Reconfigurable air-land amphibious robot

Abstract

A reconfigurable air-land amphibious robot relates to the technical field of robots and comprises a robot main body, a deformation mechanism, a main control unit and a comprehensive movement mechanism, the deformation mechanism is used for driving the comprehensive movement mechanism to act and switching the operation state of the comprehensive movement mechanism; the running state of the comprehensive movement mechanism comprises a flight mode and a walking mode, and the comprehensive movement mechanism is used for executing a flight action in the flight mode and executing a walking action in the walking mode; the main control unit is electrically connected with the deformation mechanism and the comprehensive movement mechanism; the amphibious robot is used for solving the problems that a traditional amphibious robot is complex in structure and cannot operate stably.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of robots, in particular to a reconfigurable amphibious robot. BACKGROUND

[0002] A robot is an intelligent machine capable of semi-autonomous or autonomous work, which can perform tasks such as work or movement through programming and automatic control; among them, with the rapid development of high-altitude work and the increasing demand, the importance of unmanned aerial vehicle robots is increasing, and with the rapid development of science and technology, unmanned aerial vehicle technology has been widely used in military, civilian and scientific research fields. However, the existing unmanned aerial vehicles are mainly designed for specific environments, such as aerial unmanned aerial vehicles and underwater unmanned aerial vehicles. Although aerial and underwater unmanned aerial vehicle technology is quite mature, unmanned aerial vehicles that can operate in both land and air environments are still a research blank. Therefore, amphibious unmanned aerial vehicles have emerged to fill this technical gap.

[0003] Amphibious unmanned aerial vehicles, as the name implies, can operate in both land and air environments. Such unmanned aerial vehicles can perform tasks such as reconnaissance, surveillance, target positioning and communication relay in complex battlefield environments such as mountains, forests and deserts. Amphibious robots combine the characteristics of aerial vehicles and ground mobile robots, and can fly in the air and move on the ground. This feature makes amphibious robots have broad application prospects in many fields. For example, in the fields of disaster rescue, wildlife research and topographic survey, amphibious unmanned aerial vehicles also have broad application prospects. In the search and rescue work at disaster sites, amphibious robots can quickly reach the disaster area to provide necessary information for rescue personnel and improve rescue efficiency. In addition, amphibious robots also have great application potential in the fields of environmental monitoring, agriculture and logistics.

[0004] At present, amphibious unmanned aerial vehicles are mainly of two types: fixed-wing amphibious unmanned aerial vehicles and deformable amphibious unmanned aerial vehicles; among them, the flight part and the walking part of the fixed-wing amphibious unmanned aerial vehicle are fixedly arranged at the top and bottom of the unmanned aerial vehicle body respectively to achieve the purpose of amphibiousness, but the fixedly arranged walking part is generally only suitable for flat straight sections, resulting in that when crossing complex terrain such as hills and depressions, the unmanned aerial vehicle still needs to rely on the flight part, thereby making the energy consumption of the unmanned aerial vehicle high, and further affecting the overall endurance.

[0005] Although the deformable amphibious unmanned aerial vehicle can adopt a deformation structure to control the rotation angle of the flight structure or the walking structure, thereby switching the working mode of the unmanned aerial vehicle, the traditional unmanned aerial vehicle only deforms the flight structure or the walking structure, thereby resulting in a complex overall structure of the unmanned aerial vehicle.

[0006] The Chinese patent with the publication number CN220410908U discloses a deformable amphibious robot, which realizes posture adjustment of the robot by changing the thrust direction of the paddle. On the one hand, the walking wheels of the robot are passively driven, resulting in poor braking capability of the robot. On the other hand, the walking and flying still rely on two structures, resulting in high space occupancy rate between the two structures and large overall volume of the robot.

[0007] Therefore, we provide a robot with simple structure and stable walking and flying actions. SUMMARY

[0008] The present application aims to provide a reconfigurable amphibious robot to solve the problems of complex structure and unstable operation of conventional amphibious robots.

[0009] The present application is implemented by the following technical solutions: A reconfigurable amphibious robot, comprising a robot main body, a deformation mechanism and a master control unit installed on the robot main body, and a comprehensive motion mechanism; The deformation mechanism is used to drive the comprehensive motion mechanism to act and switch the operating state of the comprehensive motion mechanism; The operating state of the comprehensive motion mechanism includes a flying mode and a walking mode, and the comprehensive motion mechanism is used to perform flying action in the flying mode and walking action in the walking mode; The master control unit is electrically connected with the deformation mechanism and the comprehensive motion mechanism.

