An active deployable spherical robot based on ratchet and pawl

Abstract

The present invention discloses an active deployment spherical robot based on ratchets and pawls, belonging to the field of spherical robots; it includes a frame, two hemispherical ball wheel mechanisms, and a deployment drive mechanism; the deployment drive mechanism includes a main shaft, a lateral deployment drive mechanism, and a rotation drive mechanism; each ball wheel mechanism includes an inner end ball wheel assembly, a three-blade impeller deformation mechanism, and an outer end ball wheel assembly. The lateral deployment drive mechanism drives the main shaft to move outward, causing the three-blade impeller deformation mechanism to deploy radially, and then the rotation drive mechanism drives the three-blade impeller deformation mechanism to rotate circumferentially through the inner end ball wheel assembly, enabling the entire robot to move forward. By setting the three-blade impeller deformation mechanism and the lateral deployment drive mechanism, the deployment and deformation of the hemispherical wheels of the spherical robot can be achieved, and the obstacle-crossing ability of the spherical robot can be improved by expanding the radius of the ball wheels; this solution has the advantages of few driving components, low energy consumption, small volume, simple structure, and strong obstacle-crossing ability.

Description

Technical Field

[0001] The present invention relates to the technical field of spherical robots, and particularly relates to a novel active unfolding spherical robot based on ratchets and pawls. Background Art

[0002] In recent years, mobile robots have been a leading industry that focuses on promoting innovative development. Traditional mobile robots are generally divided into wheeled robots, tracked robots, legged robots, etc. Wheeled robots and tracked robots are robots that move in continuous contact with the ground. When facing complex terrain tasks, they have poor stability and low movement efficiency. Legged robots have obvious characteristics of non - continuous support based on their movement forms, and there is great room for the development of their movement performance. However, they have relatively more degrees of freedom and higher control difficulty. Most existing robots are large in size because of their complex control systems and high energy requirements, and they cannot adapt to special environments.

[0003] Since the successful development of the first spherical robot in 1996, the development of spherical robots at home and abroad has always received high attention and continuous research. Among them, the spherical robot can install the actuator, power transmission mechanism and energy system in the internal space of the spherical shell, and has the following characteristics: 1) It has good static and dynamic stability. Because the spherical robot is spherical, when it encounters situations such as overturning and other abnormal movements, it can achieve rapid recovery through self - adjustment; 2) It has low energy consumption. The spherical robot requires less energy, the control system occupies less power, and its contact with the ground during movement is point contact, with less resistance; 3) It has a compact structure; 4) It has good environmental adaptability.

[0004] However, existing spherical robots generally have problems such as complex structures, weak obstacle - crossing abilities, and inability to cope with unstructured complex terrains. In addition, the installation methods of the movement mechanism and the driving mechanism of existing spherical robots are relatively single, all using fixed connections and unable to deform. The movement radius of the spherical robot does not change, so its movement mode is also relatively single, which further makes the spherical robot have a weak obstacle - crossing ability and inability to cope with complex terrains. Summary of the Invention

[0005] To overcome the defects of the prior art, the purpose of the present invention is to provide an active unfolding spherical robot based on ratchets and pawls, which overcomes the problems of existing spherical robots such as complex structures, single movement modes, weak obstacle - crossing abilities, and insufficient research on coping with unstructured complex terrains.

[0006] To this end, the present invention proposes an active deployable spherical robot based on ratchet pawl, comprising a frame, two hemispherical ball wheel mechanisms, and an deploying drive mechanism; the two ball wheel mechanisms are symmetrically arranged on both sides of the frame, and the two ball wheel mechanisms are respectively connected to the deploying drive mechanism; the deploying drive mechanism comprises a main shaft, a lateral deploying drive mechanism and a rotation drive mechanism; the ball wheel mechanisms each comprise an inner end ball wheel assembly, a three-impeller deformation mechanism and an outer end ball wheel assembly, the three being respectively arranged on the main shaft, the inner end ball wheel assembly being transmission connected to the rotation drive mechanism, and being connected to the main shaft through a linear bearing assembly one; the outer end ball wheel assembly is fixedly connected to the end of the main shaft, and the three-impeller deformation mechanism is slidingly connected to the main shaft through a linear bearing assembly two.

[0007] Among them, the lateral expansion drive mechanism drives the main shaft to move outward, so that the three-impeller deformation mechanism and the inner end ball wheel assembly and the outer end ball wheel assembly break away from the restriction relationship and expand radially, and the rotation drive mechanism then drives the three-impeller deformation mechanism to rotate circumferentially through the inner end ball wheel assembly, so that the entire robot can move forward.

