Leg structure with gravity compensation

Abstract

The utility model provides a leg structure with gravity compensation, which comprises a first leg, a second leg, a driving assembly and a gravity compensation module, the driving assembly comprises a driving part mounted at one end of the first leg, and the driving part is used for driving the second leg to rotate, so that the first leg and the second leg are relatively opened and closed; the gravity compensation module comprises a limiting part, a guide column and a reset part, the limiting part is connected to the end, close to the driving part, of the first leg part, a limiting cover is arranged at one end of the guide column, the other end of the guide column penetrates through the limiting part and is rotationally connected to the second leg part through a rotating structure, and the reset part is arranged in the circumferential direction of the guide column; the reset piece abuts against the position between the limiting piece and the limiting cover. According to the leg structure provided by the invention, the extra acting degree of the driving part can be reduced, so that the driving part can be prevented from being overheated or damaged, energy consumption can be reduced, endurance can be prolonged, the service life can be prolonged, and the requirement for model selection of the driving part can be reduced.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of robot leg structure arrangement, and in particular to a leg structure with gravity compensation. BACKGROUND

[0002] When a wheel-legged robot works on a complex unstructured terrain, the gravity of the mechanical structure itself during work often acts as a resistance, which requires the driving element of the mechanism to do additional work to offset it, thereby increasing the requirements for the driving element, which may be overheated or damaged. CONTENT

[0003] In order to overcome the shortcomings of the prior art, the purpose of the present application is to provide a leg structure with gravity compensation, so as to reduce the degree of additional work of the driving element, thereby preventing the driving element from overheating or being damaged. Therefore, the leg structure with gravity compensation provided by the present application is beneficial to reduce energy consumption, thereby increasing the endurance, improving the service life, and reducing the requirements for the selection of the driving element.

[0004] To solve the above problems, the technical scheme adopted by the present application is as follows:

[0005] A leg structure with gravity compensation, comprising a first leg, a second leg and a driving assembly, the driving assembly comprising a driving element, the driving element being installed at one end of the first leg, the driving element being used to drive the second leg to rotate, so that the first leg and the second leg are relatively opened and closed, further comprising:

[0006] A gravity compensation module, the gravity compensation module comprising:

[0007] A limiting piece connected to one end of the first leg close to the driving element, the limiting piece being placed outside the opening and closing angle formed between the first leg and the second leg;

[0008] A guide column, one end of the guide column being provided with a limiting cover, the other end of the guide column penetrating through the limiting piece and being rotatably connected to the second leg through a rotating structure, the guide column being slidably connected to the limiting piece; and

[0009] A reset piece, the reset piece being arranged in the circumferential direction of the guide column, one end of the reset piece abutting against the limiting piece, the other end of the reset piece abutting against the limiting cover.

[0010] In some possible implementation manners, the rotating structure is a fisheye bearing or a universal ball head bearing, and the end surface of the second leg away from the first leg is convexly provided with a connecting shaft relative to the opening and closing angle, the connecting shaft penetrating through the rotating structure, so that the rotating structure can rotate around the connecting shaft.

[0011] In some possible embodiments, the guide column is detachably connected to the rotating structure, and the limiting member comprises:

[0012] a fixing seat connected to the first leg;

[0013] a limiting sleeve disposed through the fixing seat, the guide column being disposed through the limiting sleeve, the reset member abutting against an end surface of the limiting sleeve opposite to the limiting cover, and an outer surface of the limiting sleeve being provided with two limiting grooves which are arc grooves or annular grooves, and the fixing seat being disposed between the two limiting grooves; and

[0014] two arc-shaped stop rings, an inner arc surface of each of the arc-shaped stop rings being disposed opposite to a bottom wall of one of the limiting grooves, a portion of the arc-shaped stop ring being disposed in the limiting groove, and another portion of the arc-shaped stop ring abutting against an end surface of the fixing seat.

[0015] In some possible embodiments, the first leg comprises:

[0016] two first rods disposed at intervals, the driving member being mounted to the two first rods, one of the first rods exposing an output shaft of the driving member, and the limiting member being connected to the first rod exposing the output shaft; and

[0017] a plurality of first connecting columns disposed at intervals, each of the first connecting columns being connected between two of the first rods.

