A leg-foot walking device with variable scaling ratio and a scaling ratio transformation method

Abstract

The present invention discloses a leg-foot walking device with variable scaling ratio and a scaling ratio transformation method, which includes a body assembly and a linkage assembly. The body assembly is used to install a driver and the linkage assembly. The linkage assembly includes a thigh module, a calf module, a long link, a short link, and a non-linear transmission module, wherein the lengths of the thigh module and the calf module can be adjusted according to a certain non-linear proportional relationship, so as to adjust the scaling ratio while ensuring the scaling characteristics. The present invention can achieve the adjustment of the scaling ratio without disassembling and replacing parts of the leg-foot walking device, can improve the energy utilization efficiency, reduce the peak power demand, and is easy to control on the basis of ensuring walking stability.

Description

Technical Field

[0001] The present invention relates to the technical field of walking mechanisms, and particularly relates to a leg-foot walking device with variable scaling ratio and a scaling ratio transformation method. Background Art

[0002] Currently, typical configurations of leg-foot walking devices include open-chain articulated type, Cartesian coordinate type, and closed-chain fixed scaling ratio type. The above-mentioned leg configurations are widely used in leg-foot transportation platforms and leg-foot robots, and play an important role in fields such as disaster relief, mountain transportation, forest fire fighting, and military operations. However, the existing configurations also have problems such as difficult walking control, low energy utilization efficiency, and large peak power demand. Summary of the Invention

[0003] In view of the above problems, the present invention discloses a leg-foot walking device with variable scaling ratio and a scaling ratio transformation method, which can improve the energy utilization efficiency, reduce the peak power demand, and is easy to control on the basis of ensuring stable walking.

[0004] The technical solution of the present invention is as follows:

[0005] A leg-foot walking device with variable scaling ratio, comprising: a body assembly and a link assembly;

[0006] The body assembly includes a frame, a horizontal driver, a vertical driver, a vertical slider, a horizontal slider, a horizontal guide rail, and a vertical guide rail. Both the horizontal driver and the vertical driver are provided with telescopic piston rods.

[0007] The horizontal slider is slidably mounted on the horizontal guide rail. One end of the horizontal slider is connected to the piston rod of the horizontal driver, and the other end is connected to the link assembly.

[0008] The vertical slider is slidably mounted on the vertical guide rail. One end of the vertical slider is connected to the piston rod of the vertical driver, and the other end is connected to the link assembly.

[0009] The link assembly includes a thigh module, a non-linear transmission module, a first-stage transmission belt, a second-stage transmission belt, a calf module, a long link, a horizontal drive shaft, and a short link.

[0010] One end of the thigh module is hinged to the vertical slider, and the other end is hinged to the calf module; there are stepped shafts on both sides of the thigh module, which are respectively hinged to a short link, and a non-linear transmission module is sleeved and partially fixed on the stepped shaft on one side, and the non-linear transmission module is located inside the short link on this side.

[0011] One end of the short link is jointly hinged to the thigh module and the non-linear transmission module, and the other end is hinged to the horizontal drive shaft.

[0012] One end of the long connecting rod is hinged to the calf module, and the other end is hinged to the horizontal drive shaft;

[0013] The horizontal drive shaft passes through the shaft hole in the middle of the horizontal slider, and one end is fixed on the horizontal slider. The long connecting rod, the short connecting rod and the piston rod of the horizontal drive are arranged on the horizontal drive shaft;

[0014] There are stepped shafts on both sides of the calf module, which are respectively hinged to a long connecting rod;

[0015] The first-stage transmission belt is connected between the driving stepped pulley on the non-linear transmission module and the driven stepped pulley on the calf module, and the driven stepped pulley is installed on the calf-thigh connecting shaft;

[0016] The second-stage transmission belt is connected between the driven stepped pulley on the calf module and the pulley;

[0017] Both the thigh module and the calf module itself have two mechanisms that can relatively expand, contract, and rotate;

[0018] On the non-linear transmission module, there are a movable slide plate, rollers, and a synchronous belt. The thigh module drives the slide plate to move, the slide plate drives the rollers to move, the rollers drive the synchronous belt to move, and the synchronous belt drives the driving stepped pulley to move.

[0019] Furthermore:

[0020] The thigh module is divided into the upper thigh rod and the lower thigh rod;

[0021] The stepped shafts on both sides of the upper thigh rod are hinged to the vertical slider;

[0022] One short connecting rod is hinged to each of the stepped shafts on both sides of the lower thigh rod;

[0023] Both the upper thigh rod and the thigh threaded shaft can extend into the lower thigh rod;

[0024] A thigh spline shaft and a thigh threaded shaft are arranged between the upper thigh rod and the lower thigh rod. An adjustment motor is installed at the end of the upper thigh rod, and the output shaft of the motor is connected to the thigh spline shaft. The thigh spline shaft is internally splined with the thigh threaded shaft, and the outside of the thigh threaded shaft is threadedly mated with the upper thigh rod;

[0025] The upper thigh rod is fixed to the slide plate by screws passing through the installation groove on the side of the lower thigh rod.

[0026] Furthermore:

[0027] The thigh threaded shaft is a stepped shaft. Two thigh tapered roller bearings are respectively sleeved on the two journal necks of the thigh threaded shaft, and the shaft collar is clamped between the two thigh tapered roller bearings;

[0028] The thigh bearing seat is inserted into and fixed inside the lower section of the thigh rod, and the end of the thigh bearing seat is connected to the thigh bearing end cover;

[0029] There is a groove in the middle of the thigh bearing seat, and the thigh tapered roller bearing is installed in the groove. The end face of the outer ring of one thigh tapered roller bearing abuts against the bottom surface of the groove of the thigh bearing seat, and the end face of the outer ring of the other thigh tapered roller bearing abuts against the thigh bearing end cover;

[0030] The end faces of the inner rings of the two thigh tapered roller bearings respectively abut against the two shoulders of the thigh threaded shaft.

[0031] Furthermore:

[0032] The non-linear transmission module is provided with a mounting plate, which is fixed to the side surface of the upper section of the thigh rod. There are adjustment slots, transverse chutes, and slide plate guiding slots on the mounting plate;

[0033] A large pulley, pulley fixing block, pulley pressing plate, active stepped pulley, small pulley, roller, and synchronous belt are mounted on the front of the mounting plate, and a slide plate is mounted on the back. The slide plate is clamped between the mounting plate and the lower section of the thigh rod;

[0034] The inner side of the synchronous belt is wound around three large pulleys, two small pulleys, and the active stepped pulley, and the outer side is wound around two rollers, and is clamped between two groups of pulley fixing blocks and pulley pressing plates;

[0035] The slide plate is provided with a small pulley mounting shaft, a pulley fixing block mounting shaft, and a longitudinal chute. The small pulley mounting shaft and the pulley fixing block mounting shaft pass through the transverse chute of the mounting plate and are respectively sleeved with a small pulley and a pulley fixing block;

[0036] The roller shaft passes through the longitudinal chute of the slide plate and the adjustment slot of the mounting plate;

[0037] The slide plate guiding slot is a rectangular slot, which cooperates with the slide plate to limit the position of the slide plate.

[0038] Furthermore:

[0039] There are two slide plates, and they are mirror-image structures. One slide plate is connected to the upper section of the thigh rod by screws and slides in the slide plate guiding slot; the other slide plate is not connected to the upper section of the thigh rod and can slide in the slide plate guiding slot under the drive of the synchronous belt.

[0040] Furthermore:

[0041] The center line of the adjustment slot and the center line of the transverse chute have a non-linear function correspondence relationship. The adjustment slot provides guidance for the roller shaft, so that the roller shaft moves along a curve along the adjustment slot.