[0008] Furthermore, the outer end ball wheel assembly includes an outer end flange and a limit bracket, and the outer end flange is fixed to the end of the main shaft; the limit bracket is arranged between the first shaft shoulder on the outer side of the main shaft and the outer end flange, and three limit pins are arranged on the limit bracket.

[0009] The three-impeller deformation mechanism includes a ratchet, three ratchet blades, three ratchet ball shells and a rotating bracket; the inner ends of the three ratchet blades are respectively rotatably connected to the rotating bracket through pins and Z-shaped torsion springs, and the three ratchet blades are distributed in a ring array, and the ratchet blades are fixedly connected to the ratchet ball shells; and three limit holes are provided on the rotating bracket, which are plugged into and cooperated with the limit pins to limit the deployment of the three-impeller deformation mechanism.

[0010] The inner end ball wheel assembly includes a driving outer wheel and a three-petal outer wheel spherical shell. The outer wheel spherical shell is located on the outside of the driving outer wheel and is fixedly connected to the driving outer wheel through an ear plate. The driving outer wheel is connected to the main shaft through a linear bearing assembly and also cooperates with the transmission bevel gear spline in the rotary drive mechanism.

[0011] The lateral expansion drive mechanism drives a pair of main shafts to move outward, so that the limit pin is disengaged from the limit hole, and then the pawl blade and the pawl ball shell are radially expanded under the action of the Z-shaped torsion spring and mesh with the ratchet teeth on the ratchet.

[0012] Among them, the driving outer wheel and the ratchet are connected by three hexagonal studs; the rotary drive mechanism drives the driving outer wheel and the ratchet to rotate, and then drives the ratchet ball shell to rotate circumferentially, so that the entire robot can move forward.

[0013] Furthermore, the rotation drive mechanism includes two drive motors, two drive bevel gears, and two transmission bevel gears; wherein, the output shaft of the drive motor is fixedly connected to the drive bevel gear through a steering wheel; the drive outer wheel is connected to the transmission bevel gear through a spline.

[0014] Furthermore, the lateral expansion drive mechanism includes a lateral expansion motor, a rack and pinion mechanism, and a push plate; the rack and pinion mechanism includes a gear and a pair of racks; the lateral expansion motor is fixedly connected to the gear through a steering wheel; the two racks are symmetrically installed on the upper and lower sides of the gear, and the push plate is connected to the main shaft through a D-shaped shaft circlip and a shaft retaining ring.

[0015] Furthermore, four guide rods are designed on the push plate, and the guide rods are inserted into the inside of the rack and are slidably connected to the rack.

[0016] Furthermore, the linear bearing assembly II includes an outer bearing sleeve, a shaft circlip, and a deep groove ball bearing; a circlip groove is provided in the through hole in the axial direction of the rotating bracket, and the shaft circlips on the rotating bracket and the outer bearing sleeve limit the displacement of the deep groove ball bearing on the main shaft in the outer direction. At the same time, the circlip on the circlip groove of the rotating bracket and the step of the outer bearing sleeve limit the displacement of the deep groove ball bearing in the inner direction, thereby realizing the circumferential movement of the rotating bracket.

[0017] Furthermore, a groove is formed on the outer side of the drive outer wheel, and a protrusion is provided on the inner side of the pawl blade. The groove formed on the outer side of the drive outer wheel is on the outer side of the protrusion of the pawl blade, restricting the outward movement of the pawl blade driven by the Z-shaped torsion spring.

[0018] Furthermore, the frame includes a frame plate, a frame bottom plate, two rack protection cases, two bevel gear frame plates, and two gear protection cases; the bevel gear frame plates are used to install the transmission bevel gears and are fixedly connected to the frame plate; the gear protection cases are in a half-bowl shape and are installed on the outer side of the transmission bevel gears.

[0019] Furthermore, the outer end ball wheel assembly further includes a connecting ball shell and an outer end ball shell. The outer end flange is fixedly connected to the outer end ball shell, and at the same time, the outer end ball shell is fixedly connected to the connecting ball shell.

[0020] Furthermore, a tail rod and a tail wheel are also connected to the rear end of the frame; the tail wheel is installed at the rear end of the tail rod and can rotate self.

