Small airship device and control method for automatic modeling of indoor three-dimensional objects

Abstract

The application discloses a small airship device and a control method for automatic modeling of indoor three-dimensional objects, and belongs to the field of indoor aircraft intelligent inspection and three-dimensional perception systems. The airship adopts a four-rotor design arranged in layers. The upper vertical rotors control horizontal forward and backward movement and turning, and the lower horizontal rotors adjust the lifting force to realize lifting and hovering, thereby realizing multi-degree-of-freedom decoupling control. Attitude data are collected through an attitude sensor, and a PID algorithm is combined to realize automatic height maintenance. A communication module is used to build a WiFi local area network and run a Web control page, thereby realizing remote flight control of an intelligent terminal. On this basis, a preset flying-around program is executed to control the airship to automatically cruise at a constant radius and height around a target object, the rudders are synchronously adjusted to drive the camera to take multi-angle photographs, and image acquisition required for three-dimensional modeling is completed. The method combines manual and automatic control modes, and improves flight stability and modeling efficiency.

Description

Technical Field

[0001] This invention relates to the field of intelligent inspection and three-dimensional perception system technology for indoor aircraft, and particularly to a small airship device and control method for automatic modeling of indoor three-dimensional objects. Background Technology

[0002] As an important branch of low-altitude aircraft, airships are widely used in surveying, security, archaeology, and indoor space digitization. With the development of low-altitude economy and 3D modeling technology, micro-sized soft airships, due to their advantages such as long endurance, low noise, and high safety, are gradually becoming a potential alternative to traditional drones in complex indoor environments. Among related technologies, an airship platform with multi-degree-of-freedom motion capabilities has been constructed through the collaborative operation of a rotor propulsion system, attitude sensors, and wireless communication modules. Specifically, this technology system covers the entire process from aerodynamic design and power system integration to control algorithm development, including key aspects such as airbag structure, motor layout, sensor selection, and communication protocols. In recent years, solutions such as tri-rotor layouts, vector propulsion, and flapping-wing airships have been proposed to improve the maneuverability and control accuracy of airships; however, these are still largely in the laboratory research stage and have not yet formed a systematic design for specific application scenarios.

[0003] However, existing airship technologies directly employ flexible connections between the pod and the multi-rotor propulsion system without co-optimizing the structure and control for 3D modeling tasks. This can lead to problems such as insufficient motion stability, high control complexity, and low modeling efficiency. Specifically, most solutions rely on Bluetooth or infrared communication modules, which have limited transmission distances and poor scalability, making it difficult to meet the remote control requirements for large-scale spatial modeling. Meanwhile, vector propulsion or flapping-wing control schemes require high algorithm robustness and incur high debugging costs, hindering rapid deployment and engineering applications. Furthermore, existing technologies lack clear application scenario guidance, resulting in redundant hardware configurations and functional disconnects, making it difficult to play an effective role in practical needs such as archaeology and cave mapping, thus affecting their practical value and potential for widespread application in specific fields. Summary of the Invention

[0004] The present invention aims to at least partially solve one of the technical problems in the related art.

[0005] This invention proposes a small airship device for automatic modeling of indoor three-dimensional objects.

[0006] Another objective of this invention is to propose an airship control method for automatic modeling of indoor three-dimensional objects.

[0007] To achieve the above objectives, this invention proposes a small airship device for automatic modeling of indoor 3D objects, comprising: an external aerodynamic structure and an internal control system, wherein...

[0008] The external aerodynamic structure includes a near-spherical soft aluminum membrane airbag; a multi-layer detachable rigid pod support fixed below the airbag; the support includes a four-layer structure, the first layer for fixing the main control board, with cantilever arms at both ends for mounting the horizontal propulsion rotor; the second layer for fixing the wireless communication module, with cantilever arms at both ends for mounting the vertical lift rotor; the third layer for fixing the power module; and the fourth layer for fixing the servo motor and camera.

[0009] The internal control system uses an Arduino Uno development board as its core control unit, and includes a power system, an automatic control system, a WiFi communication system, and an image acquisition system; wherein:

[0010] The power system includes at least two XY-2.5AD motor control modules and four coreless motors. The motor control modules are connected to the Arduino Uno development board and receive PWM control signals to drive the horizontal propulsion and vertical lift rotors, respectively.

[0011] The automatic control system includes an MPU6050 attitude sensor connected to the Arduino Uno development board, which is used to collect the airship's three-axis acceleration and attitude angle to realize closed-loop control of flight attitude.

[0012] The WiFi communication system includes an ESP8266 communication module connected to the Arduino Uno development board via a serial port, used to establish a WiFi local area network and receive remote control commands from smart terminals.

[0013] The image acquisition system includes a servo motor connected to the Arduino Uno development board and an integrated image transmission camera fixed on the servo motor, which wirelessly transmits the images to a ground terminal.

[0014] The small airship device for automatic modeling of indoor three-dimensional objects according to embodiments of the present invention may also have the following additional technical features:

[0015] In one embodiment of the present invention, the power system includes a lithium battery, four coreless motors, four micro rotors driven by the coreless motors, and two XY-2.5AD motor control modules. The lithium battery powers the motor control modules, which drive the two sets of coreless motors to adjust their speed and direction based on PWM control signals from the Arduino Uno development board. Two motors drive rotors with horizontal rotating surfaces to adjust the airship's lift, while the other two motors drive rotors with vertical rotating surfaces to provide horizontal thrust. The two sets of rotors are arranged in a layered axisymmetric configuration, with the lift rotor located in the lower layer and the thrust rotor in the upper layer to avoid wake interference. The two sets of motors are powered and controlled independently to achieve decoupled adjustment of lift and thrust.

[0016] In one embodiment of the present invention, the automatic control system includes an MPU6050 attitude sensor, the MPU6050 attitude sensor via... The interface is connected to the Arduino Uno development board for real-time acquisition of the airship's three-axis acceleration and attitude angle data. The Arduino Uno development board generates PWM control signals by running a preset adjustment program based on the received sensor data, and adjusts the motors of the power system to achieve closed-loop control of the airship's flight attitude.

[0017] In one embodiment of the present invention, the WiFi communication system includes an ESP8266 communication module. The ESP8266 communication module is connected to the Arduino Uno development board through a serial communication interface and is configured to establish a local WiFi area network and receive wireless control commands from a smart terminal. After parsing the commands, the module transmits them to the Arduino Uno development board in the form of digital signals, thereby realizing remote control of the power system, automatic control system and other functional modules.

[0018] In one embodiment of the present invention, the image acquisition and processing system includes a servo motor and a miniature camera. The servo motor is connected to the PWM control pin of the Arduino Uno development board and is controlled by remote commands to adjust the shooting angle. The miniature camera is fixed to the output end of the servo motor and rotates with the servo motor to achieve omnidirectional shooting. The camera is an integrated image transmission camera with wireless image transmission function. Alternatively, the camera is connected to a WiFi network through an ESP8266 communication module to achieve remote camera control based on wireless signals.

