WO2002011956A1

WO2002011956A1 - Multiple-legged walking apparatus

Info

Publication number: WO2002011956A1
Application number: PCT/KR2001/001317
Authority: WO
Inventors: Hai-Seong Jeong; Seung-Chul Lim
Original assignee: Robottec Co., Ltd.
Priority date: 2000-08-04
Filing date: 2001-08-03
Publication date: 2002-02-14
Also published as: AU2001275822A1; KR20020011709A

Abstract

The present invention provides a multiple-legged walking apparatus, which performs four-legged walking motion using closed multi-articulated link members. The multiple-legged walking apparatus of the present invention includes closed multi-articulated link members having a plurality of links in quadrilateral form, wherein each upper vertex of the link members is eccentrically connected to front or rear axis, and one vertical direction link is hinged on a plate, an end of said link, which reaches the ground as said front or rear axes rotates, draw an oval orbit, the driving force obtained by forming a pair of legs, positioned diagonally opposite each other, phase difference from another pair of legs. The present invention can prevent the leg joint from getting overload that is caused by a directly connected driving means, prohibit flowing over-currency, simplify overall structure, and reduce overall load as well.

Description

MULTIPLE-LEGGED WALKING APPARATUS

TECHNICAL FIELD

The present invention relates to a multiple-legged walking apparatus capable of driving and steering, and more particularly to a multiple-legged walking apparatus that performs walking motion using one driving means and free side-to-side steering using one driving means while walking.

BACKGROUND OF THE INVENTION Generally, a multi-legged walking robot system comprises legs having sensor and operating means such as a motor at each joint to generate a gait. In this case a hierarchical structure controller has to be installed, employing microprocessors to integrally control each operating device at a time, and the controller is designed firstly to generate a gait by integrating walking motions and cope with topographical changes of the walking velocity of the controller.

But, when individually installing operating devices to increase the degrees-of- freedom of each joint, the number of operating devices to be controlled increase, therefore, it is tricky to design a controller, which can perform stable gaits while walking in high speed. And the amount of kinetic data to be processed when performing operation and time required for the process are also problematic, and the increment of self-load of the devices leads to high manufacturing cost and high energy consumption. And heavy load acting onto a joint causes a durability problem due to overload.

At this, many studies have been conducted on various models performing more simplified walking motion, but there is no remarkable result due to difficulty in mechanism design that can mechanically embody a gait.

Meanwhile, referring to the walking patterns and the structures of legs of four- legged animals for embodying said mechanism, it can be found that each leg moves in cooperation with other legs drawing a regular orbit, and the pattern is conducted in a periodical and continual manner. If a mechanical device such as closed-type mechanical leg is adopted to embody the pattern, it can be possible to use the least number of driving means and to use a controller having simplified structure.

Therefore, if said problem is solved, a multi-legged walking apparatus can adapt to an irregular ground as good as a four-legged walking animals, can travel in a plane ground like a wheeled vehicle, can transport heavy freight, can easily change the velocity as well as easily steer, can be economic, and can have energy efficiency.

DISCLOSURE OF INVENTION

An object of the present invention is to provide a multiple-legged walking apparatus. In solving conventional problems mentioned above, the objective of the present invention is to provide an effective multiple-legged walking apparatus having one driving means for walking, which performs walking motion, and one driving means for steering, which permits free steering while walking.

The present invention provides a multiple-legged walking apparatus comprising: front and rear axes driven by receiving power from a power source; a plurality of closed multi-articulated link members made of a plurality of links to form quadrilaterals; a plurality of plates connected to both ends of said front and rear axes and connecting said closed multi-articulated link members, wherein each upper vertex of said closed multi-articulated link members is eccentrically connected to said axes respectively, and one vertical-direction link is hinged on said plate, and one end of said link members, which reaches to the ground while said front and rear axes rotate, draws an oval orbit, wherein driving force is generated when a pair of legs, which are diagonally opposite each other, form phase difference from another pair of legs which are diagonally opposite. Also, said front and rear axes are connected perpendicular to the main axis, which is operated by a power source, and are operated in cooperation with a pair of bevel gears.

The multiple-legged walking apparatus may comprise a plurality of cranks, which are circular shape and rotate with an axis, wherein each of the center of said cranks is fixed at said front and rear axes, and each upper vertex of said closed multi- articulated link members may be eccentrically connected to the circumferences of said cranks.

Preferably, two pairs of legs located diagonally opposite to each other are positioned with 180° phase difference, and the center of gravity of said multiple legged walking apparatus is formed at the crossing point of the two diagonals of the pairs to enable safe performance of a walking motion.

