A bionic frog robot with posture adjustment

Abstract

The application discloses a bionic frog robot with posture adjustment, which comprises forelimbs, hind limbs and a body frame, a front rotating shaft is arranged at the front of the body frame, the forelimbs are arranged on the front rotating shaft, a front driving motor and a posture sensor are arranged on the upper surface of the body frame, the front driving motor drives the front rotating shaft to rotate through a vertical transmission mode, a rear rotating shaft is arranged at the rear of the body frame, the two ends of the rear rotating shaft are arranged at eccentric positions of a cam, a rear driving motor is arranged on the upper surface of the body frame, the rear driving motor drives the rear rotating shaft to rotate through a vertical transmission mode, the front end of the hind limbs is a frog-shaped palm, a guide is arranged at the rear end of the hind limbs, and the guide is connected with a stand column of the body frame through a force storage spring; the cam phase locking technology is applied to the jumping robot, and a three-stage cam structure realizes a working cycle of "energy storage-locking-releasing", so that not only continuous jumping is realized, but also the interval of the continuous jumping is greatly shortened.

Description

TECHNICAL FIELD

[0001] The application belongs to the technical field of bionic robots, and particularly relates to a bionic frog robot with posture adjustment. BACKGROUND

[0002] A bionic robot refers to a robot that imitates a living being and performs work with biological characteristics. Frogs can easily jump over obstacles with a strong explosive jump and a long distance, and have good environmental adaptability. The biological structure and behavior of frogs are reasonable, flexible and efficient. At present, bionic frog robots have been researched and developed at home and abroad. The overall structure of a bionic frog mainly includes forelimbs, hindlimbs and a body. For the forelimb part, in existing jumping robots, the buffer when the robot lands is mostly a fixed passive buffer scheme, that is, the buffer device only starts to work after contacting the ground. This not only has a slow response speed, but also has poor buffer effect. The hindlimb part mostly uses a linkage mechanism to imitate a joint, such as the existing patent document CN118343223A, but the linkage mechanism has a large degree of freedom, and after being charged by a spring, the landing posture of the bionic frog cannot be effectively guaranteed. SUMMARY

[0003] Based on the problems in the background art, the application provides a bionic frog robot with posture adjustment. Compared with a traditional passive buffer mechanism, the response speed is improved. The bionic frog robot realizes a similar jumping motion to a real bionic frog through precise motor control and sensor feedback.

[0004] To achieve the above purpose, the technical scheme adopted by the application is as follows:

[0005] A bionic frog robot with posture adjustment, the bionic frog robot comprising forelimbs, hindlimbs and a body frame, characterized in that: a front rotating shaft is installed at the front of the body frame, the forelimbs are installed on the front rotating shaft, a front driving motor and a posture sensor are installed on the upper surface of the body frame, the front driving motor drives the front rotating shaft to rotate through a vertical transmission mode, a rear rotating shaft is installed at the rear of the body frame, the two ends of the rear rotating shaft are installed at eccentric positions of a cam, a rear driving motor is installed on the upper surface of the body frame, the rear driving motor drives the rear rotating shaft to rotate through a vertical transmission mode, the front end of the hindlimb is a frog-shaped palm, a guide is installed at the rear end of the hindlimb, and the guide is connected to the stand column of the body frame through a force storage spring; the front end of a hindlimb fixing part is connected to the body frame, the middle part of the hindlimb fixing part is penetrated by the rear rotating shaft, and the rear end is hingedly connected to a central shaft between the two cams, and a streamlined pot-shaped outer shell is installed on the top of the body frame.

[0006] Further, the front driving motor and the rear driving motor are both step motors, the step motor is vertically driven through two straight bevel gears, and the front driving motor power is transmitted to the front rotating shaft, and the rear driving motor power is transmitted to the rear rotating shaft.

[0007] Further, the forelimb is designed in an arc shape.

[0008] Further, the cam is based on a substantially circular shape, and the top of the cam is designed in a groove shape, and the right side of the groove is gradually convex.

[0009] Further, the guide is a cylindrical connecting rod, which is installed at the rear end of the hind limb, and when the cam rotates, the cam profile rotates along the guide.

[0010] Further, the body frame is installed with three columns, and the three columns support the shell.