[0010] Further, the deformation mechanism includes four deformation units, and the comprehensive motion mechanism includes four comprehensive motion units, wherein two deformation units are installed on the head end face of the robot main body, and the other two deformation units are installed on the tail end face of the robot main body, and the deformation units on the two end faces of the robot main body are symmetrical, and each deformation mechanism is connected with one comprehensive motion unit.

[0011] Further, the deformation unit includes a rudder disc, wherein the fixed end of the rudder disc is installed in the robot main body, the rotating end of the rudder disc is fixedly connected with the comprehensive motion mechanism, a rudder motor is fixedly installed in the rudder disc, and the drive shaft of the rudder motor is correspondingly and drivingly connected with the rotating end of the rudder disc.

[0012] Further, the rudder disc includes a fixed block, a connecting rod, a positioning ring, and a rotating block, wherein the fixed block is fixedly installed in the robot main body, the fixed block is fixedly connected with the positioning ring through a plurality of connecting rods, and the rotating block is rotatably connected in the positioning ring; one end face of the rotating block is drivingly connected with the drive rod of the rudder motor, and the other end face of the rotating block is fixedly connected with the comprehensive motion mechanism.

[0013] Further, the integrated motion unit comprises a wheel leg, wherein the head end of the wheel leg is connected with the transformation mechanism, a walking motor is fixedly installed in the middle of the wheel leg, and a flight motor is fixedly installed at the tail end of the wheel leg. The shell of the flight motor is rotationally installed with a walking wheel, and the driving shaft of the flight motor is drivingly connected with a paddle. The outer edge surface of the walking wheel is provided with external teeth, and the external teeth are correspondingly meshed with a driving gear installed on the driving shaft of the walking motor.

[0014] Further, the walking wheel comprises an inner ring, an outer ring and a bearing seat, wherein the inner ring and the outer ring are connected through a plurality of supporting rods, the outer edge surface of the inner ring is provided with external teeth, the inner edge surface of the inner ring is fixedly connected with the bearing seat through a plurality of reinforcing rods, and the bearing seat is sleeved on the flight motor.

[0015] Further, the main control unit comprises a sensor assembly, an MCUA, a flight controller, an MCUB and a remote control receiving module, wherein the signal output pins of the MCUA are electrically connected with the flight controller, the MCUB and the transformation mechanism respectively, the control output pin of the flight controller is electrically connected with the flight motor, the attitude information input pin of the flight controller is electrically connected with the sensor assembly, and the control output pin of the MCUB is electrically connected with the walking motor. The signal receiving pin of the MCUA is electrically connected with the remote control receiving module, and the signal receiving pin of the remote control receiving module is signal-connected with a remote controller.

[0016] Further, the sensor assembly comprises an inertial sensor, an air pressure sensor and an optical flow sensor.

[0017] Further, the flight controller adopts a quaternion attitude control solving algorithm to calculate the aerial attitude of the robot body.

[0018] Further, the MCUB and the flight controller both adopt a PID algorithm to control the walking motor and the flight motor.

[0019] The technical scheme of the present application has at least the following advantages and beneficial effects: The present application discloses a reconfigurable amphibious robot, which integrates flight mode and walking mode through an integrated motion mechanism, so that the overall structure of the robot is more compact, thereby reducing the overall volume of the robot. In addition, the transformation mechanism drives the integrated motion mechanism to realize the switching of the running state of the integrated motion mechanism, and also ensures that the walking action and the flying action of the robot are independently performed, so that the walking action and the flying action of the robot are independently performed, avoiding the interference between the two actions, and thereby improving the stability of the robot in operation.

[0020] In addition, the deformation mechanism uses a steering wheel to connect with the integrated motion mechanism, so that the vibration force generated by the integrated motion mechanism during walking can be transferred to the robot body through the steering wheel, reducing the radial force exerted on the servo, thereby improving the overall operation stability of the robot.

