A lunar digital environment construction simulation system

Abstract

A lunar surface digital environment construction simulation system, a moon-earth space-time reference simulation module is used for providing a space-time reference for the whole simulation system and a conversion relationship between different space-time references; a moon surface data resource management module is used for generating a lunar surface multi-scale grid data by using remote sensing data and image data through alignment and multi-level division processing, for real-time dynamic loading according to a viewpoint position; a lunar surface comprehensive environment simulation module is used for modeling a lunar surface illumination, a starry sky background, a ground surface material, a topographic feature and a lunar dust dispersion; a simulation task working condition management module is used for establishing a detector model and a sensor model, and performing sensor configuration according to a requirement, providing data for the sensor and acquiring data output by the sensor; a lunar surface scene rendering demonstration module is used for rendering a scene image including a moon surface data, a lunar surface comprehensive environment and a detector model.

Description

Technical Field

[0001] This invention relates to a lunar surface digital environment construction simulation system, belonging to the field of deep space exploration technology. Background Technology

[0002] Manned lunar exploration and lunar base construction missions place higher demands on navigation, obstacle avoidance, and precise landing. Lunar surface topography and soil characteristics significantly impact the design and verification of environmental perception, feature recognition, and navigation, guidance, and control algorithms. Existing simulation environments are mostly localized virtual environments containing typical lunar surface features, or mechanical environments used for soft landing and lunar rover motion performance testing, as well as physical test environments simulated on the ground. However, the landing process spans a large spatial area, with different tasks and sensors used at each stage. Single-scale virtual environment simulations cannot support the verification of perception and decision-making algorithms throughout the entire landing process. Currently, there is no large-scale lunar digital environment based on real lunar surface data capable of simulating multi-dimensional attributes. Summary of the Invention

[0003] The technical problem to be solved by this invention is to overcome the shortcomings of the prior art and solve the problem of fine construction of the lunar digital environment.

[0004] The objective of this invention is achieved through the following technical solutions:

[0005] A lunar digital environment construction simulation system includes a lunar spatiotemporal benchmark simulation module, a lunar surface data resource management module, a lunar surface comprehensive environment simulation module, a simulation task condition management module, and a lunar scene rendering and demonstration module.

[0006] The Earth-Moon spacetime reference simulation module is used to provide a spacetime reference for the entire simulation system, as well as the conversion relationships between different spacetime references;

[0007] The lunar surface data resource management module utilizes remote sensing data and image data, and after alignment and multi-level segmentation, generates multi-scale raster data of the lunar surface, which is used for real-time dynamic loading according to the viewpoint position.

[0008] The lunar surface comprehensive environment simulation module is used to model lunar illumination, starry sky background, surface material, morphological features, and lunar dust distribution.

[0009] The simulation task condition management module is used to build detector models and sensor models, configure sensors according to requirements, provide data to sensors, and acquire data output by sensors.

[0010] The lunar scene rendering demonstration module is used to render scene images including lunar surface data, the overall lunar environment, and probe models.

[0011] Preferably, the time reference in the spatiotemporal reference includes at least sidereal time, UT, ephemeris time, and solar system center-of-mass mechanical time;

[0012] The spatial references in the spatiotemporal references include at least the Earth's center of mass coordinate system, the Moon's center of mass coordinate system, the planet's center of mass coordinate system, the Sun's ecliptic coordinate system, the spacecraft's own system, and the sensor coordinate system.

[0013] Preferably, when dynamically loading data in real time based on the viewpoint position, virtual terrain and ground reflection characteristic data are superimposed on the multi-scale raster data of the lunar surface.

[0014] Preferably, the method for overlaying virtual terrain data is as follows: on top of the resolution of the real terrain data, the original low-resolution lunar surface data is interpolated and encrypted using the random midpoint displacement method to generate fine terrain. Then, randomly arranged lunar craters and lunar rock data are added to generate virtual terrain with detailed features, maximizing the simulation of high-resolution lunar surface morphology.

[0015] Preferably, the method for superimposing ground reflection characteristic data is as follows: on digital orthophoto image data, material characteristic data describing the surface material and multi-spectral reflection characteristics are selectively superimposed; a reflection equation is established based on the geometric and optical properties of the surface material; and a bidirectional reflection distribution function is calculated or engineering vector data required for the simulation of other sensor measurement principles is added.

[0016] Preferably, the method for generating multi-scale raster data of the lunar surface using remote sensing data and image data, after alignment and multi-level segmentation processing, is as follows:

[0017] Based on digital elevation models describing the spatial distribution of lunar landforms and superimposed digital orthophoto images, multi-scale rasterized terrain data of the lunar surface is obtained through coordinate registration and hierarchical slicing of terrain and map layers.

