CN114347058A - Double-motion mode robot - Google Patents
Double-motion mode robot Download PDFInfo
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- CN114347058A CN114347058A CN202210023653.6A CN202210023653A CN114347058A CN 114347058 A CN114347058 A CN 114347058A CN 202210023653 A CN202210023653 A CN 202210023653A CN 114347058 A CN114347058 A CN 114347058A
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- 239000000463 material Substances 0.000 claims description 22
- 210000000548 hind-foot Anatomy 0.000 claims description 15
- 210000004744 fore-foot Anatomy 0.000 claims description 12
- 230000009977 dual effect Effects 0.000 claims description 9
- 239000013013 elastic material Substances 0.000 claims description 4
- 230000009191 jumping Effects 0.000 abstract description 21
- 230000007613 environmental effect Effects 0.000 abstract description 4
- 230000000694 effects Effects 0.000 description 13
- 230000008855 peristalsis Effects 0.000 description 12
- 230000005484 gravity Effects 0.000 description 7
- 230000002572 peristaltic effect Effects 0.000 description 6
- 229920001296 polysiloxane Polymers 0.000 description 5
- 230000005540 biological transmission Effects 0.000 description 4
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- 238000010168 coupling process Methods 0.000 description 3
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- 229910002027 silica gel Inorganic materials 0.000 description 3
- 230000001154 acute effect Effects 0.000 description 2
- 238000011065 in-situ storage Methods 0.000 description 2
- 238000009434 installation Methods 0.000 description 2
- 230000001737 promoting effect Effects 0.000 description 2
- 229920002379 silicone rubber Polymers 0.000 description 2
- 230000009286 beneficial effect Effects 0.000 description 1
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- 238000013461 design Methods 0.000 description 1
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- 210000005010 torso Anatomy 0.000 description 1
- 238000013519 translation Methods 0.000 description 1
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Abstract
The invention relates to a robot with double motion modes, which comprises a bendable trunk, a pneumatic bending driver and a pneumatic bounce driver, wherein the bendable trunk is connected with the pneumatic bending driver; the front end of the bendable trunk is fixedly connected with a front foot, the rear end of the bendable trunk is fixedly connected with a rear foot, and the landing positions of the front foot and the rear foot determine a reference plane; two ends of the pneumatic bending driver are respectively fixedly connected with two ends of the bendable trunk; the pneumatic bounce drive is rigidly connected to the bendable torso with its lowest point movable from above the datum level to below the datum level. The robot with the double motion modes has the creeping mode and the jumping mode, the creeping mode is convenient for the robot with the double motion modes to move in an environment with good road conditions, and the jumping mode is convenient for the robot with the double motion modes to move in an environment with obstacles, so that the robot with the double motion modes has good environmental adaptability.
Description
Technical Field
The invention relates to the technical field of movable double-motion-mode robots, in particular to a double-motion-mode robot.
Background
Compared with the traditional rigid robot made of metal materials, the soft robot made of the high-elasticity silicone rubber material has natural flexibility, environmental adaptability and safety, can realize new functions which are difficult to realize by the traditional rigid robot, can operate small objects accurately, can be driven by limited or complex space and multiple degrees of freedom, can work in non-structural environments better, and has great application prospects in the fields of disaster relief, military affairs and reconnaissance such as environmental exploration, structural inspection and information detection. However, the motion of the soft mobile robot generally depends on the self-deformation of the silicon rubber material, which also causes the current soft mobile robot to have the disadvantages of slow motion speed, single motion mode, and the like.
Patent document CN212445259U discloses a flexible trunk of a quadruped robot, comprising: the front driving gear is connected with the rear driving gear through a first connecting rod; the front trunk part and the rear trunk part are rotatably connected through a rotating shaft, wherein the axis of the rotating shaft extends along the left and right directions of the four-footed robot, and the left and right directions of the four-footed robot are defined as the directions which are vertical to the motion direction of the four-footed robot in the horizontal plane; the first driving motor is fixedly connected with the front trunk part, and the output end of the first driving motor is connected with the first driving gear; the second driving motor is fixedly connected with the rear trunk part, and the output end of the second driving motor is connected with a second driving gear; the first driving gear and the second driving gear are meshed with the driven gear; the driven gear is connected with the rotating shaft; the first driving motor drives the front trunk part and/or the second driving motor drives the rear trunk part to relatively curl or extend around the axis of the rotating shaft respectively. The robot moves in a mode that four feet drive the robot to move, and is only suitable for moving in an environment with good road conditions.
Patent document CN113319888A discloses a pneumatic soft robot capable of directionally bouncing, which includes a shell, the shell forms a cavity, the shell includes a bottom cover, the bottom cover is a hemispherical shell, the bottom cover is provided with a notch, the notch penetrates through the bottom cover, and the notch is asymmetric with respect to at least one symmetric plane of the bottom cover; in the natural state that the cavity is not inflated, the bottom cover is sunken into the cavity, the notch is in a closed state, and in the state that the cavity is inflated, the shell can jump suddenly and be unstable, and then the notch is opened. The robot moves in a bouncing mode, the bouncing direction of the robot is difficult to control, and the movement directivity is poor.