[0018] The second leg comprises:

[0019] two second rods disposed at intervals, one end of one of the second rods protruding from the other second rod to be connected to the output shaft, and the guide column being rotatably connected to the second rod connected to the driving member; and

[0020] a plurality of second connecting columns disposed at intervals, each of the second connecting columns being connected between two of the second rods.

[0021] In some possible embodiments, each of the first rods is provided with a first insertion hole, and the first leg further comprises:

[0022] a first support plate comprising a first support portion and a first connecting portion, the first support portion abutting between two of the first rods, the first support portion being provided with the first connecting portion opposite to each end of the first rod, each of the first connecting portions being fixed in the first insertion hole, and a projection of the first connecting portion being disposed in the first support portion.

[0023] Each of the second rods is provided with a second insertion hole, and the second leg further comprises:

[0024] A second support plate comprises a second support part and a second connecting part, the second support part is in abutment between two second rod members, the second support part is provided with the second connecting part relative to each end of the second rod member, the second connecting part is fixed in the second socket, and the projection of the second connecting part is placed in the second support part.

[0025] In some possible implementation manners, the driving assembly further comprises:

[0026] A flange isolation member is connected between the output shaft of the driving member and the protruding second rod member.

[0027] In some possible implementation manners, the driving assembly further comprises:

[0028] A bearing member is sleeved on the circumferential surface of the flange isolation member, and the bearing member is in abutment between the adjacent first rod member and the second rod member.

[0029] In some possible implementation manners, the rotating structure is screwed on the guide column.

[0030] In some possible implementation manners, the limiting sleeve is a linear bearing.

[0031] In some possible implementation manners, the first rod member connected with the limiting member comprises a first main body and a first boss connected with each other, the first connecting column is arranged on the first main body, the driving member is arranged on the first main body, and the limiting member is arranged on the first boss.

[0032] The protruding second rod member comprises a second main body and a second boss connected with each other, the second connecting column is arranged on the second main body, the second main body is connected with the output shaft, and the guide column is rotatably connected with the second boss.

[0033] Compared with the prior art, the utility model has the beneficial effects that:

[0034] In the present application, an additional gravity compensation module is provided, which includes a limit member, a guide column and a reset member. The limit member is connected to one end of the first leg close to the driving member, and the other end of the guide column is provided with a limit cover. The other end of the guide column passes through the limit member to be rotatably connected to the second leg. The reset member is arranged circumferentially around the guide column, and one end of the reset member abuts the limit member, and the other end of the reset member abuts the limit cover, so that when the first leg and the second leg are relatively opened and closed, the reset member can deform to provide elastic force. The elastic force provided by the reset member can at least partially offset the gravitational torque generated by gravity on the output shaft of the driving member, thereby reducing the degree of additional work done by the driving member, and thus helping to prevent the driving member from overheating or damage. Therefore, the leg structure with gravity compensation provided in the present application is conducive to reducing energy consumption to increase battery life, improve service life and reduce requirements for driving member selection. BRIEF DESCRIPTION OF THE DRAWINGS

[0035] Figure 1 A schematic structural diagram of a leg structure with gravity compensation provided in one embodiment of the present application;

[0036] Figure 2 for Figure 1 An exploded view of a partial structure of the leg structure is shown;

[0037] Figure 3 This is a simplified diagram of the gravity compensation principle;

[0038] Figure 4 for Figure 1 The structural diagram of the gravity compensation module is shown.

[0039] Description of reference numerals:

[0040] 100 - leg structure; 10 - first leg; 11 - first rod; 111 - first body; 112 - first boss; 110 - first insertion hole; 12 - first connecting column; 13 - first support plate; 131 - first support portion; 132 - first connecting portion; 20 - second leg; 21 - second rod; 211 - second body; 212 - second boss; 210 - second insertion hole; 22 - second connecting column; 23 - second support plate; 231 - second support portion; 232 - second connecting portion; 30 - drive assembly; 31 - drive member; 32 - flange isolation member; 33 - bearing member; 40 - gravity compensation module; 41 - limit member; 411 - fixing seat; 412 - limit sleeve; 413 - arc-shaped retaining ring; 42 - guide column; 43 - limit cover; 44 - rotating structure; 45 - reset member. DETAILED DESCRIPTION

[0041] With reference to the drawings of the embodiments of the present application, the technical solutions in the embodiments of the present application will be clearly and completely described. Obviously, the described embodiments are only a part of the embodiments of the present application, rather than all the embodiments of the present application. Based on the embodiments of the present application, all the other embodiments obtained by those of ordinary skill in the art without creative effort should fall within the scope of the present application.