[0021] In addition, the travel wheel and the travel motor are connected by gear transmission, and the speed ratio between the drive gear installed on the travel motor and the outer teeth of the travel wheel is 6, so that the drive gear can act as a reduction gear, achieve higher transmission efficiency and reduce energy loss. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] Figure 1 A structural schematic diagram of the present invention; Figure 2 It is a structural schematic diagram of a deformation mechanism of the present invention; Figure 3 This is a structural diagram of a main control unit of the present invention.

[0023] Figure numerals: 1. Robot body; 2. Transformation mechanism; 21. Steering wheel; 211. Fixed block; 212. Connecting rod; 213. Positioning ring; 214. Rotating block; 22. Servo; 3. Integrated motion mechanism; 31. Wheel leg; 32. Walking motor; 33. Flight motor; 34. Walking wheel; 341. Inner ring; 342. Outer ring; 343. Support rod; 344. Reinforcement rod; 345. Bearing seat; 35. Blade; 36. External tooth; 37. Drive gear; 4. Main control unit; 41. Sensor assembly; 42. MCUA; 43. Flight controller; 44. MCUB; 45. Remote control receiving module. DETAILED DESCRIPTION

[0024] To make the objectives, technical solutions, and advantages of the embodiments of the present invention more clear, the technical solutions of the embodiments of the present invention will be clearly and completely described below in conjunction with the accompanying drawings of the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Generally, the components of the embodiments of the present invention described and shown in the drawings herein can be arranged and designed in various different configurations.

[0025] Example 1 like Figures 1-2 The reconfigurable air-land amphibious robot shown includes a robot body 1, a deformation mechanism 2 and a main control unit 4 mounted on the robot body 1, and an integrated motion mechanism 3; The deformation mechanism 2 is used to drive the integrated motion mechanism 3 to move and switch the operating state of the integrated motion mechanism 3; According to the needs, the deformation mechanism 2 comprises four deformation units, and the comprehensive motion mechanism 3 comprises four comprehensive motion units, wherein two deformation units are installed on the head end surface of the robot body 1, the other two deformation units are installed on the tail end surface of the robot body 1, and the deformation units on the two end surfaces of the robot body 1 are symmetrical, each deformation mechanism 2 is connected with one comprehensive motion unit; That is, the four deformation units and the four comprehensive motion units are in a symmetrical state, which ensures that the center of gravity of the robot as a whole can be located at the relative center of the robot, so that the flight action of the robot is more stable; it should be noted that the four deformation units and the four comprehensive motion units are independent actions; In addition, the deformation unit comprises a steering wheel 21, wherein the fixed end of the steering wheel 21 is installed in the robot body 1, the rotating end of the steering wheel 21 is fixedly connected with the comprehensive motion mechanism 3, and the steering engine 22 is fixedly installed in the steering wheel 21, and the driving shaft of the steering engine 22 is drivingly connected with the rotating end of the steering wheel 21; In addition, the steering wheel 21 comprises a fixed block 211, a connecting rod 212, a positioning ring 213 and a rotating block 214, wherein the fixed block 211 is fixedly installed in the robot body 1, the fixed block 211 is fixedly connected with the positioning ring 213 through a plurality of connecting rods 212, and the rotating block 214 is rotatably connected in the positioning ring 213; one end surface of the rotating block 214 is drivingly connected with the driving rod of the steering engine 22, and the other end surface of the rotating block 214 is fixedly connected with the comprehensive motion mechanism 3; It should be noted that the cross section of the rotating block 214 is circular, and the rotating block 214 is connected with the inner ring of the positioning ring 213 through a bearing; In the deformation mechanism 2 and the comprehensive motion mechanism, the steering engine 22 is a driving part, the comprehensive motion mechanism is a passive part, and the steering wheel 21 is an intermediate connecting part therebetween, the driving connection between the deformation mechanism 2 and the comprehensive motion mechanism is realized through the connecting block of the steering wheel 21, and on the other hand, when the comprehensive motion mechanism enters the walking mode and walks on the bottom surface, due to the flatness of the ground and other conditions, the comprehensive motion mechanism will generate a large vibration when walking, which will be directly transmitted to the deformation mechanism 2, and the steering wheel 21 transmits the vibration force to the robot body 1 to share, thereby reducing the impact of the vibration force on the steering engine 22 and reducing the damage to the deformation mechanism 2, thereby effectively solving the problems of loose connection between the output shaft of the steering engine 22 and the wheel leg 31 in the comprehensive motion mechanism and large vibration amplitude, and significantly improving the stability and durability of the robot in complex terrain.