The south China university paper document 'a modularized design and research of a soft robot based on pneumatic drive' discloses a bending type pneumatic soft drive unit, which forms a soft drive by embedding a pneumatic grid (Pneu-nets). Such soft actuators are known as pneumatic mesh soft actuators, or multi-balloon flex actuators.
Disclosure of Invention
The invention aims to provide a double-motion mode robot to overcome the defect that the existing double-motion mode robot cannot give consideration to obstacle crossing capability and running direction control.
The technical scheme of the invention is as follows:
a dual motion mode robot comprises a bendable trunk, a pneumatic bending driver and a pneumatic bounce driver; the front end of the bendable trunk is fixedly connected with a front foot, the rear end of the bendable trunk is fixedly connected with a rear foot, and the landing positions of the front foot and the rear foot determine a reference plane; two ends of the pneumatic bending driver are respectively fixedly connected with two ends of the bendable trunk; the pneumatic bounce drive is rigidly connected to the bendable torso with its lowest point movable from above the datum level to below the datum level.
Preferably, still including installing gas accuse subassembly on the crooked type truck, pneumatic crooked driver is equipped with the crooked driver gas port, pneumatic bounce driver is equipped with the bounce driver gas port, gas accuse subassembly includes air pump, control treater, bending control solenoid directional valve and bounce control solenoid directional valve, bending control solenoid directional valve with crooked driver gas port pipeline intercommunication, bounce control solenoid directional valve with bounce driver gas port pipeline intercommunication, the output of control treater respectively with the control end of bending control solenoid directional valve, the control end of bounce control solenoid directional valve are connected. The pneumatic control assembly is arranged at the other position and is connected with the double-motion mode robot through the air pipe, and the moving range of the double-motion mode robot is limited by the length of the air pipe. When the pneumatic control assembly is installed on the bendable trunk, a power supply, such as a solar cell panel, a battery and the like, is arranged on the double-motion-mode robot, and the moving range of the double-motion-mode robot is not limited by the length of the air pipe any more but only limited by the power supply.
Further preferably, the pneumatic control assembly comprises a solar cell panel, and the solar cell panel is used for supplying power to the air pump, the control processor, the bending control electromagnetic directional valve and the bouncing control electromagnetic directional valve.
Preferably, pneumatic bounce driver includes outer hemisphere and interior hemisphere, the edge of outer hemisphere with the edge sealing connection of interior hemisphere be equipped with bounce driver gas port on the outer hemisphere, the outer hemisphere with interior hemisphere all adopts elastic material to make, just the elastic modulus of outer hemisphere is less the elastic modulus of interior hemisphere, the outer hemisphere respectively with the both ends of flexible type truck are hard-wired. The outer hemisphere is respectively and hard connected with the two ends of the bendable trunk, so that the outer hemisphere and the inner hemisphere are both made of elastic materials, and the pneumatic bounce driver has the minimum influence on the bending effect of the bendable trunk. Only the edge of the outer hemisphere is arranged to be in sealing connection with the edge of the inner hemisphere, so that an air cavity can be formed between the outer hemisphere and the inner hemisphere, and the other wall bodies of the outer hemisphere and the other wall bodies of the inner hemisphere are not in a constrained state. The elastic modulus of the outer hemisphere is smaller than that of the inner hemisphere, so that when the air port of the bounce driver inflates air to the air cavity between the outer hemisphere and the inner hemisphere, the wall body of the inner hemisphere can be bulged out of the outer hemisphere, and the bounce of the dual-motion mode robot is facilitated. In the bouncing process, the air cavity between the outer hemisphere and the inner hemisphere can be deflated through the air port of the bouncing driver, and the state that the inner hemisphere is expanded out of the outer hemisphere can also be maintained.
More preferably, the inner radius of the outer hemisphere is ROuter coverWith a thickness tOuter coverThe elastic modulus of the material is EOuter cover(ii) a The inner radius of the inner hemisphere is RInner partWith a thickness tInner partThe elastic modulus of the material is EInner part；
Setting through finite element simulation analysis
EInner part/EOuter coverWhen the height is 47 mm, the bounce height of the pneumatic bounce driver is the highest and is 100mm, and the pneumatic bounce driver is arranged
EInner part/EOuter coverThe bounce height of the pneumatic bounce driver is only 50mm when the vehicle is 47.
Further preferably, the outer hemisphere is made of a material having an elastic modulus of 50.9 to 91.4KPa, and the inner hemisphere is made of a material having an elastic modulus of 2.7 to 4.3 MPa. The bounce driver made of the material with the specification can balance the bounce height of the dual-motion mode robot and the adverse effect on the peristalsis of the dual-motion mode robot. Silicone material can be used for both the outer hemisphere and the inner hemisphere.
Preferably, the pneumatic bounce driver is provided with an upward bouncing line, the upward bouncing line is arranged on a traveling surface defined by the front foot and the rear foot, an included angle between the upward bouncing line and the reference surface is greater than or equal to 45 degrees and smaller than 90 degrees, and the upward bouncing line is arranged in front of a normal line of the reference surface. Therefore, when the pneumatic bounce driver works, the double-motion-mode robot can be driven to bounce forwards instead of vertically upwards in situ. After the inventor tests, when the upward bouncing ray is determined to be arranged on the traveling surface determined by the front foot and the rear foot, the included angle of 82 degrees is formed between the upward bouncing ray and the reference surface, and the upward bouncing ray is arranged in front of the normal line of the reference surface, the jumping mode of the double-motion mode robot is optimal, and the jumping height and the jumping distance can be considered at the same time.
