Bionic frog robot with posture adjustment function

Abstract

The bionic frog robot comprises front limbs, rear limbs and a body frame, a front rotating shaft is installed in front of the body frame, the front limbs are installed on the front rotating shaft, and a front driving motor and an attitude sensor are installed on the upper surface of the body frame; the front driving motor drives the front rotating shaft to rotate in a vertical transmission mode, the rear rotating shaft is installed on the rear portion of the body frame, the two ends of the rear rotating shaft are installed at the eccentric positions of the cams, the rear driving motor is installed on the upper surface of the body frame and drives the rear rotating shaft to rotate in a vertical transmission mode, and frog-shaped palms are arranged at the front ends of the posterior limbs. Guiding pieces are mounted at the rear ends of the hind limbs and connected with the stand columns of the body frame through force storage springs; the cam phase locking technology is applied to the jumping robot, the three-stage cam structure achieves the work cycle of energy storage, locking and releasing, continuous jumping is achieved, and the interval of continuous jumping is greatly shortened.

Description

Technical Field

[0001] This invention belongs to the field of biomimetic robot technology, specifically relating to a biomimetic frog robot with posture adjustment capabilities. Background Technology

[0002] Bionic robots are robots that mimic biological organisms and perform tasks based on their characteristics. Frogs, with their explosive and long-distance jumps, easily overcome obstacles and exhibit excellent environmental adaptability. Their biological structure and behavior are rational, flexible, and efficient. Currently, both domestic and international researchers are engaged in the research and development of bionic frog robots. The overall structure of a bionic frog mainly includes forelimbs, hindlimbs, and the body. For the forelimbs, existing jumping robots mostly use fixed, passive cushioning schemes for landing, meaning the cushioning device only activates after contact with the ground. This results in slow response and poor cushioning effect. The hindlimbs often use linkage mechanisms to mimic joints, such as in the existing patent document CN118343223A, which describes a bionic frog robot. However, the linkage mechanism has a relatively large degree of freedom, and relying solely on spring force cannot effectively guarantee a normal landing posture for the bionic frog. Summary of the Invention

[0003] Based on the problems existing in the background technology, the present invention proposes a biomimetic frog robot with posture adjustment. Compared with the traditional passive buffer mechanism, the response speed is improved. The biomimetic frog robot achieves jumping motion similar to that of a real biomimetic frog through precise motor control and sensor feedback.

[0004] To achieve the above objectives, the technical solution adopted by the present invention is as follows: A biomimetic frog robot with posture adjustment is disclosed. The biomimetic frog robot includes forelimbs, hindlimbs, and a body frame. The robot is characterized by: a front rotating shaft mounted at the front of the body frame, with the forelimbs mounted on the front rotating shaft; a front drive motor and a posture sensor mounted on the upper surface of the body frame; the front drive motor drives the front rotating shaft to rotate via vertical transmission; a rear rotating shaft mounted at the rear of the body frame, with both ends mounted to the eccentric points of cams; a rear drive motor mounted on the upper surface of the body frame; the rear drive motor drives the rear rotating shaft to rotate via vertical transmission; the front end of the hindlimbs is a frog-shaped paw; a guide is mounted at the rear end of the hindlimbs; the guide is connected to the column of the body frame via a storage spring; the front end of the hindlimb fixing member is connected to the body frame; the rear rotating shaft passes through the middle of the hindlimb fixing member; and the rear end is hinged to the central shaft between two cams; a streamlined, gourd-shaped outer shell is mounted on the top of the body frame.

[0005] Furthermore, both the front drive motor and the rear drive motor are stepper motors. The stepper motors form a vertical transmission through two straight bevel gears, which transmit the power of the front drive motor to the front shaft and the power of the rear drive motor to the rear shaft.

[0006] Furthermore, the forelimbs are designed in an arch shape.

[0007] Furthermore, the cam is based on a basic circle, with a groove shape designed at the top of the cam, and the right side of the groove has a gradually convex curved profile.

[0008] Furthermore, the guide is a cylindrical connecting rod, installed at the rear end of the hind limb, and when the cam rotates, the cam profile rotates along the guide.

[0009] Furthermore, the body frame is fitted with three pillars, which support the outer shell.

[0010] Furthermore, motor mounting slots are installed at the front and rear of the upper surface of the body frame, and stepper motors and attitude sensors are installed in the motor mounting slots.

