CN112722112A

CN112722112A - Mechanical bionic foot and bionic walking robot

Info

Publication number: CN112722112A
Application number: CN202110184285.9A
Authority: CN
Inventors: 戴松林; 王林欢; 王臻
Original assignee: Zhejiang Hailun Horticulture Co ltd
Current assignee: Zhejiang Hailun Horticulture Co ltd
Priority date: 2021-02-02
Filing date: 2021-02-08
Publication date: 2021-04-30
Anticipated expiration: 2041-02-08
Also published as: CN112722112B

Abstract

The invention discloses a mechanical bionic foot and a bionic walking robot, wherein the mechanical bionic foot comprises a bracket; a limb rotatable about a first pivot axis provided on the support; the driving mechanism is arranged on the bracket, and the power output end of the driving mechanism can form a motion track with two degrees of freedom when the driving mechanism is driven by a driving device, and the power output end is coupled to the limb; wherein, the limbs are provided with walking ends, and the limbs are arranged to amplify the motion trail of the power output end on the walking ends in equal proportion. Therefore, the motion trail of the power output end can be reflected on the walking end of the limb after being amplified in equal proportion through the limb, and the motion trail of the walking end is stable and controllable; and the walking can be realized only by driving the driving mechanism through one driving device, so that the light weight of the mechanical bionic foot is realized, and the production cost of the mechanical bionic foot is reduced.

Description

Mechanical bionic foot and bionic walking robot

Technical Field

The invention relates to a walking mechanism, in particular to a mechanical bionic foot and a bionic walking robot.

Background

The walking mechanism is a walking mechanism mainly used on uneven road surfaces because the walking mechanism can adapt to complex road surfaces and has wide adaptability. The commonly used walking mechanism has two feet, four feet, six feet, eight feet and other forms, each foot has at least two degrees of freedom in order to enable each foot of the walking mechanism to have a walking function, in general, each degree of freedom needs to be driven by a motor independently, and each motor needs to realize the coordinated movement of the two degrees of freedom of the foot by means of the operation program control of a computer, so the realization method is complex, and the weight and the cost of each foot are increased. In order to solve the problem, some schemes try to adopt a single motor for driving, but because the motions of two degrees of freedom cannot be well coordinated, the uneven phenomenon of 'the gravity center of the frame is suddenly turned up and down and the height is fluctuated' occurs during walking, so that the running load of feet is increased; some proposals attempt to use a single motor to drive, but the structural configuration of the foot is very different from the native configuration of an animal's true leg, and the walking stride of the foot is shortened, limiting the range of motion of the foot.

Disclosure of Invention

One of the objects of the present invention is to provide a mechanical bionic foot to solve at least one of the above technical problems.

The mechanical bionic foot comprises a bracket; a limb rotatable about a first pivot axis provided on the support; the driving mechanism is arranged on the bracket, and the power output end of the driving mechanism can form a motion track with two degrees of freedom when the driving mechanism is driven by a driving device, and the power output end is coupled to the limb; wherein, the limbs are provided with walking ends, and the limbs are arranged to amplify the motion trail of the power output end on the walking ends in equal proportion.

Therefore, when the driving mechanism moves, the motion trail of the power output end can be amplified in equal proportion through the limbs, and the amplified motion trail of the power output end is reflected on the walking end of the limbs, so that the motion trail of the walking end is stable and controllable; the driving mechanism can obtain a walking track reflecting two degrees of freedom only by driving the driving mechanism by one driving device, namely, the power output end can translate in at least 2 orthogonal directions, so that the walking function of the mechanical bionic foot is realized, and the walking control of the mechanical bionic foot is simplified; and a plurality of driving devices are not required to be arranged, so that the light weight of the mechanical bionic foot is realized, and the production cost is reduced. When a plurality of mechanical bionic feet are needed, the supports of all the mechanical bionic feet are connected to form a whole.

In some embodiments, the limb comprises a parallelogram mechanism which can rotate around a first pivot shaft arranged on the bracket, the parallelogram mechanism is a deformable parallelogram formed by a first edge, a second edge, a third edge and a fourth edge which are sequentially connected end to end through a second pivot shaft in a pivoting way, the third edge is arranged on the first pivot shaft, and the first pivot shaft and the second pivot shaft are arranged in parallel; and a walking end arranged on the first side, namely the limb is obtained by adding or expanding a parallelogram mechanism; the power output end is pivotally connected to the parallelogram mechanism through a third pivot shaft parallel to the first pivot shaft, and the position of the third pivot shaft is arranged on a connecting line of the first pivot shaft and the walking end; the positions of the first pivot shaft, the third pivot shaft and the walking end are set to be that in a virtual walking parallelogram taking a connecting line of the first pivot shaft and the walking end as a diagonal line, at least one second pivot shaft on the first edge and at least one second pivot shaft on the third edge are respectively distributed on two pairs of edges, and the other two pairs of edges are parallel to the second edges. The walking end and the first pivot shaft are respectively arranged on two opposite sides of the parallelogram mechanism and are respectively positioned on two sides of the parallelogram mechanism which are deviated from each other, generally, the walking end and the first pivot shaft are arranged on the outer side of the parallelogram mechanism, and the amplification ratio of the obtained limb is larger; in the extreme case, the first pivot axis is arranged on the second pivot axis of the third side closest thereto, where the resulting magnification of the limb is smaller. In a preferred embodiment, the line connecting the walking end with the further distant second pivot axis on the first side is collinear with the line connecting the two second pivot axes on the first side.

When the driving mechanism moves, the parallelogram mechanism deforms while rotating around the first pivot shaft under the driving of the power output end, and the connecting line of the power output end and the first pivot shaft can form a diagonal line of a virtual driving parallelogram which is reduced by the virtual driving parallelogram in an equal proportion, and the diagonal line of the virtual driving parallelogram is collinear with the diagonal line of the virtual driving parallelogram mechanism, so that the motion track of the power output end on the driving end can be amplified in an equal proportion by the parallelogram mechanism.