Preferably, the bendable trunk comprises a front trunk part and a rear trunk part, the front trunk part and the rear trunk part are rotatably connected, and the pneumatic bounce driver is hard connected with the front trunk part, or the pneumatic bounce driver is hard connected with the rear trunk part. When the pneumatic bounce driver is rigidly connected only to the front torso member or the rear torso member, the pneumatic bounce driver does not affect the bending of the bendable torso member.
Preferably, the front foot and the rear foot both comprise a leg part and a toe, and the toe is arranged behind and below the leg part and forms an obtuse included angle with the leg part.
Preferably, the pneumatic bending driver comprises a pneumatic grid soft driver and a resetting piece, two ends of the pneumatic grid soft driver are respectively fixedly connected with two ends of the bendable trunk, and two ends of the resetting piece are respectively connected with two ends of the bendable trunk. The pneumatic grid soft driver has good deformation promoting effect, but when the pneumatic grid soft driver is in a straight state, the straightening effect on the bendable trunk is weak, and the resetting piece can improve the resetting speed of the bendable trunk.
Preferably, the bendable trunk includes a front trunk portion, a rear trunk portion, and a reverse bending limiting portion, the front trunk portion and the rear trunk portion are rotatably connected, the rotation axes of the front trunk portion and the rear trunk portion are arranged parallel to the reference plane, and the reverse bending limiting portion is fixedly connected to the front trunk portion and is used for limiting the reverse bending of the rear trunk portion relative to the front trunk portion, or the reverse bending limiting portion is fixedly connected to the rear trunk portion and is used for limiting the reverse bending of the front trunk portion relative to the rear trunk portion. The reverse bending of the front torso part relative to the rear torso part is limited by the reverse bending limiting part, and energy is saved more than the reverse bending of the front torso part relative to the rear torso part is limited by the pneumatic bending driver.
In the invention, the double-motion mode robot has a peristalsis mode and a jumping mode. Under the peristalsis mode, the front foot and the rear foot are in contact with the ground, and the pneumatic bending driver drives the front end and the rear end of the bendable trunk to be straightened and bent, so that the robot in the double-motion mode crawls. In the jumping mode, the lowest point of the pneumatic bouncing driver rapidly moves from being higher than the reference surface to being lower than the reference surface, and after the lowest point of the pneumatic bouncing driver is contacted with the ground, the double-motion mode robot is driven to jump, so that the jumping direction of the double-motion mode robot deviates from the gravity direction, and the double-motion mode robot can jump and travel. In designing the dual-motion modality robot of the present invention, attention is paid to: firstly, in the creeping mode, the pneumatic bounce driver does not influence the bending and straightening of the bendable trunk excessively, and the friction between the lowest point of the pneumatic bounce driver and the ground is avoided as much as possible; second, in the jumping mode, the jumping direction of the dual-motion-mode robot should be deviated from the gravity direction.
The invention has the beneficial effects that:
1. the robot with the double motion modes has the creeping mode and the jumping mode, the creeping mode is convenient for the robot with the double motion modes to move in an environment with good road conditions, and the jumping mode is convenient for the robot with the double motion modes to move in an environment with obstacles, so that the robot with the double motion modes has good environmental adaptability.
Drawings
Fig. 1 is an exploded view of a dual motion mode robot of the present invention, without a reset member.
Fig. 2 is a perspective view of fig. 1.
Fig. 3 is an exploded view of the bendable torso, forefoot, hindfoot and pneumatic control components of a dual motion modality robot of the present invention.
Fig. 4 is a perspective view of fig. 3.
Fig. 5 is an exploded view of the pneumatic jump drive of a dual motion mode robot of the present invention.
Fig. 6 is a first diagram illustrating a peristaltic mode advancing principle of the dual-motion mode robot according to the present invention.
Fig. 7 is a diagram for analyzing the peristaltic mode advancing principle of the dual-motion mode robot according to the present invention.
Fig. 8 is a size diagram of a pneumatic jump drive of a dual-motion mode robot of the present invention.
The reference numbers indicate that 1-bendable trunk, 11-front trunk, 111-reset piece setting groove A, 112-fixed rod A, 12-rear trunk, 121-reset piece setting groove B, 122-fixed rod B, 13-rotating shaft, 21-front foot, 22-rear foot, 3-pneumatic bending driver, 31-pneumatic grid soft driver, 32-fixed piece, 4-pneumatic bounce driver, 41-outer hemisphere, 42-inner hemisphere, 43-upper fixed ring, 44-lower fixed ring, 45-bounce driver air port, 5-pneumatic control component, 51-air pump, 52-air pipe joint row, 53-bending control electromagnetic directional valve, 54-bounce control electromagnetic directional valve and 55-control panel.