In a preferred embodiment, said closed multi-articulated link members comprise horizontal links at upper and lower parts and vertical links at front and rear parts, and the links are expanded to make one end of horizontal link of said lower part met the ground. Let θ i is an angle between the horizon and the extended line from the center of said front or rear axis to the upper vertex of said closed multi-articulated link, and li is the length of the extended line, θ ₃ is the angle between the horizon and each vertical link, 1₅ is the length of the vertical link, θ 5 is the angle between the horizon and each horizontal link, and 1₃ is the length of the lower horizontal link, the orbit OE of one end of said horizontal or vertical link satisfies OE = \_χg ' + /₅ g' ³ + ₃ ^ ⁵ . In another embodiment, said closed multi-articulated link comprises upper and lower horizontal links and front and rear vertical links, and one end of said front or rear vertical link extends to the ground. Let θ ι is the angle between the horizon and the extended line from the center of said front or rear axis to the upper vertex of said closed multi-articulated link, U is the length of the extended line, θ ₃ is the angle between the horizon and each vertical link, 1₅ is the extended length of said front or rear vertical link, θ ₅ is the angle between the horizon and each horizon link, and 1₃ is the length of the horizon link, the orbit of one end of said horizontal or vertical link OE satisfies

Preferably, let 1 is the length of said multiple-legged walking apparatus, h is the height of it, and b is the width of it, pitching angle θ_γ and rolling angle θ_x of said multiple-legged walking apparatus satisfy θ_γ ≤ tan^-1 (llh) and θ_x ≤ tan^-1 (blh) .

The present invention provides a multiple-legged walking apparatus comprising: a front axis rotating by transferred power; a plurality of link members connected to form quadrilaterals; a plurality of plates connecting said link members and both ends of said front axis; a driving means opening and closing said plates in cooperation with steering bars, wherein said driving means opens all of said plates toward both ends of said front axis when the link members located in opposite side to steering direction reach the ground, and closes all of said plates when the link members located in the same side with steering direction reach the ground such that the multiple-legged walking apparatus performs steering by repetitively performing the activities.

Preferably, said driving means comprises a linear-shape steering piece, wherein both ends of said steering piece are connected to said steering bars, and both ends of said steering bars are connected to front-lower part of said plates forming an acute angle with said front axis such that said steering bars push said plates to both ends of said front axis when said steering piece rotates 90°, and said steering bars force said plates to return to initial position when said steering piece rotates 180°.

Preferably, said driving means comprises: a motor; a worm gear connected to said motor; upper gears geared with both sides of said worm gear; lower gears positioned below said upper gears and geared with said upper gears at inner side; solenoids which force said lower gears to move up-and-down, controlling power transmission between the two gears; and cranks connected to said lower gears and the lower part of said solenoids, wherein said steering bars are eccentrically connected to the circumferences of said cranks, and operate simultaneously to open or close the plates connected to said front axis.

Selectively, each distal end of said steering bars far from said driving means, is connected to at least one link, and each end of said link, which is not connected to said steering bar, is fixedly installed forming an acute angle with said steering bar, and the connective part between said steering bar and said link is connected to a spring, of which end is fixedly installed, such that said plate automatically return to initial position.

According to the present invention described hereinabove, as the body can be moved forward and side to side steering at a time by the controllers and power transmitted from two driving means installed in the body, the multiple-legged walking apparatus of the present invention can prevent a risk of overload and over currency caused by driving means that are directly connected to leg joints as used before, reduce the overall self load, simplify the overall structure, dramatically reduce energy consumption, and save manufacturing cost And according to the present invention, as all of four cranks that are operated for walking motion can receive power from same power transmitter, the number of driving means required for walking motion is dramatically reduced to one.

And also, as the portion for supporting the body is formed by link structure, even if a system error occurred stops device operation, the shape of the body and walking motion can be safely secured.

The apparatus of the present invention can work moderately on the sands or swampy ground or on uneven ground having obstacles.

BRIEF DESCRIPTION OF THE DRAWINGS The preferred embodiment of the present invention is described in relation to the following drawings.

FIG. 1 is a plan view of a multiple-legged walking apparatus according to the present invention.

FIG. 2 is a perspective view of the multiple-legged walking apparatus according to the present invention.

FIG. 3 is a front view illustrating the principle of a closed multi-articulated link members according to the present invention.

FIG. 4a is a diagram illustrating the trace of the movement of the closed multi- articulated link members according to the present invention, and FIG. 4b is a diagram illustrating the oval orbit of an end of link members according to the present invention. FIG. 5 is a diagram illustrating walking cycles of each leg and steering angle of the multiple-legged walking apparatus according to the present invention.

FIG. 6 is a diagram illustrating the movement of the body of the multiple- legged walking apparatus according to the present invention. FIG. 7 is a plan view illustrating the steering movement of the multiple-legged walking apparatus according to the present invention.

