Elastic joint and passive power ramp walker science popularization teaching aid and walking method

Abstract

The invention discloses a science popularization teaching aid for an elastic joint and passive power ramp walker and a walking method, and the teaching aid is characterized in that the walker is composed of a simulated body skeleton, four legs and four joints, and the body skeleton is provided with four joint interfaces; the upper end of the simulation leg is provided with a joint interface; the joints are right-angle components made of elastic materials, rectangular cavities in one ends of the joints are connected with rectangular joint connectors of the body framework in an inserted mode, rectangular cavities in the other ends of the joints are connected with rectangular joint connectors of the legs in an inserted mode, and the other three simulation joints are connected with the body framework and the legs in an inserted mode in the same way. The four-footed ramp walker forms an elastic joint and can passively walk to go downhill. Compared with the prior art, the structure is simple, all the assemblies are designed in a plug-in mode, elastic materials are introduced, feasibility of stable walking under a non-hinge structure is achieved, the device serves as an innovative teaching aid to be applied to science popularization display of mechanics-materials science and teenager department and wound exploration, and the device has a good educational demonstration effect.

Description

Technical Field

[0001] The invention relates to the technical field of science popularization teaching aids for walkers, in particular to a science popularization teaching aid for a simple four-legged ramp walker capable of passively walking downhill and a walking method thereof. Background Art

[0002] A passive powered ramp walker is a robot that walks on a slope relying solely on its own gravity. The study of the periodicity and stability of this type of robot's walking is of great significance, as it can help us understand the walking pattern of quadrupeds and how to walk more efficiently. Existing studies have mainly designed ramp walkers with hinged joints, and analyzed the existence of limit cycles by drawing phase diagrams, and then studied its periodicity and stability. However, although existing studies have made in-depth studies on hinged joints and active power feed-in conditions, there is still a lack of research on the feasibility of walking with elastic joints and simpler models. Due to the nature of the elastic joints themselves, there is a process of converting gravitational potential energy into elastic potential energy for storage and release during the walker's downhill process, which will affect the motion state of the robot. Summary of the invention

[0003] The purpose of the invention is to design a popular science teaching aid and walking method of a ramp walker with elastic joints and passive power in view of the deficiencies of the existing technology. A simple four-legged ramp walker that only relies on its own gravity to go downhill is designed by using joints made of elastic materials and a plug-in structure. The gravitational potential energy of the elastic joints during the walker's downhill process is converted into elastic potential energy for storage and release, so as to achieve the purpose of stable downhill, thereby affecting the motion state of the robot. The walker has a simple structure, each component adopts a plug-in design, and elastic materials are introduced to achieve the feasibility of stable walking under a non-hinge structure. It can be equipped with a variety of accessories, supporting the change of multiple parameters such as leg length, joint hardness, body width, inclined friction coefficient, etc. It can be used as an innovative teaching aid, applied to popular science demonstrations and youth scientific and technological exploration of mechanics and materials science, develop the intelligence and creativity of young people, and has a good educational demonstration effect.

[0004] The specific technical scheme for achieving the purpose of the present invention is: a popular science teaching aid of a passively powered ramp walker with elastic joints, characterized in that the joints are made of elastic material, and a four-legged ramp walker is designed through an extremely simple structure to achieve the purpose of stable descent. The walker adopts a simulated body skeleton and four simulated legs and their four simulated joints to form a four-legged ramp walker that only relies on its own gravity to go downhill. The simulated body skeleton is a walker skeleton with four rectangular joint A interfaces in the same direction; the simulated legs are rectangular sheets, the upper end of which is provided with a rectangular joint B interface, the lower end is an arc edge, and the center of the lower arc is located on the long side of the rectangular sheet; the simulated joints are composed of a ring connector made of elastic material and two rectangular cavities to form a right-angle structure component, the rectangular cavity at one end of which is plugged into the rectangular joint A interface of the simulated body skeleton, and the rectangular cavity at the other end is plugged into the rectangular joint B interface of the simulated leg. Similarly, the remaining three simulated joints are respectively plugged into the simulated body and the simulated legs to form a four-legged ramp walker with elastic joints that can passively walk downhill.

[0005] The simulated body skeleton is a thin sheet with four rectangular joint interfaces in the same direction, which ensures that the swinging directions of the legs on the same side are consistent.