In some embodiments, the position of the third pivot axis is disposed on a side between the first pivot axis and the walking end proximate the first pivot axis. Preferably, the distance from the third pivot axis to the first pivot axis corresponds to 1/5-1/3 of the distance from the first pivot axis to the walking end. Thereby, the limb can be made to have a larger magnification.

In some embodiments, the walking end is disposed outside of the parallelogram mechanism. Specifically, the walking end is arranged on the first edge through the walking part. The walking end is fixedly arranged on or integrally formed with the walking part, and the walking part is fixedly arranged on or integrally formed with the first edge. Therefore, the obtained limbs have a bionic leg structure with at least two-fold characteristics, and the interference of a parallelogram mechanism when the walking end walks can be reduced. Preferably, the distance from the walking end to the nearest first pivot axis on the first side corresponds to the length of the second side or the fourth side. Therefore, the structure similar to the proportion of the animal legs can be obtained by adjusting the size proportion of the parallelogram mechanism and the walking end, so that the effects of coordination of limb structures and large walking amplitude are realized.

In some embodiments, the first pivot axis is disposed on the second pivot axis on the third side, and both are disposed coaxially; or the first pivot shaft is arranged on the connecting rod fixedly connected with the third edge, and the position of the first pivot shaft is arranged on the outer side of the parallelogram mechanism. The connecting rod is fixedly arranged on or integrally formed on the third edge. When the first pivot shaft is coaxially arranged on the second pivot shaft on the third side, if the walking end is also coaxially arranged on the second pivot shaft on the first side, the amplification capability of the limbs on the power output end is low, and the walking end is easily interfered by a parallelogram mechanism when walking; when the first pivot shaft is coaxially arranged on the second pivot shaft on the third side and the walking end is arranged on the first side through the walking part, the obtained limbs with the two-fold characteristic have larger magnification capability; when the first pivot shaft is arranged on the connecting rod fixedly connected with the third edge and the walking end is fixedly connected with the first edge through the walking part, the obtained limb with the three-folding characteristic can further amplify the motion trail of the power output end. Preferably, the distance from the first pivot axis to the nearest first pivot axis on the third side is not more than 2.5 times the distance between the two first pivot axes on the third side. Therefore, the phenomenon that the limb structure is unstable due to the fact that the distance from the first pivot shaft to the nearest first pivot shaft on the third edge is too long, namely the length of the connecting rod is too long, can be avoided.

In some embodiments, the first and third sides are short sides and the second and fourth sides are long sides that are longer than the short sides. Therefore, the amplification ratio of the motion trail of the limb to the power output end can be improved on the premise of not increasing the lengths of the first side and the third side. Preferably, the ratio of the length of the long side to the short side is 3-6: 1. therefore, on the premise of ensuring that the limb has a large amplification ratio, the problem that the stability of the limb movement is reduced due to the fact that the length ratio of the long side to the short side of the limb is large is solved.

In some embodiments, the power output end is pivotably provided on the second side or the fourth side by a third pivot shaft; or the power output end is arranged on the second side or the fourth side through a crank link mechanism, wherein the crank link mechanism comprises a first crank and a first link which are pivotally connected to a first pivot shaft, the first crank, the first link and the second side or the fourth side are sequentially and pivotally connected through a pivot shaft parallel to the first pivot shaft, the power output end is pivotally arranged on the first link through a third pivot shaft, the first crank and the first link are respectively parallel to two adjacent sides of the parallelogram mechanism, and the pivot shaft of the second side or the fourth side which is pivotally connected with the first link is not arranged on the second pivot shaft; or the power output end is arranged on the second side and the fourth side through the transmission rod, the power output end is pivotally arranged on the transmission rod through the third pivot shaft, the transmission rod is pivotally connected with the second side and the fourth side through the pivot shaft parallel to the first pivot shaft, and the transmission rod is parallel to the third side.

In some embodiments, the driving mechanism is configured such that, under the driving of the driving device, the power output end can form a half-moon-shaped motion track, the half-moon-shaped motion track is a closed curve formed by connecting an approximate straight line and at least one arc-shaped curve, the chord height ratio of the half-moon-shaped motion track is 3-6, and the linearity error of the approximate straight line section is less than +/-1.5%. The movement track of the walking end is also half-moon-shaped, so that the gravity center of the mechanical bionic foot can not be overlooked or fluctuated when the mechanical bionic foot walks, and the walking end can be ensured to walk stably.

In some embodiments, the drive mechanism is a crank-link slider mechanism comprising: a second crank with one end pivotally arranged on the bracket through a fourth pivot shaft parallel to the first pivot shaft; the first end of the second connecting rod is arranged on the other end of the second crank in a pivotable manner through a fifth pivot shaft parallel to the first pivot shaft, and the power output end is arranged at the second end of the second connecting rod; the sliding block is arranged at the third end of the second connecting rod; the sliding rail is arranged on the bracket and is matched with the sliding block; the sliding block can be arranged on the second connecting rod in a manner of rotating around a sixth pivot shaft parallel to the first pivot shaft relative to the sliding rail or the second connecting rod, and can also slide or roll along the sliding rail; the position of the sixth pivot shaft is arranged on one side, facing the first pivot shaft, of a connecting line of the fifth pivot shaft and the power output end. Therefore, the second crank of the driving mechanism can be driven by driving equipment such as a motor, when the second crank rotates around the fourth pivot shaft relative to the support under the driving of the motor, the first end on the second connecting rod is driven to do circular motion, and meanwhile, the sliding block at the second end on the second connecting rod is driven to do reciprocating motion along the sliding rail, so that the power output end obtains a half-moon-shaped walking track with two degrees of freedom. The length phase of the approximate straight line segment contained in the semilunar locus accounts for more than 120 degrees of the second crank rotation angle. In some embodiments, the slide rail is a linear slide rail, and has the characteristics of simple structure and low manufacturing cost. In other embodiments, the slide rail is a circular arc slide rail, so that an approximate straight line segment contained in a half-moon-shaped track obtained on the power output end has the characteristic of less straightness error.