[0019] To achieve the above objectives, another aspect of the present invention proposes an airship control method for automatic modeling of indoor 3D objects, comprising:

[0020] S1 establishes the basic motion control logic for the airship. PWM control signals are output through the Arduino Uno development board to drive two sets of hollow cup motors. Specifically, the rotor speed and direction of the two upper vertical rotating surfaces are controlled to achieve forward, backward, left, and right turns of the airship. The rotor speed of the two lower horizontal rotating surfaces is controlled to achieve ascent, descent, and hovering of the airship. The four rotors are arranged in layers, with independent power supply and control, avoiding airflow interference and completing the decoupled control of the airship's multi-degree-of-freedom motion.

[0021] S2 constructs a WiFi-based remote manual control mechanism. It establishes a local wireless LAN through the ESP8266 communication module and runs an embedded web server to provide a graphical user interface. After the smart terminal connects to the network, it sends flight commands through a webpage. The ESP8266 receives and forwards the commands to the Arduino Uno development board, triggering the corresponding basic motion control program to achieve human-machine interactive manual control.

[0022] S3 enables closed-loop automatic altitude maintenance. It uses the MPU6050 attitude sensor to collect the airship's three-axis acceleration and attitude angle data in real time and transmits them to the Arduino Uno development board. The PID control algorithm is used to process the sensor data and dynamically adjust the PWM output of the lower-level lift rotor to keep the airship stable within the set altitude range and suppress vertical disturbances.

[0023] S4 executes the automatic flight modeling control program, calls the preset circular or spiral flight path algorithm, and controls the upper propulsion rotor to run at a set speed and radius while maintaining altitude, driving the airship to fly horizontally around the target object; at the same time, the camera pitch angle is adjusted by the servo motor to realize continuous acquisition of multi-view images and complete the data acquisition before 3D modeling.

[0024] The miniature airship device and control method for automatic modeling of indoor three-dimensional objects according to embodiments of the present invention can realize a micro-miniature airship platform with simple structure and stable control, effectively improving the efficiency and accuracy of automatic modeling of indoor three-dimensional objects or spaces.

[0025] Additional aspects and advantages of the invention will be set forth in part in the description which follows, and in part will be obvious from the description, or may be learned by practice of the invention. Attached Figure Description

[0026] The above and / or additional aspects and advantages of the present invention will become apparent and readily understood from the following description of the embodiments taken in conjunction with the accompanying drawings, wherein:

[0027] Figure 1 This is a structural diagram of a small airship device for automatic modeling of indoor three-dimensional objects according to an embodiment of the present invention;

[0028] Figure 2 This is a schematic diagram of the pod design according to an embodiment of the present invention;

[0029] Figure 3 This is a schematic diagram of the airship control system structure according to an embodiment of the present invention;

[0030] Figure 4 This is a schematic diagram of a three-dimensional modeled airship flying around a target, according to an embodiment of the present invention.

[0031] Figure 5 This is a flowchart of an airship control method for automatic modeling of indoor three-dimensional objects according to an embodiment of the present invention. Detailed Implementation

[0032] It should be noted that, unless otherwise specified, the embodiments and features described in the present invention can be combined with each other. The present invention will now be described in detail with reference to the accompanying drawings and embodiments.

[0033] To enable those skilled in the art to better understand the present invention, the technical solutions of the present invention will be clearly and completely described below with reference to the accompanying drawings of the embodiments of the present invention. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort should fall within the scope of protection of the present invention.

[0034] The following description, with reference to the accompanying drawings, describes a small airship device and control method for automatic modeling of indoor three-dimensional objects according to an embodiment of the present invention.

[0035] Example 1

[0036] The small airship device for automatic modeling of indoor 3D objects according to embodiments of the present invention, such as Figure 1 As shown, it includes: an external aerodynamic structure and an internal control system, wherein,

[0037] The external aerodynamic structure includes a near-spherical soft aluminum membrane airbag; a multi-layer detachable rigid pod support fixed below the airbag; the support includes a four-layer structure, the first layer for fixing the main control board, with cantilever arms at both ends for mounting the horizontal propulsion rotor; the second layer for fixing the wireless communication module, with cantilever arms at both ends for mounting the vertical lift rotor; the third layer for fixing the power module; and the fourth layer for fixing the servo motor and camera.

[0038] The internal control system uses an Arduino Uno development board as its core control unit, and includes a power system, an automatic control system, a WiFi communication system, and an image acquisition system; wherein:

[0039] The power system includes at least two XY-2.5AD motor control modules and four coreless motors. The motor control modules are connected to the Arduino Uno development board and receive PWM control signals to drive the horizontal propulsion and vertical lift rotors, respectively.

[0040] The automatic control system includes an MPU6050 attitude sensor connected to the Arduino Uno development board, which is used to collect the airship's three-axis acceleration and attitude angle to realize closed-loop control of flight attitude.

[0041] The WiFi communication system includes an ESP8266 communication module connected to the Arduino Uno development board via a serial port, used to establish a WiFi local area network and receive remote control commands from smart terminals.

[0042] The image acquisition system includes a servo motor connected to the Arduino Uno development board and an integrated image transmission camera fixed on the servo motor, which wirelessly transmits the images to a ground terminal.

[0043] In one embodiment of the invention, the airship platform uses a near-spherical soft aluminum membrane gasbag as the main gasbag and the primary source of lift for the airship, filled with helium. A multi-layered, detachable pod support structure is designed to reduce weight while effectively securing various components of the control system. The pod and gasbag are rigidly connected without any degrees of freedom of movement. The support structure is divided into four layers: from top to bottom, the first layer secures the Arduino Uno development board, with cantilever arms extending at both ends securing the horizontal propulsion rotor; the second layer secures the ESP8266 communication module, with cantilever arms extending at both ends securing the vertical propulsion rotor; the third layer secures the lithium battery pack; and the fourth layer secures the servo motors and cameras, ensuring unobstructed camera views. Sensors, transformer modules, and other components are rationally fixed within the gaps in the support structure. The power system uses four identical micro-rotors driven by coreless motors. Two rotors have horizontal rotation surfaces, responsible for adjusting the airship's lift, while the other two have vertical rotation surfaces, responsible for providing horizontal propulsion. The two sets of rotors are arranged in a layered, axisymmetrical configuration, with the lift rotor on the lower layer and the propulsion rotor on the upper layer, avoiding wake interference. The two sets of motors are powered and controlled separately. The pod design is as follows: Figure 2 As shown.

[0044] In one embodiment of the present invention, the airship's control system can be divided into four parts: a power system, an automatic control system, a WiFi communication system, and an image acquisition and processing system. The Arduino Uno development board is selected as the computational core of the entire control system.

[0045] The power system consists of an Arduino Uno development board connected to two XY-2.5AD motor control modules. By controlling the output PWM signal of the motor drive module through the change of pin potential difference, the speed and direction of the coreless motor are controlled. The lithium battery powers the motor drive module, which in turn powers the motor, thus achieving power control.

[0046] Specifically, the power system includes a lithium battery, four coreless motors, four micro rotors driven by the coreless motors, and two XY-2.5AD motor control modules. The lithium battery powers the motor control modules, which, based on PWM control signals from the Arduino Uno development board, drive the two sets of coreless motors to adjust their speed and direction. Two motors drive rotors with horizontal rotating surfaces to adjust the airship's lift, while the other two motors drive rotors with vertical rotating surfaces to provide horizontal thrust. The two sets of rotors are arranged in a layered axisymmetric configuration, with the lift rotor on the lower layer and the thrust rotor on the upper layer to avoid wake interference. The two sets of motors are powered and controlled independently, achieving decoupled adjustment of lift and thrust.