[0006] The annular connector of the simulated joint is made of elastic material such as TPU, which is elastic and ensures that the legs can swing forward and backward. The openings at both ends of the simulated joint are connected to the body and the legs respectively. The other parts of the simulated joint are made of rigid materials such as PLA.

[0007] The simulation leg is a rectangular thin sheet with an arc on one side, and the center of the lower arc is located on the edge. The bottom of the simulation leg is an arc structure to ensure that it swings left and right.

[0008] A walking method of a popular science teaching aid of a passive power ramp walker with elastic joints, characterized in that the walking of the passive power ramp walker specifically includes the following steps: Step 1: Build a walking ramp, making sure its surface is vertical and has a certain angle; Step 2: Assemble a quadruped ramp walker with flexible joints and passive descent; Step 3: Place the walker on the slope, tilt it slightly to the left or right, and then release it; Step 4: Observe the walking state of the walker and adjust the inclination angle appropriately so that the walker can go downhill stably.

[0009] The inclination angle of the slope constructed in step 1 is between 6° and 11°, and the friction coefficient between the slope and the simulated leg of the walker must be greater than 0.1.

[0010] The assembly of the walker in step 2 includes: Step A1: insert the four rectangular joint A interfaces of the simulated body skeleton into the rectangular cavities at one end of the four simulated joints respectively; Step A2: Insert the rectangular joint B interfaces at the upper ends of the four simulated legs into the rectangular cavities at the other ends of the four simulated joints, and ensure that the arc parts of the four simulated legs face outwards.

[0011] When the elasticity of the annular connecting member simulating the joint in step three is released, the roll angle thereof is less than 10°.

[0012] The walking device walking in step 4 includes the following walking states: 1) The walker swings left and right when walking, and when it swings to one side, the other leg is lifted; 2) After the walker swings sideways, the two legs touching the ground lean forward, and the two legs in the air swing forward; 3) The leg touching the ground during walking is stationary relative to the inclined plane and does not slide; 4) The movement state of the legs on the same side is the same during walking.

[0013] Compared with the prior art, the present invention has a simple structure, each component adopts a plug-in design, and introduces elastic materials, realizing the feasibility of stable walking under a non-hinge structure. It can be equipped with a variety of accessories, supporting the change of leg length, joint hardness, body width, inclined friction coefficient and other parameters. It can be used as an innovative teaching aid, applied to the popularization of mechanics and materials science and the scientific and creative exploration of young people, developing the intelligence and creativity of young people, and has a good educational demonstration effect. BRIEF DESCRIPTION OF THE DRAWINGS

[0014] Figure 1 It is a schematic structural diagram of the elastic joint passive power ramp walker of the present invention; Figure 2 for Figure 1 A top view of Figure 3 It is a schematic diagram of the structure of the simulated leg; Figure 4 Schematic diagram of the structure of the simulated joint. DETAILED DESCRIPTION

[0015] See also Figure 1-2The walker is composed of a simulated body skeleton 1 and four simulated legs 2 and four simulated joints 3. The simulated body skeleton 1 is a walker skeleton with four rectangular joint A interfaces 11-4 in the same direction; the simulated leg 2 is a rectangular sheet, the upper end of which is provided with a rectangular joint B interface 22, the lower end is a circular arc edge 21, and the center of the lower circular arc is located on the long side 23 of the rectangular sheet; the simulated joint 3 is a right-angle structure component composed of an annular connector 33 made of elastic material and two rectangular cavities 31-2, the rectangular cavity 31 at one end is plugged into the rectangular joint A interface 11 of the simulated body skeleton 1, and the rectangular cavity 32 at the other end is plugged into the rectangular joint B interface 22 of the simulated leg 2. Similarly, the remaining three simulated joints 3 are respectively plugged into the simulated body 1 and the simulated leg 2 to form a four-legged ramp walker with elastic joints that can passively walk downhill.

[0016] See also Figure 3 The simulated leg 2 is a rectangular sheet, with a rectangular joint B interface 22 at its upper end and an arc edge 21 at its lower end, and the center of the lower arc is located on the long side 23 of the rectangular sheet.