In some embodiments, a connecting line between the fourth pivot axis and the fifth pivot axis is a first connecting line L1, a connecting line between the fifth pivot axis and the third pivot axis is a second connecting line L2, a perpendicular line from the sixth pivot axis to the second connecting line L2 is a third connecting line L3, and a perpendicular line from the fifth pivot axis to the third connecting line L3 is a fourth connecting line L4; wherein, the shape of slide rail is straight line or arc. In some preferred embodiments, when the shape of the slide rail is linear, the length ratio of L1, L2, L3, and L4 is 1:3.38:0.615: 2.77. In some preferred embodiments, when the shape of the slide rail is an arc, the length ratio of L1, L2, L3, and L4 is 1:3.3:0:2.83, and the length ratio of the radius of curvature R of the slide rail to L1 is 5.33: 1. Therefore, when the second crank rotates around the fourth pivot shaft relative to the bracket under the driving of the motor, the sliding block on the second connecting rod is driven to reciprocate along the sliding rail, so that the motion track of the power output end is in a half-moon shape.

In some embodiments, the mechanical bionic foot further comprises a driving device fixedly arranged on the support, and the driving device is used for driving the driving mechanism to move, so that the power output end moves according to a preset movement track, and then the walking end is driven to move by driving the limb to move. Specifically, when the driving mechanism is a crank-link slider mechanism, the driving device drives the second crank to rotate around the fourth pivot shaft, and the driving device may adopt a motor.

In order to effectively solve the problem that the weight and cost of each foot are increased due to the fact that each foot of the existing walking mechanism is driven by a plurality of motors, the inventor intensively studies a movement mechanism which realizes movement with two degrees of freedom by one motor; in order to ensure that the bionic foot can walk stably, the motion trail of the walking end needs to be ensured to be a half-moon-shaped trail from the perspective of bionics, therefore, the inventor explores a motion mechanism of the half-moon-shaped trail, and finally obtains the result of the mechanical bionic foot. The mechanical bionic foot scheme provided by the invention also adopts a single motor as power, can realize coordinated motion of two degrees of freedom, does not generate the phenomena of 'the gravity center of the frame is suddenly turned up and down and the height is fluctuated', and realizes 'stable walking' of the bionic foot; moreover, the structural form of the bionic foot limb is similar to the native form of an animal real leg, and the bionic foot limb has the characteristics of two-fold type or three-fold type, and has a simple structure; when walking, the stride is big, and the motion is extended. The specific scheme is that a parallelogram mechanism (or a mechanism formed by additionally arranging and expanding the parallelogram mechanism) is used as a limb of the bionic foot, so that the limb has an amplifying function; a crank connecting rod sliding block mechanism is used as a driving mechanism, and the driving mechanism can generate a half-moon-shaped motion track. The half-moon-shaped motion track generated by the driving mechanism is coupled to the power output end of the bionic foot limb, and the amplified half-moon-shaped walking track is obtained at the walking end of the limb through the amplification effect of the limb, so that the stable walking is realized.

Another object of the present invention is to provide a bionic walking robot.

The bionic walking robot comprises at least two mechanical bionic feet; the transmission mechanism is arranged on the bracket and transmits power to all the driving mechanisms; the driving device is arranged on the bracket and drives the transmission mechanism to move; wherein, all the brackets are integrated into a whole. The drive device may for example employ a motor. Therefore, the drive transmission mechanism can be driven by one drive device to drive a plurality of mechanical bionic feet to move, the weight of the bionic walking robot can be reduced, the cost is reduced, and the energy consumption of the bionic walking robot can be saved.

In some embodiments, the biomimetic walking robot comprises a phase change mechanism coupled to the transmission mechanism for adjusting the walking phase between different mechanical biomimetic feet.

Drawings

FIG. 1 is a schematic structural diagram of one embodiment of a mechanical bionic foot according to a first embodiment of the invention;

FIG. 2 is a schematic diagram of the structure of the mechanical bionic foot shown in FIG. 1;

FIG. 3 is a schematic structural diagram of another embodiment of the mechanical bionic foot according to the first embodiment of the invention;

FIG. 4 is a schematic structural diagram of a mechanical bionic foot according to a second embodiment of the invention;

FIG. 5 is a schematic structural diagram of a mechanical bionic foot according to a third embodiment of the invention;

FIG. 6 is a schematic structural diagram of a mechanical bionic foot according to a fourth embodiment of the invention;

FIG. 7 is a schematic structural diagram of a mechanical bionic foot according to a fifth embodiment of the invention;

fig. 8 is a schematic structural view of a biomimetic walking robot according to a first embodiment of the present invention.

Detailed Description

Several preferred embodiments of the present invention will be described in further detail below with reference to the accompanying drawings.

Figures 1 to 3 show schematically a first embodiment of a mechanical bionic foot according to the invention.

Referring to fig. 1 and 3, the mechanical bionic foot comprises a bracket 50, a first pivot shaft 202 arranged on the bracket 50, a limb pivotably arranged on the bracket 50 through the first pivot shaft 202, and a driving mechanism 40 arranged on the bracket 50, wherein the driving mechanism 40 is arranged such that a power output end on the driving mechanism can form a motion track with two degrees of freedom under the driving of a driving device, and the power output end is coupled to the limb; wherein, the limb is provided with a walking end 31, and the limb is arranged to amplify the motion trail of the power output end on the walking end 31 in equal proportion.

Illustratively, the structure of the limb is shown with reference to fig. 1 and 3, which includes a parallelogram mechanism 20 provided on a support 50 by a first pivot axis 202. Specifically, four sides of the parallelogram mechanism 20: the first side 21, the second side 22, the third side 23 and the fourth side 24 are sequentially and independently connected by the second pivot shaft 201 in a pivotable manner, and the fourth side 24 and the first side 21 are also independently connected by the second pivot shaft 201 in a pivotable manner, so that a deformable parallelogram with adjacent sides capable of mutually rotating around the second pivot shaft 201 is formed; the parallelogram mechanism 20 is formed with the first side 21 being opposite the third side 23, the second side 22 and the fourth side 24 being long sides, the first side 21 and the third side 23 being short sides, and the ratio of the length of the long side to the short side being about 3-6: 1.