[0026] The running state of the comprehensive motion mechanism 3 comprises a flight mode and a walking mode, and the comprehensive motion mechanism 3 is used for executing a flight action in the flight mode and executing a walking action in the walking mode; That is, the walking action and the flying action are independently performed without interference between each other, ensuring that both actions can be stably performed; The integrated movement unit comprises a wheel leg 31, wherein the head end of the wheel leg 31 is connected with the transformation mechanism 2, a walking motor 32 is fixedly installed in the middle of the wheel leg 31, and a flying motor 33 is fixedly installed at the tail end of the wheel leg 31; A walking wheel 34 is rotatably installed on the shell of the flying motor 33, and the driving shaft of the flying motor 33 is drivingly connected with a paddle 35; The outer edge surface of the walking wheel 34 is provided with an outer tooth 36, which is correspondingly engaged with a driving gear 37 installed on the driving shaft of the walking motor 32; That is, the rotation planes of the wheel leg 31 and the paddle 35 and the rotation plane of the walking wheel 34 are correspondingly parallel, and the wheel leg 31 and the driving shafts of the walking motor 32 and the flying motor 33 are correspondingly perpendicular, so that the switching of the movement state of the robot can be realized by changing the angle of the wheel leg 31 through the transformation mechanism 2, i.e., the rudder disc 21 and the rudder 22. It should be noted that, Figure 1 The robot shown is in the walking mode, and after the transformation mechanism 2 drives the wheel leg 31 to rotate by 90°, the wheel legs 31 located on the same end surface will be respectively directed to different sides of the robot body 1, and the robot body 1 is switched from the walking mode to the flying mode; It should be noted that the rotation angle of the wheel leg 31 is: perpendicular to the bottom surface of the robot body, defined as 0°, to correspondingly parallel to the bottom surface of the robot body, defined as 90°; and if the rotation angle of the wheel leg 31 is less than 90°, the flying motor 33 can also be started, which is called "inclined flying". It can help the robot to change direction or turn more quickly in flight, and the inclined flying can be realized by adjusting the attitude controller of the robot, so that the rotor is inclined inward, thereby generating a lateral thrust to help the robot change direction. This flying mode is usually used in situations where quick turning or obstacle avoidance is required, which improves the mobility and flexibility of the robot. The robot's center of gravity can also be changed by this method to increase the inertia of the robot, thereby increasing the robot's resistance to air flow disturbance. In particular, the paddle 35 is a scimitar paddle; In addition, the walking wheel 34 comprises an inner ring 341, an outer ring 342 and a bearing seat 345, wherein the inner ring 341 and the outer ring 342 are connected by a plurality of supporting rods 343, the outer edge surface of the inner ring 341 is provided with an outer tooth 36, the inner edge surface of the inner ring 341 is fixedly connected with the bearing seat 345 through a plurality of reinforcing rods 344, and the bearing seat 345 is sleeved on the flying motor 33; Wherein, the number of teeth of the drive gear 37 and the outer teeth 36 are 23 and 138 respectively, and the two combined constitute a reduction gear structure, and the reduction ratio of the two is 1 / 6, the walking motor 32 adopts a large torque motor, namely M2006 motor, and according to the specification parameters of the M2006 motor, the continuous torque of the M2006 motor is 1 , the torque will be amplified by 6 times after the reduction gear set, so for the whole robot, the actual torque of each wheel train will be amplified to 6 . Through subsequent physical measurement, the weight of the whole robot is 4.8kg, so the M2006 motor can ensure the normal operation of the robot in land mode; In addition, the use of reduction gear structure also saves installation space. Due to the meshing of multiple gears, the motion of gear transmission is more stable, and the ability to resist impact and vibration is stronger, improving the reliability of transmission. The reduction gear can withstand a large load and is suitable for heavy or high load occasions. Under correct use and maintenance, the reduction gear can achieve high transmission efficiency and reduce energy loss. However, there are also some problems in the use of reduction gear set. For example: the reduction gear may produce a lot of noise during operation, especially at high speed or under heavy load, which affects the working environment and the comfort of the user. High-precision and high-quality reduction gears have high manufacturing costs, especially in cases involving special materials or complex processes, so the reduction gear needs regular maintenance, including lubricating oil replacement, gear wear inspection, etc., to ensure its normal work and prolong its service life.