[0017] See also Figure 4 The simulated joint 3 is a component of a right-angle structure consisting of an annular connecting piece 33 made of elastic material and two rectangular cavities 31-2. The rectangular cavity 31 at one end is plugged into the rectangular joint A interface 11 of the simulated body skeleton 1, and the rectangular cavity 32 at the other end is plugged into the rectangular joint B interface 22 of the simulated leg 2.

[0018] The simulated body skeleton 1 is printed with a material with relatively high rigidity, such as PLA material, to ensure that the overall structure of the walker is stable and does not bend. The simulated body skeleton 1 has four unidirectional rectangular joint A interfaces 11-4, which are connected to the simulated joint 3 and ensure that the leg swing phases are the same; the annular connector 33 of the simulated joint 3 is printed with an elastic material, such as TPU material, to ensure the forward and backward swinging of the simulated leg 2 and the limiting and energy storage of this process; the simulated leg 2 has an arc edge 21 to ensure and promote the left and right swinging of the walker, and its center is located on the long side 23. Without this arc, the walker cannot walk, and if it is not an arc, its walking stability will be limited; at the same time, the upper end of the simulated leg 2 is a rectangular joint B interface 22, which is connected to the joint; the simulated joint 3 is a right-angle structure, with rectangular cavities 31-2 at both ends, and the right-angle connection is a ring connector 33 to reduce the elastic modulus. Since the walking state of the walker is greatly affected by its structure, in order to find its optimal walking structure, the structure and connection of the four simulated legs 2 are unified, reducing the test variables, and multiple parameters are designed for regulation to accurately change a certain parameter of the walker, such as increasing the thickness of the annular connector 33 of the simulated joint 3 to increase its elastic modulus.

[0019] The walking of the passive power ramp walker specifically comprises the following steps: Step 1: Build a walking ramp, ensure that its surface is vertical and has a certain angle. The friction coefficient of the ramp should be as large as possible, and materials such as wood can be used. When building, ensure that the left and right directions of the ramp are horizontal to prevent the walker from deviating from the straight line due to disturbances. At the same time, avoid bending due to the length of the ramp, and ensure the stability of the angles of the ramp at all levels.

[0020] Step 2: Assemble a simple quadruped ramp walker with elastic joints for passive descent, insert the joint interface of the body into the cavity on the joint, and insert the leg into another cavity of the joint, making sure the long side of the leg faces inward.

[0021] Step 3: Place the walker on an inclined plane, tilt it slightly to the left or right at a certain angle, release the elasticity of the annular connector 33, and ensure that the body joint interface of the walker faces forward when placing it.

[0022] Step 4: Observe the walking state of the walker and adjust the inclination angle appropriately so that the walker can stably go downhill. If the inclination angle is still not stable, the walker parameters can be adjusted appropriately according to its movement state. If the walker always flips forward, the thickness of the joint ring can be increased to increase its elastic coefficient.

[0023] The walking state of the walker includes: 1) the walker swings left and right when walking, and the leg on the other side is lifted when swinging to one side; 2) the two legs touching the ground lean forward after the walker swings sideways, and the two legs suspended in the air swing forward; 3) the leg touching the ground is stationary relative to the inclined plane during the walking process of the walker and does not slide; 4) the movement state of the legs on the same side is basically the same during the walking process of the walker.

[0024] The following is a further detailed description of the features of the present invention and other related features by using a set of data as an embodiment in conjunction with the accompanying drawings, so as to facilitate the understanding of technicians in the same industry: Example

[0025] In this embodiment, the thickness of the simulated body frame 1 and the simulated leg 2 is 1mm, wherein the simulated body frame 1 is 120mm long and 80mm wide, the joint interface (rectangular joint A interface 11-4) cut out in the middle is 20mm wide, the front and rear interface spacing is about 40mm, and the interface spacing is 40mm. Considering the margin during connection, the joint interface width is slightly smaller than 20mm. The simulated leg 2 is 100mm long, slightly less than 20mm wide, and the radius of the arc portion is 50mm. The joint cavity (rectangular cavity 31-2) is 1mm thick, 20mm wide, and 20mm long. The outer wall of the cavity is 1mm thick, and the thickness of the annular connector 33 is 2mm.