[0021] The active expansion spherical robot based on ratchet and pawl provided by the present invention can be deformed and expanded through the setting of the three-blade deformation mechanism and the lateral expansion drive mechanism, forming a spherical structure with a larger walking radius; the spherical robot with the expansion ability can shrink into a sphere when in a scene where no obstacle crossing is required, improving the movement ability and quickly realizing the response; when encountering an obstacle, it can be actively expanded by using the ratchet and pawl, and the expanded spherical robot has the obstacle crossing ability.

[0022] In addition, this solution has the advantages of few driving units, low energy consumption, small volume, simple structure, strong obstacle-crossing ability, etc. It can realize the unfolding and deformation of the hemispherical wheels of the spherical robot, and improve the obstacle-crossing ability of the spherical robot by expanding the radius of the spherical wheels. It is an important research field for the innovation of the leg configuration of spherical robots.

[0023] In addition to the purposes, features, and advantages described above, this application has other purposes, features, and advantages. The following will refer to the drawings for a further detailed description of this application. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] The accompanying drawings forming a part of this application are used to provide a further understanding of this application. The schematic embodiments of this application and their descriptions are used to explain this application and do not constitute an improper limitation of this application. In the drawings:

[0025] Figure 1 is a schematic structural diagram of the active unfolding spherical robot of the present invention when not unfolded;

[0026] Figure 2 is a schematic structural diagram of the active unfolding spherical robot of the present invention when unfolded;

[0027] Figure 3 is a partial cross-sectional view of the active unfolding spherical robot of the present invention when not unfolded;

[0028] Figure 4 is a top view of the active unfolding spherical robot of the present invention when unfolded;

[0029] Figure 5 is a structural diagram of the three-impeller deformation mechanism of the active unfolding spherical robot of the present invention when unfolded;

[0030] Figure 6 is a schematic structural diagram of the unfolding drive mechanism of the active unfolding spherical robot of the present invention;

[0031] Figure 7 is a schematic structural diagram of the bearing assembly of the active unfolding spherical robot of the present invention;

[0032] Figure 8 is an exploded view of the outer end spherical wheel assembly of the active unfolding spherical robot of the present invention;

[0033] Figure 9 is an exploded view of the three-impeller deformation mechanism of the active unfolding spherical robot of the present invention;

[0034] Figure 10 is an exploded view of the inner end spherical wheel assembly of the active unfolding spherical robot of the present invention;

[0035] Figure 11Explosion diagram of the cooperation between the driving outer wheel and the transmission bevel gear in the active deployment spherical robot of the present invention;

[0036] Figure 12 Structural diagram of the bevel gear frame plate in the active deployment spherical robot of the present invention;

[0037] Explanation of reference numerals

[0038] 1. Frame plate; 2. Frame bottom plate; 3. Outer wheel spherical shell; 4. Connecting spherical shell; 5. Tail rod; 6. Tail wheel; 7. Outer end spherical shell; 8. Transverse deployment motor; 9. Gear protection shell; 10. Driving motor; 11. Bevel gear frame plate; 12. Push plate; 13. Main shaft; 14. Driving outer wheel; 141. Hexagon stud; 142. Ear plate; 15. Limit bracket; 151. Limit pin; 16. Rubber pad 1; 17. Pawl spherical shell; 18. Pawl blade; 19. Ratchet; 20. Rack; 21. Gear; 22. Guide rod; 23. Driving bevel gear; 24. Transmission bevel gear; 25. Axial retaining ring;

[0039] 26. D-shaped shaft circlip; 27. Cage; 28. Outer side bearing sleeve; 29. Shaft circlip; 30. Deep groove ball bearing; 31. Thrust needle roller bearing; 32. Z-shaped torsion spring; 33. Outer end flange; 34. Gear-rack mechanism; 35. Linear bearing assembly 1; 36. Linear bearing assembly 2; 37. Rubber ring; 38. Rack protection shell; 39. Transverse deployment drive mechanism; 40. Rotary drive mechanism; 42. Three-impeller deformation mechanism; 43. Rotary bracket. Detailed implementation manners

[0040] It should be noted that, without conflict, the embodiments in the present application and the features in the embodiments can be combined with each other. The present application will be described in detail below with reference to the drawings and in combination with the embodiments.

[0041] As Figures 1 to 12 shown, an active deployment spherical robot based on ratchet and pawl includes a frame, two hemispherical ball wheel mechanisms, and a deployment drive mechanism; the two ball wheel mechanisms are symmetrically arranged on both sides of the frame, and the two ball wheel mechanisms and the deployment drive mechanism are respectively connected.