[0011] The above technical solution can achieve the following beneficial effects: This invention employs active cushioning technology featuring straight bevel gears and attitude sensors, resulting in improved response speed compared to traditional passive cushioning mechanisms. The front pivot mechanism allows for a greater forelimb deployment angle, and the obtuse-angled bow shape provides a larger contact area with the ground, better absorbing the impact upon landing.

[0012] This invention applies cam phase locking technology to a jumping robot. The three-stage cam structure realizes the "energy storage-locking-release" working cycle, which not only enables continuous jumping, but also greatly shortens the interval between continuous jumping. Attached Figure Description

[0013] Figure 1 This is a partial structural diagram of a biomimetic frog robot.

[0014] Figure 2 This is a structural diagram of the biomimetic frog robot.

[0015] Figure 3 This is a partial schematic diagram of the hind limbs of a biomimetic frog robot.

[0016] In the picture: In the diagram: 1. Body frame; 2. Forelimbs; 3. Hindlimbs; 4. Front pivot; 5. Cam; 6. Frog-shaped paw; 7. Guide; 8. Hindlimb fixation; 9. Central axis; 10. Shell; 11. Column; 12. Rear pivot; 13. Attitude sensor. Detailed Implementation

[0017] The invention will be further described below with reference to the accompanying drawings: like Figure 1-3 As shown, a biomimetic frog robot with posture adjustment is disclosed. The biomimetic frog robot includes forelimbs 2, hindlimbs 3, and a body frame 1. A front rotating shaft 4 is installed at the front of the body frame, and the forelimbs 2 are mounted on the front rotating shaft 4. The forelimbs are designed in an arc shape. A front drive motor is installed on the upper surface of the body frame, and the front drive motor drives the front rotating shaft to rotate through a vertical transmission method. A rear rotating shaft 12 is installed at the rear of the body frame, and the two ends of the rear rotating shaft are mounted to the eccentric parts of a cam 5. A rear drive motor is installed on the upper surface of the body frame, and the rear drive motor drives the rear rotating shaft to rotate through a vertical transmission method. The front end of the hind limb 3 is a frog-shaped paw 6, and the rear end of the hind limb 3 is equipped with a guide 7. The guide is a cylindrical connecting rod and is installed at the rear end of the hind limb. One end of the energy storage spring is connected to the connecting rod, and the other end is connected to the column 11. When the cam rotates, the cam profile rotates along the guide. The front end of the hind limb fixing member 8 is connected to the body frame. The rear rotating shaft passes through the middle of the hind limb fixing member 8, and the rear end is hinged to the central shaft 9 between the two cams 5. The centers of the two cams are respectively installed at both ends of the central shaft 9. A streamlined gourd-shaped outer shell 10 is installed on the top of the body frame 1.

[0018] Based on the above embodiment, both the front and rear drive motors are installed in the motor placement slot. Both drive motors are stepper motors. For the forelimbs, two bevel gears serve as the transmission device. The stepper motor drives the rotation of the driving bevel gear, which then meshes with the driven bevel gear. The driven bevel gear is mounted on the front shaft, which also houses the two forelimbs. Above the front motor, a posture sensor 13 is fixedly mounted to detect the frog's current state. Above the rear motor, an ESP32 development board is placed to receive signals and control the robot's circuitry. When the frog jumps, the posture sensor detects the jump signal, and the stepper motor drives the forelimbs to extend forward to reduce the impact force upon landing. Furthermore, the forelimbs are designed in an arch shape, increasing the contact area between the forelimbs and the ground upon landing, reducing ground pressure, and achieving a soft landing.