[0042] Furthermore:

[0043] The roller shaft is a stepped shaft. One end of the roller shaft is clamped between the sliding plate and the lower part of the thigh rod. A roller is sleeved on the shoulder of the roller shaft and is axially limited by a nut.

[0044] The driving stepped pulley shaft is a stepped shaft. A driving stepped pulley is sleeved on the middle journal and is axially limited by a nut.

[0045] There are three large pulleys, which are distributed at three corners of the rectangular mounting plate.

[0046] The pulley pressing plate is fixed on the pulley fixing block by bolts.

[0047] Furthermore:

[0048] The calf module is divided into an upper calf rod and a lower calf rod.

[0049] One end of the upper calf rod is hinged to the thigh module.

[0050] The long connecting rods are hinged to both sides of the upper calf rod.

[0051] A transmission shaft is installed on the upper calf rod, and a pulley and a driving bevel gear are fixed on the transmission shaft.

[0052] The driving bevel gear meshes with the driven bevel gear. The driven bevel gear is fixed on the bevel gear fixing frame, and the bevel gear fixing frame is connected to one end of the calf spline shaft.

[0053] Both sides of the upper calf rod are connected to the calf bearing seats.

[0054] The inside of the lower calf rod is in spline fit with the calf spline shaft.

[0055] The outside of the lower calf rod is in threaded fit with the calf bearing seats.

[0056] A method for changing the scaling ratio of a leg-foot walking device with variable scaling ratio, characterized in that

[0057] Set the initial conditions as follows:

[0058] The hinge point A is the hinge point between the upper thigh rod and the vertical slider.

[0059] The hinge point B is the hinge point of the long connecting rod, the short connecting rod and the piston rod of the horizontal drive.

[0060] The point C is the foot end at the bottom of the lower calf rod.

[0061] The hinge point D is the hinge point between the lower thigh rod and the short connecting rod.

[0062] The hinge point E is the hinge point between the thigh module and the calf module.

[0063] The hinge point F is the hinge point between the upper calf rod and the long connecting rod.

[0064] Then, AE corresponds to the length of the thigh module, CE corresponds to the length of the calf module, BD corresponds to the length of the short connecting rod, and BF corresponds to the length of the long connecting rod;

[0065] Ensure that BDEF is a parallelogram and A, B, and C are on a straight line, then the proportional scaling characteristics of the thigh and calf exist, and the scaling ratio k is:

[0066]

[0067] Let the length of AD be a and the length of CF be b. Since the lengths of EF and DE are fixed values, the product of the lengths of EF and DE is a constant c, and the product of AD and CF is also a constant c;

[0068] Let the shortest length of AD be a0, the longest be a1, the change in the length of AD be Δa, and the radius of the part of the driving stepped pulley that cooperates with the synchronous belt be R.

[0069] When the following conditions are met:

[0070] (1) When the length of AD increases by Δa from a0, the lower segment of the thigh rod drives the slide plate of the non-linear transmission module to move a distance of Δa on the upper segment of the thigh rod, and the adjusting roller moves along the direction perpendicular to the moving direction of Δa:

[0071]

[0072] (2) The transmission ratio from the driving stepped pulley to the driven bevel gear is:

[0073] (3) The lead of the thread of the lower segment of the calf is: 2πR;

[0074] The adjustment of the scaling ratio can be achieved.

[0075] Compared with the prior art, the beneficial effects of the present invention are reflected in:

[0076] 1. The variable-scaling leg-foot walking device proposed by the present invention separates the horizontal drive and the vertical drive, realizes the motion decoupling of the leg-foot walking system in the sagittal plane, and is easy to achieve walking control;

[0077] 2. The variable-scaling leg-foot walking device proposed by the present invention only requires one adjustment driver, and through the non-linear mechanical transmission mechanism, the lengths of the thigh module and the calf module can be adjusted to realize the adjustment of the scaling ratio of the walking device;

[0078] 3. The variable scaling ratio leg-foot walking device proposed by the present invention can adjust the scaling ratio within a certain range to achieve multi-mode walking motion of the leg-foot robot. It can walk quickly with high leg lifts and large stride lengths under no-load and light-load conditions, and walk steadily with low leg lifts and small stride lengths under heavy-load conditions, improving the overall energy utilization efficiency of the machine and reducing the system peak power. BRIEF DESCRIPTION OF THE DRAWINGS

[0079] Figure 1 is a schematic diagram of the overall structure of the device of the present invention;

[0080] Figure 2 is a schematic diagram of the body assembly structure of the device of the present invention;

[0081] Figure 3 is a schematic diagram of the connecting rod assembly structure of the device of the present invention;

[0082] Figure 4 is an exploded schematic diagram of the thigh module structure of the device of the present invention;

[0083] Figure 5 is a cross-sectional view of the thigh module of the device of the present invention;

[0084] Figure 6 is a schematic diagram of the thigh threaded shaft structure of the device of the present invention;

[0085] Figure 7 is a schematic diagram of the non-linear transmission module structure of the device of the present invention;

[0086] Figure 8 is a front view of the mounting plate structure of the device of the present invention;

[0087] Figure 9 is a rear view of the mounting plate structure of the device of the present invention;

[0088] Figure 10 is a schematic diagram of the skateboard structure of the device of the present invention;

[0089] Figure 11 is a schematic diagram of the roller shaft structure of the device of the present invention;

[0090] Figure 12 is an exploded schematic diagram of the calf module structure of the device of the present invention;

[0091] Figure 13 is a partial exploded schematic diagram of the calf module structure of the device of the present invention;

[0092] Figure 14 is a cross-sectional view of the calf module structure of the device of the present invention;

[0093] Figure 15 is a schematic diagram of the calf bearing seat structure of the device of the present invention;

[0094] Figure 16 It is a schematic diagram of the lower segment structure of the calf rod of the device of the present invention;

[0095] Figure 17 It is a schematic diagram of the principle of the device of the present invention;

[0096] Figure 18 It is a schematic diagram of the rod length adjustment relationship of the device of the present invention;

[0097] Figure 19 It is a schematic diagram of the adjustment dimension of the non-linear transmission module of the device of the present invention;

[0098] Figure 20 It is a schematic diagram of three scaling ratio states of the device of the present invention.

[0099] In the figure:

[0100] 1 - Body assembly; 1.1 - Frame; 1.2 - Horizontal driver; 1.3 - Vertical driver; 1.4 - Vertical slider; 1.5 - Horizontal slider, 1.6 - Horizontal guide rail; 1.7 - Vertical guide rail;

[0101] 2 - Link assembly; 2.1 - Thigh module; 2.2 - Non-linear transmission module; 2.3 - First-stage transmission belt; 2.4 - Second-stage transmission belt; 2.5 - Calf module; 2.6 - Long link; 2.7 - Horizontal drive shaft; 2.8 - Short link;

[0102] 2.1.1 - Adjustment motor; 2.1.2 - Thigh spline shaft; 2.1.3 - Upper segment of thigh rod; 2.1.4 - Thigh threaded shaft; 2.1.5 - Thigh bearing end cover; 2.1.6 - Thigh tapered roller bearing; 2.1.7 - Thigh bearing seat; 2.1.8 - Lower segment of thigh rod;

[0103] 2.2.1 - Mounting plate; 2.2.2 - Large pulley; 2.2.3 - Pulley fixing block; 2.2.4 - Pulley pressing plate; 2.2.5 - Slide plate; 2.2.6 - Active stepped pulley; 2.2.7 - Small pulley; 2.2.8 - Roller shaft; 2.2.9 - Roller; 2.2.10 - Timing belt;