FIG. 8 is an exploded perspective view illustrating an example of the composition of the steering part of the multiple-legged walking apparatus according to the present invention.

BEST MODE FOR CARRING OUT THE INVENTION

FIG 1. and FIG. 2 are a plan view and a perspective view of a multiple- legged walking apparatus of the present invention respectively. And as shown in FIG. 1 and FIG.2, the multi-legged walking apparatus 1 can move and steer a body 2 back- and-forth and side-to-side at a time using driving force obtained from driving means for walking 11 and steering 21, and the multi-legged walking apparatus 1 comprises a body 2, a walking part 10, a steering part 20 and a control part 30.

In other words, the walking part 10 comprises a first driving means 11, a main axis 12, a front axis 14, a rear axis 15 and a plurality of legs LI, L2, L3, L4. And said first driving means 11 is installed in the body 2 in parallel with the body 2 and the main axis 12, and comprises a motor means which can freely rotate said main axis in clockwise or counter clockwise direction, wherein a passive gear 12a is installed in the middle of said main axis 12, and the passive gear 12a is geared with a driving gear 11a.

And at the front and rear ends of said main axis 12, driving bevel gears 12b and 12c are respectively attached to passive bevel gears 14a and 15 a, which are installed in the middle of said front and rear axes 14 and 15, such that said front and rear axes 14 and 15, which are installed in perpendicular to said main axes 12, rotate in the same direction.

Wherein gears are employed to transfer the rotating force of said first driving means 11 to the main axis 12 and to transfer the rotating force of the main axis 12 to the front and rear axes 14 and 15, but other power transforming means such as belt or pulley and the like can be used variously.

And, the left and right ends of said front axis 14 are connected to the ends of connective bars 16a and 16b, through a constant velocity universal joint, permitting rotating and angular movement, and each end of said connective bars 16a and 16b is connected to the constant velocity universal joint, which is a connecting device 17 of first and second front cranks 17a and 17b that are exposed to the inner side through a connective hole 22 of first and second front plates 22a and 22b by using a pin means 16 permitting rotating. Meanwhile both left and right ends of said rear driving axis 15 are connected to the centers of the first and second rear cranks 17c and 17d through the connective hole 22 of first and second rear plates 22c and 22d.

Wherein said connective hole 22 comprises a bearing means (not shown) to enable easy rotation, and said front and rear axes 14 and 15 are supported by a plurality of bearing means (not shown) which are fixedly installed at the body 2 to enable easy rotation.

Meanwhile, said fist and second front and rear cranks 17a, 17b, 17c, 17d installed at both ends of the front and rear sides of the body 2 to permit rotation by obtaining driving force from said first driving means 11, are respectively connected to the first and second front and rear legs LI, L2, L3, L4, which are constructed by a first, second, third, forth link members 18a, 18b, 18c, 18d in quadrilateral shape permitting each connection of links to rotate, and first, second, third, forth link members 18a, 18b, 18c, 18d is assembled for the bottommost end 18 of link members lSd firstly reach the ground when said first and second front and rear cranks 17a, 17b, 17c, 17d rotate, to draw an oval orbit. In other words, the ends of first and third link members 18a, 18c of said first and second front and rear legs LI, L2, L3, L4 are linked at the circumferences of said first and second front and rear cranks 17a, 17b, 17c, 17d by pin means pi, p2, p3, p4, which are fixedly installed at the circumferences of the cranks, being enabled circular motion. And the ends of the second and forth link members 18b, 18d, which are connected to the ends of said first and third link members 18a, 18c respectively, are connected permitting rotating motion. Meanwhile, the fixed pins si, s2, s3, s4 are fixedly installed at said first and second front and rear plates 22a, 22b, 22c, 22d and connected to the middle point of said second link members 18b permitting rotating motion. And the first and second front and rear legs LI, L2, L3, L4, which are installed at said first and second front and rear cranks 17a, 17b, 17c, 17d, are installed in the way that diagonally confronting legs are mirrored opposite each other, and the first and third link members 18a, 18c of the first and second front legs LI, L2, which are installed at said first and second front cranks 17a, 17b respectively, are connected to the pin means pi of the first front crank 17a and the pin means p2 of the second front crank 17b, which pins are positioned with 180° phase difference. And the first and third link members 18a, 18c of the first and second rear legs L3, L4, installed at the first and second rear cranks 18c, 18d respectively, are connected to the pin means p3, p4, which are positioned with 180° phase difference. And the first front leg LI is diagonally opposite to the first rear leg L3 having the same phase, meanwhile, the second front and rear legs L2 and L4 are diagonally opposite with each other having the same phase, but the first front and rear legs LI and L3 are positioned with 180° phase difference from the second front and rear legs L2 and L4.