Detailed Description
The present invention is described below in terms of embodiments in conjunction with the accompanying drawings to assist those skilled in the art in understanding and implementing the present invention. Unless otherwise indicated, the following embodiments and technical terms therein should not be understood to depart from the background of the technical knowledge in the technical field.
Example 1: a dual-motion modality robot, see fig. 1-2, includes a bendable torso 1, a pneumatic bending drive 3, a pneumatic bounce drive 4, and a pneumatic control assembly 5. The front end of the bendable trunk 1 is fixedly connected with a front foot 21, the rear end of the bendable trunk 1 is fixedly connected with a rear foot 22, and the landing positions of the front foot 21 and the rear foot 22 determine a reference plane. Two ends of the pneumatic bending driver 3 are respectively fixedly connected with two ends of the bendable trunk 1. The pneumatic bounce driver 4 is hard connected with the bendable trunk 1, and the lowest point of the pneumatic bounce driver 4 can move from the upper part of the reference surface to the lower part of the reference surface.
The pneumatic bounce drive is mounted on the flexible torso 1 with upward bouncing rays. The direction of the upward bouncing line is determined by the counterforce which is given to the pneumatic bouncing driver by the ground surface and is driven by the pneumatic bouncing driver to the double-motion-mode robot and the resultant force of gravity of the double-motion-mode robot. When the elastic hook is used, an acute angle is formed between the upward elastic line and the gravity direction. Therefore, when the pneumatic bounce driver works, the double-motion-mode robot can be driven to bounce instead of vertically upwards in situ. Generally, the upward shot lines are arranged on the traveling surface determined by the front foot and the rear foot, and the upward shot lines are arranged in front of the normal line of the reference surface, so that the dual-motion mode robot still moves on the traveling surface when traveling in a jumping mode, does not deviate from the traveling surface, and is easy to control the motion track. According to estimation, the included angle between the upward bouncing ray and the reference plane can be set to be more than or equal to 45 degrees and less than 90 degrees, so that the pneumatic bouncing driver is mainly used for driving the double-motion-mode robot to jump high instead of moving forward when working.
In the invention, the double-motion mode robot has a peristalsis mode and a jumping mode. Under the peristalsis mode, the front foot and the rear foot are in contact with the ground, and the pneumatic bending driver drives the front end and the rear end of the bendable trunk to be straightened and bent, so that the robot in the double-motion mode crawls. In the jumping mode, the lowest point of the pneumatic bouncing driver rapidly moves from being higher than the reference surface to being lower than the reference surface, and after the lowest point of the pneumatic bouncing driver is contacted with the ground, the double-motion mode robot is driven to jump, so that the jumping direction of the double-motion mode robot deviates from the gravity direction, and the double-motion mode robot can jump and travel. In designing the dual-motion modality robot of the present invention, attention is paid to: firstly, in the creeping mode, the pneumatic bounce driver does not influence the bending and straightening of the bendable trunk excessively, and the friction between the lowest point of the pneumatic bounce driver and the ground is avoided as much as possible; second, in the jumping mode, the jumping direction of the dual-motion-mode robot should be deviated from the gravity direction.
One shape of the forefoot and hindfoot is: the front foot and the rear foot comprise leg parts and toe parts, the toe parts are arranged at the rear lower parts of the leg parts, and obtuse included angles are formed between the toe parts and the leg parts. Referring to fig. 6, in the initial state 1, the bendable trunk 1 is in a flat state; when the bendable trunk 1 is bent, the evolution 1a conforms to the peristaltic motion mode of the dual-motion mode robot, in the figure, the two-dot chain line indicates the shape and position of the dual-motion mode robot before peristalsis, and the thin solid line indicates the shape and position of the dual-motion mode robot after peristalsis. Evolution 1b does not correspond to the mode of peristaltic motion of a dual motion modality robot, as it cannot move backwards with the toe of the forefoot against the ground. In evolution 1a, the toe does not affect hindfoot anteversion during hindfoot anteversion. Referring to fig. 7, after the bendable trunk 1 is bent, the dual motion modality robot moves forward to a new position, i.e., the position of the initial state 2. When the bendable trunk 1 is restored to be straight, the evolution 2a conforms to the peristaltic motion mode of the dual-motion mode robot, in the figure, the two-dot chain line indicates the shape and position of the dual-motion mode robot before peristalsis, and the thin solid line indicates the shape and position of the dual-motion mode robot after peristalsis. Evolution 2b does not correspond to the mode of peristaltic motion of a dual motion modality robot, as it cannot move backwards with the toe of the hindfoot against the ground. In evolution 2a, during forefoot advancement, its toe does not affect forefoot advancement. With this analysis, the forefoot and the hindfoot in the flexible trunk of the four-legged robot disclosed in patent document CN212445259U are erroneous.
Yet another arrangement of the forefoot and hindfoot may be: the front foot is fixedly connected with a front foot rotating shaft, the front foot rotating shaft is rotatably connected with the bendable trunk 1, the front foot driving motor is fixed on the bendable trunk 1, and an output shaft of the front foot driving motor is in transmission connection with the front foot rotating shaft, preferably, the precise transmission connection is realized through a shaft coupling and a gear. The hind foot is fixedly connected with the hind foot rotating shaft, the hind foot rotating shaft is rotatably connected with the bendable trunk 1, the hind foot driving motor is fixed on the bendable trunk 1, the output shaft of the hind foot driving motor is in transmission connection with the hind foot rotating shaft, and the precise transmission connection is preferably realized through a shaft coupling and a gear. Therefore, the shapes of the front foot and the rear foot do not influence the peristalsis advance of the dual-motion mode robot.