[0104] 2.2.1.1 - Mounting plate fixing hole; 2.2.1.2 - Large pulley mounting shaft; 2.2.1.3 - Adjustment slot; 2.2.1.4 - Transverse chute; 2.2.1.5 - Active stepped pulley shaft; 2.2.1.6 - Positioning shaft hole; 2.2.1.7 - Slide plate guide chute;

[0105] 2.2.5.1 - Longitudinal chute; 2.2.5.2 - Small pulley mounting shaft; 2.2.5.3 - Slide plate fixing hole; 2.2.5.4 - Pulley fixing block mounting shaft;

[0106] 2.5.1 - Upper segment of the calf rod; 2.5.2 - Calf - thigh connecting shaft; 2.5.3 - Driven stepped pulley; 2.5.4 - Sleeve; 2.5.5 - Driving bevel gear; 2.5.6 - Transmission shaft; 2.5.7 - Pulley; 2.5.8 - Driven bevel gear; 2.5.9 - Bevel gear fixing bracket; 2.5.10 - Calf bearing end cover; 2.5.11 - Calf tapered roller bearing; 2.5.12 - Calf spline shaft; 2.5.13 - Calf bearing seat; 2.5.14 - Lower segment of the calf rod. Detailed implementation mode

[0107] To further elaborate on the technical solution of the present invention, it is specifically described as follows in combination with the accompanying drawings of the specification and specific embodiments.

[0108] As Figure 1 shown, the variable - scale leg - foot walking device of the present invention mainly includes two parts: a body assembly 1 and a connecting rod assembly 2.

[0109] As Figure 2 shown, the body assembly 1 mainly consists of a frame 1.1, a horizontal driver 1.2, a vertical driver 1.3, a vertical slider 1.4, a horizontal slider 1.5, a horizontal guide rail 1.6, and a vertical guide rail 1.7.

[0110] The frame 1.1 is the installation carrier for other components of the body assembly 1. The horizontal guide rail 1.6 and the vertical guide rail 1.7 are provided on the frame 1.1. Both the horizontal driver 1.2 and the vertical driver 1.3 are telescopic structures with piston rods. The horizontal driver 1.2 is fixed to the frame 1.1 through a connecting pin, and the piston rod of the horizontal driver 1.2 is parallel to the horizontal guide rail 1.6; the horizontal slider 1.5 is slidably installed on the horizontal guide rail 1.6 of the frame 1.1, and the horizontal drive shaft 2.7 (see Figure 3 ) of the connecting rod assembly 2 passes through the horizontal slider 1.5, connecting the piston rod of the horizontal driver 1.2 and the connecting rod assembly 2 through the horizontal drive shaft 2.7. The vertical driver 1.3 is fixed to the frame 1.1 through a connecting pin, the piston rod of the vertical driver 1.3 is parallel to the vertical guide rail 1.7, and the piston rod of the vertical driver 1.3 is connected to the vertical slider 1.4 through a pin shaft; the vertical slider 1.4 is slidably installed on the vertical guide rail 1.7 of the frame 1.1. There are two pin - shaft holes on the vertical slider 1.4. One pin - shaft hole is connected to the piston rod of the vertical driver 1.3 through a pin shaft, and the other pin - shaft hole is used to connect to the connecting rod assembly 2.

[0111] As Figure 3 shown, the connecting rod assembly 2 mainly consists of a thigh module 2.1, a non - linear transmission module 2.2, a first - stage transmission belt 2.3, a second - stage transmission belt 2.4, a calf module 2.5, a long connecting rod 2.6, a horizontal drive shaft 2.7, and a short connecting rod 2.8.

[0112] One end of the thigh module 2.1 has a stepped shaft and is hinged to the vertical slider 1.4; the other end has a shaft hole and is hinged to the calf module 2.4 through a pin shaft. On both sides of the middle of the thigh module 2.1, there are stepped shafts. The outer ends of the stepped shafts are thin ends, and the thin ends are threaded shafts. The stepped shafts on both sides are respectively hinged to a short connecting rod 2.8, and nuts are installed on the threads of the thin ends of the stepped shafts to limit the axial movement of the short connecting rod 2.8. Moreover, a non-linear transmission module 2.2 is also sleeved on one of the stepped shafts, and the non-linear transmission module 2.2 is located inside the short connecting rod 2.8 on this side and is fixed to the side of the thigh module 2.1 by screws.

[0113] The non-linear transmission module 2.2 is sleeved on one of the stepped shafts in the middle of the thigh module 2.1. The non-linear transmission module 2.2 is located inside the short connecting rod 2.8 on this side, and the non-linear transmission module 2.2 is fixed to the side of the thigh module 2.1 by screws.

[0114] The first-stage transmission belt 2.3 connects the non-linear transmission module 2.2 and the calf module 2.5.

[0115] The second-stage transmission belt 2.4 connects two belt pulleys on the calf module 2.5.

[0116] The shaft hole at the upper end of the calf module 2.5 is hinged to the shaft hole at one end of the thigh module 2.1 through a pin shaft. On both sides of the middle of the calf module 2.5, there are stepped shafts. Similarly, the outer ends of the stepped shafts are thin ends, and the thin ends are threaded shafts. The stepped shafts on both sides are respectively hinged to a long connecting rod 2.6, and nuts are installed on the threads of the thin ends of the stepped shafts to limit the axial movement of the long connecting rod 2.6.

[0117] There are two long connecting rods 2.6, which are respectively arranged on both sides of the calf module 2.5. One end of the long connecting rod 2.6 is hinged to the calf module 2.5, and the other end is hinged to the horizontal drive shaft 2.7.

[0118] The horizontal drive shaft 2.7 passes through the shaft hole in the middle of the horizontal slider 1.5, and one end is fixed to the horizontal slider by bolts. The long connecting rod 2.6, the short connecting rod 2.8, and the piston rod of the horizontal driver 1.2 are sleeved on the horizontal drive shaft 2.7.

[0119] There are two short connecting rods 2.8, which are respectively arranged outside the two long connecting rods 2.6. One end of the short connecting rod 2.8 is hinged to the horizontal drive shaft 2.7, and the other end is hinged to the thigh module 2.1.

[0120] Specifically, as Figure 4 and Figure 5 shown, the thigh module 2.1 is mainly composed of an adjustment motor 2.1.1, a thigh spline shaft 2.1.2, an upper thigh rod 2.1.3, a thigh threaded shaft 2.1.4, a thigh bearing end cover 2.1.5, a thigh tapered roller bearing 2.1.6, a thigh bearing seat 2.1.7, and a lower thigh rod 2.1.8.

[0121] The mounting flange of the adjustment motor 2.1.1 is fixed to the upper section 2.1.3 of the thigh rod by bolts, and the output shaft of the adjustment motor 2.1.1 is connected to the thigh spline shaft 2.1.2 by bolts. The rotation of the output shaft of the adjustment motor 2.1.1 can drive the rotation of the thigh spline shaft 2.1.2.

[0122] The thigh spline shaft 2.1.2 is fixed to the output shaft of the adjustment motor 2.1.1 by bolts. The spline part of the thigh spline shaft 2.1.2 is engaged with the spline groove inside the thigh threaded shaft 2.1.4. The thigh threaded shaft 2.1.4 can slide axially on the spline shaft 2.1.2. The rotation of the thigh spline shaft 2.1.2 can drive the rotation of the thigh threaded shaft 2.1.4.