And the end of the forth link members 18d of said first and second front and rear legs LI, L2, L3, L4 is extended to have the bottommost end 18, which can firstly reach the ground and draw an oval orbit.

FIG. 3 is a front view illustrating the principle of a closed multi-articulated link members according to the present invention. According to the principle, when the driving crank 17a is rotating, it outputs only one fixed pattern. This can be confirmed by substituting the number of link n = 6, the number of lower pair L = 7, the number of higher pair H=0 into the Grubler's formula that the degrees-of-freedom is only one as follows;

F = 3(n-1)-2L-H = l

Meanwhile, referring to FIG. 3, when representing all the lengths of the links comprising the closed multi-articulated link members and absolute angular displacement into polar forms of complex numbers, the result is as follows; OA = /₁ ¹ , AB = /₂/² , AC = /_S/'

M = (/₃ +/₄) ⁴ . CD = i_6e ^w> , BF = /₃ , OF = /₀/°

And according to the loop equation, AB + BD = AC +CD. Using the same method, following equation can be produced from the four- articulated link members, which have hinge points O, A, B, F. OA + AB + BF = OF

If θ o is a constant and θ ι(t) is rotation angle of a crank, two real number equations relating to θ ₂ and θ ₄ are produced as follows; /, cos#_ι + /₂ cos#₂ + /₃ cos0₄ = /₀ cos0₀ _j sin Θ_λ + 1₂ sin θ₂ + /₃ sin θ₄ = /₀ sin θ₀

And also, the orbit of the point E, which is end point of a leg, can be calculated according to the following equation;

^OE=I_le ⁺l,e^{Ut +}Q,⁺l₇ ⁾e°' According to the above equations, when the lengths of each link members are lo=73, lι=ll, 1₂=61, 1₃=38, 1₄ =76, 1₅=104, 1₆=50, 1₇=85 mm and θ ₀ = 5π 14 rad, as the crank 17a of FIG. 3 rotates with a uniformed circular motion in counter-clockwise direction, the locations of a leg and the point E moves as shown in FIG. 4, and the movement forms basic gait pattern necessary for walking. FIG. 4a shows a time-chart illustrating the process of a gait generation by operating the proposed link system.

FIG. 4b is a diagram illustrating the trace of the bottommost end of the link members, point E, of FIG. 3. The arrow illustrates the moving direction of the end of a leg. And during the 'a → b' phase, a leg takes off the ground drawing an orbit in the air and lands on the ground, while during the 'b → a' phase, the end of a leg stops sticking closely to the ground and the body gets driving force as reaction. Meanwhile, since the orbit is illustrated on a regular interval basis, referring to the whole orbit, it is easily known without further explanation on the velocity when the end of a leg moves fast, and this can be utilized in designing walking orbit, which can minimize an impact. In an embodiment, the relations between width b, length 1, height h, rolling and pitching angle of the apparatus 1 can be output. When the right and left side of the orbit of each leg is asymmetric, or there is a difference between the two sides of the orbit due to the assembly problem, even if the center of gravity is in the center of the body and the motion of each leg is well controlled by the position controller of the driving means regardless of the degree of a load, four of the motions except translation and yawing out of the six degrees of freedom are caused due to connective structures between the body and the legs.

Let fj(t) (i=l,2,3,4) be the orbits of each leg on or under the ground and subscript x and z be the displacement elements of traveling and vertical directions, the vertical displacement z, traveling displacement x, pitching angle Θ_γ and rolling angle θ_x are s follows; z=(flz + f3z)/2 or (flz + f4z)/2 x=(flx + f3x)N/2 or (f2x + f4x)N/2 θ_γ = (flz - f2z)/l or (£2z - f4z)/l θ_x - (flz - Qz)lb or (£2z - f4z)/b

Wherein N represents the number of walking cycle. To prevent the body of a robot described above from overturn while the center of gravity is in the center of the body, in other words, to certify safety, when the vertical position of the center of gravity is at h/2, the value of pitching or rolling angle should satisfy θ_γ < tan^-1 (//A) and θ_x ≤ tm^~l (b/h) .

Meanwhile, when manufacturing a robot or loading freight, the center of gravity is generally located at the center of the body, which is the crossing point of the two diagonals of the four legs. Providing that the legs are manufactured in proper size, said crossing point is formed within permissible area permitting more or less errors, and more than 2 points are supported, which satisfies said assumption.

And according to the preferred embodiment, while a pair of legs is in the air, another pair of legs should be on the ground; otherwise, four legs will be on the ground at the same time or instantaneously in the air all together, which leads to falling down to the ground. Therefore, if diagonally opposite front and rear legs are moving with 180° phase difference, as shown in FIG. 4, it is preferable that the left and right side of the orbit are symmetric.