Specifically, with continued reference to fig. 1 and 3, the walking end 31 is disposed on the first side 21, and more specifically, the walking end 31 is disposed on the first side 21 via the walking portion 30, the walking portion 30 is located outside the parallelogram mechanism 20, the walking portion 30 is integrally formed on the first side 21 of the parallelogram mechanism 20, and the walking end 31 is integrally formed at the bottom of the walking portion 30 for contacting with the road surface when the mechanical bionic foot walks; the second side 22 is located on the side of the fourth side 24 facing away from the walking end 31. In the preferred embodiment, the distance from the walking end 31 to the nearest first pivot axis 202 on the first side 21 corresponds to the length of the second side 22 or the fourth side 24.

Specifically, with continued reference to fig. 1 and 3, the first pivot shaft 202 is disposed on the third side 23, and more specifically, the first pivot shaft 202 is disposed on the third side 23 through a connecting rod 32 and located on a side of the parallelogram mechanism that is away from the walking end 31, and the connecting rod 32 is integrally formed on the third side 23, so as to obtain a limb with a "three-fold" feature. In the embodiment shown in fig. 1 and 3, the length of the first pivot axis 202 to the closest second pivot axis 201 on the third side 23 is not more than 2.5 times the distance of the two second pivot axes 201 on the third side 23. The connecting line of the first pivot axis 202 to the second pivot axis 201 where the third side 23 is hinged with the second side 22 (or the fourth side 24) is parallel to the connecting line of the second pivot axis 201 where the first side 21 is hinged with the second side 22 (or the fourth side 24) from the walking end 31; the first pivot shaft 202 is fixed to the bracket 50.

Specifically, as shown in fig. 1 and fig. 3, the power output end is pivotally disposed on the parallelogram mechanism 20 through a third pivot shaft 402, the third pivot shaft 402 is used as a joint point for transmitting power to the limb through the driving mechanism 40, and is also used as a coupling point for transmitting a motion trajectory of the power output end, and the third pivot shaft 402 is disposed on a connecting line from the first pivot shaft 202 to the walking end 31, a connecting line from the first pivot shaft 202 to the walking end 31 forms a diagonal line of the virtual walking parallelogram W, one side of the virtual walking parallelogram W passes through the walking end 31 and the second pivot shaft 201 hinged to the second side 22 or the fourth side 24 on the first side 21, the opposite side passes through the second pivot shaft 201 hinged to the second side 22 or the fourth side 24 on the first pivot shaft 202 and the third side 23, and the other two opposite sides are parallel to the second side 22; and taking a connecting line from the first pivot shaft 202 to the third pivot shaft 402 as a diagonal line, and reducing the connecting line in an equal proportion on the basis of the virtual walking parallelogram W to obtain a virtual driving parallelogram mechanism X with two adjacent sides parallel to the two adjacent sides of the virtual walking parallelogram W. More specifically, the third pivot shaft 402 is disposed on the second side 22 and is collinear with the two second pivot shafts 201 on the second side 22, and both the second pivot shafts 201 and the third pivot shaft 402 are disposed parallel to the first pivot shaft 202. Thus, when the power take-off moves, the connecting rod 32 is caused to rotate about the first pivot axis 202, and at this time, the parallelogram mechanism 20 is deformed under the restriction of the power take-off and the first pivot axis 202.

Referring to fig. 2, a connection line of a point F of the first pivot shaft 202 to a point G of the third side 23 of the second pivot shaft 201 is parallel to a connection line of the second pivot shaft 201 from a point J of the walking end 31 to a point H of the first side 21, a power output end is located at a cross point C of a straight line formed by connecting the first pivot shaft 202 and the walking end 31 and a GH line of the second side 22, a straight line formed by connecting the point G of the third side 23 of the second pivot shaft 201 and the point F of the first pivot shaft 202 extends towards a side where the walking end 31 is located, and intersects the line parallel to the GH line of the second side 22 of the parallelogram mechanism 20, passing through the J point of the walking end 31, at point I, extending the JH line in the direction of the first pivot axis 202, and intersects a line passing through the point F and parallel to the GH line of the second side 22 of the parallelogram mechanism 20 at a point S to form a virtual walking parallelogram W having a vertex of FIJS; c point crossing is performed to form a line parallel to the FI edge on the virtual walking parallelogram W, and the line intersects with the FS line at a V point to form a virtual driving parallelogram mechanism X with the vertex being FGCV; the connecting line of the third side 23 and the second pivot axis 201 closest to the first pivot axis 202 is a fifth connecting line L5, the connecting line of the point I and the point J is a sixth connecting line L6, the connecting line of the first pivot axis 202 to the third pivot axis 402 is a seventh connecting line L7, and the connecting line of the first pivot axis 202 to the walking end 31 is an eighth connecting line L8. Since FG/, GC/, L8 is the following regular length ratio L7 ═ FJ ═ FC ═ IJ ═ GC ═ GH ═ GC ═ L6: L5 ═ Y, where Y is a constant greater than 1, the motion trajectory of the J point of the walking end 31 can be enlarged by Y times compared with the motion trajectory of the C point of the power output end, and thus the "enlarged" walking trajectory can be obtained at the walking end 31 of the limb by controlling the motion trajectory of the power output end, and Y is 4 in the embodiment. Therefore, if the driving mechanism 40 can generate a motion trajectory with two degrees of freedom, the mechanical bionic foot can travel only by driving the driving mechanism 40 through one driving device (for example, a motor is adopted and is fixedly arranged on the bracket 50 when the motor is used), and a plurality of driving devices are not needed, so that the weight of the mechanical bionic foot is reduced, and the production cost of the mechanical bionic foot is reduced.