[0047] The automatic control system is equipped with an MPU6050 attitude sensor connected to an Arduino Uno development board. This sensor can measure the airship's three-axis acceleration and attitude angle in real time. After the data is returned to the development board, the PWM signal is adjusted through a subsequently written adjustment program to achieve closed-loop control of the airship's power.

[0048] The WiFi communication system utilizes the ESP8266 to establish a WiFi local area network. The ESP8266 integrates functions for establishing a local area network and interacting with smart terminals such as mobile phones. It can receive WiFi signal commands from smart terminals and transmit digital signals to the Arduino Uno development board, thereby enabling remote control of other systems.

[0049] The image acquisition and processing system involves connecting a servo motor to an Arduino Uno development board and mounting a miniature camera on the servo motor. Remote commands can be used to control the servo motor's direction and adjust the camera's shooting angle, enabling omnidirectional image modeling. The current solution uses an integrated image transmission camera, which can directly transmit images wirelessly to a ground base station for viewing on a smart terminal. This solution is simple and convenient, requiring no additional programming. Alternatively, other types of cameras can be used to connect to the ESP8266 communication module and control the camera via WiFi.

[0050] The structure of the airship control system is as follows Figure 3 As shown in Table 1, the specifications of various components are as follows.

[0051] Table 1

[0052]

[0053] Based on the fundamental principle of PWM signal-based motor speed regulation, ten manual control functions were written into the Arduino Uno development board to control the airship's forward, backward, left, right, braking, hovering, and servo steering. Functions directly controlling the airship's motion are implemented by adjusting the speed and direction of each rotor. A signal communication program was written between the ESP8266 communication module and the Arduino Uno development board to achieve information transfer between the upper and lower level machines. A program was written to establish a local area network (LAN) using the ESP8266, and an HTML-based control website page was designed. Smart terminals can access the control website address and directly control the airship via the webpage by connecting to the LAN's WiFi signal established by the ESP8266.

[0054] Based on the manual control program, the acceleration measured by the MPU6050 attitude sensor is integrated using the basic principles of the PID algorithm to obtain the airship's displacement information, thereby realizing the airship's automatic altitude maintenance function, i.e., closed-loop control of motion state. Attitude angle information can also be used to further develop functions such as automatic attitude adjustment of the airship. The basic parameters of the measured airship motion performance are shown in Table 2.

[0055] Table 2

[0056]

[0057] Understandably, current technical solutions utilize the integrated photogrammetric 3D modeling software Reality Capture to achieve photogrammetric modeling of arbitrary 3D shapes or enclosed spaces. The specific implementation method for 3D modeling is as follows: For a single object, the airship flies around it at a fixed radius, maintaining a constant distance between the camera and the object, and takes photos of different angles of the object at relatively even angular intervals. The camera's viewing angle is controlled by adjusting the servo angle to ensure that eye-level, top-down, and bottom-up views are all taken. For an enclosed space, the airship also flies around it at a fixed radius, taking photos from multiple angles. An interactive flying-around program to control different turning radii is written and pre-written into the development board. Motion control is achieved through a control website, and an altitude-keeping program is integrated into the flying-around program to ensure motion stability when flying around at different altitudes. A smart terminal connected to the image transmission receiver views the real-time camera feed and controls the shooting; photos are automatically saved locally. The photos are imported into the software, and appropriate adjustments are made using tools such as adding control points and simplifying high-polygon models to automatically obtain a digital 3D model of the shape or space. With current technology, creating a 3D model of a single object requires more than 20 photos from multiple angles, with a maximum framing angle of 45° between adjacent shots, a 5% volume loss rate in the 3D model, and a modeling calculation time of approximately 30 seconds. The flight path is as follows... Figure 4 As shown.

[0058] Example 2

[0059] Figure 5 This is a flowchart of an airship control method for automatic modeling of indoor 3D objects according to an embodiment of the present invention, such as... Figure 1 As shown, it includes:

[0060] S1 establishes the basic motion control logic for the airship. PWM control signals are output through the Arduino Uno development board to drive two sets of hollow cup motors. Specifically, the rotor speed and direction of the two upper vertical rotating surfaces are controlled to achieve forward, backward, left, and right turns of the airship. The rotor speed of the two lower horizontal rotating surfaces is controlled to achieve ascent, descent, and hovering of the airship. The four rotors are arranged in layers, with independent power supply and control, avoiding airflow interference and completing the decoupled control of the airship's multi-degree-of-freedom motion.

[0061] S2 constructs a WiFi-based remote manual control mechanism. It establishes a local wireless LAN through the ESP8266 communication module and runs an embedded web server to provide a graphical user interface. After the smart terminal connects to the network, it sends flight commands through a webpage. The ESP8266 receives and forwards the commands to the Arduino Uno development board, triggering the corresponding basic motion control program to achieve human-machine interactive manual control.

[0062] S3 enables closed-loop automatic altitude maintenance. It uses the MPU6050 attitude sensor to collect the airship's three-axis acceleration and attitude angle data in real time and transmits them to the Arduino Uno development board. The PID control algorithm is used to process the sensor data and dynamically adjust the PWM output of the lower-level lift rotor to keep the airship stable within the set altitude range and suppress vertical disturbances.

[0063] S4 executes the automatic flight modeling control program, calls the preset circular or spiral flight path algorithm, and controls the upper propulsion rotor to run at a set speed and radius while maintaining altitude, driving the airship to fly horizontally around the target object; at the same time, the camera pitch angle is adjusted by the servo motor to realize continuous acquisition of multi-view images and complete the data acquisition before 3D modeling.

[0064] Specifically, the step of "constructing the airship platform" in this invention is the basic hardware architecture design for realizing the automatic modeling function of 3D objects. Its technical implementation principle is based on the organic combination of aerodynamics and flight control system. The airship platform adopts a near-spherical soft aluminum membrane gasbag as the main lift structure. This gasbag is made of high-strength, low-mass aluminum membrane material and filled with helium to achieve stable buoyancy support. Compared with traditional ellipsoidal or spindle-shaped gasbags, the near-spherical structure has more uniform aerodynamic characteristics, which helps to reduce attitude disturbances during flight and improve image stability during modeling.

[0065] In terms of implementation, the airship platform adopts a layered rigid pod structure with four layers, each housing the control unit, power system, power module, and image acquisition equipment. The pod supports are made of lightweight aluminum alloy or carbon fiber, ensuring overall structural rigidity while keeping weight within a reasonable range. The power system consists of four sets of micro rotors driven by coreless motors. Two sets are horizontal propulsion rotors with vertical rotation surfaces, used to control the airship's lateral movement; the other two sets are vertical lift rotors with horizontal rotation surfaces, used to adjust the airship's vertical altitude. The four rotors are arranged in a layered axisymmetric layout, with the lift rotors on the lower layer and the propulsion rotors on the upper layer, avoiding wake interference and improving propulsion efficiency and flight stability.