[0027] The main control unit 4 is electrically connected with the transformation mechanism 2 and the comprehensive motion mechanism 3, and the control of the transformation mechanism 2 and the comprehensive motion mechanism 3 is completed through the main control unit 4, that is, the walking action and flying action of the amphibious robot are realized, and the switching between the two motion states is realized.

[0028] Embodiment 2 As shown in Figure 3 As an embodiment, the main control unit 4 includes a sensor assembly 41, an MCUA 42, a flight controller 43, an MCUB 44, and a remote control receiving module 45, wherein the signal output pins of the MCUA 42 are electrically connected with the flight controller 43, the MCUB 44, and the transformation mechanism 2 respectively, the control output pin of the flight controller 43 is electrically connected with the flight motor 33, the attitude information input pin of the flight controller 43 is electrically connected with the sensor assembly 41, and the control output pin of the MCUB 44 is electrically connected with the walking motor 32; The signal receiving pin of the MCUA 42 is electrically connected with the remote control receiving module 45, and the signal receiving pin of the remote control receiving module 45 is connected with the remote controller signal; The MCUA 42 receives the action instruction in the walking mode, and then transmits the action instruction to the MCUA 42. The MCUA 42 calculates according to the PID algorithm written in the internal, obtains the proportional output signal, and then controls the action of the walking motor 32. The MCUA 42 receives the action instruction in the walking mode, and then transmits the action instruction to the MCUA 42. The MCUA 42 calculates according to the PID algorithm written in the internal, obtains the proportional output signal, and then controls the action of the walking motor 32. The PID control formula is:

[0029] Among them: The proportional gain is Kp, The integral time constant is Ki, The derivative time constant is Kd, The output signal of the PID controller is Y, The given value is R The difference between the measured value and the given value is e; These parameters can be flexibly set according to specific application scenarios and requirements to achieve the best control performance. In addition, the PID algorithm can also be combined with other control algorithms to form a composite control strategy to further improve the control effect. PID algorithm is widely used in various industrial control fields, such as temperature control, speed control, position control, etc. In the motion control of amphibious robots, the PID algorithm also performs well, which can effectively realize the precise motion control and attitude stability of the robot.

[0030] The MCUA 42 receives the action instruction in the walking mode, and then transmits the action instruction to the MCUA 42. The MCUA 42 calculates according to the PID algorithm written in the internal, obtains the proportional output signal, and then controls the action of the walking motor 32. Due to the unique advantages of quaternions in three-dimensional rotation representation, it can avoid the gimbal lock problem in Euler angle representation, while maintaining the stability and efficiency of calculation.

[0031] Therefore in the attitude control solution, usually use quaternion to express the attitude of the object. The attitude of the object can be understood as the direction and position of the object in three-dimensional space. For dynamic systems such as amphibious robots, we need to update its attitude information in real time to ensure that it can accurately perform tasks. In addition to the quaternion attitude control solution, there is also a sliding membrane backstepping method combined with a hybrid filtering algorithm to resist disturbances such as self-shaking, wind speed, and uneven mass of the cantilever. The process of the quaternion attitude control solution algorithm is as follows: there is a quaternion:

[0032] wherein the quaternion Q is a variable, and , is the real part, and the rest is the imaginary part, is the instantaneous rotation axis of the rigid body, and is the angle, where the superscript e represents the geographical coordinate system of the earth.

[0033] After time differentiation:

[0034] and the angular velocity vector , represents the angular velocity in the body coordinate system, and the above formula can be obtained after rearrangement:

[0035] wherein is the skew-symmetric matrix composed of angular velocity: ; and then use the first-order Runge-Kutta method:

[0036] wherein, is the time step, is the current quaternion attitude; Finally, the quaternion attitude solution algorithm is:

[0037] When using quaternion for unmanned aerial vehicle attitude solution, the angular velocity data and aircraft height of the object need to be obtained through inertial sensors, optical flow sensors, etc. These data describe the rotational speed, direction height of the object in three-dimensional space. Using the obtained angular velocity data and time interval, the quaternion attitude of the object is updated through the differential equation of quaternion or the Runge-Kutta formula, etc. As shown in the above formula. The updated quaternion is converted into Euler angles or other representations to understand the current attitude of the object more intuitively. According to the updated attitude information and the target attitude, a suitable control algorithm is designed to adjust the attitude of the object. In this research, the PID control method is used to ensure that the object can stably reach the target attitude.

