of the piezoelectric wafer 8 slowly decreases to 0. Under the inverse piezoelectric effect, the piezoelectric wafer 8 returns to its original length. The radial outer feet 3 of the driving mechanism B6, the radial outer feet 3 of the driving mechanism C7, the driving hinges 9 of the driving mechanism A5, the driving hinges 9 of the driving mechanism B6, and the driving hinges 9 of the driving mechanism C7 all tend to return to their original positions, all applying a force to the three driving mechanisms to move in the negative Y-axis direction. The ground applies a frictional force to the three driving mechanisms in the positive Y-axis direction. The force applied to the three driving mechanisms to move in the negative Y-axis direction is less than the frictional force applied by the ground to the three driving mechanisms in the positive Y-axis direction, thereby driving the base 10 to move a distance of L in the positive Y-axis direction, and the displacement output of the robot is L.

[0081] If this process is continuously repeated, the robot can achieve a large-stroke step linear displacement output in the positive Y-axis direction. By applying a reverse driving signal to each piezoelectric wafer 8, the robot can achieve a large-stroke step linear displacement output in the negative Y-axis direction.

[0082] 3. As Figures 1 to 5 、 Figure 8 and Figure 12 shown, taking the bending deformation of the driving hinge 9 of the driving mechanism A5 in the positive Y-axis direction as the positive direction, and the bending deformation of the driving mechanisms B6 and C7 driving their bottom ball head screws 2 in the positive Y-axis direction as the positive direction, the robot can generate a rotational angular displacement output in the clockwise direction around the Z-axis during this process;

[0083] At t = 0, all the piezoelectric wafers 8 are in the non-energized state. At this time, all the radial outer feet 3 and all the driving hinges 9 are in the original length state, and the robot has no rotational angular displacement output;

[0084] In the period from 0 to T / 4, the piezoelectric wafers 8 on both sides of the driving hinge 9 of the driving mechanism A5 are simultaneously applied with Figure 9When the voltage signal shown is applied, during the process that the voltage of piezoelectric wafers c1 - 3 slowly increases to U and the voltage of piezoelectric wafers d1 - 4 slowly decreases to -U, under the inverse piezoelectric effect, piezoelectric wafers d1 - 4 and piezoelectric wafers c1 - 3 bend and deform counterclockwise along the Z - axis, driving the driving hinge 9 of the driving mechanism A5 to rotate counterclockwise by θ along the Z - axis. Thereby driving the ball - head screw 2 at its bottom to rotate counterclockwise by θ along the Z - axis. In the stage of 0~T / 4, the driving mechanism A5 drives the ball - head screw 2 at its bottom to rotate counterclockwise by θ along the Z - axis. The frictional torque provided by the ground for the driving mechanism A5 to rotate counterclockwise around the Z - axis makes the robot tend to rotate counterclockwise around the Z - axis. The driving mechanism B6 and the driving mechanism C7 remain stationary. Thus, the ground provides a frictional torque for the driving mechanism B6 and the driving mechanism C7 to rotate clockwise around the Z - axis. The frictional torque provided by the ground for the driving mechanism B6 and the driving mechanism C7 to rotate clockwise around the Z - axis is greater than the frictional torque provided by the ground for the driving mechanism A5 to rotate counterclockwise around the Z - axis. With the position of the base 10 unchanged, the robot has no angular displacement output;