[0042] Among them, the unfolding drive mechanism includes a main shaft 13, a lateral unfolding drive mechanism 39, and a rotation drive mechanism 40; the ball wheel mechanisms each include an inner end ball wheel assembly, a three-blade deformation mechanism 42, and an outer end ball wheel assembly, which are respectively arranged on the main shaft 13. The inner end ball wheel assembly is in transmission connection with the rotation drive mechanism 40 and is connected to the main shaft 13 through a first linear bearing assembly 35; the outer end ball wheel assembly is fixedly connected to the end of the main shaft 13, and the three-blade deformation mechanism 42 is slidably connected to the main shaft 13 through a second linear bearing assembly 36. The lateral unfolding drive mechanism 39 drives the main shaft 13 to move outward, causing the three-blade deformation mechanism 42 to radially unfold by disengaging from the inner end ball wheel assembly and the outer end ball wheel assembly, and then the rotation drive mechanism 40 drives the three-blade deformation mechanism 42 to rotate circumferentially through the inner end ball wheel assembly, enabling the entire robot to move forward.

[0043] Specifically, as Figure 3 , Figure 8 shown, the outer end ball wheel assembly includes an outer end flange 33, a limit bracket 15, a connecting ball shell 4, and an outer end ball shell 7. The outer end flange 33 is fixedly connected to the end of the main shaft 13 by screwing; the outer end flange 33 is directly fixedly connected to the outer end ball shell 7 using screws, and at the same time, the outer end ball shell 7 is fixedly connected to the connecting ball shell 4 using screws, forming an outer end fixedly connected whole, enabling the outer end fixedly connected whole to move along the X-axis direction with the main shaft 13.

[0044] The limit bracket 15 is located inside the connecting ball shell 4. Three limit pins 151 are provided at one end of the inner side of the limit bracket 15; the end of the limit bracket 15 without the limit pins 151 is in direct contact with the outer end flange 33, and the end of the limit bracket 15 with the limit pins 151 is in direct contact with the first shoulder on the outside of the main shaft 13, constituting a restriction on the circumferential rotation of the limit bracket 15 along the main shaft 13.

[0045] In addition, a first rubber pad 16 is provided between the outer end ball shell 7 and the connecting ball shell 4 to achieve a shock absorption effect and reduce the collision between the outer end ball shell 7 and the outer end flange 33.

[0046] As Figure 5 , Figure 9 shown, the three-blade deformation mechanism 42 includes a ratchet 19, three pawl blades 18, three pawl ball shells 17, and a rotating bracket 43; one end of the inner side of the three pawl blades 18 is respectively rotationally connected to the rotating bracket 43 through pins and Z-shaped torsion springs 32, and the three pawl blades 18 are annularly arrayed. The pawl blades 18 are fixedly connected to the pawl ball shells 17 using screws.

[0047] Among them, the rotating bracket 43, the Z-shaped torsion spring 32, and the pawl blade 18 are connected by a pin; one end of the Z-shaped torsion spring 32 is inserted into the positioning hole on the rotating bracket 43, and the other end is inserted into the positioning hole on the pawl blade 18; the Z-shaped torsion spring 32 is a 180° torsion spring and is compressed in the unexpanded state.

[0048] As Figure 3 , Figure 10 , Figure 11 shown, the inner end ball wheel assembly includes a driving outer wheel 14, a cage 27, and a three-piece outer wheel ball shell 3. The outer wheel ball shell 3 is located outside the driving outer wheel 14 and is fixedly connected to the driving outer wheel 14 through an ear plate 142; the driving outer wheel 14 is connected to the main shaft 13 through a linear bearing assembly one 35; among them, a groove is formed on the outside of the driving outer wheel 14, and a protrusion is provided on the inner side of the pawl blade 18. The groove formed on the outside of the driving outer wheel 14 is on the outside of the cage 27 and the protrusion of the pawl blade, restricting the outward movement of the torsion spring-driven pawl. In addition, the cage 27 is arranged inside the outer end of the driving outer wheel 14 to ensure the lateral stiffness of the pawl blade 18 and the torsion spring. A rubber ring 37 is provided between the outer wheel ball shell 3 and the driving outer wheel 14 to play a sealing role.