According to another embodiment, the bottom end of the second link members 18b of said first and second front and rear legs LI, L2, L3, L4, is extended to have a bottommost end 18, which can firstly reach the ground drawing an oval orbit. This shows that various walking patterns can be presented according to the method of installing links, in other words, transforming this apparatus to spider type and the like be easily achieved.

But, in various walking patterns, basic method for generation a gait is the same. In other words, if the phase of the first front leg LI is the same as that of the second rear leg L3, and the phases of the other two legs are the same each other, and the two groups of legs are positioned with 180° phase difference, walking effect can be obtained.

In the above embodiment, when the body 2 having the first and second front legs LI, L2 and the first and second rear legs L3, L4 is to proceed forward, as shown FIG. 1 and FIG. 2, external power should be supplied to the first driving means 11, which is installed in the body 2 permitting the main axis 12 to rotate in counter clockwise direction, at this time, the front and rear axes 14, 15 geared at the front and rear ends of said main axis 12, rotate in counter clock-wise direction. By doing this, the first and second front and rear cranks 17a, 17b, 17c, 17d, which are installed in the left and right side of said front and rear axes 14, 15, can be rotated in the same direction simultaneously.

In this case, the first front and rear legs LI, L3, which are diagonally opposite each other, are installed at the first front and rear cranks 17a, 17c with the same phase, and the other second front and rear legs L2, L4 are installed at the second front and rear cranks 17b, 17d with 180° phase difference from said fist front and rear legs LI, L3, and the middle of the second link members 18b is connected to the pins si, s2, s3, s4 permitting rotation, therefore, the bottommost end 18, which is extended from the forth link members 18d of said first and second front and rear legs LI, L2, L3, L4, as shown in FIG. 3, moves drawing an oval orbit. At this time, if the bottommost end 18 of said first front and rear legs LI, L3 are in the air, the second front and rear legs L2, L4 are on the ground generating driving force, and in contrast, if the bottommost end 18 of said second front and rear legs L2, L4 are in the air, the first front and rear legs L2, L4 are on the ground generating driving force. As shown in FIG. 6, the body 2 comprising said first and second front and rear legs LI, L2, L3, L4 can move forward with periodical up-and-down motion powered by the driving force gained by continuous rotating operation of said first and second front and rear cranks 17a, 17b, 17c, 17d, providing that under the ground orbits of all legs are identical with each other and the left and right side of the orbit is symmetric. Of course, said body 2 can move backward when the driving axis of said first driving means 11 is rotated in reverse direction and performing above mentioned procedure in reverse order.

And, as the first front and rear legs LI, L3, which are diagonally opposite with the same phase, are located with 180° phase difference from the second front and rear legs L2, L4, which are diagonally opposite with the same phase, during the time when the bottommost end 18 of said first front and rear legs LI, L3 is in the air, the bottommost end 18 of said second front and rear legs L2, L4 can be attached to the ground at a time, and the time spent for moving the pair of legs LI and L3 is equal to the time for moving another pair of legs L2 and L4. Meanwhile, as shown in FIG. 1 and FIG. 2, the steering part 20, which steers the body 2 in side-to-side direction while walking, comprises a second driving means 21 that is fixedly installed in the body 2, and the center of a steering piece 23 is connected to the driving axis of said second driving means 21 permitting rotation of the steering piece in clockwise or counter clockwise direction. And it is preferable that said second driving means 21 is equipped with a sub-motor means, which permits said steering piece 23 to freely perform angle movement.

And one end of said steering piece 23 is connected to one end of a first steering bar 24a, and another end of said first steering bar 24a is connected to the inner side of said first front plate 22a, meanwhile, another end of said steering piece 23 is connected to one end of a second steering bar 24b, and another end of said second steering bar 24b is connected to the inner side of the second front plate 22b. Wherein, one end of said steering piece 23 connected to said first steering bar 24a and another end of said steering piece 23 connected to said second steering bar 24b are positioned with 180° phase difference. Therefore, if the driving axis of said second driving means 21 rotates in clockwise or counter clockwise direction, the first and second front plates 22a and 22b, which are connected to said first and second steering bars 24a and 24b respectively, perform keying movement around the connecting device 17 of the first and second front crank 17a, 17b forcing the front side of the body 2 to steer side-to-side. As shown in FIG. 8, according to another embodiment regarding said steering part 20, the second driving means 61 is fixedly installed at front-inner side of the body 2. Preferably said driving means is a motor 61. A worm gear 62 is installed at one end of a driving axis 63 of said driving means, and both sides of the worm gear 62 are symmetrically geared with worm wheels 64, which are upper gears. Under the worm wheels 64, lower gears 65 are installed, which are moved up-and-down by solenoids 66 that are installed to control power transfer. When power is transferred, gears 65a installed upon lower gears 65 are geared with gears 64a that are installed at the bottom side of the worm wheel 64, which are upper gears.