[0123] The upper section 2.1.3 of the thigh rod has internal threads, stepped shafts on both sides, and threaded holes on one end face. The internal threads of the upper section 2.1.3 of the thigh rod are engaged with the external threads of the thigh threaded shaft 2.1.4. The stepped shafts on both sides of the upper section 2.1.3 of the thigh rod are hinged to the vertical slider 1.4. The threaded holes on the end face of the upper section 2.1.3 of the thigh rod are used to fix the adjustment motor 2.1.1. The upper section 2.1.3 of the thigh rod, the thigh threaded shaft 2.1.4, the thigh bearing end cover 2.1.5, the thigh tapered roller bearing 2.1.6, and the thigh bearing seat 2.1.7 can be inserted into the inside of the lower section 2.1.8 of the thigh rod, where the upper section 2.1.3 of the thigh rod can slide closely along the inner wall of the lower section 2.1.8 of the thigh rod.

[0124] Furthermore, as shown in Figure 6 The thigh threaded shaft 2.1.4 is a stepped shaft with a spline groove inside and threads outside. The shaft shoulder of the thigh threaded shaft 2.1.4 is used for the axial positioning of the thigh tapered roller bearing 2.1.6. The spline groove of the thigh threaded shaft 2.1.4 is engaged with the thigh spline shaft 2.1.2, enabling the thigh threaded shaft 2.1.4 to rotate under the drive of the thigh spline shaft 2.1.2 and also slide axially on the thigh spline shaft 2.1.2. The external threads of the thigh threaded shaft 2.1.4 are engaged with the internal threads of the upper section 2.1.3 of the thigh rod. The rotation of the thigh threaded shaft 2.1.4 can drive the lower section 2.1.8 of the thigh rod to move axially, thereby changing the overall length of the thigh module 2.1.

[0125] The thigh bearing end cover 2.1.5 is fixed to the end face of the thigh bearing seat 2.1.7 by bolts to limit the axial position of the thigh tapered roller bearing 2.1.6.

[0126] There are two thigh tapered roller bearings 2.1.6. The two thigh tapered roller bearings 2.1.6 are respectively sleeved on the two journal necks of the thigh threaded shaft 2.1.4, and the shaft collar is clamped between the two thigh tapered roller bearings 2.1.6. The thigh tapered roller bearings 2.1.6 are installed in the groove of the thigh bearing seat 2.1.7. The end face of the bearing outer ring of one thigh tapered roller bearing 2.1.6 abuts against the bottom surface of the groove of the thigh bearing seat 2.1.7, and the end face of the bearing outer ring of the other thigh tapered roller bearing 2.1.6 abuts against the thigh bearing end cover 2.1.5. The end faces of the bearing inner rings of the two thigh tapered roller bearings 2.1.6 respectively abut against the two shoulders of the thigh threaded shaft 2.1.4.

[0127] The middle circular groove of the thigh bearing seat 2.1.7 is used to install the thigh tapered roller bearing 2.1.6. There are threaded holes on the end face for fixing the thigh bearing end cover 2.1.5. The thigh bearing seat 2.1.7 is inserted inside the lower section 2.1.8 of the thigh rod, and its outer contour closely adheres to the inner wall of the lower section 2.1.8 of the thigh rod. There are threaded holes on the side of the thigh bearing seat 2.1.7 and it is fixed by bolts passing through the lower section 2.1.8 of the thigh rod.

[0128] The shaft hole at one end of the lower section 2.1.8 of the thigh rod is hinged to the calf module 2.5 through a pin shaft. There are stepped shafts on both sides at the other end of the lower section 2.1.8 of the thigh rod. A non-linear transmission module 2.2 is sleeved on one stepped shaft. At the same time, there is a threaded hole on one side of the lower section 2.1.8 of the thigh rod to fix the non-linear transmission module 2.2 with screws. At the same time, there is an installation groove on one side of the lower section 2.1.8 of the thigh rod for connecting the slide plate 2.2.5 on the non-linear transmission module 2.2 (see Figure 7 ). Screws pass through this installation groove to fix the slide plate 2.2.5 to the upper section 2.1.3 of the thigh rod. A short connecting rod 2.8 is hinged to each of the stepped shafts on both sides of the lower section 2.1.8 of the rod. There are threads on the thin end of the stepped shaft for installing nuts to limit the axial position of the short connecting rod 2.8.

[0129] As Figure 7 shown, the non-linear transmission module 2.2 is provided with a mounting plate 2.2.1, a large pulley 2.2.2, a pulley fixing block 2.2.3, a pulley pressing plate 2.2.4, a slide plate 2.2.5, a driving stepped pulley 2.2.6, a small pulley 2.2.7, a roller shaft 2.2.8, rollers 2.2.9 and a synchronous belt 2.2.10.

[0130] As Figure 8 and Figure 9 shown, the mounting plate 2.2.1 has mounting plate fixing holes 2.2.1.1, a large pulley mounting shaft 2.2.1.2, an adjustment slot 2.2.1.3, a transverse chute 2.2.1.4, a driving stepped pulley shaft 2.2.1.5, a positioning shaft hole 2.2.1.6 and a slide plate guiding groove 2.2.1.7 (located on the back of the mounting plate 2.2.1).

[0131] The mounting plate fixing hole 2.2.1.1 is used to fix the mounting plate 2.2.1. The bolt passes through the mounting plate fixing hole 2.2.1.1 and is screwed into the threaded hole on the side of the lower section 2.1.8 of the thigh rod, fixing the mounting plate 2.2.1 on the side of the lower section 2.1.8 of the thigh rod.

[0132] The large pulley mounting shaft 2.2.1.2 is a stepped shaft. The middle journal is used to mount the large pulley 2.2.2. The thin end of the large pulley mounting shaft 2.2.1.2 is a threaded shaft, which is used to mount a nut to limit the axial position of the large pulley 2.2.2. There are three large pulley mounting shafts 2.2.1.2, which are distributed at the three corners of the rectangular mounting plate 2.2.1.

[0133] The center line of the adjustment slot 2.2.1.3 and the center line of the transverse sliding slot 2.2.1.4 have a non - linear function correspondence. The adjustment slot 2.2.1.3 is used to provide guidance for the roller shaft 2.2.8, enabling the roller shaft 2.2.8 to move along the adjustment slot 2.2.1.3 in a curve, thereby realizing non - linear transmission. There are two upper and lower adjustment slots 2.2.1.3, which are provided for the two roller shafts 2.2.8 to use.

[0134] The transverse sliding slot 2.2.1.4 is used to provide guidance for the sliding plate 2.2.5.

[0135] The driving stepped pulley shaft 2.2.1.5 is a stepped shaft. The middle journal is used to mount the driving stepped pulley 2.2.6. The thin end of the driving stepped pulley shaft 2.2.1.5 is a threaded shaft, which is used to mount a nut to limit the axial position of the driving stepped pulley 2.2.6.

[0136] The positioning shaft hole 2.2.1.6 is sleeved on the stepped shaft on one side of the lower section 2.1.8 of the thigh rod.

[0137] The sliding plate guiding slot 2.2.1.7 is a rectangular slot, which cooperates with the sliding plate 2.2.5 to limit the position of the sliding plate 2.2.5.

[0138] The large pulley 2.2.2 is sleeved on the journal of the large pulley mounting shaft 2.2.1.2 and is axially fixed by a shaft shoulder and a nut.

[0139] The pulley fixing block 2.2.3 is sleeved on the pulley fixing block mounting shaft 2.2.5.4 of the sliding plate 2.2.5 ( Figure 10 as shown), and is axially fixed by a shaft shoulder and a nut.

[0140] The pulley pressing plate 2.2.4 is fixed on the pulley fixing block 2.2.3 by bolts, pressing the synchronous belt 2.2.10 between the pulley pressing plate 2.2.4 and the pulley fixing block 2.2.3.