[0085] In the stage of T / 4~T / 2, while applying the voltage signal shown to the piezoelectric wafers 8 on both sides of the driving hinge 9 of the driving mechanism B6 Figure 9 When the voltage signal shown is applied, during the process that the voltage of piezoelectric wafers f1 - 6 slowly increases to U and the voltage of piezoelectric wafers e1 - 5 slowly decreases to -U, under the inverse piezoelectric effect, piezoelectric wafers f1 - 6 and piezoelectric wafers e1 - 5 bend and deform counterclockwise along the Z - axis, driving the driving hinge 9 of the driving mechanism B6 to rotate counterclockwise by θ along the Z - axis. Thereby driving the ball - head screw 2 at its bottom to rotate counterclockwise by θ along the Z - axis. In the stage of T / 4~T / 2, the driving mechanism B6 drives the ball - head screw 2 at its bottom to rotate counterclockwise by θ along the Z - axis. The frictional torque provided by the ground for the driving mechanism B6 to rotate counterclockwise around the Z - axis makes the robot tend to rotate counterclockwise around the Z - axis. The driving mechanism A5 and the driving mechanism C7 remain stationary. Thus, the ground provides a frictional torque for the driving mechanism A5 and the driving mechanism C7 to rotate clockwise around the Z - axis. The frictional torque provided by the ground for the driving mechanism A5 and the driving mechanism C7 to rotate clockwise around the Z - axis is greater than the frictional torque provided by the ground for the driving mechanism B6 to rotate counterclockwise around the Z - axis. With the position of the base 10 unchanged, the robot has no angular displacement output;

[0086] In the stage of T / 2~3T / 4, while applying the voltage signal shown to the piezoelectric wafers 8 on both sides of the driving hinge 9 of the driving mechanism C7 Figure 9When the voltage signal shown is applied, during the process in which the voltage of piezoelectric wafer b1-2 slowly increases to U and the voltage of piezoelectric wafer a1-1 slowly decreases to -U, under the inverse piezoelectric effect, piezoelectric wafer a1-1 and piezoelectric wafer b1-2 bend and deform counterclockwise along the Z-axis, driving the driving hinge 9 of driving mechanism C7 to rotate counterclockwise by θ along the Z-axis. As a result, the ball head screw 2 at its bottom rotates counterclockwise by θ along the Z-axis. During the T / 2 - 3T / 4 stage, driving mechanism C7 drives the ball head screw 2 at its bottom to rotate counterclockwise by θ along the Z-axis. The frictional torque provided by the ground for driving mechanism C7 to rotate counterclockwise around the Z-axis causes the robot to have a tendency to rotate counterclockwise around the Z-axis. Driving mechanisms A5 and B6 remain stationary. Thus, the ground provides a frictional torque for driving mechanisms A5 and B6 to rotate clockwise around the Z-axis. The frictional torque provided by the ground for driving mechanisms A5 and B6 to rotate clockwise around the Z-axis is greater than the frictional torque provided by the ground for driving mechanism C7 to rotate counterclockwise around the Z-axis. With the position of the base 10 unchanged, the robot has no angular displacement output.

[0087] During the 3T / 4 - T stage, the voltage of piezoelectric wafer 8 slowly decreases to 0. Under the inverse piezoelectric effect, piezoelectric wafer 8 returns to its original length. The driving hinges 9 of driving mechanism A5, driving mechanism B6, and driving mechanism C7 all tend to return to their original positions, providing a torque for each of the three driving mechanisms to rotate clockwise around the Z-axis. The ground provides a frictional torque for driving mechanisms A5, B6, and C7 to rotate counterclockwise around the Z-axis. The torque for driving mechanisms A5, B6, and C7 to rotate clockwise around the Z-axis is less than the frictional torque provided by the ground for driving mechanisms A5, B6, and C7 to rotate counterclockwise around the Z-axis. As a result, the base 10 is driven to rotate by θ along the Z-axis, and the robot has an angular displacement output of θ.

[0088] If this process is repeated continuously, the robot can achieve a large-stroke stepwise rotational angular displacement output in the clockwise direction around the Z-axis. By applying reverse driving signals to each piezoelectric wafer 8, the robot can achieve a large-stroke stepwise rotational angular displacement output in the counterclockwise direction around the Z-axis.

[0089] Driven by the three driving mechanisms, the robot can produce a linear displacement output in the X-axis direction or Y-axis direction and a rotational angular displacement output around the Z-axis direction. By repeating this process cyclically, the robot can achieve a planar three-degree-of-freedom motion output.