[0066] Specifically, the airship's gasbag diameter is approximately 80cm, and the helium filling volume is controlled at... Within a certain range, to ensure a balance between lift and structural strength. The rotor diameter is 100mm, the coreless motor has a rated voltage of 3.7V, a maximum output speed of 12000RPM, and the drive module uses an XY-2.5AD, supporting PWM signal adjustment of the motor speed. The MPU6050 attitude sensor has a sampling frequency of 200Hz and an attitude angle accuracy of ±0.1°, meeting the requirements of closed-loop control. The airship's maximum climb speed is approximately 0.5m / s, the minimum turning radius is 0, and the endurance is up to 30 minutes.

[0067] This step is primarily used in practical applications for 3D modeling tasks in enclosed indoor spaces or vulnerable environments, such as cultural relics, caves, and building interiors. By leveraging the airship's stable hovering and circling capabilities, combined with multi-angle images captured by cameras, high-precision 3D reconstruction can be achieved. Its technological value lies in providing a simple, reliable, and low-cost airship platform. Compared to the complex vector propulsion or flapping-wing structures of existing technologies, this solution is easier to automate and deploy on a large scale, possessing excellent engineering practicality and market potential.

[0068] In one embodiment of the invention, the near-spherical soft aluminum membrane airbag has a diameter of 80 cm and is filled with helium to provide stable lift.

[0069] Specifically, in this invention, the diameter of the near-spherical soft aluminum membrane gasbag is set at 80 cm, and it is filled with helium to provide stable lift. This is one of the core structural designs for achieving efficient, safe, and controllable flight of the airship platform. The technical principle behind this step is based on the combination of gas buoyancy and the properties of the gasbag material. By rationally selecting the gasbag size and filling gas, the airship is ensured to have good lift performance and structural stability in indoor or confined spaces.

[0070] In some implementations, the near-spherical soft aluminum membrane airbag employs multi-layered composite aluminum membrane materials (such as Mylar or Aluminum Foil Laminated Film), with a thickness typically between 0.1-0.2 mm, to balance airtightness and lightweight requirements. The airbag's overall shape is near-spherical, offering a smaller frontal area and superior aerodynamic performance compared to traditional ellipsoidal or spindle-shaped designs, helping to reduce airflow disturbance and energy consumption during flight. The diameter is set at 80 cm, based on a balance calculation between the airship's overall mass (approximately 250g) and the required net lift, ensuring optimal performance at helium densities (approximately...). ) and air density (approximately Under these conditions, the airship can obtain sufficient net buoyancy to achieve stable suspension and slow movement.

[0071] Specifically, the amount of helium filled needs to be precisely controlled based on the gasbag volume. Taking a near-spherical gasbag with a diameter of 80cm as an example, its theoretical volume is approximately 268L. After being filled with helium, it can generate a net lift of approximately 268 × (1.225 - 0.1786) = 276g. Considering the total mass of the airship (approximately), the weight of the pod and the power of the propulsion system need to be reasonably configured so that the net weight of the airship is slightly greater than the net buoyancy, thereby achieving the automatic altitude holding function with a small thrust. In addition, helium filling must be carried out under standard atmospheric pressure (101.325kPa) and normal temperature (20-25℃) conditions to ensure uniform gasbag expansion and no risk of excessive stretching or leakage.

[0072] In practical applications, this step is suitable for interior design, 3D modeling of cultural relics and historical sites, and surveying of caves or enclosed spaces. In these environments, airships need to fly stably for extended periods and maintain high consistency. Helium-filled near-spherical aluminum membrane gasbags can provide continuous and stable lift, avoiding flight instability caused by insufficient battery power or rotor thrust fluctuations.

[0073] Furthermore, the technical effect of this step is to significantly improve the airship's lift efficiency and flight stability, while reducing its dependence on the power system and extending its endurance. By employing lightweight, highly airtight aluminum membrane materials and a reasonable helium filling strategy, the airship can maintain its levitational state even without external thrust input, providing a solid platform foundation for subsequent automatic flight maneuvers and 3D modeling. This design achieves a good balance between structural simplicity and functional reliability, which is one of the key innovations that distinguishes this invention from existing technologies.

[0074] In one embodiment of the present invention, the layered rigid pod structure includes four layers of support, wherein the first layer is used to fix the Arduino Uno development board and the horizontal propulsion rotor, the second layer is used to fix the ESP8266 communication module and the vertical propulsion rotor, the third layer is used to fix the lithium battery pack, and the fourth layer is used to fix the servo motor and the integrated image transmission camera.

[0075] Specifically, the layered rigid pod structure described in this invention is a key structural design for achieving stable mounting and functional integration of the airship platform. This structure consists of four support layers, each responsible for different functional modules, ensuring the airship possesses excellent motion control capabilities and image acquisition performance in three-dimensional space.

[0076] In some implementations, the first-layer support is primarily used to secure the Arduino Uno development board and the horizontal propulsion rotor. The Arduino Uno, as the airship's main control unit, receives commands from the ESP8266 and coordinates the outputs of the various motor drive modules. The horizontal propulsion rotor is driven by two 720-type coreless motors with horizontal rotation surfaces, mounted on the left and right cantilever ends of the first-layer support. PWM signal modulation is achieved through the XY-2.5AD motor drive module to control the airship's forward and backward movement and steering. This layer design must ensure reasonable wiring between the development board and the motors to avoid electromagnetic interference, while rigid connections ensure structural stability and prevent signal transmission abnormalities due to vibration during flight.

[0077] The second support layer is used to secure the ESP8266 communication module and the vertical propulsion rotor. The ESP8266, as the airship's WiFi communication module, is responsible for establishing a local area network connection with the ground-based smart terminal and transmitting control commands to the Arduino Uno development board. The vertical propulsion rotor is also driven by two 720-type hollow cup motors, with the rotation plane facing vertically, used to adjust the airship's vertical motion and attitude. This layer is arranged axially symmetrically with the first layer to balance the airship's aerodynamic performance, while also preventing interference between rotor wakes and improving propulsion efficiency.

[0078] The third support layer is used to secure a 3.7V lithium battery pack, consisting of four cells with a total weight of 100g. The lithium batteries provide a stable voltage to each electronic module via an AMS1117 transformer module, ensuring the normal operation of the control system under different loads. This layer's design must consider battery heat dissipation and securing methods to prevent displacement or short-circuit risks during flight.

[0079] The fourth support layer is used to mount the SG90 servo motor and the integrated FPV image transmission camera. The servo motor controls the camera's pitch angle via PWM signals to achieve multi-angle image acquisition; the image transmission camera transmits real-time images to a ground base station via wireless signals, facilitating remote monitoring and modeling control by operators. This layer must ensure an unobstructed field of view for the camera, and the support structure must have sufficient rigidity to reduce image jitter during flight.

[0080] This layered rigid pod structure, through modular design and axisymmetric layout, effectively enhances the airship's structural stability and functional integration. The layers are connected by resin or carbon fiber materials, keeping the total weight within a reasonable range and ensuring the airship's long endurance. This structural design is significantly innovative in 3D modeling of airships, providing reliable hardware support for subsequent automated flight path and modeling algorithms.