When power is on, the solenoids 66 force said lower gears 65 to move upward to gear with the upper gears 64, and when power is off, the solenoids 66 force said lower gears 65 to move downward to detach from the upper gears 64. Cranks 67 are positioned below the lower gears 65 sharing the same axis with the lower gears, and steering bars 68 are hinged at the circumferences of the cranks 67 to eccentrically rotate. Said cranks 67, lower gears 65, upper gears 64 and solenoids 66 are installed symmetrically with respect to the worm gear 62, and a support gear 70 is installed in the middle of the cranks 67.

Preferably, the steering bars can perform smooth return by fixedly attaching springs 71 between the front side of the body 2 and one end of steering bars 68. According to said preferred embodiment, if said body 2 is to be steered to the left while walking as shown FIG. 7a, the driving axis of the second driving means 21 has to be rotated in counter clockwise direction by the electric signal transferred from a controller 31 when the bottommost end 18 of the second front leg L2, which is located at opposite side to the steering direction, is reaching the ground. Wherein how much said second driving means 21 is to be rotated is determined by said controller 31 to the extent that the body is to be steered, and the steering angle can be freely adjustable. Wherein α is steering angle.

As described above, when the driving axis of said second driving means 21 rotates in counter clockwise direction forcing the steering piece 23 to rotate to a predetermined degree, the first and second steering bars 24a and 24b linked at the left and right ends of said steering piece 23 are simultaneously drawn to the steering piece 23, and the first and second front plates 22a and 22b, which are connected to one end of said steering bars 24a and 24b respectively, rotate simultaneously in the left direction. At this time, the first and second front legs LI, L2, which are connected to the first and second front cranks 17a, 17b that are assembled in the circumference of said first and second front plates 22a, 22b, rotate at a time. This angular rotation is enabled because the space between each of connecting devices 17, which are projected through the connective hole 22 of said first and second front plates 22a, 22b, of the first and second front cranks 17a and 17b and the connective bars 16a, 16b, and between both ends of said front axis 14 and the connective bars 16a, 16b are connected through the constant velocity universal joint, such as to enable angular rotation required for walking and steering.

And as shown in FIG. 7b, when the bottommost end 18 of second front leg L2 is detaching from the ground while said body 2 performs walking motion and the bottommost end 18 of the first front leg LI is landing to the ground, if the driving axis of said second driving means 21 rotates in clockwise direction till the position of the driving axis returns to initial position, said first and second front plates 22a and 22b are placed at the same axis with the first and second rear plates 22c and 22d, wherein if said first and second front plates 22a and 22b are completely closed by discontinuing power transmitted to said second driving means 21, the body 2 can be steered.

The method of steering said body 2 to the right direction is just opposite to the way described in the above, which is, when the first front leg LI is on the ground and the second front leg L2 is in the air, to rotate the driving axis of said second driving means 21 in clockwise direction. In the preferred embodiment, as shown in FIG. 1, the control section 30 is installed to control walking motion and steering the body 2, wherein the control party comprises a controller 31 connected electrically to the encoder, which identifies the number of rotating of the first driving means 11 that rotates said first and second front cranks 17a and 17b and the first and second rear cranks 17c and 17d by using the main axis 12, front axis 14 and rear axis 15. And said controller 31 is connected electrically to the second driving means 21 to control angular rotation of said first and second front plates 22a and 22b by properly adjusting rotation angle of said steering piece 23.

And in the body 2, a charge means 35 charged with required electric power can be comprised to supply said first and second driving means 11, 21 with power for a predetermined time.

Wherein, the velocity and walking distance of the body 2 can simply and properly be controlled by the controller 31, which receives signals from the encoder 32 that identifies the number of rotation of the driving axis of said first driving means 11 and orders the determined number of rotation.

At this time, said controller 31 controls steering angle by adjusting the degree of rotation of the second driving means 21, which force said first and second front plates 22a and 22b to angularly rotate based on the data on the amount of rotation of the main axis 12, which data is acquired from the encoder 32 connected to the first driving means 11 that is operating while the body 2 is walking.

The present invention described in relation to the preferred embodiment illustrating drawing figures can be reconstructed and changed in many ways within the scope of spirits and the technical field provided by the claims of this invention by any person skilled in the art.

INDUSTRIAL APPLICABILITY

The present invention relates to a multiple-legged walking apparatus capable of driving and steering, and the multiple-legged walking apparatus performs walking motion using a driving means and free side-to-side steering using another driving means while walking.