Claims

1. A planar omnidirectional three-legged stepping robot driven by piezoelectric wafers, characterized in that: It includes a base (10), a driving mechanism A (5), a driving mechanism B (6), a driving mechanism C (7) and three actuating mechanisms. The three driving mechanisms are evenly distributed at 120 degrees outside the base (10), and each actuating mechanism is respectively connected to any one of the driving mechanisms; The driving mechanism A (5) includes a driving hinge (9), a radial outer foot (3) and a plurality of piezoelectric wafers (8); The driving hinge (9) includes an assembly end A (14) and a driving end A (12). The head end of the driving end A (12) is fixedly connected to the base (10), the tail end of the driving end A (12) is fixedly connected to the assembly end A (14), and piezoelectric wafers (8) are connected to both sides of the driving end A (12) parallel to the axial direction of the base (10); The radial outer foot (3) includes an assembly end B (19) and a driving end B (17). A bottom threaded hole (16) is provided at the tail end of the driving end B (17). The head end of the driving end B (17) is connected to the assembly end B (19), and piezoelectric wafers (8) are connected to both sides of the driving end B (17) close to and away from the base (10); The assembly end A (14) is fixedly connected to the assembly end B (19); The actuating mechanism is a ball screw (2), and the ball screw (2) is threadedly connected in the bottom threaded hole (16); The piezoelectric wafers (8) are used to respectively cause the driving end A (12) and the driving end B (17) to generate periodic deformations under the drive of a control voltage, driving the driving hinge (9) and the radial outer foot (3) to generate deformations, thereby driving the driving mechanism to move. There are three driving mechanisms, and only one driving mechanism is driven each time. Each driving mechanism moves in the same direction and then powers off simultaneously, thereby realizing the planar omnidirectional stepping output of the robot.

2. The omnidirectional planar three-legged stepping robot based on piezoelectric wafer driving according to claim 1, characterized in that: The piezoelectric wafers (8) include piezoelectric wafer a (1-1), piezoelectric wafer b (1-2), piezoelectric wafer c (1-3), piezoelectric wafer d (1-4), piezoelectric wafer e (1-5), piezoelectric wafer f (1-6), piezoelectric wafer g (2-1), piezoelectric wafer h (2-2), piezoelectric wafer i (2-3), piezoelectric wafer j (2-4), piezoelectric wafer k (2-5), piezoelectric wafer l (2-6); The piezoelectric wafer c (1-3) and the piezoelectric wafer d (1-4) are symmetrically installed on both sides of the driving hinge (9) of the driving mechanism A (5); The piezoelectric wafer e (1-5) and the piezoelectric wafer f (1-6) are symmetrically installed on both sides of the driving hinge (9) of the driving mechanism B (6); The piezoelectric wafer a (1-1) and the piezoelectric wafer b (1-2) are symmetrically installed on both sides of the driving hinge (9) of the driving mechanism C (7); The piezoelectric wafer k (2-5) and the piezoelectric wafer l (2-6) are symmetrically installed on both sides of the radial outer foot (3) of the driving mechanism A (5); The piezoelectric wafer h (2-2) and the piezoelectric wafer i (2-3) are symmetrically installed on both sides of the radial outer foot of the driving mechanism B (6); The piezoelectric wafer g (2-1) and the piezoelectric wafer j (2-4) are symmetrically installed on both sides of the radial outer foot of the driving mechanism C (7).

3. The omnidirectional planar three-legged stepping robot driven by piezoelectric wafers according to claim 1, wherein: The material of the driving mechanism is 65Mn spring steel after heat treatment.

4. A planar omnidirectional three-legged stepping robot based on piezoelectric wafer drive according to claim 1, characterized in that: The base (10) and the driving hinge (9) are integrally formed and designed.

5. The omnidirectional planar three-legged stepping robot driven by a piezoelectric wafer according to claim 1, wherein: The base (10) is provided with a central hole (15) at its center, and three through holes are provided on the base (10) at the outer periphery of the axis of the central hole (15) and are distributed at 120 degrees.

Images