[0042] The terms "first", "second", etc. in the specification and claims of the present application and the above drawings are used to distinguish different objects, rather than to describe a specific sequence. In addition, the terms "include" and "have" and any variations thereof are intended to cover non-exclusive inclusion. It should be noted that when an element is referred to as "fixed to" another element, it can be directly on the other element or there can be a middle element. When an element is referred to as "connected to" another element, it can be directly connected to the other element or there can be a middle element. When an element is referred to as "provided on" another element, it can be provided on the other element or there can be a middle element.

[0043] Reference Figure 1 An embodiment of the present application provides a leg structure with gravity compensation, hereinafter referred to as leg structure 100, which comprises a first leg 10, a second leg 20, a driving assembly 30 and a gravity compensation module 40. In combination with reference to Figure 2 The driving assembly 30 comprises a driving member 31, which is installed at one end of the first leg 10. The driving member 31 is used to drive the second leg 20 to rotate, so that the first leg 10 and the second leg 20 are relatively opened and closed. Exemplarily, the driving member 31 can be a servo motor.

[0044] The gravity compensation module 40 comprises a limiting member 41, a guide column 42 and a reset member 45. The limiting member 41 is connected to one end of the first leg 10 close to the driving member 31, and is placed outside the opening and closing angle formed between the first leg 10 and the second leg 20. One end of the guide column 42 is provided with a limiting cover 43, and the other end of the guide column 42 passes through the limiting member 41 and is rotatably connected to the second leg 20 through a rotating structure 44. The guide column 42 is slidably connected to the limiting member 41. The reset member 45 is arranged in the circumferential direction of the guide column 42, one end of the reset member 45 abuts against the limiting member 41, and the other end of the reset member 45 abuts against the limiting cover 43. Thus, when the first leg 10 and the second leg 20 are relatively opened and closed, the guide column 42 can be moved, so as to promote the reset member 45 to be deformed in extension and contraction between the limiting cover 43 and the limiting member 41, thereby providing elastic force. Exemplarily, the reset member 45 can be a spring or an elastic sleeve.

[0045] The mechanism diagram of the gravity compensation principle is as shown in Figure 3As shown, m, L, θ in the diagram represent the mass of the center of mass, the length of the connecting rod and the joint angle respectively. Under the action of gravity at the center of mass M, a gravity torque will be generated on the motor rotating shaft O, and the size is:

[0046] τ = mgL sin θ

[0047] The gravity torque at point A is equivalent to f g , h1 is the distance from the fixed point of the reset member to the rotating shaft O point, and the following has:

[0048]

[0049] When the mechanism is in a balanced state, f g and the elastic force f follow the force quadrilateral rule The resultant force f z will pass through the rotating shaft point O, at which time the gravity torque of the rotating shaft O is zero. When the extension amount of the reset member 45 is x, combined with statics analysis, it is easy to get f, f z , f g The force triangle formed by f, f and f is similar to triangle AOB, so:

[0050]

[0051] Substitute the reset member 45 tension f = kx (k is the stiffness coefficient of the reset member) into the elimination of f:

[0052]

[0053] Finally, the simplified formula has all the values represented by the symbols in the formula as constants, which are independent of θ. That is, when the k value of the reset member 45 satisfies the above formula, the mechanism will be in a static equilibrium state, and no matter what the value of θ is, the tension torque generated by the reset member 45 on the O point can just offset the gravity torque generated by the gravity on the O point, that is, perfect balance is achieved. When the k value of the reset member 45 is selected as other values, at least part of the gravity torque generated by the gravity on the O point can be offset, so as to reduce the degree of additional work of the driving member 31, and further to prevent the driving member 31 from overheating or damage.