Referring to fig. 1 to 4, in the present embodiment, bendable trunk 1 includes front trunk portion 11, rear trunk portion 12, and rotation shaft 13, front trunk portion 11 and rear trunk portion 12 are connected by rotation shaft 13 to realize rotatable connection of front trunk portion 11 and rear trunk portion 12, and rotation shaft 13 is disposed parallel to a reference plane.
To facilitate the hard coupling of the air bounce drive unit 4, two fixing rods a112 are fixed to the lower surface of the front body portion 11, and two fixing rods B122 are fixed to the lower surface of the rear body portion 12. To facilitate the placement of the restoring member, a restoring member placement groove a111 is provided in the front body portion 11, and a restoring member placement groove B121 is provided in the rear body portion 12.
It is to be understood that at least three points define a plane, or at least one point and a line define a plane. Referring to fig. 1, in the present embodiment, there are two front feet 21 and two rear feet 22, and the front feet 21 and the rear feet 22 are respectively disposed at four corners of the bendable trunk 1. Each forefoot is in contact with the ground line and each hind foot is in contact with the ground line, such that a reference plane can be determined. Of course, there may be one forefoot 21 and one rearfoot 22, and when the pneumatic bounce driver 4 is not in contact with the ground, the forefoot 21 and the rearfoot 22 may be sufficient as long as they can stably support the bendable trunk 1 and the attached device mounted thereon.
Referring to fig. 4, in this embodiment, the pneumatic control assembly 5 is mounted on the bendable trunk 1, the pneumatic bending driver 3 is provided with a bending driver air port (not shown), the pneumatic bounce driver 4 is provided with a bounce driver air port 45, the pneumatic control assembly 5 comprises an air pump 51, a control processor, a bending control electromagnetic directional valve 53, a bounce control electromagnetic directional valve 54 and a rechargeable battery (not shown), the bending control electromagnetic directional valve 53 and the bounce control electromagnetic directional valve 54 both select two-position three-way electromagnetic valves, an air outlet of the air pump 51 is communicated with an a port of a four-way pipe joint through a pipeline, a B port of the four-way pipe joint is communicated with a relief valve (not shown) through a pipeline, a C port of the four-way pipe joint is communicated with the a port of the bending control electromagnetic directional valve 53 through a pipeline, the B port of the bending control electromagnetic directional valve 53 is used as an air outlet, a Y port of the bending control electromagnetic directional valve 53 is communicated with the bending driver air port through a pipeline, the D port of the four-way pipe joint is communicated with the A port of the bounce control electromagnetic directional valve 54 through a pipeline, the B port of the bounce control electromagnetic directional valve 54 is used as an exhaust port, the Y port of the bounce control electromagnetic directional valve 54 is communicated with the bounce driver air port 45 through a pipeline, and the output end of the control processor is respectively and electrically connected with the control end of the bending control electromagnetic directional valve 53 and the control end of the bounce control electromagnetic directional valve 54. The rechargeable battery is used for supplying power to the air pump 51, the control processor, the bending control electromagnetic directional valve 53 and the bouncing control electromagnetic directional valve 54. The control processor is fixed to the control board 55. When the pneumatic control assembly is arranged on the bendable trunk, the moving range of the robot with the double moving modes is not limited by the length of the air pipe any more, but is limited only by the cruising ability of the rechargeable battery.
In other embodiments, the pneumatic control assembly 5 may not be installed on the dual-motion mode robot, and at this time, when the pneumatic control assembly 5 is connected with the dual-motion mode robot through the air pipe, the moving range of the dual-motion mode robot is limited by the length of the air pipe. Alternatively, the pneumatic control assembly 5 may be partially mounted on a dual motion mode robot.
In other embodiments, the rechargeable battery of the air control assembly 5 can be replaced by a battery compartment, and the battery is installed in the battery compartment during use. Alternatively, the rechargeable battery of the pneumatic control assembly 5 may be replaced by a solar panel, and the solar panel is used to supply power to the air pump 51, the control processor, the bending control electromagnetic directional valve 53 and the bouncing control electromagnetic directional valve 54.