Claims

CLIAMS:

1. A multiple-legged walking apparatus comprising: front and rear axes driven by receiving power from power source; a plurality of closed multi-articulated link members made of a plurality of links to form quadrilaterals; and a plurality of plates connected to both ends of said front and rear axes and connecting said closed multi-articulated link members, wherein each upper vertex of said closed multi-articulated link members is eccentrically connected to said axes respectively, and one vertical-direction link is hinged on said plate, and one end of said link members, which reaches to the ground while said front and rear axes rotate, draws an oval orbit, wherein driving force is generated when a pair of legs, which are diagonally opposite each other, form phase difference from another pair of legs which are diagonally opposite.

2. The multiple-legged walking apparatus according to claim 1, said front and rear axes are connected perpendicular to a main axis, which is operated by one receiving power source, and are operated in cooperation with a pair of bevel gears.

3. The multiple-legged walking apparatus according to claim 1, further comprises a plurality of cranks, which are circular shape and rotates with an axis, wherein the center of said crank is fixed at said front and rear axes, and each upper vertex of said closed multi-articulated link members is eccentrically connected to the circumferences of the cranks.

. The multiple-legged walking apparatus according to claim 1, two pairs of legs located diagonally opposite to each other are positioned with 180° phase difference.

5. The multiple-legged walking apparatus according to claim 1, the center of gravity of said multiple-legged walking apparatus is formed at the crossing point of the two diagonals of the pairs to enable safe performance of a working motion.

6. The multiple-legged walking apparatus as in any of claims 1-5, said closed multi- articulated link members comprise horizontal links at upper and lower parts and vertical links at front and rear part and the links are expanded to make one end of horizontal link of said lower part meet the ground.

7. The multiple-legged walking apparatus according to claim 6, the orbit OE of an end of said horizontal or vertical link satisfies OE = /, g' ^l + \_5β ³ + /₃g' ⁵ , wherein θ is an angle between the horizon and the extended line from the center of said front or rear axis to the upper vertex of said closed multi-articulated link, and li is the length of the expanded line, θ ₃ is the angle between the horizon and each vertical link, 1₅ is the length of the vertical link, θ ₅ is the angle between the horizon and each horizontal link, and 1₃ is the length of the lower horizontal link.

8. The multiple-legged walking apparatus as in any of claims 1-5, said closed multi- articulated link members comprise upper and lower horizontal links and front and rear vertical links, wherein one end of front or rear vertical links is extended to contact the ground.

. The multiple-legged walking apparatus according to claim 8, the orbit OE of an iθ ϊQ iθ end of said horizontal or vertical link satisfies OE = ,g ' + /₅£? ' ⁺ e ' '■_> wherein θ ι is an angle between the horizon and the extended line from the center of said front or rear axis to the upper vertex of said closed multi-articulated link, and \_\ is the length of the expanded line, θ ₃ is the angle between the horizon and each vertical link, 1₅ is the length of the vertical link, θ ₅ is the angle between the horizon and each horizontal link, and 1₃ is the length of the lower horizontal link.

10. The multiple-legged walking apparatus according to claim 1, pitching angle θ_γ and rolling θ_x satisfy θ_r ≤ tan^-1 (///?) and θ_x < \an^~ (blh) , wherein 1 is the length, h is the height, and b is the width of said multiple-legged walking apparatus.

11. The multiple-legged walking apparatus comprising a front axis rotating by transferred power; a plurality of link members connected to form quadrilaterals; a plurality of plates connecting said link members and both ends of said front axis; and a driving means opening and closing said plates in cooperation with steering bars, wherein said driving means opens all of said plates toward both ends of said front axis when the link members located in opposite side to steering direction reach the ground, and closes all of said plates when the link members located in the same side with steering direction reach the ground, such that the multiple-legged walking apparatus performs steering by repetitively performing the activities.

2. The multiple-legged walking apparatus according to claim 11, said driving means comprises a linear-shape steering piece, wherein both ends of the steering piece are connected to said steering bars, and both ends of said steering bars are connected to the front-lower part of said plates forming an acute angle with said front axis such that said steering bars pushes said plate to both end of said front axis when said steering piece rotates 90° and forces said plate to return to initial position when said steering piece rotates 180°.

13. The multiple-legged walking apparatus according to claim 11, said driving means comprises a motor; a worm gear connected to said motor; upper gears geared with both sides of said worm gear; lower gears positioned below said upper gears and geared with said upper gears at inner side; solenoids which force said lower gears to move up-and-down, controlling power transmission between the two gears; and cranks connected to said lower gears and the lower part of said solenoid, wherein said steering bars are eccentrically connected to the circumferences of said cranks, and operate simultaneously to open or close the plates connected to said front axis.

14. The multiple-legged walking apparatus according to claim 13, each distal end of said steering bars far from said driving means is connected to at least one link, and each end of said link, which is not connected to said steering bar, is fixedly installed forming an acute angle with said steering bar, and the connective part between said steering bar and said link is connected to a spring, of which end is fixedly installed, such that said plate automatically return to initial position.