[0049] In addition, as Figure 7 shown, the linear bearing assembly two 36 includes an outer bearing sleeve 28, a shaft retaining ring 29, and a deep groove ball bearing 30; a retaining ring groove is provided in the through hole in the axial direction of the rotating bracket 43. The shaft retaining ring 29 on the rotating bracket 43 and the outer bearing sleeve 28 restrict the lateral displacement of the deep groove ball bearing 30 on the main shaft 13. At the same time, the retaining ring on the retaining ring groove of the rotating bracket 43 and the step of the outer bearing sleeve 28 restrict the inward displacement of the deep groove ball bearing 30, thereby realizing the circumferential movement of the rotating bracket 43; in addition, there is a sliding bearing with a fixed displacement inside the outer bearing sleeve 28 to reduce the friction during the left and right sliding of the rotating bracket 43 on the main shaft 13.

[0050] In order to restrict the automatic deployment of the three-impeller deformation mechanism 42, three limiting holes are provided on the rotating bracket 43; there are three limiting pins 151 on the limiting bracket 15; the limiting holes can be inserted and matched with the limiting pins 151 to prevent the three-impeller deformation mechanism 42 from being deployed. The three limiting holes on the rotating bracket 43 are correspondingly connected to the three limiting pins 151 on the limiting bracket. When the main shaft 13 drives the limiting bracket to move laterally, the limiting pins 151 move out of the limiting holes, thereby releasing the constraint on the circumferential rotation of the rotating bracket 43 along the main shaft 13.

[0051] When the three - impeller deformation mechanism 42 needs to be deployed, the lateral deployment drive mechanism 39 drives a pair of main shafts 13 to move outward. At this time, the outer - end flange 33, the outer - end spherical shell 7, the connecting spherical shell 4, and the limit bracket 15 fixedly connected to the main shaft 13 move outward a small distance, so that the three limit pins 151 on the limit bracket 15 are disengaged from the three limit holes on the rotating bracket 43, further making the circumferential rotation of the rotating bracket 43 unrestricted; the main shaft 13 continues to move outward, and the second shoulder in the main shaft 13 abuts against the linear bearing assembly 35 at the center position of the rotating bracket 43, pushing the rotating bracket 43 and the three - impeller deformation mechanism 42 to move outward, so that the protrusion inside the pawl blade 18 is disengaged from the outer edge of the driving outer wheel 14. The pawl blade 18 and the pawl spherical shell 17 are radially deployed under the action of the Z - shaped torsion spring 32 and engage with the ratchet teeth on the ratchet 19.

[0052] Specifically, as Figure 4 , Figure 10 , Figure 11 shown, the driving outer wheel 14 and the ratchet 19 are connected by three hexagon studs 141; and one end of the inner side of the driving outer wheel 14 is in spline fit with the transmission bevel gear 24 in the rotation drive mechanism 40. The rotation drive mechanism 40 drives the driving outer wheel 14 to rotate, and the ratchet 19 rotates together with the driving outer wheel 14. Then the ratchet 19 cooperates with the pawl blade 18 to drive the pawl spherical shell 17 to rotate circumferentially, enabling the entire robot to move forward.

[0053] As Figure 6 shown, the rotation drive mechanism 40 includes two drive motors 10, two drive bevel gears 23, and two transmission bevel gears 24; among them, the output shaft of the drive motor 10 is fixedly connected to the drive bevel gear 23 through a steering wheel; the drive motors 10, the transmission bevel gears 24, and the drive bevel gears 23 are symmetrically distributed and installed at the tail of the deformable spherical robot; the driving outer wheel 14 is connected to the transmission bevel gear 24 by splines, so that the drive bevel gear 23 can drive the driving outer wheel 14 to rotate circumferentially along the main shaft 13.

[0054] As Figure 6 shown, the lateral deployment drive mechanism 39 includes a lateral deployment motor 8, a rack - and - pinion mechanism 34, and a push plate 12; among them, the rack - and - pinion mechanism 34 includes a gear 21 and a pair of racks 20. The lateral deployment motor 8 is installed at the head of the robot, and the lateral deployment motor 8 is fixedly connected to the gear 21 through a steering wheel; the two racks 20 are symmetrically installed on the upper and lower sides of the gear 21. Four guide rods 22 are designed on the push plate 12, and the guide rods 22 are inserted into the inside of the racks 20 and are slidably connected to the racks 20; the push plate 12 is connected to the main shaft 13 through a D - shaped shaft snap ring 26 and a shaft retaining ring 25.