[0081] In one embodiment of the present invention, a dual-development-board control architecture is configured, wherein the Arduino Uno development board is used to control the motor drive module and the servo motor, and the ESP8266 communication module is used to establish a local area network and receive remote control commands from the smart terminal. The control commands are transmitted to the Arduino Uno development board to realize the motion control of the airship.

[0082] Specifically, this step involves configuring a dual-development-board architecture in the airship control system, specifically the collaborative operation of the Arduino Uno development board and the ESP8266 communication module to achieve efficient integration of remote control and local execution. In some implementations, the Arduino Uno development board acts as the main control unit, responsible for real-time control of the motor drive module and servos, while the ESP8266 communication module acts as the communication hub, receiving remote control commands from smart terminals (such as mobile phones or tablets) through a local area network (LAN), and transmitting the commands to the Arduino Uno development board via UART or SoftwareSerial, thereby achieving motion control of the airship.

[0083] At the parameter level, the ESP8266 communication module, configured in Access Point (AP) mode, creates an independent WiFi network. Its default SSID and password can be customized by the user, typically set to "Blimp_Controller" and "12345678" to ensure convenient and secure connection. After connecting to this WiFi network, the smart terminal accesses the preset IP address (e.g., 192.168.4.1) and loads an HTML control page run by the ESP8266. This page interacts with the ESP8266 via JavaScript, encapsulating user-input control commands (such as forward, backward, left turn, right turn, servo steering, etc.) into JSON format or ASCII strings, sending them to the ESP8266 via the WiFi module, and then the ESP8266 transmits the commands to the Arduino Uno development board via serial communication.

[0084] Specifically, the Arduino Uno development board uses pre-defined PWM control logic to convert received commands into output signals for the motor drive module (e.g., the coreless motor), controlling its speed and direction to adjust the airship's lift and horizontal propulsion. Servo control adjusts the servo angle via PWM signals, enabling flexible adjustment of the camera's viewing angle. To ensure real-time and stable communication, the serial communication baud rate between the ESP8266 and Arduino is typically set to 115200 bps to reduce data transmission latency.

[0085] Specifically, this dual-development-board architecture is particularly suitable for indoor 3D modeling tasks, such as high-precision image acquisition of enclosed spaces like cultural relics, caves, and building interiors. By remotely controlling the airship's trajectory and camera angles, operators can complete multi-angle shooting from a safe distance, providing high-quality image data for subsequent 3D modeling software (such as Reality Capture).

[0086] The technical effect of this step is that by separating the communication and control functions to two development boards, ESP8266 and Arduino, it not only improves the modularity and scalability of the system, but also significantly enhances the remote control capability and motion stability of the airship, providing reliable technical support for achieving automatic flight, attitude maintenance and 3D modeling.

[0087] In one embodiment of the present invention, the Arduino Uno development board controls two motor drive modules respectively through PWM signals, and each module drives two hollow cup motors.

[0088] Specifically, in this invention, the Arduino Uno development board controls two motor drive modules via PWM (Pulse Width Modulation) signals. Each module drives two hollow cup motors, thereby achieving multi-degree-of-freedom motion control of the airship. This step is the core of the airship's propulsion system control, and its technical implementation is based on the coordinated operation of embedded control and motor drive.

[0089] In some implementations, the Arduino Uno development board acts as the main control unit, sending speed control signals to the two drive modules respectively through its digital PWM output pins (such as D3, D5, D6, and D9). The XY-2.5AD is a dual-channel H-bridge driver chip designed specifically for small DC motors, supporting a maximum continuous current of 2A and a voltage range of 2.7V to 11V, suitable for driving the 720 series coreless motors in this invention. Each XY-2.5AD module can independently control two motors, corresponding to the two horizontal propulsion rotors or two vertical lift rotors of the airship. By setting different PWM duty cycles (typically between 0% and 100%), the motor speed can be adjusted, thereby controlling the rotor thrust; by reversing the polarity of the PWM signal, the motor rotation direction can be changed, achieving lift adjustment and attitude control of the airship.

[0090] Furthermore, the frequency of the PWM signal is typically set between 1kHz and 20kHz to ensure rapid motor response and smooth operation, avoiding motor jitter or excessive electromagnetic interference caused by excessively low frequencies. In this invention, a 16-bit timer is used to generate precise PWM waveforms to meet the power requirements of the airship under different motion states. In addition, the Arduino Uno development board communicates with the ESP8266 communication module via a serial port, receiving commands from the remote control terminal and dynamically adjusting the PWM output parameters to achieve remote control of the airship and motion path planning in automatic modeling tasks.

[0091] In practical applications, especially in enclosed indoor spaces or archaeological caves, this step ensures the airship can stably and flexibly adjust its flight attitude and altitude, thereby enabling multi-angle image acquisition of target objects. By precisely controlling the motor speed and direction, the airship can perform complex maneuvers such as circling, hovering, and ascent / descend, providing high-quality image data for subsequent 3D modeling. This control method has advantages such as simple structure, rapid response, and controllable power consumption, significantly improving the practicality and control precision of the airship system.

[0092] In one embodiment of the present invention, the ESP8266 communication module constructs a control webpage using HTML, and the smart terminal accesses the webpage by connecting to the local area network WiFi signal to send control commands.

[0093] Specifically, in this invention, the ESP8266 communication module constructs a control webpage using HTML and communicates with a smart terminal via a local area network (LAN) WiFi signal, thereby enabling the transmission of remote control commands. This step is a crucial link in realizing human-machine interaction and remote control in the airship control system.

[0094] Furthermore, the ESP8266 communication module acts as a host computer, running a WiFi Access Point (AP) mode program developed based on the Arduino IDE to create an independent local area network (LAN) WiFi hotspot. Smart terminals (such as smartphones or tablets) can access a control webpage dynamically generated by the ESP8266 by connecting to this hotspot. This webpage is written in HTML, combined with JavaScript and CSS to create an interactive interface containing multiple control buttons or sliders, corresponding to operations such as forward, backward, left turn, right turn, braking, hovering, and camera angle adjustment for the airship. When the user clicks or slides controls on the webpage, JavaScript encapsulates the operation instructions into HTTP requests, which are then sent to the ESP8266 communication module on the airship via the ESP8266's WiFi interface.

[0095] Furthermore, the ESP8266 communication module operates in the 2.4GHz band, supports the 802.11 b / g / n protocol, and has a maximum transmission rate of 72.2Mbps. The local area network (LAN) WiFi signal coverage radius is approximately 30 meters, meeting the control requirements of enclosed indoor spaces. Webpage response time is controlled within 200ms to ensure the real-time nature of control commands. Control commands are transmitted to the Arduino Uno development board via serial communication (UART) in ASCII format, with a baud rate set to 9600 bps, ensuring the stability and accuracy of data transmission.

[0096] This control webpage can be deployed in various scenarios where the airship performs 3D modeling tasks, such as interior design, cultural relic protection, and surveying of enclosed spaces like caves or tunnels. Users do not need to install a dedicated app; they can remotely control the airship simply through a browser, greatly improving ease of operation and system compatibility.

[0097] This step enables wireless and visual control of the airship's control system, overcoming the distance and complexity limitations of traditional Bluetooth or infrared control methods. Through a standardized web interface protocol, the system possesses excellent scalability, allowing for the integration of more sensor data or the introduction of automated control logic in the future, laying the foundation for the intelligent development of airships.