Referring to fig. 1 and 5, in the present embodiment, the pneumatic bounce driver 4 includes an outer hemisphere 41, an inner hemisphere 42, an upper fixing ring 43, a lower fixing ring 44 and a bounce driver air port 45, the outer hemisphere 41 is provided with a flange a, the inner hemisphere 42 is provided with a flange B, the upper fixing ring 43 is disposed above the flange a, the lower fixing ring 44 is disposed below the flange B, the bounce driver air port 45 is disposed between the flange a and the flange B, the flange a, the flange B and the bounce driver air port 45 are hermetically connected to realize that the edge of the outer hemisphere is hermetically connected to the edge of the inner hemisphere, and an air cavity between the outer hemisphere 41 and the inner hemisphere 42 can only be communicated with the outside through the bounce driver air port 45. Only the edge of the outer hemisphere is arranged to be in sealing connection with the edge of the inner hemisphere, so that an air cavity can be formed between the outer hemisphere and the inner hemisphere, and the other wall bodies of the outer hemisphere and the other wall bodies of the inner hemisphere are not in a constrained state. In other embodiments, the bounce drive vents 45 may also be disposed on the outer hemisphere 41. The hard connection of the pneumatic bounce driver 4 and the front trunk 11 can be achieved by bolting the fixing rod a112, the upper fixing ring 43, the flange a, the flange B, and the lower fixing ring 44. The hard connection of the pneumatic bounce driver 4 to the rear trunk 12 can be achieved by bolting the fixing rod B122, the upper fixing ring 43, the flange a, the flange B, and the lower fixing ring 44. Since the outer hemisphere is hard-connected to both ends of the bendable trunk, respectively, the outer hemisphere 41 and the inner hemisphere 42 are made of elastic material, so that the pneumatic bounce driver has the least influence on the bending effect of the bendable trunk. In this embodiment, the upper fixing ring 43 and the lower fixing ring 44 are added to the pneumatic bounce driver 4, so that the upper fixing ring 43 and the lower fixing ring 44 are made of bendable materials to reduce the adverse effect of the pneumatic bounce driver 4 on bending of the bendable trunk. In this embodiment, the elastic modulus of the outer hemisphere 41 is set to be smaller than the elastic modulus of the inner hemisphere 42, so that when the air cavity between the outer hemisphere and the inner hemisphere is inflated through the air port of the bounce driver, the wall body of the inner hemisphere can be bulged out of the outer hemisphere, which is helpful for the dual-motion mode robot to bounce. In the bouncing process, the air cavity between the outer hemisphere and the inner hemisphere can be deflated through the air port of the bouncing driver, and the state that the inner hemisphere is expanded out of the outer hemisphere can also be maintained.
Because the outer hemispheres are respectively and rigidly connected with the two ends of the bendable trunk, in order to enable the upward elastic line to form an acute angle with the gravity direction, in the embodiment, the fixing rod A112 and the fixing rod B122 have the same structure, but the distance between the front foot and the rear foot is 110mm, and the front foot is shorter than the rear foot by more than 5mm, so that the included angle between the bendable trunk and the reference plane is not more than 87.397 degrees when the bendable trunk is straightened. After the inventor actually measures, when the bendable trunk is straightened, the included angle between the upward bouncing ray of the pneumatic bouncing driver 4 and the reference plane is set to be 82 degrees, the jumping mode of the double-motion mode robot is optimal, and the jumping height and the jumping distance can be considered.
In this embodiment, the lowest point of the pneumatic bounce driver is 5mm away from the reference surface.
In other embodiments, the pneumatic bounce driver 4 may be hard-wired to only the front torso member 11, or the pneumatic bounce driver 4 may be hard-wired to only the rear torso member 12. When the pneumatic bounce driver is rigidly connected only to the front torso member or the rear torso member, the pneumatic bounce driver does not affect the bending of the bendable torso member. When the pneumatic bounce drive 4 is hard-wired to the front torso 11 only, the upward bounce line of the pneumatic bounce drive 4 is affected by two factors simultaneously: firstly, when the bendable trunk is straightened, the upward bouncing ray of the pneumatic bouncing driver 4 forms an included angle with a reference plane; second, the angle of rotation of the front torso part 11 when the bendable torso bends. Since the rotation angle of the front trunk 11 is a range value when the bendable trunk is bent, the angle between the upward bouncing ray of the pneumatic bounce driver 4 and the reference plane is adjustable, and thus the obstacle crossing effect of the pneumatic bounce driver 4 is more excellent. Of course, this effect is also obtained when the pneumatic bounce driver 4 is only hard-wired to the rear torso part 12.
Let the inner radius of the outer hemisphere be ROuter coverWith a thickness tOuter coverThe elastic modulus of the material is EOuter cover(ii) a The inner radius of the inner hemisphere is RInner partWith a thickness tInner partThe elastic modulus of the material is EInner part(ii) a In the present embodiment, the first and second electrodes are,
Einner part/EOuter cover47. Of course,
the bouncing effect of the pneumatic bouncing driver is still very good.