[0038] In summary, the quaternion attitude control solution combined with other auxiliary algorithms is an effective attitude updating and control method, which is suitable for attitude control tasks of complex systems such as amphibious robots. Through reasonable algorithm design and optimization, accurate control and stable motion of objects in three-dimensional space can be realized.

[0039] Although the quaternion attitude control solution process is simple and efficient, it may be affected by the information collected by the sensor in the environment, and then cause the error of the attitude. Therefore, it is still necessary to combine the filtering algorithm to reduce the error and improve the accuracy and stability of the attitude estimation. In order to obtain more accurate data to provide accurate control, Kalman filtering is adopted for iterative update in the practice process, that is, the data obtained by the sensor component 41 is first updated by Kalman filtering, and then calculated by the quaternion attitude control solution algorithm.

[0040] Based on the linear system state equation, the optimal estimation of the system state is performed through the processing of the observation data of the system input and output. Its main goal is to remove noise and restore the true data. Kalman filtering does not require the assumption that the signal and noise are stationary processes. As long as some appropriate assumptions are made on the statistical properties of system disturbances and observation errors, it can obtain the minimum error estimation value of the true signal in the average sense.

[0041] Specifically, the working principle of Kalman filtering can be divided into two main steps: prediction and update. In the prediction step, the filter uses the dynamic model of the system to predict the next state (i.e., the state at the next time step). This usually involves calculating the predicted value of the state based on the current state estimate and the control input of the system. Then, in the update step, the filter uses the observation data to update its state estimate. This involves calculating the difference (or residual) between the predicted state and the observed state, and how this difference affects the update of the state estimate. The time update equation and the state update equation in discrete time are as follows: Time update equation:

[0042] State update equation:

[0043] where A is the state transformation matrix acting on the state vector ; B is the input control matrix acting on the input vector ; x is the prior state estimate at time step ; z is the observation at time step where x is the state vector, x is the prior state estimate, P is the prior state estimate error covariance matrix, H is the observation model matrix that converts the true state space to the observation space, y is the observation vector, and R is the process noise covariance matrix. is the prior estimate error covariance matrix. is the posterior estimate error covariance matrix; Q is the process noise covariance matrix; R is the process noise covariance matrix; and I is the identity matrix. is the Kalman gain or mixing factor.

[0044] A key advantage of using a Kalman filter is that it only needs to store the estimated value of the previous state, rather than storing all past observation data. This makes the Kalman filter computationally efficient and suitable for real-time systems. In addition, due to its recursive nature, the Kalman filter can easily handle changes in dynamic systems.

[0045] In summary, the working principle of Kalman filtering is based on linear system state equations and recursive estimation, which realizes the optimal estimation of dynamic systems through prediction and update of system states.

[0046] In particular, the sensor assembly 41 includes an inertial sensor, an air pressure sensor, and an optical flow sensor, The air pressure sensor is a key sensor in the aircraft for measuring atmospheric pressure and altitude, which can measure atmospheric pressure and transmit the obtained value to the built-in ADC of the flight control, and then convert it to the altitude at the current atmospheric pressure through the program. Since atmospheric pressure is inversely proportional to altitude, the barometer can accurately obtain the altitude value by comparing the measured atmospheric pressure value with the standard atmospheric pressure. At the same time, in order to meet the needs of small multi-rotor aircraft and other aircraft, the barometer often has a small package size, which is convenient for integration in the circuit board of the flight control. The barometer has fast response speed and can provide relatively accurate altitude information, which is crucial for the flight control and autonomous landing of the aircraft. However, its work is affected by weather, environment, and other factors, and humid or sultry weather can cause a large fluctuation in atmospheric pressure. Moreover, it is easily affected by external factors such as vibration and pressure, which can cause measurement errors. Some high-performance barometers, such as the SPL06 model integrated in the flight control used in this case, have higher air pressure accuracy and sensitivity, which can significantly improve the air pressure height determination effect of the flight control.