[0011] Further, the upper surface of the body frame is installed with motor placing grooves in front and rear, and the step motor and the attitude sensor are installed in the motor placing grooves.

[0012] The above technical scheme can obtain the following beneficial effects:

[0013] The application adopts the active buffering technology features of the straight bevel gear and the attitude sensor, and the response speed is improved compared with the traditional passive buffering mechanism. Through the front rotating shaft mechanism, the forelimb can be expanded to a larger angle, and the obtuse arc shape has more contact area with the ground, which can better absorb the impact during landing.

[0014] The application applies the cam phase locking technology to the jumping robot, and the three-stage cam structure realizes the working cycle of "energy storage-locking-release", which not only realizes continuous jumping, but also greatly shortens the interval of continuous jumping. BRIEF DESCRIPTION OF DRAWINGS

[0015] Fig. 1 It is a partial structure diagram of the bionic frog robot.

[0016] Fig. 2 It is a whole structure diagram of the bionic frog robot.

[0017] Fig. 3 It is a partial schematic diagram of the hind limb of the bionic frog robot.

[0018] In the figure:

[0019] In the figure: 1, body frame; 2, forelimb; 3, hind limb; 4, front rotating shaft; 5, cam; 6, frog-shaped palm; 7, guide, 8, hind limb fixing part, 9, central shaft, 10, shell, 11, column, 12, rear rotating shaft, 13, attitude sensor. DETAILED DESCRIPTION

[0020] The application will be further described below in conjunction with the accompanying drawings:

[0021] As Figs. 1-3 shown, a bionic frog robot with posture adjustment includes forelimbs 2, hind limbs 3 and a body frame 1, the front of the body frame is provided with a front rotating shaft, the front rotating shaft 4 is provided with the forelimbs 2, the forelimbs are designed in an arc shape, a front driving motor is installed on the upper surface of the body frame, the front driving motor drives the front rotating shaft to rotate through a vertical transmission mode, the rear of the body frame is provided with a rear rotating shaft 12, the two ends of the rear rotating shaft are installed at the eccentric positions of a cam 5, a rear driving motor is installed on the upper surface of the body frame, the rear driving motor drives the rear rotating shaft to rotate through a vertical transmission mode, the front end of the hind limb 3 is a frog-shaped palm 6, the rear end of the hind limb 3 is provided with a guide 7, the guide is a cylindrical connecting rod, which is installed at the rear end of the hind limb, one end of a force storage spring is connected to the connecting rod, and the other end is connected to a vertical column 11, when the cam rotates, the cam profile rotates along the guide, the front end of a hind limb fixing part 8 is connected to the body frame, the rear rotating shaft passes through the middle part of the hind limb fixing part 8, and the rear end is hinged to a central shaft 9 between the two cams 5, the two ends of the central shaft 9 are respectively provided with the centers of the two cams, and a streamlined bucket-shaped shell 10 is installed on the top of the body frame 1.

[0022] Based on the above embodiment, the front and rear driving motors are installed in motor placing grooves, the front and rear driving motors are step motors, for the forelimbs, two straight bevel gears are used as transmission devices, the step motor drives the rotation of the driving straight bevel gear, then the driving straight bevel gear is engaged with the driven straight bevel gear, the driven straight bevel gear is installed on the front rotating shaft, and the front rotating shaft is provided with two forelimbs, a posture sensor 13 is fixed above the front motor, which is used for detecting the current state of the frog; an esp32 development board is placed above the rear motor, which is used for receiving signals and controlling the circuit system of the whole robot. When the frog jumps, after the posture sensor detects the jumping signal, the step motor drives the forelimbs to stretch forward to reduce the impact force when landing; in addition, the forelimbs are designed in an arc shape, which increases the contact area of the forelimbs with the ground when landing, reduces the ground pressure, and realizes soft landing.