[0098] In one embodiment of the present invention, the airship's three-axis acceleration and attitude angle data are collected in real time based on the MPU6050 attitude sensor, and the data is adjusted in a closed loop using a PID algorithm to achieve motion stability of the airship when flying around different altitude planes.

[0099] Specifically, this step involves real-time acquisition of the airship's three-axis acceleration and attitude angle data using the MPU6050 attitude sensor, and closed-loop regulation of the airship's motion state through a PID (proportional-integral-derivative) algorithm to achieve motion stability during flight around different altitude planes. This step is the core of the airship's automatic control system, directly determining its dynamic response accuracy and flight stability in three-dimensional space.

[0100] The MPU6050 is an inertial measurement unit (IMU) that integrates a triaxial accelerometer and a triaxial gyroscope. The bus connects to the Arduino Uno development board. Its sampling frequency can be set to 1kHz, with acceleration measurement ranging from ±2g to ±16g and angular velocity measurement ranging from ±250° / s to ±2000° / s. During airship operation, the MPU6050 continuously collects the airship's linear acceleration in the x, y, and z directions, as well as attitude information such as pitch, yaw, and roll angles. This data is processed by the Arduino Uno development board and used as input signals for the PID controller.

[0101] The PID algorithm calculates the deviation between the current attitude and the target attitude in real time, and generates a control output signal by combining the weighting coefficients of the proportional (P), integral (I), and derivative (D) terms. This signal adjusts the PWM (Pulse Width Modulation) signals of each rotor, thereby controlling the motor speed and thrust distribution. For example, when the airship's pitch angle deviates from the set value due to airflow disturbance, the PID controller adjusts the thrust difference between the front and rear rotors according to the magnitude of the deviation to restore the airship's balance. Regarding altitude maintenance, by integrating the three-axis accelerations, the airship's vertical displacement can be estimated, and combined with the set altitude target, closed-loop lift regulation can be achieved.

[0102] The parameters (Kp, Ki, Kd) of the PID controller need to be adjusted according to the dynamic response characteristics of the airship. In some implementations, Kp is set to 0.8, Ki to 0.05, and Kd to 0.2 to balance response speed and system stability. The sampling rate of the MPU6050 is set to 100Hz to ensure the real-time performance and continuity of attitude data.

[0103] This step is particularly suitable for airships to perform flight modeling of 3D objects in enclosed indoor spaces, caves, ancient ruins, and other similar environments. The airship needs to switch between different altitude planes and maintain stable flight to ensure that the cameras can acquire high-quality, multi-angle image data. Through closed-loop adjustment, the airship can overcome factors such as airflow disturbances and structural flexibility to achieve precise trajectory control.

[0104] The technical advantage of this step lies in significantly improving the airship's motion stability and control accuracy in complex 3D environments, providing a reliable data acquisition platform for subsequent 3D modeling. Compared to traditional airships that rely on manual operation or open-loop control, this solution achieves automatic adjustment through sensor feedback and PID algorithms, enhancing the system's robustness and practicality.

[0105] In one embodiment of the present invention, the attitude angle data includes pitch angle, yaw angle and roll angle, which are used to adjust the flight attitude of the airship.

[0106] Specifically, in this invention, the acquisition and adjustment of attitude angle data is one of the core steps in achieving stable attitude control of the airship. Attitude angles include pitch, yaw, and roll, which correspond to the airship's rotation angles around the X, Y, and Z axes, respectively, and are used to describe the airship's attitude changes in three-dimensional space. In some implementations, the airship is equipped with an MPU6050 six-axis inertial measurement unit (IMU). This sensor, through its built-in three-axis accelerometer and three-axis gyroscope, acquires the airship's angular velocity and linear acceleration data in real time and transmits the data via a digital interface (…). The raw data is transmitted to the Arduino Uno main control development board for processing.

[0107] Furthermore, the Arduino Uno development board uses complementary filtering or Kalman filtering algorithms to fuse and calculate attitude angles based on the raw data output from the MPU6050, thereby improving measurement accuracy and anti-interference capabilities. The attitude angle update frequency is typically set to 100Hz to 200Hz to meet the real-time requirements of the airship's dynamic response. In the control logic, the attitude angle data is input as a feedback signal to the PID controller. The controller calculates the corresponding PWM output signal based on the deviation between the set target attitude and the actual attitude, and adjusts the speed and direction of the four rotors respectively, thereby realizing the automatic adjustment of the airship's pitch, yaw, and roll attitudes.

[0108] Optionally, in specific application scenarios, such as 3D modeling of cultural relics or cave interiors, the airship needs to maintain a stable flight attitude in complex environments to ensure the continuity of image acquisition and the accuracy of modeling. In this case, the attitude angle adjustment function is particularly important, as its control precision directly affects the airship's hovering stability and the accuracy of its flight trajectory. According to experimental tests, the attitude angle adjustment error of the airship of this invention is controlled within ±2°, and the response time is less than 0.5 seconds, meeting the requirements for low-speed, high-precision flight control indoors.

[0109] This step plays a crucial role in the entire technical solution, providing a stable and reliable flight platform support for the airship's automatic altitude maintenance, flight path planning, and 3D modeling image acquisition, significantly improving the airship's autonomous operation capability and modeling efficiency in complex spaces.

[0110] In one embodiment of the present invention, the PID algorithm converts triaxial acceleration data into real-time displacement information of the airship through integral calculation for automatic altitude holding control.

[0111] Specifically, in this invention, the PID algorithm converts triaxial acceleration data into real-time displacement information of the airship through integral operations, which is used to achieve automatic altitude-holding control. This step is a key link in realizing closed-loop control in the airship control system. Its technical implementation principle is based on the proportional-integral-derivative (PID) control strategy in classical control theory. Combining the output data of the acceleration sensor, the displacement change of the airship in the vertical direction is estimated through numerical integration methods, thereby dynamically adjusting the rotational speed of the lift rotor to maintain the stable flight of the airship at the set altitude.

[0112] The airship's MPU6050 triaxial accelerometer collects real-time acceleration data in the x, y, and z directions, with the z-axis corresponding to the vertical direction. Since acceleration is the second derivative of displacement, displacement information can be obtained through two integration operations. In practice, the Arduino Uno development board reads the raw acceleration data from the MPU6050 at a fixed sampling frequency (e.g., 50Hz) and performs numerical integration on the z-axis acceleration to obtain the airship's instantaneous velocity and displacement. To improve integration accuracy, the system uses a low-pass filter to preprocess the raw acceleration signal to suppress high-frequency noise interference and ensure the stability of the integration results.

[0113] The PID controller's integral gain (Ki) is set to 0.05, the integral time constant (Ti) to 20ms, and the update cycle of the integral term is consistent with the sensor sampling frequency. Trapezoidal integration is used for integration to reduce numerical errors. The airship's vertical displacement error is controlled within ±5cm, and the altitude hold response time is less than 1 second, meeting the flight stability requirements in indoor 3D modeling scenarios.