[0047] The inertial sensor adopts BMI088 model, which is the most commonly used sensor in the process of detecting and adjusting the attitude of the unmanned aerial vehicle. During the debugging process, the calibration and configuration of the IMU are mainly involved, and the debugging condition directly affects whether the flight control allows the unmanned aerial vehicle to be unlocked for takeoff, and the accuracy of the calibration directly affects the flight state of the unmanned aerial vehicle. The calibration of the IMU is very important because it can ensure that the data provided by the IMU sensor is accurate. The calibration process is to transmit the data measured by the unmanned aerial vehicle flight control integrated sensor to the anonymous host computer through the data link, then place the unmanned aerial vehicle on a stable horizontal surface, and then follow the prompt of the anonymous host computer to operate until the sensor is reminded by the anonymous host computer that the calibration is completed. The process is to place the unmanned aerial vehicle in different directions or angles for calibration to ensure that all sensors can work normally; In addition, the sampling rate, filtering method and other parameters of the IMU are set to meet the specific flight requirements. The setting of these parameters will directly affect the accuracy and response speed of the IMU data, so it needs to be adjusted according to the actual situation; Finally, attention should also be paid to the installation position and orientation of the flight control. The flight control should be installed at the center of the unmanned aerial vehicle to ensure that the initial position of the flight control is in the most accurate position and a shock-absorbing base is properly installed to reduce errors caused by vibration or rotation. At the same time, the orientation of the flight control also needs to be consistent with the coordinate system of the unmanned aerial vehicle to ensure the correctness of the data; During flight, the flight control system will calculate the attitude, speed and other information of the unmanned aerial vehicle based on the data provided by the IMU sensor, so as to realize accurate control of the unmanned aerial vehicle. Therefore, maintaining the good working state of the IMU is crucial for the stable flight of the unmanned aerial vehicle.

[0048] The optical flow sensor is an anonymous scientific and technological light flow module. The optical flow sensor can communicate with the host computer through high-speed radio data transmission, read the information collected by the optical flow, and complete the calibration and configuration of the corresponding parameters through the host computer. With the host computer, three kinds of optical flow data can be selected for output. The first is the original optical flow data, which is not processed and directly outputs the visual data of the optical flow sensor. The second is the decoupled optical flow data, which indicates the ground speed after decoupling. The third is the fusion data, which indicates a more accurate ground speed and is more suitable for aircraft control, saving the user's development difficulty of decoupling. The frequency of the first two is fixed at 50hz, and the frequency of the third can be adjusted. In addition to the three modes, the host computer can also complete the parameter fusion operation, adjust the fusion ratio, and the larger the parameter, the faster the original data is followed, and the larger the noise is.

[0049] In the theory of optical flow, it is assumed that the pixel gray scale between the two images collected by the camera is constant and the adjacent two pixels have relative motion. When the gray scale of the two frames is constant, then:

[0050] wherein represents the initial position luminance, represents the position luminance after moving to the second frame image, and is obtained after using Taylor expansion:

[0051] The above formula is an optical flow equation, wherein and represents the gradient of the image, represents the time gradient. After the second assumption is established, the LK algorithm is used based on the assumption, and finally the least square method is used for fitting solution, and finally as shown in the following formula:

[0052] The above formula is a method for calculating the moving speed of a pixel point by using the optical flow method. When used, some points in the image are tracked. The data collected by the optical flow inside the flight control is calculated by using the above method to obtain the optical flow vector. According to the obtained optical flow vector, the attitude control of the unmanned aerial vehicle is optimized, and more accurate control is realized. In addition, the optical flow sensor uses a laser TOF ranging method, which can avoid the interference of aircraft noise and airflow.

[0053] The above only for the preferred embodiments of the present application, and is not intended to limit the present application, for those skilled in the art, the present application can have various changes and variations. Any modification, equivalent replacement, improvement, etc. made within the spirit and principles of the present application shall be included in the protection scope of the present application.

Claims

1. A reconfigurable air-land amphibious robot, characterized in that: It includes a robot body (1), a deformation mechanism (2) and a main control unit (4) installed on the robot body (1), and an integrated motion mechanism (3); The deformation mechanism (2) is used to drive the integrated motion mechanism (3) to move, and then switch the operating state of the integrated motion mechanism (3); The operating states of the integrated motion mechanism (3) include a flight mode and a walking mode, and the integrated motion mechanism (3) is used to perform a flying action in the flight mode and to perform a walking action in the walking mode; The main control unit (4) is electrically connected to the deformation mechanism (2) and the integrated motion mechanism (3).