[0055] The horizontal expansion motor 8 rotates to drive the gear 21 to rotate, and at the same time drives the rack 20 to move along the direction of the main shaft 13, and further transmits the power to the main shaft 13 through the push plate 12; wherein, the guide rod 22 can prevent the deflection of components caused by the torque generated during the non-coaxial transmission process.

[0056] In this case, the frame includes a frame plate 1, a frame bottom plate 2, two rack protection cases 38, two bevel gear frame plates 11, and two gear protection cases 9; the frame plate 1 and the frame bottom plate 2 are connected by nuts, and the horizontal expansion motor 8 and the drive motor 10 are respectively fixedly installed between the frame plate 1 and the frame bottom plate 2.

[0057] The bevel gear frame plate 11 is used to install the transmission bevel gear 24 and is fixedly connected to the frame plate 1 by nuts (as Figure 12 shown); the lower end of the rack protection case 38 is directly installed on the frame plate 1, and at the same time the rack protection case 38 is arranged outside the rack 20 to play a horizontal guiding role; the gear protection case 9 is in a half-bowl shape and is installed outside the transmission bevel gear 24.

[0058] Among them, the drive outer wheel 14 and the bevel gear frame plate 11 are spaced by a flat thrust needle bearing 31 to reduce the friction between the drive outer wheel 14 and the bevel gear frame plate 11 during rotation; in addition, a flat thrust needle bearing 31 is also installed between the frame plate 1 and the drive bevel gear 23.

[0059] As Figure 1 、 Figure 2 shown, a tail rod 5 and a tail wheel 6 are also connected to the rear end of the frame; the tail wheel 6 is installed at the rear end of the tail rod 5 and can rotate freely; by setting the tail rod 5, the tail wheel 6 to cooperate with the outer wheel spherical shell 3 or the pawl spherical shell 17, the stability of the entire robot can be improved.

[0060] The working principle and working process of the active expansion spherical robot based on ratchet and pawl of the present invention are briefly described below with reference to the accompanying drawings.

[0061] When the spherical robot walks at a low speed or walks on a flat road surface and does not need to cross obstacles, the horizontal expansion drive mechanism does not work, and the entire spherical robot is in a spherical state; at this time, in the rotation drive mechanism 40, the drive motor 10 drives the drive outer wheel 14 to rotate through the drive bevel gear 23 and the transmission bevel gear 24, and the drive outer wheel 14 then drives the outer wheel spherical shell 3, the outer end spherical wheel assembly and the three-impeller deformation mechanism 42 in the unfolded state to rotate continuously, so that the entire robot can move forward.

[0062] When the spherical robot walks at high speed or walks on unstructured complex terrains and needs to cross obstacles, the lateral expansion drive mechanism starts to work and the whole spherical robot is in the expanded state. At this time, the lateral expansion motor 8 drives a pair of main shafts 13 to move outwards through the gear-rack mechanism 34 and the push plate 12. At this time, the outer flange 33, the outer spherical shell 7, the connecting spherical shell 4, and the limit bracket 15 fixedly connected to the main shaft 13 move outwards a small distance, so that the three limit pins 151 on the limit bracket 15 are disengaged from the three limit holes on the rotating bracket 43, further making the circumferential rotation of the rotating bracket 43 unrestricted.

[0063] The main shaft 13 continues to move outwards. The second shoulder in the main shaft 13 abuts against the linear bearing assembly two at the center position of the rotating bracket 43, pushing the rotating bracket 43 and the three-impeller deformation mechanism 42 to move outwards, so that the groove inside the ratchet pawl spherical shell 17 is disengaged from the outer edge of the driving outer wheel 14. The ratchet pawl blades 18 and the ratchet pawl spherical shell 17 are radially expanded under the action of the Z-shaped torsion spring 32 and are engaged with the ratchet teeth on the ratchet wheel 19 (as Figure 4 shown).

[0064] After the three-impeller deformation mechanism 42 is expanded, the driving motor 10 drives the driving outer wheel 14 to rotate through the driving bevel gear 23 and the transmission bevel gear 24. The driving outer wheel 14 drives the ratchet wheel 19 to rotate, and the ratchet wheel 19 drives the three ratchet pawl blades 18 and the three ratchet pawl spherical shells 17 to rotate circumferentially, enabling the whole robot to move forward.

[0065] The present invention discloses an actively expandable spherical robot based on ratchet and pawl, belonging to the field of spherical robots. When the robot moves in the spherical state, the outer spherical shell of the wheel and the ratchet wheel rotate synchronously. Under the constraint of the outer spherical shell of the wheel, the three ratchet pawl impellers maintain a circular shape with heads and tails connected and do not generate any movement.