[0141] As Figure 10As shown, the skateboard 2.2.5 has a longitudinal chute 2.2.5.1, a small pulley mounting shaft 2.2.5.2, a skateboard fixing hole 2.2.5.3, and a pulley fixing block mounting shaft 2.2.5.4. The longitudinal chute 2.2.5.1 cooperates with the roller shaft 2.2.8 to position and guide the roller shaft 2.2.8. A small pulley 2.2.7 is sleeved on the journal part of the small pulley mounting shaft 2.2.5.2, and the thin end of the small pulley mounting shaft 2.2.5.2 has a thread for installing a nut to limit the axial movement of the small pulley 2.2.7. The skateboard fixing hole 2.2.5.3 cooperates with a screw to fix the skateboard 2.2.5 to the upper part of the thigh rod 2.1.3, so that the skateboard 2.2.5 moves together with the upper part of the thigh rod 2.1.3. A rectangular part of the pulley fixing block mounting shaft 2.2.5.4 is sleeved with a pulley fixing block 2.2.3, and the thin end of the pulley fixing block mounting shaft 2.2.5.4 has a thread for installing a nut to limit the axial movement of the pulley fixing block 2.2.3.

[0142] The skateboard 2.2.5 is attached inside the skateboard guiding chute 2.2.1.7. The small pulley mounting shaft 2.2.5.2 and the pulley fixing block mounting shaft 2.2.5.4 of the skateboard 2.2.5 pass through the transverse chute 2.2.1.4 of the mounting plate 2.2.1, and the skateboard 2.2.5 is clamped between the mounting plate 2.2.1 and the lower part of the thigh rod 2.1.8. There are two skateboards 2.2.5, which are mirror-image structures of each other, and a small pulley 2.2.7 and a pulley fixing block 2.2.3 are sleeved on the skateboard 2.2.5. As Figure 10 shown, one skateboard 2.2.5 is connected to the upper part of the thigh rod 2.1.3 by a screw and slides inside the skateboard guiding chute 2.2.1.7 (such as Figure 7 the lower skateboard 2.2.5 in the structural schematic diagram of the non-linear transmission module 2.2 shown); the other skateboard 2.2.5 with a mirror-image structure is floating, not connected to the upper part of the thigh rod 2.1.3, and can slide inside the skateboard guiding chute 2.2.1.7 driven by the synchronous belt 2.2.10 (such as Figure 7 the upper skateboard 2.2.5 in the structural schematic diagram of the non-linear transmission module 2.2 shown).

[0143] The driving stepped pulley 2.2.6 is sleeved on the driving stepped pulley shaft 2.2.1.5 of the mounting plate 2.2.1 and is axially fixed by a shaft shoulder and a nut. The radius of the driving stepped pulley 2.2.6 that cooperates with the synchronous belt 2.2.10 is larger, and the radius that cooperates with the first-stage transmission belt 2.3 is smaller.

[0144] There are two small pulleys 2.2.7, which are respectively sleeved on the small pulley mounting shafts 2.2.5.2 of the two skateboards 2.2.5 and are axially fixed by a shaft shoulder and a nut.

[0145] As Figure 11As shown, the roller shaft 2.2.8 is a stepped shaft. The roller shaft 2.2.8 passes through the longitudinal chute 2.2.5.1 of the sliding plate 2.2.5 and the adjustment slot 2.2.1.3 of the mounting plate. One end of the roller shaft 2.2.8 is clamped between the sliding plate 2.2.5 and the lower section 2.1.8 of the thigh rod. A roller 2.2.9 is sleeved on the journal of the roller shaft 2.2.8. The thin end of the roller shaft 2.2.8 has a thread for installing a nut to limit the axial movement of the roller 2.2.9.

[0146] The roller 2.2.9 is sleeved on the journal of the roller shaft 2.2.8 and is axially fixed by a shaft shoulder and a nut.

[0147] The inner side of the synchronous belt 2.2.10 is wound around three large belt pulleys 2.2.2, two small belt pulleys 2.2.7 and the active stepped belt pulley 2.2.6. The outer side of the synchronous belt 2.2.10 is wound around two roller shafts 2.2.8, and the synchronous belt 2.2.10 is clamped between two groups of belt pulley fixing blocks 2.2.3 and the belt pulley pressing plate 2.2.4.

[0148] The sliding plate 2.2.5 moves relative to the lower section 2.1.8 of the thigh rod along with the upper section 2.1.3 of the thigh rod. The belt pulley fixing blocks 2.2.3 and the belt pulley pressing plate 2.2.4 clamp the synchronous belt 2.2.10 and move together with the sliding plate 2.2.5. The synchronous belt 2.2.10 drives the active stepped belt pulley 2.2.6 to rotate.

[0149] As shown in Figure 12 、 13 and 14, the calf module 2.5 is composed of the upper section 2.5.1 of the calf rod, the calf-thigh connecting shaft 2.5.2, the driven stepped belt pulley 2.5.3, the sleeve 2.5.4, the active bevel gear 2.5.5, the transmission shaft 2.5.6, the belt pulley 2.5.7, the driven bevel gear 2.5.8, the bevel gear fixing bracket 2.5.9, the calf bearing end cover 2.5.10, the calf tapered roller bearing 2.5.11, the calf spline shaft 2.5.12, the calf bearing seat 2.5.13 and the lower section 2.5.14 of the calf rod.

[0150] The shaft hole at one end of the upper section 2.5.1 of the calf rod is hinged to the thigh module 2.1 through the calf-thigh connecting shaft 2.5.2. There are stepped shafts on both sides in the middle of the upper section 2.5.1 of the calf rod. The journal of the stepped shafts on both sides of the upper section 2.5.1 of the calf rod is used to sleeve the long connecting rod 2.6, and the thin ends of the stepped shafts on both sides of the upper section 2.5.1 of the calf rod have threads for installing nuts to limit the axial position of the long connecting rod 2.6. The shaft hole in the middle of the upper section 2.5.1 of the calf rod is used to install the transmission shaft 2.5.6. Both sides of the upper section 2.5.1 of the calf rod are connected to the calf bearing seat 2.5.13 by bolts.

[0151] The calf-thigh connecting shaft 2.5.2 is a stepped shaft that passes through the shaft hole at one end of the upper section 2.5.1 of the calf rod. One end of the calf-thigh connecting shaft 2.5.2 is fixed to the upper section 2.5.1 of the calf rod by bolts, and the other end is sleeved with a driven stepped pulley 2.5.3. There is a thread on the thin end of the calf-thigh connecting shaft 2.5.2 for installing a nut to limit the axial position of the driven stepped pulley 2.5.3.

[0152] The driven stepped pulley 2.5.3 is sleeved on the calf-thigh connecting shaft 2.5.2 and is fixed axially by a shaft shoulder and a nut. The first-stage transmission belt 2.3 is connected between the driving stepped pulley 2.2.6 and the driven stepped pulley 2.5.3.

[0153] The sleeve 2.5.4 is sleeved on the transmission shaft 2.5.6 between the driving bevel gear 2.5.5 and the upper section 2.5.1 of the calf rod for axially positioning the driving bevel gear 2.5.5.

[0154] The driving bevel gear 2.5.5 is fixed on the transmission shaft 2.5.6 and is fixed circumferentially and axially to the transmission shaft 2.5.6 by key connections and a shaft shoulder and the sleeve 2.5.4 respectively.

[0155] The transmission shaft 2.5.6 is inserted into the shaft hole in the middle of the upper section 2.5.1 of the calf rod and is fixed axially at one end by a circlip and at the other end by a nut. A pulley 2.5.7 and a driving bevel gear 2.5.5 are fixed on the transmission shaft 2.5.6.

[0156] The pulley 2.5.7 is fixed on the transmission shaft 2.5.6 and is fixed circumferentially and axially to the transmission shaft 2.5.6 by key connections and a shaft shoulder and a nut respectively. The second-stage transmission belt 2.4 is connected between the driven stepped pulley 2.5.3 and the pulley 2.5.7.