[0026] The length of the inclined plane built in this embodiment is 2.44m. After testing, the walker can walk stably within the range of 6°~11° and reach the final stable speed. When the annular connector 33 releases its elasticity, the release angle is less than 10°. The walker can find the most suitable swing amplitude in each iteration and achieve stability. During the walking process, try to put sandpaper on the inclined plane to increase friction. The walker can still walk stably and is closer to the ideal stable walking state. Example

[0027] In the present embodiment, the simulated body skeleton 1 and the simulated leg 2 are 1mm, wherein the entire length of the simulated body skeleton 1 is 240mm, the width is 140mm, the joint interface cut out in the middle is 40mm wide, the front and rear interface spacing is about 80mm, and the interface spacing is 80mm. Considering the margin during connection, the joint interface width is slightly smaller than 40mm. The simulated leg 2 is 200mm long, slightly less than 40mm wide, and the radius of the arc portion is 100mm. The joint cavity is 2mm thick, 40mm wide, and 40mm long. The outer wall thickness of the cavity is 2mm, and the annular connection thickness is 4mm. After adjusting the inclined plane inclination angle and the release inclination angle, the walker can achieve stable walking on the inclined plane.

[0028] The protection content of the present invention is not limited to the above embodiments. Without departing from the spirit and scope of the inventive concept, changes and advantages that can be thought of by those skilled in the art are included in the present invention and are protected by the attached claims.

Claims

1. A popular science teaching aid of a flexible joint and passive power ramp walker, characterized in that: A four-legged ramp walker that can go downhill only by its own gravity is composed of a simulated body skeleton, four simulated legs and four simulated joints. The simulated body skeleton is a walker skeleton with four rectangular joint A interfaces in the same direction. The simulated legs are rectangular sheets with rectangular joint B interfaces at the upper end and circular arc edges at the lower end, and the center of the lower circular arc is located on the long side of the rectangular sheet. The simulated joints are components of a right-angle structure composed of an annular connector made of elastic material and two rectangular cavities. The rectangular cavity at one end is plugged into the rectangular joint A interface of the simulated body skeleton, and the rectangular cavity at the other end is plugged into the rectangular joint B interface of the simulated leg. Similarly, the remaining three simulated joints are respectively plugged into the simulated body skeleton and the simulated legs to form a four-legged ramp walker with elastic joints that can passively walk downhill.

2. The popular science teaching aid of the elastic joint and passive power ramp walker according to claim 1, characterized in that: The annular connector of the simulated joint is made of TPU elastic material, and the rectangular cavities at both ends of the simulated joint are made of PLA rigid material.

3. A walking method of a science popularization teaching aid of a flexible joint and passive power ramp walker, characterized in that: The walking of the passive power ramp walker specifically comprises the following steps: Step 1: Build a walking ramp, making sure its surface is vertical and has a certain angle; Step 2: Assemble a quadruped ramp walker with elastic joints and passive downhill movement; Step 3: Place the walker on the built slope, tilt it slightly left or right to release the elasticity of the ring connector; Step 4: Observe the walking state of the walker and adjust the inclination angle appropriately so that the walker can go downhill stably.

4. The walking method of the popular science teaching aid of the elastic joint and passive power ramp walker according to claim 3 is characterized in that: The inclination angle of the slope constructed in step 1 is between 6° and 11°, and the friction coefficient between the slope and the simulated leg is greater than 0.

1.

5. The walking method of the popular science teaching aid of the elastic joint and passive power ramp walker according to claim 3 is characterized in that: The walker assembly of step 2 includes: Step A1: insert the four rectangular joint A interfaces of the simulated body skeleton into the rectangular cavities at one end of the four simulated joints respectively; Step A2: Insert the rectangular joint B interfaces at the upper ends of the four simulated legs into the rectangular cavities at the other ends of the four simulated joints, respectively, and make the arc parts of the four simulated legs face outwards.

6. The walking method of the popular science teaching aid of the elastic joint and passive power ramp walker according to claim 3 is characterized in that: The roll angle of the annular connecting member when released in step three is less than 10°.

7. The walking method of the popular science teaching aid of the elastic joint passive power ramp walker according to claim 3, characterized in that: The walker in step 4 includes the following walking states when walking: 1) The walker swings left and right when walking, and when it swings to one side, the other leg is lifted; 2) After the walker swings sideways, the two legs touching the ground lean forward, and the two legs in the air swing forward; 3) The leg that touches the ground during walking on the walker is stationary relative to the inclined plane; 4) The movement state of the legs on the same side is the same during walking.

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