15. A multiple-legged walking apparatus characterized by comprising: front and rear axes driven by receiving power from power source; a plurality of closed multi-articulated link members, which are made of a plurality of links to form quadrilaterals; a plurality of plates connected to both ends of said front and rear axes and connecting said closed multi-articulated link members; and a driving means opening and closing said plates that are connected to both ends of said front axis in cooperation with each steering bars, wherein each upper vertex of said closed multi-articulated link members is eccentrically connected to said axis, and one vertical link of a closed multi- articulated link members is hinged on said plate, an end of said closed multi-articulated link members, which reaches the ground when said front and rear axes rotate, moves forming an oval orbit, a pair of legs installed diagonally opposite each other are positioned with 180° phase difference from another pair of legs, and said driving means steers the body by repetitively performing the activities that said driving means, when link members positioned at opposite side to steering direction reach the ground, forces all of said plates to open toward both ends of said front axis, and when link members positioned at the same side with steering direction reach the ground, forces all of said plates to close.

6. The multiple-legged walking apparatus according to claim 15, said front and rear axes perpendicularly connected to the main axis that is operated by one power source, and are operated in cooperation with a pair of bevel gears.

17. The multiple-legged walking apparatus according to claim 15, further comprises cranks which are circular shape and rotate with an axis, wherein each center of said cranks is fixedly connected to said front and rear axes respectively, and each upper vertex of said closed multi-articulated link members is eccentrically connected to the circumference of the crank.

18. The multiple-legged walking apparatus according to claim 15, the center of gravity of said multiple-legged walking apparatus is formed at the crossing point of the two diagonals of said pair of legs and another pair of legs to safely perform walking motion.

19. The multiple-legged walking apparatus as in any of claims 15-18, said closed multi-articulated link comprises upper and lower horizontal links and front and rear vertical links, wherein one end of said lower horizontal link is expanded to contact the ground.

20. The multiple-legged walking apparatus according to claim 19, the orbit OE of an end of said horizontal or vertical link satisfies OE = ,e ' ⁺ /₅β' ⁺ /_{3 >} wherein θ i is an angle between the horizon and the extended line from the center of said front or rear axis to the upper vertex of said closed multi-articulated link, and li is the length of the expanded line, θ ₃ is the angle between the horizon and each vertical link, 1₅ is the length of the vertical link, θ 5 is the angle between the horizon and each horizontal link, and 1₃ is the length of the lower horizontal link.

21. The multiple-legged walking apparatus as in any of claims 15-18, closed multi- articulated link members comprise upper and lower horizontal links, front and rear vertical links, wherein one end of said front or rear vertical link is expanded to contact the ground.

22. The multiple-legged walking apparatus according to claim 21, the orbit OE of an end of said horizontal or vertical link satisfies OE —

+ ₅g ³ +l_3β ⁵ , wherein θ 1 is an angle between the horizon and the extended line from the center of said front or rear axis to the upper vertex of said closed multi-articulated link, and li is the length of the expanded line, θ ₃ is the angle between the horizon and each vertical link, 1₅ is the length of the vertical link, θ ₅ is the angle between the horizon and each horizontal link, and 1₃ is the length of the lower horizontal link.

23. The multiple-legged walking apparatus according to claim 15, pitching angle θ_y and rolling θ_x satisfy θ_γ ≤ tan^~x (I / h) and θ_x < tan^_1 (δ/Λ) , wherein 1 is the length, h is the height, and b is the width of said multiple-legged walking apparatus.

24. The multiple-legged walking apparatus according to claim 15, said driving means comprises a linear-shape steering piece, and said steering bars are connected at both ends of said steering piece, and another ends of steering bars are connected to the front and lower part of said plates forming an acute angle, and when said steering piece rotates 90°, said steering bars push said plates to both ends of said front axis, and when said steering piece rotates 180°, said steering bars force said plates to return to initial position.

25. The multiple-legged walking apparatus according to claim 15, said driving means comprises a motor; a worm gear connected to said motor; upper gears geared with both ends of said worm gear; lower gears positioned below said upper gears and geared with said upper gears at inner side; solenoids which force said lower gears to move up-and-down, controlling power transmission between the two gears; and cranks connected to said lower gears and the lower part of said solenoids, wherein said steering bars are eccentrically connected to the circumferences of said cranks and simultaneously open or close the plates connected to said front axis.

26. The multiple-legged walking apparatus according to claim 26, each distal end of said steering bars far from said driving means is connected to at least one link, and each end of said link, which is not connected to said steering bar, is fixedly installed forming an acute angle with said steering bar, and the connective part between said steering bar and said link is connected to a spring, of which end is fixedly installed, such that said plate automatically return to initial position.