[0066] When expanding, the lateral expansion drive mechanism drives the rotating bracket and the limit bracket to generate lateral movement. The ratchet pawl impeller is disengaged from the constraint of the outer spherical shell of the wheel, and at the same time, the limit bracket releases the locking effect on the rotating bracket. The energy stored by the compression of the Z-shaped torsion spring is released, driving the ratchet pawl impeller to rotate around the shaft on the cage. At the same time, the ratchet wheel also reaches the horizontal position of the ratchet pawl impeller under the action of the lateral expansion drive mechanism. The ratchet pawl impeller continues to rotate and comes into contact with the ratchet wheel, starting to engage. The ratchet wheel continues to rotate under the action of the driving motor, and the engaging section of the ratchet pawl impeller continues to slide on the ratchet teeth until full engagement, at which time this structure is fully expanded. After full engagement, the rotation of the ratchet wheel and the fixed outer wheel will be transmitted to the ratchet pawl impeller through the engagement, driving the overall rotation of the ratchet pawl impeller.

[0067] This solution has the advantages of small number of drives, low energy consumption, small size, simple structure, and strong obstacle surmounting ability. It can realize the expansion and deformation of the hemispherical wheels of the spherical robot and improve the obstacle surmounting ability of the spherical robot by expanding the radius of the spherical wheels. It is an important research field for innovation of the leg configuration of spherical robots.

[0068] In addition, in the preferred embodiment of the present invention, through reasonable mechanism design and the use of a variety of standard parts (bearing assemblies, retaining springs, etc.), while ensuring that the structure can work as set, this design also effectively eliminates the lateral movement of the main shaft and the friction of components such as the driving outer wheel and pawl in the turnover movement, thereby improving the feasibility and reliability of the overall movement of the mechanism.

[0069] The above description is only the preferred embodiment of the present application and is not intended to limit the present application. For those skilled in the art, the present application may have various modifications and variations. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present application shall be included in the protection scope of the present application.

Claims

1. An active unfolding spherical robot based on ratchet and pawl, characterized in that, It includes a frame, two hemispherical ball wheel mechanisms, and an unfolding drive mechanism; the two ball wheel mechanisms are symmetrically arranged on both sides of the frame, and the two ball wheel mechanisms are respectively connected to the unfolding drive mechanism; The unfolding drive mechanism includes a main shaft (13), a lateral unfolding drive mechanism (39) and a rotation drive mechanism (40); each ball wheel mechanism includes an inner end ball wheel assembly, a three-blade deformation mechanism (42) and an outer end ball wheel assembly, which are respectively arranged on the main shaft (13). The inner end ball wheel assembly is in transmission connection with the rotation drive mechanism (40) and is connected to the main shaft (13) through a linear bearing assembly one (35); the outer end ball wheel assembly is fixedly connected to the end of the main shaft (13), and the three-blade deformation mechanism (42) is slidably connected to the main shaft (13) through a linear bearing assembly two (36); Wherein, the lateral unfolding drive mechanism (39) drives the main shaft (13) to move outwards, so that the three-blade deformation mechanism (42) is disengaged from the inner end ball wheel assembly and the outer end ball wheel assembly and radially unfolds, and then the rotation drive mechanism (40) drives the three-blade deformation mechanism (42) to rotate circumferentially through the inner end ball wheel assembly, enabling the entire robot to move forward.