[0157] The driven bevel gear 2.5.8 is fixed on the bevel gear fixing bracket 2.5.9 and is fixed circumferentially and axially to the bevel gear fixing bracket 2.5.9 by key connections and a shaft shoulder and a nut respectively.

[0158] The bevel gear fixing bracket 2.5.9 is fixed to the end face of the calf spline shaft 2.5.12 by bolts.

[0159] The calf bearing end cover 2.5.10 is fixed to the end face of the calf bearing housing 2.5.13 by bolts to limit the axial position of the calf tapered roller bearing 2.5.11.

[0160] There are two calf tapered roller bearings 2.5.11, which are respectively located on both sides of the collar of the calf spline shaft 2.5.12. The calf tapered roller bearings 2.5.11 are installed in the grooves of the calf bearing housing 2.5.13. The outer rings of the calf tapered roller bearings 2.5.11 are closely attached to the inner walls of the grooves of the calf bearing housing 2.5.13. The end face of the outer ring of one calf tapered roller bearing 2.5.11 abuts against the bottom surface of the groove of the calf bearing housing 2.5.13, and the end face of the outer ring of the other tapered roller bearing 2.5.11 abuts against the bearing end cover 2.5.10.

[0161] The collar of the calf spline shaft 2.5.12 is clamped between the two calf tapered roller bearings 2.5.11. The end face of the smooth shaft side of the calf spline shaft 2.5.12 is connected to the bevel gear fixing bracket 2.5.9. The splines on the calf spline shaft 2.5.12 cooperate with the spline grooves inside the lower part of the calf rod 2.5.14. The calf spline shaft 2.5.12 can not only drive the lower part of the calf rod 2.5.14 to rotate, but also axially slide between the calf spline shaft 2.5.12 and the lower part of the calf rod 2.5.14.

[0162] As Figure 15 shown, the upper part inside the calf bearing housing 2.5.13 is a groove for installing the calf tapered roller bearings 2.5.11. The lower part inside the calf bearing housing 2.5.13 is an internal thread, which cooperates with the external thread of the lower part of the calf rod 2.5.14. There are threaded holes on the outer side surface of the calf bearing housing 2.5.13 for connecting the calf bearing housing 2.5.13 and the upper part of the calf rod 2.5.1. The calf bearing housing 2.5.13 is inserted inside the upper part of the calf rod 2.5.1. The outer wall of the calf bearing housing 2.5.13 is closely attached to the inner wall of the upper part of the calf rod 2.5.1 and is connected to the upper part of the calf rod 2.5.1 through bolts.

[0163] As Figure 16 shown, there are spline grooves inside the lower part of the calf rod 2.5.14, which cooperate with the splines of the calf spline shaft 2.5.12. The lower part of the calf rod 2.5.14 is driven by the calf spline shaft 2.5.12 to rotate. There is an external thread on the outside of the lower part of the calf rod 2.5.14, which cooperates with the internal thread inside the calf bearing housing 2.5.13. When the lower part of the calf rod 2.5.14 rotates, the axial position between the lower part of the calf rod 2.5.14 and the calf bearing housing 2.5.13 changes, thereby changing the overall length of the calf module 2.5.

[0164] Adjust the rotation of the motor 2.1.1 to drive the thigh spline shaft 2.1.2 to rotate. The thigh spline shaft 2.1.2 drives the thigh threaded shaft 2.1.4 to rotate. The thigh threaded shaft 2.1.4 and the lower part of the thigh rod 2.1.8 are connected by threads. The rotation of the thigh threaded shaft 2.1.4 drives the lower part of the thigh rod 2.1.8 to move axially relative to the upper part of the thigh rod 2.1.3, thereby changing the length of the thigh module 2.1.

[0165] Taking the increase in the length of the thigh module 2.1 as an example, the mounting plate 2.2.1 of the non-linear transmission module 2.2 is fixed on the lower segment 2.1.8 of the thigh rod and moves axially together with the lower segment 2.1.8 of the thigh rod. When the mounting plate 2.2.1 moves with the lower segment 2.1.8 of the thigh rod, the slide plate 2.2.5 fixedly connected to the upper segment 2.1.3 of the thigh rod slides in the slide plate guide groove 2.2.1.7 on the mounting plate 2.2.1. The small pulley mounting shaft 2.2.5.2 and the pulley fixing block mounting shaft 2.2.5.4 slide in the transverse chute 2.2.1.4. The roller shaft 2.2.8 slides in the adjustment groove 2.2.1.3 and the longitudinal chute 2.2.5.1. The roller 2.2.9 and the roller shaft 2.2.8 move a certain distance in a direction perpendicular to the axial direction under the limitation of the adjustment groove 2.2.1.3 and the longitudinal chute 2.2.5.1. The slide plate 2.2.5 fixedly connected to the upper segment 2.1.3 of the thigh rod moves away from the driving stepped pulley 2.2.6. The synchronous belt 2.2.10 is fixedly connected to both slide plates 2.2.5. The synchronous belt 2.2.10 drives the other floating slide plate 2.2.5 to move towards the driving stepped pulley 2.2.6.

[0166] The synchronous belt 2.2.10 drives the driving stepped pulley 2.2.6 to rotate. The first-stage transmission belt 2.3 transmits the rotation of the driving stepped pulley 2.2.6 to the driven stepped pulley 2.5.3. The second-stage transmission belt 2.4 transmits the rotation of the driven stepped pulley 2.5.3 to the pulley 2.5.7. The pulley 2.5.7 drives the transmission shaft 2.5.6 to rotate. The transmission shaft 2.5.6 drives the driving bevel gear 2.5.5 to rotate. The driving bevel gear 2.5.5 drives the driven bevel gear 2.5.8 to rotate. The driven bevel gear 2.5.8 drives the bevel gear fixing bracket 2.5.9 to rotate. The bevel gear fixing bracket 2.5.9 drives the lower leg spline shaft 2.5.12 to rotate. The lower leg spline shaft 2.5.12 drives the lower segment 2.5.14 of the lower leg rod to rotate. The lower segment 2.5.14 of the lower leg rod and the upper segment 2.5.1 of the lower leg rod are connected by a thread pair. By rotating the lower segment 2.5.14 of the lower leg rod, the length of the lower leg module 2.5 is reduced, and the lengths of the thigh module 2.1 and the lower leg module 2.5 are always inversely proportional.

[0167] As Figures 17 - 19 shown, the design principle is analyzed, and the initial conditions are set as follows:

[0168] Rod AE corresponds to the thigh module 2.1, rod CE corresponds to the lower leg module 2.5, rod BD corresponds to the short connecting rod 2.8, rod BF corresponds to the long connecting rod 2.6, hinge point E corresponds to the hinge point of the thigh module 2.1 and the lower leg module 2.5, and hinge point F corresponds to the hinge point where the stepped shafts on both sides of the upper segment 2.5.1 of the lower leg rod are hinged to the long connecting rod 2.6.

[0169] Hinge point A is the hinge point between the upper segment 2.1.3 of the thigh rod and the vertical slider 1.4;

[0170] The hinge point B is the hinge point of the long connecting rod 2.6, the short connecting rod 2.8 and the piston rod of the horizontal actuator 1.2;

[0171] The point C is the foot end at the bottom of the lower segment 2.5.14 of the calf rod;

[0172] The hinge point D is the hinge point of the lower segment 2.1.8 of the thigh rod and the short connecting rod 2.8;

[0173] The hinge point E is the hinge point of the thigh module 2.1 and the calf module 2.5;

[0174] The hinge point F is the hinge point of the upper segment 2.1.3 of the calf rod and the long connecting rod 2.6;

[0175] Then, AE corresponds to the length of the thigh module 2.1, CE corresponds to the length of the calf module 2.5, BD corresponds to the length of the short connecting rod 2.8, and BF corresponds to the length of the long connecting rod 2.6.