2. The reconfigurable amphibious robot according to claim 1, characterized in that: The deformation mechanism (2) includes four deformation units, and the integrated motion mechanism (3) includes four integrated motion units, wherein two deformation units are installed on the head end face of the robot body (1), and the other two deformation units are installed on the tail end face of the robot body (1), and the deformation units on the two end faces of the robot body (1) are symmetrical, and each deformation mechanism (2) is connected to a corresponding integrated motion unit.

3. The reconfigurable amphibious robot according to claim 1, characterized in that: The deformation unit comprises a steering wheel (21), wherein a fixed end of the steering wheel (21) is installed in the robot body (1), a rotating end of the steering wheel (21) is fixedly connected to the integrated motion mechanism (3), a steering gear (22) is fixedly installed in the steering wheel (21), and a drive shaft of the steering gear (22) is correspondingly driven and connected to the rotating end of the steering wheel (21).

4. The reconfigurable amphibious robot according to claim 3, characterized in that: The steering wheel (21) comprises a fixed block (211), a connecting rod (212), a positioning ring (213) and a rotating block (214), wherein the fixed block (211) is fixedly installed in the robot body (1), the fixed block (211) is fixedly connected to the positioning ring (213) through a plurality of connecting rods (212), and the rotating block (214) is rotatably connected in the positioning ring (213); one end face of the rotating block (214) is drivingly connected to the driving rod of the steering gear (22), and the other end face of the rotating block (214) is fixedly connected to the integrated motion mechanism (3).

5. The reconfigurable amphibious robot according to claim 1, characterized in that: The integrated motion unit comprises a wheel leg (31), wherein the head end of the wheel leg (31) is correspondingly connected to the deformation mechanism (2), a walking motor (32) is fixedly installed in the middle of the wheel leg (31), and a flight motor (33) is fixedly installed at the end of the wheel leg (31); A running wheel (34) is rotatably mounted on the housing of the flight motor (33), and a driving shaft of the flight motor (33) is drivingly connected to the blade (35); The outer edge surface of the travel wheel (34) is provided with external teeth (36), and the external teeth (36) are correspondingly meshed with a driving gear (37) installed on the driving shaft of the travel motor (32).

6. The reconfigurable amphibious robot according to claim 5, characterized in that: The walking wheel (34) includes an inner ring (341), an outer ring (342) and a bearing seat (345), wherein the inner ring (341) and the outer ring (342) are connected by a plurality of support rods (343), the outer edge surface of the inner ring (341) is provided with external teeth (36), and the inner edge surface of the inner ring (341) is fixedly connected to the bearing seat (345) through a plurality of reinforcing rods (344), and the bearing seat (345) is sleeved on the flight motor (33).

7. The reconfigurable amphibious robot according to any one of claims 1 to 6, characterized in that: The main control unit (4) includes a sensor assembly (41), an MCUA (42), a flight controller (43), an MCUB (44) and a remote control receiving module (45), wherein the signal output pin of the MCUA (42) is electrically connected to the flight controller (43), the MCUB (44) and the deformation mechanism (2), respectively; the control output pin of the flight controller (43) is electrically connected to the flight motor (33); the attitude information input pin of the flight controller (43) is electrically connected to the sensor assembly (41); and the control output pin of the MCUB (44) is electrically connected to the walking motor (32); The signal receiving pin of the MCUA (42) is electrically connected to the remote control receiving module (45), and the signal receiving pin of the remote control receiving module (45) is connected to the remote control signal.

8. The reconfigurable amphibious robot according to claim 7, characterized in that: The sensor assembly (41) includes an inertial sensor, an air pressure sensor, and an optical flow sensor.

9. The reconfigurable amphibious robot according to claim 7, characterized in that: The flight controller (43) uses a quaternion attitude control solution algorithm to calculate the aerial attitude of the robot body.

10. The reconfigurable amphibious robot according to claim 7, characterized in that: The MCUB (44) and the flight controller (43) both use a PID algorithm to control the walking motor (32) and the flight motor (33).

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