2. The active deployment spherical robot based on ratchet and pawl according to claim 1, wherein The outer end ball wheel assembly includes an outer end flange (33) and a limit bracket (15). The outer end flange (33) is fixedly connected to the end of the main shaft (13); the limit bracket (15) is arranged between the first shoulder on the outer side of the main shaft (13) and the outer end flange (33), and three limit pins (151) are provided on the limit bracket (15); The three-blade deformation mechanism (42) includes a ratchet wheel (19), three pawl blades (18), three pawl ball shells (17) and a rotation bracket (43); one end of the inner side of the three pawl blades (18) is respectively rotatably connected to the rotation bracket (43) through a pin and a Z-shaped torsion spring (32), and the three pawl blades (18) are annularly arrayed. The pawl blades (18) are fixedly connected to the pawl ball shells (17); three limit holes are provided on the rotation bracket (43) and are inserted and matched with the limit pins (151) to limit the unfolding of the three-blade deformation mechanism (42); The inner end ball wheel assembly includes a driving outer wheel (14) and a three-lobe outer wheel ball shell (3). The outer wheel ball shell (3) is located outside the driving outer wheel (14) and is fixedly connected to the driving outer wheel (14) through an ear plate (142). The driving outer wheel (14) is connected to the main shaft (13) through a linear bearing assembly one (35) and is also in spline fit with a transmission bevel gear (24) in the rotation drive mechanism (40); The lateral unfolding drive mechanism (39) drives a pair of main shafts (13) to move outwards, so that the limit pins (151) are disengaged from the limit holes, and further enables the pawl blades (18) and the pawl ball shells (17) to radially unfold under the action of the Z-shaped torsion spring (32) and mesh with the ratchet teeth on the ratchet wheel (19); Among them, the driving outer wheel (14) is connected to the ratchet wheel (19) by three hexagon studs (141); the rotary driving mechanism (40) drives the driving outer wheel (14) and the ratchet wheel (19) to rotate, and then drives the ratchet ball shell (17) to rotate circumferentially, so that the whole robot can move forward.

3. The active deployment spherical robot based on ratchet and pawl according to claim 2, wherein The rotary driving mechanism (40) includes two driving motors (10), two driving bevel gears (23), and two transmission bevel gears (24); among them, the output shaft of the driving motor (10) is fixedly connected to the driving bevel gear (23) through a steering wheel; the driving outer wheel (14) is connected to the transmission bevel gear (24) by a spline.

4. The active deployment spherical robot based on ratchet and pawl according to claim 2, wherein The lateral unfolding driving mechanism (39) includes a lateral unfolding motor (8), a rack and pinion mechanism (34), and a push plate (12); and the rack and pinion mechanism (34) includes a gear (21) and a pair of racks (20); The lateral unfolding motor (8) is fixedly connected to the gear (21) through a steering wheel; the two racks (20) are symmetrically installed on the upper and lower sides of the gear (21), and the push plate (12) is connected to the main shaft (13) through a D-shaped shaft circlip (26) and a shaft retaining ring (25).

5. The active deployment spherical robot based on ratchet and pawl according to claim 4, characterized in that, Four guide rods (22) are designed on the push plate (12), and the guide rods (22) are inserted into the inside of the rack (20) and are slidably connected to the rack (20).

6. The active deployment spherical robot based on ratchet and pawl according to claim 2, wherein The linear bearing assembly II (36) includes an outer bearing sleeve (28), a shaft circlip (29), and a deep groove ball bearing (30); a circlip groove is provided in the through hole in the axial direction of the rotary bracket (43), and the shaft circlip (29) on the rotary bracket (43) and the outer bearing sleeve (28) limit the displacement of the deep groove ball bearing (30) on the main shaft (13) to the outer side. At the same time, the circlip on the circlip groove of the rotary bracket (43) and the step of the outer bearing sleeve (28) limit the displacement of the deep groove ball bearing (30) to the inner side, so as to realize the circumferential movement of the rotary bracket (43).

7. The active deployment spherical robot based on ratchet and pawl according to claim 2, characterized in that, The groove formed on the outside of the driving outer wheel (14), the pawl blade (18) has a protrusion, and the groove formed on the outside of the driving outer wheel (14) is outside the protrusion of the pawl blade, restricting the outward movement of the Z-shaped torsion spring (32) driving the pawl blade (18).

8. The active deployment spherical robot based on ratchet and pawl according to claim 3, characterized in that, The frame includes a frame plate (1), a frame bottom plate (2), two rack protection cases (38), two bevel gear frame plates (11), and two gear protection cases (9); The bevel gear frame plate (11) is used for installing the transmission bevel gear (24) and is fixedly connected to the frame plate (1); the gear protection case (9) is in a half-bowl shape and is installed on the outside of the transmission bevel gear (24).

9. The active deployment spherical robot based on ratchet and pawl according to claim 2, characterized in that, The outer end ball wheel assembly further includes a connecting ball shell (4) and an outer end ball shell (7), the outer end flange (33) is fixedly connected to the outer end ball shell (7), and at the same time the outer end ball shell (7) is fixedly connected to the connecting ball shell (4).

10. The active deployment spherical robot based on ratchet and pawl according to any one of claims 1 to 9, characterized in that, A tail rod (5) and a tail wheel (6) are further connected to the rear end of the frame; the tail wheel (6) is installed at the rear end of the tail rod (5) and can rotate self.

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