[0176] Ensure that BDEF is a parallelogram and A, B, and C are on the same line. Then, the proportional scaling characteristic of the thigh and calf exists, and the ratio of the moving distance of the foot end to the moving distance of the actuator is the scaling ratio k, which is:

[0177]

[0178] Let the length of AD be a and the length of CF be b. Since the lengths of EF and DE are fixed values, the product of the lengths of EF and DE is a constant c, and the product of AD and CF is also the constant c.

[0179] Let the shortest length of AD be a0, and at this time, the corresponding length of CF is The longest length of AD is a1, and at this time, the corresponding length of CF is

[0180] Let the change in the length of AD be Δa,

[0181] The radius of the part where the driving stepped pulley 2.2.6 cooperates with the synchronous belt 2.2.10 is R,

[0182] When the following conditions are met:

[0183] (1) When the length of AD increases by Δa, the lower segment 2.1.8 of the thigh rod drives the slide plate 2.2.5 of the non-linear transmission module 2.2 to move a distance Δa on the upper segment 2.1.3 of the thigh rod, and the roller 2.2.9 moves in a direction perpendicular to the moving direction of Δa:

[0184] (2) The transmission ratio from the driving stepped pulley 2.2.6 to the driven bevel gear 2.5.8 is:

[0185] (3) The lead of the thread on the lower segment 2.5.14 of the lower leg rod is: 2πR;

[0186] On the basis of maintaining the scaling characteristics, by adjusting the lengths of AD and CF and ensuring that points A, B, and C are collinear, the scaling ratio k can be adjusted.

[0187] The proof process is as follows:

[0188] The scaled leg configuration has the characteristic of motion decoupling. The principle of motion decoupling of the scaled leg configuration is as follows. In the XY coordinate system, the quadrilateral BDEF is a parallelogram, and point C is on the extension line of the connection between A and B. Geometrically, it is expressed as:

[0189]

[0190] where k is the scaling ratio, that is, the ratio of the motion distance of the foot end to the motion distance of the actuator.

[0191] When the vertical actuator 1.3 drives the hinge point A to move along the Y direction, point C only moves along the Y direction. The motion distance of point C is proportional to the motion distance of point A. When the vertical actuator 1.3 drives A to move a distance y along the Y axis, the foot end point C moves a distance ky in the opposite direction along the Y axis;

[0192]

[0193] When the horizontal actuator 1.2 drives the joint B to move along the X direction, point C only moves along the X axis. The motion distance is proportional to the motion distance of point B. When the horizontal actuator 1.2 drives B to move a distance x along the X axis, the foot end point C moves a distance (k + 1)x in the same direction along the X axis.

[0194]

[0195] According to the proportional relationship of the scaled leg configuration, by adjusting the lengths of AD and CF and ensuring that points A, B, and C are collinear, the scaling ratio k can be adjusted to ensure the proportional scaling characteristics of the scaled leg.

[0196] When the length of AD increases by Δa from a0 and the length of CF decreases by Δb, Δb is:

[0197]

[0198] Draw a straight line L through points (a0, b0) and (a1, b1). The expression is:

[0199]

[0200] The length of Δb′ is:

[0201]

[0202] The length of Δb″ is:

[0203]

[0204] When the length of AD increases by Δa from a0, the length of CF decreases by Δb = Δb′ + Δb″.

[0205] Let

[0206] When the slide plate 2.2.5 fixed to the upper section 2.1.3 of the thigh rod moves a distance of Δa driven by the upper section 2.1.3 of the thigh rod, the adjusting roller shaft 2.2.8 moves in a direction perpendicular to the moving direction of Δa under the restriction of the adjusting slot 2.2.1.3 and the longitudinal sliding slot 2.2.5.1. The arc length l that the synchronous belt 2.2.10 travels on the driving stepped pulley 2.2.6 is:

[0207]

[0208] Let the pulley radius of the driving stepped pulley 2.2.6 that mates with the synchronous belt 2.2.10 be R, then the angular displacement θ1 of the driving stepped pulley 2.2.6 is:

[0209]

[0210] Let the transmission ratio between the driving stepped pulley 2.2.6 and the driven stepped pulley 2.5.3 be i1, the transmission ratio between the driven stepped pulley 2.5.3 and the pulley 2.5.7 be i2, the angular velocity of the pulley 2.5.7 is the same as that of the driving bevel gear 2.5.5, that is, the transmission ratio is 1, and the transmission ratio between the driving bevel gear 2.5.5 and the driven bevel gear 2.5.8 is i3. The transmission ratio i from the driving stepped pulley 2.2.6 to the driven bevel gear 2.5.8 is:

[0211] i = i1i2i3

[0212] Then the angular displacement θ2 of the driven bevel gear 2.5.8 is:

[0213]

[0214] The driven bevel gear 2.5.8, the bevel gear fixing bracket 2.5.9 and the lower leg spline shaft 2.5.12 are fixedly connected. The angular displacement of the lower leg spline shaft 2.5.12 is the same as that of the driven bevel gear 2.5.8. The spline of the lower leg spline shaft 2.5.12 mates with the spline groove inside the lower section 2.5.14 of the lower leg rod. The angular displacement of the lower section 2.5.14 of the lower leg rod is the same as that of the lower leg spline shaft 2.5.12, that is, the angular displacement of the lower section 2.5.14 of the lower leg rod is also θ2. The thread lead of the lower section 2.5.14 of the lower leg rod is s, then the distance that the lower section 2.5.14 of the lower leg rod moves axially is:

[0215]

[0216] When the transmission ratio of the driving stepped pulley to the driven bevel gear When the lead s = 2πR of the lower segment 2.5.14 of the calf rod

[0217]

[0218] That is, when the length of AD increases by Δa from a0, the length of CF decreases by Δb, and the scaling characteristic remains unchanged. The scaling ratio k changes from decreases to

[0219] Figure 20 These are schematic diagrams of three scaling ratio states of the device. From left to right, they are schematic diagrams of the states where the scaling ratios of the traveling device are equal to 3, 2.4, and 2 respectively.

Claims

1. A leg-foot walking device with variable scaling ratio, characterized in that, Comprising: A body assembly and a connecting rod assembly; The body assembly includes a frame, a horizontal drive, a vertical drive, a vertical slider, a horizontal slider, a horizontal guide rail, and a vertical guide rail. Both the horizontal drive and the vertical drive are equipped with telescopic piston rods. The horizontal slider is slidably mounted on the horizontal guide rail. One end of the horizontal slider is connected to the piston rod of the horizontal drive, and the other end is connected to the connecting rod assembly. The vertical slider is slidably mounted on the vertical guide rail. One end of the vertical slider is connected to the piston rod of the vertical drive, and the other end is connected to the connecting rod assembly. The connecting rod assembly includes a thigh module, a non-linear transmission module, a first-stage transmission belt, a second-stage transmission belt, a calf module, a long connecting rod, a horizontal drive shaft, and a short connecting rod. One end of the thigh module is hinged to the vertical slider, and the other end is hinged to the calf module. There are stepped shafts on both sides of the thigh module, which are respectively hinged to a short connecting rod, and a non-linear transmission module is sleeved and partially fixed on the stepped shaft on one side. The non-linear transmission module is located inside the short connecting rod on this side. One end of the short connecting rod is jointly hinged to the thigh module and the non-linear transmission module, and the other end is hinged to the horizontal drive shaft. One end of the long connecting rod is hinged to the calf module, and the other end is hinged to the horizontal drive shaft. The horizontal drive shaft passes through the shaft hole in the middle of the horizontal slider, and one end is fixed on the horizontal slider. The long connecting rod, the short connecting rod, and the piston rod of the horizontal drive are arranged on the horizontal drive shaft. There are stepped shafts on both sides of the calf module, which are respectively hinged to a long connecting rod. The first-stage transmission belt is connected between the driving stepped pulley on the non-linear transmission module and the driven stepped pulley on the calf module. The driven stepped pulley is installed on the calf-thigh connecting shaft. The second-stage transmission belt is connected between the driven stepped pulley on the calf module and the pulley. Both the thigh module and the calf module itself have two mechanisms that can relatively expand, contract, and rotate. The non-linear transmission module is provided with a movable slide plate, rollers, and a synchronous belt. The thigh module drives the slide plate to move, the slide plate drives the rollers to move, the rollers drive the synchronous belt to move, and the synchronous belt drives the driving stepped pulley to move.