[0054] In the present application, the gravity compensation module 40 is additionally provided, the gravity compensation module 40 comprises a limiting piece 41, a guide column 42 and a reset piece 45, the limiting piece 41 is connected to one end of the first leg portion 10 close to the driving piece 31, the other end of the guide column 42 is provided with a limiting cover 43, the other end of the guide column 42 passes through the limiting piece 41 to be rotatably connected with the second leg portion 20, the reset piece 45 is arranged around the circumference of the guide column 42, one end of the reset piece 45 abuts against the limiting piece 41, the other end of the reset piece 45 abuts against the limiting cover 43, so that when the first leg portion 10 and the second leg portion 20 relatively open and close, the reset piece 45 can be deformed to provide a elastic force, the elastic force provided by the reset piece 45 can at least partially offset the gravity torque generated by the gravity at the output shaft of the driving piece 31, so as to reduce the degree of additional work of the driving piece 31, thereby facilitating to prevent the driving piece 31 from overheating or being damaged, therefore, the leg portion structure with gravity compensation provided by the present application is beneficial to reduce energy consumption, thereby facilitating to increase the endurance, facilitating to improve the service life and facilitating to reduce the requirement for the selection of the driving piece 31.

[0055] In some embodiments, the rotating structure 44 is a fisheye bearing or a universal ball head bearing, and the end surface of the second leg portion 20 away from the first leg portion 10 is convexly provided with a connecting shaft, and the second leg portion 20 is provided with a mounting hole, so that one end of the connecting shaft is fixed in the mounting hole to realize installation, the connecting shaft passes through the rotating structure 44, so that the rotating structure 44 can rotate around the rotating shaft, thereby realizing the rotatable connection of the guide column 42 and the second leg portion 20. The fisheye bearing or the universal ball head bearing is selected for the rotating structure 44, which is beneficial to increase the activity range of the gravity compensation module 40 and improve the adaptability of the structure.

[0056] In some embodiments, referring to Figure 1 and Figure 4The guide column 42 is detachably connected to the rotating structure 44. The limiting piece 41 comprises a fixing base 411, a limiting sleeve 412 and two arc-shaped stop washers 413. The fixing base 411 is connected to the first leg portion 10. For example, the fixing base 411 is detachably connected to the first leg portion 10. Specifically, the fixing base 411 can be inserted into the first leg portion 10 and fixed by a gasket. It can be understood that the fixing base 411 can also be fixed to the first leg portion 10 by direct buckling. The limiting sleeve 412 is arranged through the fixing base 411. The guide column 42 is arranged through the limiting sleeve 412. The reset piece 45 abuts against one end surface of the limiting sleeve 412 opposite the limiting cover 43. In view of the limiting cover 43, an outer surface of the limiting sleeve 412 is provided with two limiting grooves which are arc-shaped grooves or annular grooves (in this embodiment, the limiting grooves are annular grooves). The fixing base 411 is arranged between the two limiting grooves. An inner arc surface of each arc-shaped stop washer 413 is arranged opposite a bottom wall of one limiting groove. A part of the arc-shaped stop washer 413 is arranged in the limiting groove. Another part of the arc-shaped stop washer 413 abuts against one end surface of the fixing base 411. The structure of the limiting piece 41 cooperates with the detachable connection of the guide column 42, which is beneficial to improve the disassembly and assembly convenience of the gravity compensation module 40.

[0057] In some embodiments, the limiting sleeve 412 is a linear bearing, which is beneficial to reduce sliding resistance.

[0058] In another embodiment, the limiting sleeve 412 can be a graphite copper sleeve or a limiting sleeve made of other materials.

[0059] In some embodiments, the rotating structure 44 is screwed to the guide column 42. On the one hand, this is beneficial to ensure the connection strength. On the other hand, this is beneficial to improve the disassembly and assembly simplicity. For example, an external thread structure can be arranged on the surface of the rotating structure 44. An internal thread structure can be arranged in the guide column 42, so that the rotating structure 44 is screwed to the guide column 42.

[0060] In another embodiment, the rotating structure 44 and the guide column 42 can be detachably connected by plug buckling.