Referring to fig. 1 and 3, in a preferred embodiment, the location of the third pivot axis 402 is provided on a side between the first pivot axis 202 and the walking end 31 that is close to the first pivot axis 202. The length ratio of L7 to L8 is 1/5-1/3.

In order to ensure that the walking end 31 can walk stably, from the perspective of bionics, it is generally required to ensure that the motion trajectory of the walking end 31 is "half-moon shaped", that is, the motion trajectory of the power output end is also "half-moon shaped", wherein the "half-moon shaped" motion trajectory is a closed curve formed by connecting an approximate straight line and at least one arc-shaped curve, the chord height ratio of the half-moon shaped trajectory is 3-6, and the linearity error of the approximate straight line is less than +/-1.5%; to this end, the inventors set the drive mechanism 40 as an optimized crank link slider mechanism.

The first structure and the second structure of the crank-link slider mechanism are respectively shown in fig. 1 and 3, and comprise a second crank 41, a second link 42, a slide rail 43 and a slider 44; wherein, one end of the second crank 41 can rotate around the fourth pivot 403 fixed on the bracket 50; a first end of the second connecting rod 42 is hinged with the other end of the second crank 41 through a fifth pivot 404; the power output end is arranged at the second end of the second connecting rod 42 and is hinged with the second edge 22 through a third pivot shaft 402; the third end of the second connecting rod 42 is hinged with the sliding block 44 through a sixth pivot 405, and the sliding block 44 can reciprocate along the sliding rail 43 fixed on the bracket 50; the power take-off is provided on the side of the slide 44 remote from the second crank 41. The fourth pivot shaft 403, the fifth pivot shaft 404, and the sixth pivot shaft 405 are all disposed parallel to the first pivot shaft 202. The phase of the length of the approximate straight line is 120 DEG or more of the rotation angle of the second crank. The second structure of the crank connecting rod sliding block mechanism is different from the first structure in that: the first configuration of the slide rails 43 is linear (as shown in fig. 1); the second configuration of the slide rails 43 is arcuate (as shown in figure 3).

Specifically, a first connection line between the fourth pivot shaft 403 and the fifth pivot shaft 404 on the second crank 41 is taken as L1, a connection line between the third pivot shaft 402 and the fifth pivot shaft 404 on the second link 42 is taken as a second connection line L2, a vertical connection line between the sixth pivot shaft 405 and the second connection line L2 on the second link 42 is taken as a third connection line L3, that is, the sixth pivot shaft 405 is not located on a straight line connecting the third pivot shaft 402 and the fifth pivot shaft 404, a vertical connection line between the fifth pivot shaft 404 and the third connection line L3 is taken as a fourth connection line L4, and the sixth pivot shaft 405 is disposed on a side of the second connection line L2 close to the first pivot shaft 202. In a preferred embodiment of the crank-link slider mechanism of the linear slide of fig. 1, the length of the linear slide 43 is greater than twice the length of the first connecting line L1, taking the ratio of the lengths of L1: L2: L3: L4 to about 1:3.38:0.615: 2.77. In a preferred embodiment of the crank-link slider mechanism of the arcuate rail of fig. 3, the length ratio of L1: L2: L3: L4 is about 1:3.3:0:2.83, and the ratio of the radius of curvature R of the arcuate rail 43 to the length of the second crank 41, R: L1 is about 5.33: 1. The dimension parameters of the crankshaft slide block connecting rod mechanism are set according to the proportion and drawn as a structural schematic diagram shown in fig. 2, the motion trails of the power output end and the walking end 31 of the mechanical bionic foot are simulated, the motion trail of the power output end is K, the motion trail of the walking end 31 is L, the motion trail is shown in fig. 2, and the motion trail is obtained by amplifying the motion trail K by Y times.

When the driving mechanism 40 works, the driving mechanism 40 generally adopts a motor, and the motor drives the second crank 41 to rotate around the fourth pivot 403, so as to drive the first end of the second connecting rod 42 to make a circular motion and rotate around the fifth pivot 404, and simultaneously drive the slider 44 at the third end of the second connecting rod 42 to make a reciprocating motion along the slide rail 43; when the second connecting rod 42 performs the above-mentioned compound motion, a motion trajectory K (see fig. 2) with a "half-moon" shape is generated on the power output end (i.e. the third pivot shaft 402), and when the motion of the power output end drives the third edge 23 to rotate around the first pivot shaft 202 through the second edge 22, the third edge drives the traveling part 30 disposed on the first edge 21 to move together, and finally, the traveling trajectory L obtained on the traveling end 31 is Y times of the motion trajectory K.

In some embodiments, referring to fig. 2, the length ratio of the straight lines AB, FG, HJ, GH is 1:1.67: 4.83: 4.0 and the length of the second side 22 is 4.8 times that of the third side 23, the purpose of this arrangement being to ensure that the transmission pressure angle of the components is within a reasonable range when the mechanism is in operation.

As a preferred embodiment, to facilitate the installation of the mechanical bionic foot, referring to fig. 1 and 3, the mechanical bionic foot further comprises a bracket 50; the fourth pivot shaft 403, the slide rail 43 and the first pivot shaft 202 are all provided on the bracket 50. Further, a rotation motor that drives the crankshaft 41 to rotate about the fourth pivot shaft 403 may be further mounted on the bracket 50.

Figure 4 schematically illustrates a second embodiment of a mechanical bionic foot according to the invention.

Referring to fig. 4, the mechanical bionic foot in the present embodiment may be modified based on the first embodiment of the mechanical bionic foot, for example, the power output end on the limb is disposed on the fourth side 24 through the third pivot 402 instead of the second side 22, and the power input end 402 is still located at the intersection point of the connecting line from the first pivot 202 to the walking end 31 and the connecting line between the two second pivot 201 on the fourth side 24; and the connecting rod 32 and the walking part 30 are respectively positioned at two sides of the parallelogram mechanism 20 which are deviated from each other, so that the power output end can be positioned on the connecting line of the first pivot shaft 202 and the walking end 31.