[0023] For the hind legs of the frog, the hind leg sole part is designed into a frog-shaped palm shape for better grip. The hind leg part has two pivot shafts for driving the rotation of the cam and the swing of the hind leg, and the rotation power is transmitted through a bevel gear, and the rotation power comes from a stepping motor. The power for jumping comes from the stretching of the spring by the cam. One end of the spring is connected to the upper end link of the hind leg, and the other end is connected to the fixed platform (stand) of the rear motor, so that when the spring contracts, the hind leg will make a backward kicking action. This embodiment designs a three-stage cam structure: first, the push stage, the curvature of the cam gradually increases, which will push the upper end link of the hind leg, so that the spring of the hind leg part can be stretched, which corresponds to the power accumulation stage of the bionic frog hind leg; then enter the stop stage, at this stage, the cam stops rotating, and the foreleg is adjusted to the appropriate position under the action of the stepping motor; finally, the cam continues to rotate, enters the return stage, and the shape of the return stage is a concave curve, which can make the elastic potential energy of the hind leg spring release in a short time to achieve the jumping effect. The transmission structure of the hind leg is the same as that of the foreleg, that is, one straight bevel gear drives another straight bevel gear to rotate, and then further drives the rear pivot shaft to rotate. Due to the special structure of the cam and its shape characteristics of the "return stage", the frog can jump continuously.

[0024] In addition, the shell of the robot is designed as a streamlined bucket-shaped shell, which has a large internal space and can place control circuit system, and also has the function of adjusting the center of gravity during jumping.

[0025] The cam shape of the robot is approximately oval as a whole, and the top is concave. The profile of the cam is a closed curve with high continuity and smoothness, without sharp points or corners, ensuring smooth transition of the profile during rotation. The cam has an inwardly recessed area, the left side of the recessed area is convex with a small radius, and the right side of the recessed area is convex with a large radius, but the curvature change still has continuity, without sudden change of curvature.

[0026] Due to the special shape of the cam, after the frog jumps, the connecting link of the spring will return to the original position due to the partial concave of the cam, so that the frog can enter the state of preparing for the next jump, that is, the frog can jump continuously.

[0027] Through the attitude sensor, the foreleg can automatically adjust its position by changing the rotation angle of the stepping motor, reduce the buffer force when landing, and realize soft landing.

[0028] The transmission of the whole robot is completed by gears and cams, and the energy loss is only in the driving of the stepping motor, so the invention also reduces the energy consumption and improves the energy use efficiency.

[0029] The above are preferred embodiments of the present application, and modifications of various equivalent forms of the present application made on the basis of the principle of the present application without departing from the scope of the present application belong to the scope of protection of the claims of the present application.

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: The front of the body frame is provided with a front rotating shaft, the front rotating shaft (4) is provided with a front leg (2), a front driving motor and a posture sensor are arranged on the upper surface of the body frame, the front driving motor drives the front rotating shaft to rotate through a vertical transmission, the rear of the body frame is provided with a rear rotating shaft, the two ends of the rear rotating shaft are arranged at the eccentric positions of a cam (5), a rear driving motor is arranged on the upper surface of the body frame, the rear driving motor drives the rear rotating shaft to rotate through a vertical transmission, the front end of the rear leg (3) is provided with a frog-shaped palm (6), the rear end of the rear leg (3) is provided with a guide (7), the guide (7) is connected with the stand of the body frame through a force storage spring; the front end of a rear leg fixing member (8) is connected with the body frame, the rear rotating shaft passes through the middle part of the rear leg fixing member (8), the rear end is hingedly connected to a central shaft (9) between the two cams (5), the top of the body frame (1) is provided with a streamlined pot-shaped shell (10); the front driving motor and the rear driving motor are both step motors, the step motors are provided with two straight bevel gears to form a vertical transmission, the front driving motor drives the front rotating shaft, and the rear driving motor drives the rear rotating shaft; the front leg is designed in an arc shape; the front and rear of the upper surface of the body frame are provided with motor placing grooves, the motor placing grooves are provided with step motors and posture sensors.

2. The biomimetic frog robot with posture adjustment according to claim 1, characterized in that: The cam is based on a basic circular plane, and the top of the cam is designed in a groove shape, and the right side of the groove is gradually convex in a curve profile.

3. The biomimetic frog robot with posture adjustment according to claim 1, characterized in that: The guide (7) is a cylindrical connecting rod, and is arranged at the rear end of the rear leg (3), when the cam rotates, the cam profile rotates along the guide.

4. The biomimetic frog robot with posture adjustment according to claim 1, characterized in that: The body frame (1) is provided with three stands, and the three stands support the shell (10).

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