[0061] In some embodiments, with reference to Figure 1 and Figure 2The first leg 10 comprises two first rods 11 and a plurality of first connecting columns 12. The driving member 31 is installed on the two first rods 11. One of the first rods 11 is exposed to the output shaft of the driving member 31. The limiting member 41 is connected to the first rod 11 exposed to the output shaft. Each of the first connecting columns 12 is connected between the two first rods 11. The second leg 20 comprises two second rods 21 and a plurality of second connecting columns 22. One end of one of the second rods 21 is protruded from the other second rod 21 to be connected to the output shaft. The guide column 42 is rotatably connected to the second rod 21 connected to the driving member 31. Each of the second connecting columns 22 is connected between the two second rods 21. The rods of the first leg 10 and the second leg 20 are connected by the connecting columns, which is beneficial to reduce the adverse effects of linear displacement perpendicular to the central axis of the rods, thereby improving the service life of the legs. In addition, the protruded arrangement of one of the second rods 21 is beneficial to reduce the space interference between the first leg 10 and the second leg 20, thereby expanding the range of movement between the first leg 10 and the second leg 20.

[0062] For example, the first rods 11 and the second rods 21 can be 5052 aluminum alloy rods with a thickness of 4mm or 6mm. For example, the first connecting columns 12 and the second connecting columns 22 can be M4 aluminum columns. For example, the first connecting columns 12 and the second connecting columns 22 can be connected by being inserted into the fixing holes.

[0063] In some embodiments, with reference to Figure 2Each first rod member 11 is provided with a first insertion hole 110. The first leg 10 further comprises a first support plate 13, which comprises a first support portion 131 and a first connecting portion 132. The first support portion 131 is arranged between two first rod members 11. For example, the first support portion 131 can be arranged perpendicularly to the first rod members 11. The first support portion 131 is provided with a first connecting portion 132 at each end thereof. For example, each end of the first support portion 131 can be provided with one or at least two first connecting portions 132. Each first connecting portion 132 is fixed in a first insertion hole 110. The projection of the first connecting portion 132 is arranged in the first support portion 131. Each second rod member 21 is provided with a second insertion hole 210. The second leg 20 further comprises a second support plate 23, which comprises a second support portion 231 and a second connecting portion 232. The second support portion 231 is arranged between two second rod members 21. For example, the second support portion 231 can be arranged perpendicularly to the second rod members 21. The second support portion 231 is provided with a second connecting portion 232 at each end thereof. For example, each end of the second support portion 231 can be provided with one or at least two second connecting portions 232. Each second connecting portion 232 is fixed in a second insertion hole 210. The projection of the second connecting portion 232 is arranged in the second support portion 231. The support plate is connected between two rod members by means of a mortise and tenon joint. This is conducive to improving the rigidity of the rod members in the cross-sectional direction and the normal direction, while avoiding the increase in mass caused by the use of screws for fixation, thereby also being conducive to reducing the energy consumption of the driving member 31. For example, the support plate can be a 5052 aluminum alloy plate.

[0064] In some embodiments, the driving assembly 30 further comprises a flange isolation member 32, which is connected between the output shaft of the driving member 31 and the protruding second rod member 21. The flange isolation member 32 is conducive to improving the compactness of the connection between the driving member 31 and the corresponding rod member. For example, the flange isolation member 32 can be fixed to the driving member 31 and the second rod member 21 by means of screws.

[0065] In some embodiments, the driving assembly 30 further comprises a bearing member 33, which is sleeved on the circumferential surface of the flange isolation member 32. The bearing member 33 is arranged between the adjacent first rod member 11 and the second rod member 21. For example, the bearing member 33 can be a thin deep groove ball bearing with a model number of 6807ZZ. The bearing member 33 can bear loads from the radial and axial directions.

[0066] In some embodiments, with reference to Figure 1 and Figure 2The first rod member 11 connected to the limiting member 41 comprises a first body 111 and a first boss 112 connected to each other. The first body 111 and the first boss 112 can be integrally formed. The first connecting column 12 is arranged on the first body 111. The driving member 31 is arranged on the first body 111. The limiting member 41 is arranged on the first boss 112. The second rod member 21 protrudes and comprises a second body 211 and a second boss 212 connected to each other. The second body 211 and the second boss 212 can be integrally formed. The second connecting column 22 is arranged on the second body 211. The second body 211 is connected to the output shaft. The guide column 42 is rotatably connected to the second boss 212. The structure of the first rod member 11 and the second rod member 21 can reduce the mass of the leg structure.

[0067] The above-mentioned embodiments are only preferred embodiments of the present application, and cannot be used to limit the scope of protection of the present application. Any non-essential changes and replacements made by those skilled in the art based on the present application shall fall within the scope of protection of the present application.