In this embodiment, R is setOuter cover＝53.5mm，tOuter cover＝3mm，RInner part＝52.33mm，tInner part2mm, cross section of the outer hemisphere 1The arc angle is 180 degrees, the arc angle of the cross section of the inner hemisphere 2 is 164 degrees, the outer hemisphere is made of silica gel with the elastic modulus of 74KPa, the inner hemisphere is made of silica gel with the elastic modulus of 3.48MPa, and the setting is carried out through finite element simulation analysis
EInner part/EOuter coverWhen the height is 47 mm, the bounce height of the pneumatic bounce driver is the highest and is 100mm, and the pneumatic bounce driver is arranged
EInner part/EOuter coverThe bounce height of the pneumatic bounce driver is only 50mm when the vehicle is 47. Specifically, to understand the mechanical response of the bouncer in depth, Finite Element (FE) simulations were performed using the commercial software package ABAQUS 2020 standard. In the finite element modeling analysis, the radius ratio between the two hemispheres and the thickness ratio and the material were simulated for the best driver size results. By comparing the influence of the radius ratio and thickness ratio of different elastic moduli of the inner hemisphere and the outer hemisphere on the bounce effect, the method obtains thatInner part/tInner part)/(ROuter cover/tOuter cover)＝1.47，EInner part/EOuter coverWhen the value is 47, the bounce effect is best. The silica gel for manufacturing the hemispherical caps is modeled by using an incompressible material model, and in the process of changing the superelasticity parameter, an outer ball with the elastic modulus of 74KPa and an inner ball with the elastic modulus of 3.48MPa are simulated by using a Mooney-Rivlin model respectively, wherein the outer ball parameter D1 is 0.05, the D2 is 0.005, the inner ball parameter D1 is 0.4947, and the D2 is 0.0639, so that the best bouncing effect can be obtained. In the axisymmetric finite element simulation of the driver, axisymmetric models were created to respectively simulate the outer sphere and the inner sphere, and were discretized using an unstructured grid of 4-node bilinear axisymmetric fixed elements (ABAQUS element type: CAX4H), the grid size being adjusted to 2 mm. To eliminate the translation and rotation of the rigid body, the nodal points on the contact line of the boundary impose the boundary condition of end-fixed Uy.
The outer hemisphere 41 is made of a silicone material having an elastic modulus of 74KPa, and the inner hemisphere 42 is made of a silicone material having an elastic modulus of 3.48 MPa. In other embodiments, the outer hemisphere may be made of a material having an elastic modulus of 50.9 to 91.4KPa, and the inner hemisphere may be made of a material having an elastic modulus of 2.7 to 4.3 MPa. The pneumatic bounce driver made of the material with the specification can balance the bounce height of the double-motion-mode robot and the adverse effect on the peristalsis of the double-motion-mode robot. Silicone material can be used for both the outer hemisphere and the inner hemisphere. In this embodiment, the flange a and the flange B are hermetically connected by using a silicone material with an elastic modulus of 74 KPa.
In this embodiment, the pneumatic bending actuator 3 includes a pneumatic mesh soft actuator 31 and a restoring member (not shown), and the restoring member is a tension spring. Referring to fig. 2, there are two pneumatic grid soft actuators 31, two ends of each pneumatic grid soft actuator 31 are respectively fixedly connected to the front trunk portion 11 and the rear trunk portion 12, tension springs are disposed in the reset member installation groove a111 and the reset member installation groove B112 and are disposed above the rotation shaft 13, one end of each tension spring is connected to the front trunk portion 11 in a hook-and-pull manner, and the other end of each tension spring is connected to the rear trunk portion 12 in a hook-and-pull manner. The pneumatic grid soft driver has good deformation promoting effect, but when the pneumatic grid soft driver is in a straight state, the straightening effect on the bendable trunk is weak, and the resetting piece can improve the resetting speed of the bendable trunk. Because the bendable trunk has a width, in this embodiment, two pneumatic mesh soft drivers 31 are provided, the two pneumatic mesh soft drivers 31 are symmetrically distributed on two sides of the bendable trunk with the reset piece as a center line, and the two pneumatic mesh soft drivers and the reset piece are symmetrically distributed on the bendable trunk with the rotating shaft 13 as a center line.
Since the pneumatic grid soft driver is used for rotating the front body part relative to the rear body part in a counterclockwise direction, in other embodiments, the reset element may also be a compression spring, one end of the compression spring is fixedly connected with the front body part 11, the other end of the compression spring is fixedly connected with the rear body part 12, and the compression spring is arranged below the rotating shaft 13.
In this embodiment, the bendable trunk 1 further includes a reverse bending limiting part (not shown), the reverse bending limiting part is fixedly connected to the front trunk 11 and extends above the rear trunk 12, and when the included angle between the front trunk 11 and the rear trunk 12 is 180 degrees, the reverse bending limiting part abuts against the rear trunk, so that even if the pneumatic grid soft driver is in an uninflated state, the reset piece cannot pull the rear trunk 12 to bend reversely relative to the front trunk 11, which saves more energy than limiting the reverse bending of the front trunk relative to the rear trunk through the pneumatic bending driver.
In other embodiments, the angle of the anti-flexion limiting portion to the anti-flexion between the front torso portion 11 and the rear torso portion 12 may be set as desired. In other embodiments, a recurve bank may be fixedly attached to rear torso member 12 to limit the reverse flexion of front torso member 11 relative to rear torso member 12. The reverse bending of the front torso part relative to the rear torso part is restricted by the reverse bending restricting part.