It is also different from the mechanical bionic foot of the first embodiment in that: in this embodiment, the connecting rod 32 attached to the third side 23 is suitably shortened, i.e. equivalent to moving the parallelogram mechanism 20 to the side where the first pivot axis 202 is located, so that even if the power take-off is coupled to the fourth side 24, the magnification of the limb is not reduced. In particular, the connecting rod 32 is shortened by a length corresponding to the length of the third side 23, and thus by a distance corresponding to the parallelogram mechanism 20 being translated by the length of the third side 23 to the side where the first pivot axis 202 is located, so that the fourth side 24 coincides with the second side 22 before the movement.

The operation mode and the implementation effect of the mechanical bionic foot of the second embodiment obtained by adjustment on the basis of the first embodiment of the mechanical bionic foot are the same as those of the mechanical bionic foot of the first embodiment, and are not described herein again.

Figure 5 schematically illustrates a third embodiment of a mechanical bionic foot according to the invention.

Referring to fig. 5, the mechanical bionic foot in the present embodiment can be obtained by modifying the second embodiment of the mechanical bionic foot, mainly by adjusting the structure of the limbs. For example, the first pivot shaft 202 and a second pivot shaft 201 on the third side 23 and hinged to the second side 22 are coaxially arranged, that is, the first pivot shaft 202 and a pivot shaft on the third side 23 and hinged to the second side 22 are combined into a whole, and the third side 23 and the first pivot shaft 202 do not need to be connected through the connecting rod 32. The power output end is arranged on the fourth side 24 through the third pivot shaft 402 and is positioned on the connecting line of the first pivot shaft 202 and the walking end 31. The operation mode and the implementation effect of the mechanical bionic foot of the third embodiment obtained by adjusting the second embodiment of the mechanical bionic foot are the same as those of the mechanical bionic foot of the second embodiment, and are not described herein again.

According to the first to third embodiments of the mechanical bionic foot, when the power output end is arranged on the second side 22, the third side 23 must be pivotably connected with the first pivot shaft 202 through the connecting rod 32, so that the power output end can be located on the connecting line of the first pivot shaft 202 and the walking end 31. When the power output end is arranged on the fourth side 24, no matter whether the third side 23 is directly pivotally connected with the first pivot shaft 202 or pivotally connected with the first pivot shaft 202 through the connecting rod 32, the power output end can be positioned on the connecting line of the first pivot shaft 202 and the walking end 31. I.e. on which side of the parallelogram mechanism 20 the power take-off is arranged determines whether the connecting rod 32 can be eliminated.

In the first to third embodiments of the mechanical bionic foot, the power output end is directly arranged on the second side 22 or the fourth side 24. Of course, the power output end may be indirectly disposed on the second side 22 or the fourth side 24 as long as it can be ensured that the power output end can be located on the connecting line of the first pivot axis 202 and the walking end 31, for example, the mechanical bionic foot of the fourth embodiment of the present invention shown in fig. 6 and the mechanical bionic foot of the fifth embodiment of the present invention shown in fig. 7.

FIG. 6 schematically illustrates a fourth embodiment of a mechanical bionic foot according to the invention.

Referring to fig. 6, the mechanical bionic foot of the fourth embodiment can be modified based on the mechanical bionic foot of the first embodiment, and is mainly obtained by adjusting the structure of the limb, for example, the limb of the mechanical bionic foot of the present embodiment further includes, based on the limb of the mechanical bionic foot of the first embodiment, a first link 60 pivotally connected to one of the sides of the parallelogram mechanism 20 adjacent to the first side 21 through a seventh pivot 61, and a first crank 70 pivotally connected to the first link 60 through an eighth pivot 62, the other end of the first crank 70 is pivotally connected to the bracket 50 through a first pivot 202, the first link 60 is parallel to the link 32, and the first crank 70 is parallel to the second side 22; the power output end is not arranged on the second side 22 or the fourth side 24 of the parallelogram mechanism 20, but arranged on the first link 60 through the third pivot shaft 402, and particularly, the power output end is arranged on the C of the intersection point of the connecting line from the first pivot shaft 202 to the walking end 31 and the first link 60; the first pivot shaft 202, the third pivot shaft 402, the seventh pivot shaft 61 and the eighth pivot shaft 62 are all different in shaft and are all parallel to each other, and the first crankshaft 70, the first link 60 and the eighth pivot shaft 62 constitute a crank link mechanism.

Referring to fig. 6, a straight line formed by connecting a second pivot axis 201, which is formed by hinging a third side 23 and a second side 22, with a point F of a first pivot axis 202 extends toward a side where a walking end 31 is located, and intersects a line parallel to a GH line of the second side 22 of the parallelogram mechanism 20, which is made through a point J of the walking end 31, at a point I; the point C of the power output end is made into a line parallel to the line GH of the second side 22, and the line is compared with the line FI and the point M, so the length ratio of MC/GH/IJ meets the following rule L8: L7 is FJ: FC is IJ: MC is GH: GN is L6: L5 is Y, wherein Y is a constant larger than 1, and the motion track of the point J of the walking end 31 is Y times of the motion track of the point C of the power output end.

With continued reference to fig. 6, in the preferred embodiment, since the first link 60 is disposed parallel to the link 32, the first crank 70 is disposed parallel to the second side 22, the straight line formed by connecting the first pivot 202 and the eighth pivot 62 on the first crank 70 extends toward the side where the walking end 31 is located, and the extension line of the connection between the second pivot 201 hinged to the first side 21 and the second side 22 and the walking end 31 intersects at point P to form a virtual walking parallelogram W with a vertex FIJP; and drawing a line parallel to the FI edge on the virtual walking parallelogram W through the point C, and intersecting the FP line at the point O to form a virtual driving parallelogram mechanism X with the vertex FMCO. Therefore, OC/FI/PJ, L8: L7 ═ FJ: FC ═ FP: FO ═ GH: GN ═ L6: L5 ═ Y, wherein Y is a constant larger than 1, namely the motion trail of the J point of the walking end 31 can be Y times of the motion trail of the C point of the power output end.