Claims

1. A leg structure with gravity compensation, comprising a first leg, a second leg, and a drive assembly, the drive assembly comprising a drive member mounted to one end of the first leg, the drive member for driving the second leg to rotate such that the first leg and the second leg open and close relative to each other, characterized in that, Also included are: a gravity compensation module, the gravity compensation module comprising: a limiting piece connected to the first leg near one end of the driving piece, the limiting piece being placed outside the opening and closing angle formed between the first leg and the second leg; a guide column, one end of the guide column being provided with a limiting cap, the other end of the guide column passing through the limiting piece and being rotatably connected to the second leg through a rotating structure, the guide column being slidably connected to the limiting piece; and a reset piece arranged circumferentially around the guide column, one end of the reset piece abutting against the limiting piece, the other end of the reset piece abutting against the limiting cap.

2. The leg structure of claim 1, wherein, The rotating structure is a fisheye bearing or a universal ball head bearing, and the end face of the second leg away from the first leg is convexly provided with a connecting shaft relative to the opening and closing angle, the connecting shaft passing through the rotating structure, so that the rotating structure can rotate around the connecting shaft.

3. The leg structure of claim 2, wherein, The guide column is detachably connected to the rotating structure, the limiting piece comprises: a fixed seat connected to the first leg; a limiting sleeve provided through the fixed seat, the guide column being provided through the limiting sleeve, the reset piece abutting against one end face of the limiting sleeve relative to the limiting cap, the outer surface of the limiting sleeve being provided with two limiting grooves relative to the limiting cap, the limiting grooves being arc-shaped grooves or annular grooves, the fixed seat being arranged between the two limiting grooves; and two arc-shaped retaining rings, the inner arc face of each arc-shaped retaining ring being arranged relative to the bottom wall of one limiting groove, a part of the arc-shaped retaining ring being arranged in the limiting groove, the other part of the arc-shaped retaining ring abutting against one end face of the fixed seat.

4. The leg structure of claim 1, wherein, The first leg comprises: two first rods arranged at intervals, the driving piece being mounted on the two first rods, one first rod exposing the output shaft of the driving piece, the limiting piece being connected to the first rod exposing the output shaft; and a plurality of first connecting columns arranged at intervals, each first connecting column being connected between two first rods; The second leg comprises: two second rods arranged at intervals, one end of one second rod protruding from the other second rod to be connected to the output shaft, the guide column being rotatably connected to the second rod connected to the driving piece; and a plurality of second connecting columns arranged at intervals, each second connecting column being connected between two second rods.

5. The leg structure of claim 4, wherein Each first rod is provided with a first insertion hole, the first leg further comprising: a first support plate, the first support plate comprising a first support portion and a first connecting portion, the first support portion abutting between two first rods, the first support portion being provided with the first connecting portion relative to each end of the first rod, each first connecting portion being fixed in the first insertion hole, the projection of the first connecting portion being arranged in the first support portion; Each second rod is provided with a second insertion hole, the second leg further comprising: A second support plate comprises a second support part and a second connecting part, the second support part is in abutment between two second rod members, the second support part is provided with the second connecting part relative to each end of the second rod member, the second connecting part is fixed in the second socket, and a projection of the second connecting part is placed in the second support part.

6. The leg structure of claim 4, wherein, The driving assembly further comprises: A flange isolation member is connected between the output shaft of the driving member and a protruding second rod member.

7. The leg structure of claim 6, wherein The driving assembly further comprises: A bearing member is sleeved on the circumferential surface of the flange isolation member, and the bearing member is in abutment between the adjacent first rod member and the second rod member.

8. The leg structure of claim 3, wherein, The rotating structure is screwed to the guide column.

9. The leg structure of claim 3, wherein, The limiting sleeve is a linear bearing.

10. The leg structure of claim 4, wherein, The first rod member connected to the limiting member comprises a first main body and a first boss connected to each other, the first connecting column is installed on at least the first main body, the driving member is installed on the first main body, and the limiting member is installed on the first boss. The protruding second rod member comprises a second main body and a second boss connected to each other, the second connecting column is installed on the second main body, the second main body is connected to the output shaft, and the guide column is rotatably connected to the second boss.

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