When the pneumatic bounce driver is simultaneously hard-connected with the two ends of the bendable trunk, the pneumatic bounce driver has to select a soft structure, because: the pneumatic bounce driving part is arranged below the bendable trunk, the bendable trunk is driven to bend by the pneumatic bounce driver without being affected, if the rigid body structure is selected by the pneumatic bounce driving part, the connection mode of the pneumatic bounce driving part and the bendable trunk or the front and back feet must use flexible connection, but when the flexible trunk is driven by the pneumatic bounce driving part to bounce, the flexible connection cannot enable the acting force of the pneumatic bounce driving part to be transmitted to the bendable trunk, and the bounce function cannot be realized. Therefore, when the pneumatic bounce driving part selects a soft body structure, the connection mode of the pneumatic bounce driving part and the bendable trunk or the front and back feet can adopt hard connection, so that when the pneumatic bounce driving part drives the bendable trunk to bounce, the hard connection can enable the acting force of the pneumatic bounce driving part to be transmitted to the bendable trunk, and the bounce function can be realized. When the pneumatic bending driver drives the bendable trunk to bend, the hard connection enables the acting force to be conducted to the pneumatic bounce driving part, and the pneumatic telescopic soft driver can deform again, so that the bending of the bendable trunk is not affected, and the peristalsis function is realized.
The invention is described in detail above with reference to the figures and examples. It should be understood that in practice the description of all possible embodiments is not exhaustive and that the inventive concepts are described herein as far as possible by way of illustration. Without departing from the inventive concept of the present invention and without any creative work, a person skilled in the art should, in all of the embodiments, make optional combinations of technical features and experimental changes of specific parameters, or make a routine replacement of the disclosed technical means by using the prior art in the technical field to form specific embodiments, which belong to the content implicitly disclosed by the present invention.
Claims (10)
1. A robot with double motion modes comprises a bendable trunk and is characterized by further comprising a pneumatic bending driver and a pneumatic bouncing driver; the front end of the bendable trunk is fixedly connected with a front foot, the rear end of the bendable trunk is fixedly connected with a rear foot, and the landing positions of the front foot and the rear foot determine a reference plane; two ends of the pneumatic bending driver are respectively fixedly connected with two ends of the bendable trunk; the pneumatic bounce drive is rigidly connected to the bendable torso with its lowest point movable from above the datum level to below the datum level.
2. The dual-motion mode robot of claim 1, further comprising an air control assembly mounted on the bendable trunk, wherein the pneumatic bending driver is provided with a bending driver air port, the pneumatic bouncing driver is provided with a bouncing driver air port, the air control assembly comprises an air pump, a control processor, a bending control electromagnetic directional valve and a bouncing control electromagnetic directional valve, the bending control electromagnetic directional valve is communicated with the bending driver air port pipeline, the bouncing control electromagnetic directional valve is communicated with the bouncing driver air port pipeline, and an output end of the control processor is respectively electrically connected with a control end of the bending control electromagnetic directional valve and a control end of the bouncing control electromagnetic directional valve.
3. The dual-motion modal robot of claim 2, wherein the pneumatic control assembly comprises a solar panel for powering the air pump, the control processor, the bend control solenoid directional valve, and the bounce control solenoid directional valve.
4. The dual-motion mode robot of claim 1, wherein the pneumatic bounce driver comprises an outer hemisphere and an inner hemisphere, the edge of the outer hemisphere is sealingly connected to the edge of the inner hemisphere, a bounce driver air port is provided in the outer hemisphere, the outer hemisphere and the inner hemisphere are both made of an elastic material, and the elastic modulus of the outer hemisphere is smaller than that of the inner hemisphere, and the outer hemisphere is respectively rigidly connected to the two ends of the bendable trunk.
5. A dual-motion modal robot as claimed in claim 4, wherein the inner radius of the outer hemisphere is given by ROuter coverWith a thickness tOuter coverThe elastic modulus of the material is EOuter cover(ii) a The inner radius of the inner hemisphere is RInner partWith a thickness tInner partThe elastic modulus of the material is EInner part；
6. The robot of claim 1 wherein said pneumatic bounce drive has an upward bounce line disposed on a travel surface defined by said forefoot and said rearfoot, said upward bounce line having an angle of greater than or equal to 45 ° and less than 90 ° with said reference surface, and said upward bounce line being disposed forward of a normal to said reference surface.
7. A dual-motion modal robot as recited in claim 1, wherein the bendable torso comprises a front torso member and a rear torso member, the front and rear torso members being rotatably coupled, the pneumatic bounce drive being hard-wired to the front torso member or the pneumatic bounce drive being hard-wired to the rear torso member.
8. The dual motion modality robot of claim 7 wherein the forefoot and hindfoot each comprise a leg and a toe, the toe being disposed rearwardly and downwardly of the leg and being at an obtuse included angle with the leg.
9. The dual-motion mode robot of claim 1, wherein the pneumatic bending actuator comprises a pneumatic mesh soft actuator and a reset element, two ends of the pneumatic mesh soft actuator are respectively and fixedly connected with two ends of the bendable trunk, and two ends of the reset element are respectively connected with two ends of the bendable trunk.
10. A dual-motion modal robot according to claim 1, wherein the bendable torso comprises a front torso member, a rear torso member, and a recurve limiting portion, the front torso member and the rear torso member being rotatably coupled, the axes of rotation of the front torso member and the rear torso member being disposed parallel to the reference plane, the recurve limiting portion being fixedly coupled to the front torso member for limiting the backward bending of the rear torso member relative to the front torso member, or the recurve limiting portion being fixedly coupled to the rear torso member for limiting the backward bending of the front torso member relative to the rear torso member.
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