2. The variable scaling ratio leg-foot walking device according to claim 1, wherein The thigh module is divided into an upper thigh rod and a lower thigh rod; The stepped shafts on both sides of the upper thigh rod are hinged to the vertical slider; One short connecting rod is hinged to each of the stepped shafts on both sides of the lower thigh rod; Both the upper thigh rod and the thigh threaded shaft can extend into the lower thigh rod; A thigh spline shaft and a thigh threaded shaft are arranged between the upper thigh rod and the lower thigh rod. An adjustment motor is installed at the end of the upper thigh rod, and the output shaft of the motor is connected to the thigh spline shaft. The thigh spline shaft is in internal spline fit with the thigh threaded shaft, and the outside of the thigh threaded shaft is in threaded fit with the upper thigh rod; The upper thigh rod is fixed to the slide plate by screws passing through the installation groove on the side of the lower thigh rod.

3. The variable scaling ratio leg-foot walking device according to claim 2, wherein The thigh threaded shaft is a stepped shaft. Two thigh tapered roller bearings are respectively sleeved on the two journal shafts of the thigh threaded shaft, and the shaft collar is clamped between the two thigh tapered roller bearings. The thigh bearing seat is inserted into and fixed inside the lower section of the thigh rod, and the end of the thigh bearing seat is connected to the thigh bearing end cover; There is a groove in the middle of the thigh bearing seat, and the thigh tapered roller bearing is installed in the groove. The end face of the outer ring of one thigh tapered roller bearing abuts against the bottom surface of the groove of the thigh bearing seat, and the end face of the outer ring of the other thigh tapered roller bearing abuts against the thigh bearing end cover; The end faces of the inner rings of the two thigh tapered roller bearings respectively abut against the two shoulders of the thigh threaded shaft.

4. The variable scaling ratio leg-foot walking device according to claim 1, characterized in that The non-linear transmission module is provided with a mounting plate, which is fixed to the side of the upper section of the thigh rod. There are adjustment slots, transverse chutes, and slide plate guide slots on the mounting plate; On the front of the mounting plate, a large pulley, pulley fixing block, pulley pressing plate, active stepped pulley, small pulley, roller, and synchronous belt are installed. On the back, a slide plate is installed, and the slide plate is clamped between the mounting plate and the lower section of the thigh rod; The inner side of the synchronous belt is wound around three large pulleys, two small pulleys, and the active stepped pulley, and the outer side is wound around two rollers, and is clamped between two groups of pulley fixing blocks and pulley pressing plates; The slide plate is provided with a small pulley mounting shaft, a pulley fixing block mounting shaft, and a longitudinal chute. The small pulley mounting shaft and the pulley fixing block mounting shaft pass through the transverse chute of the mounting plate and are respectively sleeved with a small pulley and a pulley fixing block; The roller shaft passes through the longitudinal chute of the slide plate and the adjustment slot of the mounting plate; The slide plate guide slot is a rectangular slot, which cooperates with the slide plate to limit the position of the slide plate.

5. The variable scaling ratio leg-foot walking device according to claim 4, characterized in that There are two slide plates, which are mirror-image structures of each other. One slide plate is connected to the upper section of the thigh rod by screws and slides in the slide plate guide slot; the other slide plate is not connected to the upper section of the thigh rod and can slide in the slide plate guide slot under the drive of the synchronous belt.

6. The variable scaling ratio leg-foot walking device according to claim 4, characterized in that: The center line of the adjustment slot and the center line of the transverse chute have a non-linear function correspondence relationship. The adjustment slot provides guidance for the roller shaft, so that the roller shaft moves along a curve in the adjustment slot.

7. The variable scaling ratio leg-foot walking device according to claim 4, characterized in that The roller shaft is a stepped shaft. One end of the roller shaft is clamped between the slide plate and the lower section of the thigh rod. A roller is sleeved on the shoulder of the roller shaft and is axially limited by a nut; The active stepped pulley shaft is a stepped shaft. The active stepped pulley is sleeved on the middle journal, and is axially limited by a nut; There are three large pulleys, which are distributed at the three corners of the rectangular mounting plate; The pulley pressing plate is fixed to the pulley fixing block by bolts.

8. The variable scaling ratio leg-foot walking device according to claim 1, characterized in that The calf module is divided into an upper section of the calf rod and a lower section of the calf rod, One end of the upper section of the calf rod is hinged to the thigh module, The long connecting rods are hinged to both sides of the upper section of the calf rod, A transmission shaft is installed on the upper section of the calf rod, and a pulley and an active bevel gear are fixed on the transmission shaft, The driving bevel gear meshes with the driven bevel gear. The driven bevel gear is fixed on the bevel gear fixing bracket, and the bevel gear fixing bracket is connected to one end of the calf spline shaft. Both sides of the upper section of the calf rod are connected with calf bearing seats. The inner part of the lower section of the calf rod is in spline fit with the calf spline shaft. The outer part of the lower section of the calf rod is in threaded fit with the calf bearing seat.

9. The scaling ratio transformation method of the leg-foot walking device with variable scaling ratio according to any one of claims 1-8, characterized in that Set the initial conditions as follows: The hinge point A is the hinge point between the upper section of the thigh rod and the vertical slider. The hinge point B is the hinge point among the long connecting rod, the short connecting rod and the piston rod of the horizontal driver. The point C is the foot end at the bottom of the lower section of the calf rod. The hinge point D is the hinge point between the lower section of the thigh rod and the short connecting rod. The hinge point E is the hinge point between the thigh module and the calf module. The hinge point F is the hinge point between the upper section of the calf rod and the long connecting rod. Then, AE corresponds to the length of the thigh module, CE corresponds to the length of the calf module, BD corresponds to the length of the short connecting rod, and BF corresponds to the length of the long connecting rod. Ensure that BDEF is a parallelogram and A, B, and C are on the same line, then the proportional scaling characteristics of the thigh and calf exist, and the scaling ratio k is: Let the length of AD be a and the length of CF be b. Since the lengths of EF and DE are fixed values, the product of the lengths of EF and DE is a constant c, and the product of AD and CF is also a constant c. Let the shortest length of AD be a0, the longest be a1, the change in the length of AD be Δa, and the radius of the part where the driving stepped pulley cooperates with the synchronous belt be R. When the following conditions are met: (1) When the length of AD increases by Δa from a0, the lower section of the thigh rod drives the slide plate of the non-linear transmission module to move a distance Δa on the upper section of the thigh rod, and adjusts the roller to move in a direction perpendicular to the direction of Δa movement. (2) The transmission ratio of the driving stepped pulley to the driven bevel gear is: (3) The thread lead of the lower calf is: 2πR. The scaling ratio adjustment can be achieved.

Images