Therefore, when the second crankshaft 41 is driven to rotate around the fourth pivot 403 by a motor through a driving device, the second crankshaft 41 drives the first end of the second connecting rod 42 to make a circular motion, and drives the slider 44 on the third end of the second connecting rod 42 to make a reciprocating motion along the slide rail 43, when the second connecting rod 42 makes the above-mentioned compound motion, the power output end arranged on the second connecting rod will generate a motion track with a "half-moon" characteristic, so as to couple to the point C arranged on the first connecting rod 60, drive the first connecting rod 60 to rotate around the eighth pivot 62, and drive the first crank 70 to rotate around the first pivot 202; the first link 60 rotates around the eighth pivot 62 and simultaneously drives the parallelogram mechanism 20 to rotate around the seventh pivot 61, so as to further drive the third side 23 of the parallelogram mechanism 20 to rotate around the first pivot 202, and finally, the walking track obtained on the walking end 31 is Y times of the motion track of the power output end.

It is also different from the mechanical bionic foot of the first embodiment in that: in this embodiment, the connecting bar 32 attached to the third side 23 is suitably lengthened to facilitate an increased range of motion of the limb.

The operation mode and the implementation effect of the mechanical bionic foot of the fourth embodiment obtained by adjustment on the basis of the first embodiment of the mechanical bionic foot are the same as those of the mechanical bionic foot of the first embodiment, and are not described herein again.

In the fourth embodiment of the mechanical bionic foot, if the third pivot 402 is disposed on the side of the second side 22 away from the walking end 31, the third side 23 must be provided with the additional connecting rod 32 to be pivotally connected with the first pivot 202, so that the power output end can be located on the connecting line between the first pivot 202 and the walking end 31. If the third pivot shaft 402 is disposed on the side of the second side 22 facing the walking end 31, the power output end can be located on the connection line between the first pivot shaft 202 and the walking end 31 no matter whether the third side 23 is additionally provided with the connecting rod 32.

FIG. 7 schematically illustrates a fifth embodiment of a mechanical bionic foot according to the invention.

Referring to fig. 7, the mechanical bionic foot of the fifth embodiment can be modified based on the mechanical bionic foot of the first embodiment, and is mainly obtained by adjusting the structure of the limbs, for example, the limbs of the mechanical bionic foot of the present embodiment further include, based on the limbs of the mechanical bionic foot of the first embodiment, a transmission rod 80 with both ends pivotally connected to the second side 22 and the fourth side 24 of the parallelogram mechanism 20 through a ninth pivot axis, and the transmission rod 80 is parallel to the third side 23; the power output end is arranged on a C of an intersection point of the transmission rod 80 and a connecting line from the first pivot shaft 202 to the walking end 31 through a third pivot shaft 402; the third pivot axis 402 and all of the ninth pivot axes are not coaxial and are all parallel to each other.

Referring to fig. 7, a straight line connecting the second pivot axis 201 on the third side 23 and the point F of the first pivot axis 202 extends toward the side where the traveling end 31 is located, and intersects a line parallel to the GH line of the second side 22 of the parallelogram mechanism 20 made at the point J passing through the traveling end 31 at a point I, and a point C passing through the power output end makes a line parallel to the GH line of the second side 22 and intersects the FI line at a point Q, so that QC/GH/IJ, L8: L7 ═ FJ: FC ═ IJ: GR ═ L6: L5 ═ Y where Y is a constant greater than 1.

Continuing to refer to fig. 7, the first pivot axis 202 is made straight along the GH line parallel to the second side 22 and toward the side where the walking end 31 is located, until the extension line of the connection of the second pivot axis 201 and the walking end 31 of the first side 21 intersects at a point U; the line connecting point C of the power take-off with the ninth pivot 81 extends to intersect line FU at point T. Therefore, the motion trail of the J point of the walking end 31 can be amplified as the motion trail of the C point of the power output end by using CT/UJ, QC FT, L8, L7F J F FT GR L6L 5Y.

It is also different from the mechanical bionic foot of the first embodiment in that: in the present embodiment, the connecting rod 32 attached to the third side 23 is suitably shortened, and the first pivot axis 202 provided on the connecting rod 32 is collinear with the two second pivot axes 201 on the third side 23; the running end 31 provided on the running part 30 is also collinear with the two second pivot axes 201 on the first side 21.

In the fifth embodiment of the mechanical bionic foot, since the third pivot 402 is arranged on the side of the second edge 22 facing the walking end 31, no matter the third edge 23 is additionally provided with the connecting rod 32, or the first pivot 202 and the second pivot 201 are directly and coaxially connected, the power output end can be located on the connecting line of the first pivot 202 and the walking end 31.

Therefore, when the second crankshaft 41 is driven to rotate around the fourth pivot 403 by the driving device, the second crankshaft 41 drives the first end of the second connecting rod 42 to make a circular motion, and drives the slider 44 at the third end of the second connecting rod 42 to make a reciprocating motion along the slide rail 43, when the second connecting rod 42 makes the above-mentioned compound motion, the power output end provided thereon will generate a motion track with a "half-moon" characteristic, so as to be coupled to the power output end provided on the transmission rod 80, so as to drive the transmission rod 80 to rotate around the ninth pivot 81, and further drive the third side 23 of the parallelogram mechanism 20 to rotate around the first pivot 202. The operation mode and the implementation effect of the mechanical bionic foot of the fifth embodiment obtained by adjustment on the basis of the first embodiment of the mechanical bionic foot are the same as those of the mechanical bionic foot of the first embodiment, and are not described herein again.

FIG. 8 schematically shows a biomimetic walking robot according to an embodiment of the present invention

Referring to fig. 8, the bionic walking robot comprises at least two mechanical bionic feet as described above, and a transmission mechanism arranged on the bracket 50 and used for driving all the driving mechanisms 40 to move; and a driving device which is arranged on the frame 50 and is used for driving the transmission mechanism to drive all the driving mechanisms 40 to move, wherein all the brackets 50 are integrated into a whole. Illustratively, the drive device employs a motor. For example, the transmission mechanism may be a gear transmission mechanism, a chain transmission mechanism, a belt transmission mechanism, or the like, which is commonly used in the art.