[0114] This step is primarily used for the airship's automatic altitude-keeping function when performing flight-around modeling tasks. For example, when creating 3D models of the interior of caves or grottoes, the airship needs to perform stable flight around different altitudes to ensure the continuity of the shooting angle and the accuracy of the modeling. Closed-loop control achieved through PID integral calculation can effectively cope with external disturbances such as airflow disturbances and load changes, improving the airship's autonomous flight capability in complex environments.

[0115] The technical advantage of this step lies in converting acceleration data into displacement information, enabling automatic vertical altitude adjustment of the airship and improving the system's control accuracy and robustness. Compared to traditional solutions relying on infrared ranging or visual positioning, this method eliminates the need for additional sensors, reducing system complexity and cost, while simultaneously enhancing the airship's practicality and reliability in 3D modeling tasks.

[0116] In one embodiment of the present invention, a preset flight path is executed. The flight path includes controlling the airship to fly around the target object with a fixed radius, adjusting the camera angle to obtain image data from eye level, top view and bottom view angles, and transmitting the image data to the ground base station in real time through an image transmission device.

[0117] Furthermore, the basic manual control program for the airship in this control method specifically includes forward, backward, turning, and ascent / descent. The specific operation method is to control the four rotors separately through PWM signals. Forward / backward movement is achieved by rotating the horizontal propulsion rotors in the same direction, ascent / descent is achieved by rotating the vertical propulsion rotors in the same direction, and turning is achieved by having the vertical propulsion rotors working while the two horizontal propulsion rotors rotate in opposite directions or one side rotates independently.

[0118] Understandably, the basic manual control program for the airship uses an Arduino development board to output PWM signals, independently adjusting the speed and direction of the four rotors to achieve precise control with multiple degrees of freedom. The specific operation method is as follows:

[0119] Forward / Reverse: Controls the propulsion rotors in the two upper horizontal planes to rotate synchronously forward or backward, generating forward or backward thrust to achieve linear motion of the airship along the longitudinal axis;

[0120] Lifting and Descent: Adjusting the rotation speed of the lifting rotors in the two vertical planes of the lower layer simultaneously increases or decreases the speed, thereby changing the overall lift and enabling the airship to ascend or descend vertically.

[0121] Hovering: At a set altitude, the rotational speed of each rotor is dynamically fine-tuned based on the attitude data fed back by the MPU6050 to balance lift and gravity and maintain spatial stability;

[0122] Turning (Yaw): A differential vector control strategy is adopted, which activates the two vertical rotors to rotate in opposite directions to provide yaw torque, or makes the horizontal propulsion rotors on both sides rotate in opposite directions to generate torque; it is also possible to activate only one side of the horizontal rotor to form asymmetrical thrust and achieve left or right turn;

[0123] Attitude fine-tuning (pitch / roll): By asymmetrically adjusting the rotational speed of the left and right or front and rear rotors, the airship can be pitched / raised or rolled to assist in path adjustment.

[0124] All actions are triggered by the user sending commands through the web interface built by the ESP8266 communication module via a smart terminal. After parsing, the Arduino executes the corresponding PWM output logic to achieve intuitive, low-latency manual flight control.

[0125] Specifically, in some implementations, executing a preset flyaround procedure is a key step in the airship platform used for automatic 3D object modeling in this invention. Its core lies in achieving high-precision 3D modeling of the target object through the airship's autonomous movement and multi-angle image acquisition from cameras. The technical principle behind this step is based on the closed-loop control of the airship's propulsion system and the coordinated scheduling of the image acquisition system, combined with a preset flyaround path algorithm. This ensures the airship flies stably around the target object with a fixed radius. Simultaneously, servo motors control the cameras to acquire image data from eye-level, top-down, and bottom-up angles, and the images are transmitted in real-time to a ground base station via an integrated image transmission device.

[0126] In its operation, the airship uses an Arduino Uno development board to control four miniature rotors driven by hollow cup motors. Two horizontal rotors adjust the airship's horizontal movement, while two vertical rotors control lift and altitude. During the flyaround procedure, the airship centers on the target object, setting a flyaround radius between 0.5 and 2 meters and an angle interval between 15° and 30° to ensure uniform and complete image coverage. During the flyaround, the MPU6050 attitude sensor collects the airship's attitude angles and acceleration data in real time, using a PID algorithm for closed-loop control to maintain stable flight within the set altitude and radius range.

[0127] The camera connects to the Arduino Uno development board via an SG90 servo motor. The servo motor's angle control range is -90° to +90°, allowing switching between three main camera perspectives: horizontal, downward (30°), and upward (30°). The image acquisition frequency is set to capture one image per flight angle, with a total of at least 20 images. The maximum angle between adjacent lenses does not exceed 45° to meet the input requirements of the 3D modeling software Reality Capture. The integrated image transmission device uses FPV (First Person View) wireless transmission technology, operating on the 5.8GHz frequency band, with a transmission latency of less than 200ms. It supports 720P or 1080P image resolution, ensuring real-time image data and clarity.

[0128] This step is particularly suitable for practical applications, especially in interior design, cultural relic preservation, and 3D modeling scenarios in caves or enclosed spaces. Utilizing the airship's low speed, low noise, and long endurance, the risk of collisions with fragile objects is avoided, while maintaining image clarity in dust-free or low-dust environments. In terms of technical effectiveness, this fly-around procedure, combining image acquisition and transmission technology, achieves multi-view, high-precision, and low-interference 3D modeling of target objects. Modeling computation time is controlled within 30 seconds, and the model volume loss rate is less than 5%, significantly improving modeling efficiency and data quality.

[0129] In one embodiment of the present invention, an image data preprocessing step is performed, which includes denoising, contrast enhancement, and viewpoint correction of the images acquired by the integrated image transmission camera, so as to improve the recognition accuracy and modeling efficiency of the 3D modeling software.

[0130] Specifically, in this invention, the image data preprocessing step is a crucial step in the automatic 3D object modeling process. Its technical implementation principle is based on a joint processing mechanism of image enhancement and geometric correction, aiming to improve the recognition accuracy and modeling efficiency of subsequent 3D modeling software (such as Reality Capture). This step mainly includes three sub-processes: image denoising, contrast enhancement, and viewpoint correction, which are optimized from the aspects of image quality, visual feature sharpness, and spatial geometric consistency, respectively.

[0131] For image denoising, a denoising algorithm combining median filtering and bilateral filtering is employed. Median filtering removes salt-and-pepper noise, with a window size typically set to 3×3 or 5×5 to smooth random noise in the image while preserving edge information. Bilateral filtering performs weighted averaging in both the spatial and gray-level domains, with a window radius of 5 pixels, a spatial standard deviation σ_s of 10, and a gray-level standard deviation σ_r of 20. This suppresses Gaussian noise while maintaining image details and improving the feature matching success rate during modeling.

[0132] The contrast enhancement section employs an adaptive histogram equalization algorithm with a block size of 8×8 pixels and a contrast limiting factor of 0.01 to avoid image distortion caused by over-enhancement. This algorithm can enhance the contrast of local image regions, and is particularly suitable for modeling objects with uneven lighting or reflective surfaces, thereby improving the recognizability of object contours and textures in the image.