[0019] For the frog's hind limbs, the foot portion is designed in a frog-like palm shape for better grip. The hind limbs have two pivots, one for driving the rotation of the cam and the other for the swinging of the hind limbs, driven by a bevel gear transmission. The rotational power comes from a stepper motor. The power for jumping comes from the cam stretching a spring. One end of the spring is connected to the upper connecting rod of the hind limb, and the other end is connected to the fixed platform (column) of the rear motor. Therefore, when the spring contracts, the hind limb makes a backward pushing motion. This embodiment designs a three-stage cam structure: first, the push-stroke stage, where the curvature of the cam gradually increases, pushing the upper connecting rod of the hind limb, stretching the spring in the hind limb, corresponding to the power-gathering stage of the biomimetic frog's hind leg; then, the stopping stage, where the cam stops rotating, and the forelimb, under the action of the stepper motor, adjusts to the appropriate position; finally, the cam continues to rotate, entering the return stage. The return stage corresponds to the shape of the cam being a concave curve, allowing the elastic potential energy of the hind leg spring to be released in a short time, achieving the jumping effect. The transmission structure of the hind limbs is the same as that of the forelimbs, with one bevel gear driving another bevel gear to rotate, which in turn drives the rear shaft to rotate. Due to the special structure of the cam and its shape characteristic of having a "return phase", the frog can make continuous jumps.

[0020] In addition, the robot's shell is designed as a streamlined gourd shape, which has a large internal space to house the control circuit system and also serves to adjust the center of gravity during jumps.

[0021] The robot's cam is approximately oval in shape, with a concave top. The cam's profile is a closed curve, exhibiting high continuity and smoothness, without sharp points or angles, ensuring a smooth transition of the profile during rotation. The cam has an inwardly concave region; the left side of this region has a slight convexity, while the right side has a larger convexity, but the curvature change remains continuous, without abrupt changes.

[0022] Due to the special shape of the cam, after the frog jumps, the connecting rod of the spring will return to its original position because of the partial concavity of the cam, thus enabling the frog to enter the state of preparing for the next jump, which realizes the continuous jumping of the frog.

[0023] Using attitude sensors, the forelimbs automatically adjust their position by changing the rotation angle of the stepper motor, reducing the cushioning force upon landing and achieving a soft landing.

[0024] The entire robot's transmission is accomplished by gears and cams, with energy loss occurring only in the stepper motor's drive. Therefore, this invention also reduces energy consumption and improves energy efficiency.

[0025] The above descriptions are all preferred embodiments of the present invention. For those skilled in the art, any modifications to the present invention in various equivalent forms without departing from the principle of the present invention shall fall within the protection scope of the appended claims.

Claims

1. A biomimetic frog robot with posture adjustment, the biomimetic frog robot comprising forelimbs (2), hindlimbs (3) and a body frame (1), characterized in that: A front pivot is installed at the front of the body frame, and the front pivot (4) is installed with the forelimb (2). A front drive motor and an attitude sensor are installed on the upper surface of the body frame. The front drive motor drives the front pivot to rotate through vertical transmission. A rear pivot is installed at the rear of the body frame. The two ends of the rear pivot are installed at the eccentric part of the cam (5). A rear drive motor is installed on the upper surface of the body frame. The rear drive motor drives the rear pivot to rotate through vertical transmission. The front end of the hind limb (3) is a frog-shaped palm (6). A guide (7) is installed at the rear end of the hind limb (3). The guide (7) is connected to the column of the body frame through a storage spring. The front end of the hind limb fixing part (8) is connected to the body frame. The rear pivot passes through the middle of the hind limb fixing part (8). The rear end is hinged to the central shaft (9) between the two cams (5). A streamlined gourd-shaped shell (10) is installed on the top of the body frame (1).

2. The biomimetic frog robot with posture adjustment according to claim 1, characterized in that: Both the front drive motor and the rear drive motor are stepper motors. The stepper motors form a vertical transmission through two straight bevel gears, which transmit the power of the front drive motor to the front shaft and the power of the rear drive motor to the rear shaft.

3. The biomimetic frog robot with posture adjustment according to claim 1, characterized in that: The forelimbs are designed in an arch shape.

4. A biomimetic frog robot with posture adjustment according to claim 1, characterized in that: The cam is based on a circle, with a groove shape at the top of the cam and a gradually convex curved profile on the right side of the groove.

5. A biomimetic frog robot with posture adjustment according to claim 1, characterized in that: The guide (7) is a cylindrical connecting rod, installed at the rear end of the hind limb (3). When the cam rotates, the cam profile rotates along the guide.

6. A biomimetic frog robot with posture adjustment according to claim 1, characterized in that: The body frame (1) is fitted with three columns, which support the outer shell (10).

7. A biomimetic frog robot with posture adjustment according to claim 1, characterized in that: Motor placement slots are installed on the front and rear of the upper surface of the body frame, and stepper motors and attitude sensors are installed in the motor placement slots.

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