Therefore, the drive transmission mechanism can be driven by one drive device to drive a plurality of limbs to move, and the weight of the bionic walking robot can be reduced and the energy consumption of the bionic walking robot can be saved by reducing the use number of the drive device.

What has been described above are merely some embodiments of the present invention. It will be apparent to those skilled in the art that various changes and modifications can be made without departing from the inventive concept thereof, and these changes and modifications can be made without departing from the spirit and scope of the invention.

Claims

1. Mechanical bionic foot, its characterized in that includes:

a support;

a limb rotatable about a first pivot axis provided on the support;

the driving mechanism is arranged on the bracket, and a power output end on the driving mechanism can form a motion track with two degrees of freedom when the driving mechanism is driven by a driving device, and the power output end is connected to the limb; wherein,

the limbs are provided with walking ends, and the limbs are arranged to amplify the motion trail of the power output end on the walking ends in equal proportion.

2. The mechanical biomimetic foot according to claim 1, wherein the limb comprises:

the parallelogram mechanism can rotate around a first pivot shaft arranged on the bracket, the parallelogram mechanism is a deformable parallelogram formed by sequentially connecting a first edge, a second edge, a third edge and a fourth edge in a pivoting manner through a second pivot shaft, the third edge is arranged on the first pivot shaft, and the first pivot shaft and the second pivot shaft are arranged in parallel;

and a walking end provided on the first side; wherein,

the power output end is pivotally connected to the parallelogram mechanism through a third pivot shaft parallel to the first pivot shaft, and the position of the third pivot shaft is arranged on a connecting line of the first pivot shaft and the walking end;

the positions of the first pivot shaft, the third pivot shaft and the walking end are set to be in a virtual walking parallelogram taking a connecting line of the first pivot shaft and the walking end as a diagonal line, and the other two pairs of edges are parallel to the second edge.

3. The mechanical bionic foot according to claim 2, wherein the third pivot axis is positioned on a side of the walking end close to the first pivot axis; and/or

The walking end is arranged on the first edge through the walking part, and the walking end is arranged on the outer side of the parallelogram mechanism.

4. The mechanical bionic foot according to claim 2 or 3, wherein the third side is provided on the first pivot shaft through a second pivot shaft coaxially connected with the first pivot shaft; or,

the third edge is arranged on a first pivot shaft through a connecting rod, and the first pivot shaft is arranged on the outer side of the parallelogram mechanism.

5. The mechanical biomimetic foot according to claim 4, wherein the first and third sides are short sides and the second and fourth sides are long sides having a length greater than the short sides.

6. The mechanical bionic foot according to claim 4, wherein the power output end is pivotally arranged on the second side or the fourth side through a third pivot shaft; or,

the power output end is arranged on the second side or the fourth side through a crank connecting rod mechanism, wherein the crank connecting rod mechanism comprises a first crank and a first connecting rod which are pivotally connected to a first pivot shaft, the first crank, the first connecting rod and the second side or the fourth side are sequentially and pivotally connected through a pivot shaft parallel to the first pivot shaft, the power output end is pivotally arranged on the first connecting rod through a third pivot shaft, and the first crank and the first connecting rod are respectively parallel to two adjacent sides of the parallelogram mechanism; or,

the power output end is arranged on the second side and the fourth side through a transmission rod, the power output end is pivotally arranged on the transmission rod through a third pivot shaft, the transmission rod is pivotally connected with the second side and the fourth side through a pivot shaft parallel to the first pivot shaft, and the transmission rod is parallel to the third side.

7. The mechanical bionic foot according to claim 4, wherein the driving mechanism is configured such that, under the driving of the driving device, the power output end can form a half-moon-shaped motion track, the half-moon-shaped motion track is a closed curve formed by connecting an approximate straight line and at least one arc-shaped curve, the chord height ratio of the half-moon-shaped motion track is 3-6, and the straightness error of the approximate straight line is less than ± 1.5%.

8. The mechanical biomimetic foot according to claim 7, wherein the drive mechanism is a crank-link slider mechanism comprising:

a second crank with one end pivotally arranged on the bracket through a fourth pivot shaft parallel to the first pivot shaft;

a second connecting rod, the first end of which is pivotally arranged at the other end of the second crank through a fifth pivot shaft parallel to the first pivot shaft, and the power output end is arranged at the second end of the second connecting rod;

the sliding block is arranged at the third end of the second connecting rod;

the sliding rail is arranged on the bracket and is matched with the sliding block;

the sliding block can be arranged on the second connecting rod in a manner of rotating around a sixth pivot shaft parallel to the first pivot shaft relative to the sliding rail or the second connecting rod, and can also slide or roll along the sliding rail relatively.

9. The mechanical bionic foot according to claim 8, wherein a connecting line of the fourth pivot axis and a fifth pivot axis is a first connecting line L1, a connecting line of the fifth pivot axis and a third pivot axis is a second connecting line L2, a perpendicular line from the sixth pivot axis to the second connecting line L2 is a third connecting line L3, and a perpendicular line from the fifth pivot axis to the third connecting line L3 is a fourth connecting line L4; wherein the slide rail is in a linear or arc shape; in some preferred embodiments, when the shape of the sliding rail is linear, the length ratio of L1, L2, L3 and L4 is 1:3.38:0.615: 2.77; in some preferred embodiments, when the slide rail is arc-shaped, the length ratio of L1, L2, L3, and L4 is 1:3.3:0:2.83, and the length ratio of the radius of curvature R of the slide rail to L1 is 5.33: 1.

10. A bionic walking robot is characterized by comprising:

at least two mechanically biomimetic feet according to any of claims 1 to 9;

the transmission mechanism is arranged on the bracket and transmits power to all the driving mechanisms;

the driving device is arranged on the bracket and drives the transmission mechanism to move; wherein,

all the brackets are integrated.