[0133] Viewpoint correction is achieved through an image calibration method based on homography transformation. During the airship fly-around modeling process, the images captured by the camera may have problems such as tilt and distortion. By pre-calibrating the camera's intrinsic parameters (focal length, principal point coordinates, distortion coefficients) and extrinsic parameters (rotation matrix and translation vector), combined with the real-time attitude angle data provided by the airship attitude sensor (MPU6050), geometric correction can be performed on the images to eliminate viewpoint deviations caused by changes in airship attitude and ensure the alignment accuracy of multi-view images in three-dimensional space.

[0134] This step is of significant value in practical applications, especially in 3D modeling tasks in enclosed spaces such as caves and grottoes. Preprocessed image data can effectively improve the robustness and convergence speed of 3D reconstruction algorithms, reduce the number of images required for modeling, and lower modeling errors. For example, in the current approach, more than 20 images are required for modeling, with a maximum framing angle of 45° between adjacent shots. Without preprocessing, this number might need to be increased to more than 30 images to achieve the same modeling accuracy.

[0135] The airship control method for automatic modeling of indoor 3D objects according to the present invention can realize automatic flying around and photographing and modeling of 3D objects or enclosed spaces, effectively overcoming the problems of complex control, short communication distance and lack of clear application scenarios of traditional airships.

[0136] In the description of this specification, the references to terms such as "one embodiment," "some embodiments," "example," "specific example," or "some examples," etc., indicate that a specific feature, structure, material, or characteristic described in connection with that embodiment or example is included in at least one embodiment or example of the present invention. In this specification, the illustrative expressions of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in one or more embodiments or examples. Moreover, without contradiction, those skilled in the art can combine and integrate the different embodiments or examples described in this specification, as well as the features of different embodiments or examples.

[0137] Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include at least one of that feature. In the description of this invention, "a plurality of" means at least two, such as two, three, etc., unless otherwise explicitly specified.

Claims

1. A small airship device for automatic modeling of indoor 3D objects, characterized in that, include: External aerodynamic structure and internal control system, among which, The external aerodynamic structure includes a near-spherical soft aluminum membrane airbag; a multi-layer detachable rigid pod support fixed below the airbag; the support includes a four-layer structure, the first layer for fixing the main control board, with cantilever arms at both ends for mounting the horizontal propulsion rotor; the second layer for fixing the wireless communication module, with cantilever arms at both ends for mounting the vertical lift rotor; the third layer for fixing the power module; and the fourth layer for fixing the servo motor and camera. The internal control system uses an Arduino Uno development board as its core control unit, and includes a power system, an automatic control system, a WiFi communication system, and an image acquisition system; wherein: The power system includes at least two XY-2.5AD motor control modules and four coreless motors. The motor control modules are connected to the Arduino Uno development board and receive PWM control signals to drive the horizontal propulsion and vertical lift rotors, respectively. The automatic control system includes an MPU6050 attitude sensor connected to the Arduino Uno development board, which is used to collect the airship's three-axis acceleration and attitude angle to realize closed-loop control of flight attitude. The WiFi communication system includes a serial port connection between the Arduino Uno development board and the ESP8266 communication module, used to establish a WiFi local area network and receive remote control commands from smart terminals. The image acquisition system includes a servo motor connected to the Arduino Uno development board and an integrated image transmission camera fixed on the servo motor, which wirelessly transmits the images to a ground terminal.

2. The small airship device for automatic modeling of indoor three-dimensional objects as described in claim 1, characterized in that, The power system includes a lithium battery, four coreless motors, four micro rotors driven by the coreless motors, and two XY-2.5AD motor control modules. The lithium battery powers the motor control modules, which, based on PWM control signals from the Arduino Uno development board, drive the two sets of coreless motors to adjust their speed and direction. Two motors drive rotors with horizontal rotation surfaces to adjust the airship's lift, while the other two motors drive rotors with vertical rotation surfaces to provide horizontal thrust. The two sets of rotors are arranged in a layered axisymmetric configuration, with the lift rotor on the lower layer and the thrust rotor on the upper layer to avoid wake interference. The two sets of motors are powered and controlled independently, achieving decoupled adjustment of lift and thrust.

3. The small airship device for automatic modeling of indoor three-dimensional objects as described in claim 1, characterized in that, The automatic control system includes an MPU6050 attitude sensor, which transmits signals via... The interface is connected to the Arduino Uno development board for real-time acquisition of the airship's three-axis acceleration and attitude angle data. The Arduino Uno development board generates PWM control signals by running a preset adjustment program based on the received sensor data, and adjusts the motors of the power system to achieve closed-loop control of the airship's flight attitude.

4. The small airship device for automatic modeling of indoor three-dimensional objects as described in claim 1, characterized in that, The WiFi communication system includes an ESP8266 communication module, which is connected to the Arduino Uno development board via a serial communication interface. It is configured to establish a local WiFi area network and receive wireless control commands from smart terminals. After parsing the commands, it transmits them to the Arduino Uno development board in the form of digital signals, thereby realizing remote control of the power system, automatic control system and other functional modules.

5. The small airship device for automatic modeling of indoor three-dimensional objects as described in claim 1, characterized in that, The image acquisition and processing system includes a servo motor and a miniature camera. The servo motor is connected to the PWM control pin of the Arduino Uno development board and is controlled by remote commands to adjust the shooting angle. The miniature camera is fixed to the output end of the servo motor and rotates with the servo motor to achieve omnidirectional shooting; the camera is an integrated image transmission camera with wireless image transmission function; or, the camera is connected to a WiFi network through the ESP8266 communication module to achieve remote camera control based on wireless signals.

6. A method for controlling an airship for automatic modeling of indoor 3D objects, characterized in that, include: S1 establishes the basic motion control logic for the airship. PWM control signals are output through the Arduino Uno development board to drive two sets of hollow cup motors. Specifically, the rotor speed and direction of the two upper vertical rotating surfaces are controlled to achieve forward, backward, left, and right turns of the airship. The rotor speed of the two lower horizontal rotating surfaces is controlled to achieve ascent, descent, and hovering of the airship. The four rotors are arranged in layers, with independent power supply and control, avoiding airflow interference and completing the decoupled control of the airship's multi-degree-of-freedom motion. S2 constructs a WiFi-based remote manual control mechanism. It establishes a local wireless LAN through the ESP8266 communication module and runs an embedded web server to provide a graphical user interface. After the smart terminal connects to the network, it sends flight commands through a webpage. The ESP8266 receives and forwards the commands to the Arduino Uno development board, triggering the corresponding basic motion control program to achieve human-machine interactive manual control. S3 enables closed-loop automatic altitude maintenance. It uses the MPU6050 attitude sensor to collect the airship's three-axis acceleration and attitude angle data in real time and transmits them to the Arduino Uno development board. The PID control algorithm is used to process the sensor data and dynamically adjust the PWM output of the lower-level lift rotor to keep the airship stable within the set altitude range and suppress vertical disturbances. S4 executes the automatic flight modeling control program, calls the preset circular or spiral flight path algorithm, and controls the upper propulsion rotor to run at a set speed and radius while maintaining altitude, driving the airship to fly horizontally around the target object; at the same time, the camera pitch angle is adjusted by the servo motor to realize continuous acquisition of multi-view images and complete the data acquisition before 3D modeling.

Images