[0018] Preferably, lunar multi-scale raster data is dynamically loaded in real time through a geographic information system data management and streaming plugin.

[0019] Preferred methods for modeling lunar illumination, starry background, surface material, morphological features, and lunar dust distribution include:

[0020] Obtain the positions of stars, the sun, planets, and the moon; based on these positions, construct a planetary visualization environment model and simulate the starry sky background.

[0021] Simulating lunar surface illumination and shadows based on the relative positions of the sun and moon can reflect the real lunar surface material and morphological characteristics in real time according to the simulation time and spatial location.

[0022] Based on simulation data of lunar dust particles, a spatial envelope model of particle clusters is established to realize scene modeling and visualization simulation of plume and lunar dust characteristics.

[0023] Preferably, the simulated data of lunar dust particles includes the spatial location, size, density, and mass of the lunar dust particles.

[0024] Preferably, the method for establishing detector and sensor models, configuring sensors according to requirements, and providing data to sensors is as follows:

[0025] Sensors include visible light imaging, three-dimensional laser imaging, and velocity and distance measurement sensors;

[0026] Model the three-dimensional digital model of the detector body, and according to the model configuration, call the required sensor models, and initialize the installation position, component parameters and working mode of each sensor according to the task requirements;

[0027] Based on the sensor input interface, retrieve the terrain, image, height, slant range, and reflection characteristics of the specified field of view or direction to provide true data for the sensor model measurement simulation.

[0028] Compared with the prior art, the present invention has the following advantages:

[0029] (1) Based on the real lunar topography database and local area exploration image data, this invention adds lunar surface comprehensive environment parameterization modeling, manually adds or randomly generates lunar surface feature elements, and constructs morphological data with small-scale detailed features to simulate high-resolution lunar surface morphology to the maximum extent.

[0030] (2) The simulation system established by the present invention can automatically retrieve the terrain data of the corresponding level according to the location of the lander, while meeting the requirements of terrain resolution and simulation real-time performance.

[0031] (3) This invention can receive external data to drive and call the particle system to simulate the lunar dust environment, simulate the real-time effect of the engine plume stirring up lunar dust during the landing process of the probe, and restore the real environment during the landing process of the probe to the greatest extent.

[0032] (4) The simulation system established by this invention can not only provide lunar environment scene simulation, but also serve as the target object of digital single-machine such as visible light imaging, three-dimensional laser imaging, velocity and distance measurement sensors, providing original measurement information such as images, three-dimensional measurement and slant distance, and providing environmental target simulation for closed-loop simulation. Attached Figure Description

[0033] Figure 1 This is a schematic diagram of the composition of the simulation system of the present invention. Detailed Implementation

[0034] To make the objectives, technical solutions, and advantages of the present invention clearer, the embodiments of the present invention will be described in further detail below with reference to the accompanying drawings.

[0035] A lunar surface digital environment construction simulation system, specifically a large-scale lunar surface digital environment fine-scale construction simulation system, such as... Figure 1 As shown, it includes:

[0036] (1) Earth-Moon Spatiotemporal Reference Simulation Module: Establishes a spatiotemporal reference and conversion model for space missions, providing a spatiotemporal description framework for simulation modeling of exploration missions; among which, the time reference and conversion model includes commonly used time references such as sidereal time (ST), Universal Time (UTC), Ephemeris Time (ET), and Solar System Center of Mass Mechanical Time (TDB) and their conversion relationships; the space reference and conversion model includes commonly used space references such as the Earth / Moon / Planetary Center of Mass Coordinate System (fixed-connected system, J2000 inertial coordinate system), Solar Ecliptic Coordinate System, Spacecraft Body System, and Sensor Coordinate System and their conversion relationships;

[0037] (2) Lunar Surface Data Resource Management Module: Stores remote sensing measurement and image data from the lunar exploration project. After spatial reference transformation model alignment and multi-level segmentation processing, it generates multi-scale rasterized terrain data of the lunar surface, loads it into the simulation system and dynamically loads it in real time according to the viewpoint position, and overlays refined virtual terrain and material data reflecting the ground reflection characteristics; the specific implementation process is as follows:

[0038] (2.1) Based on the digital elevation model (DEM) describing the spatial distribution of lunar landforms and superimposed digital orthophoto map (DOM) data, after coordinate registration and terrain and map layer-level slicing, the multi-scale rasterized terrain data of the lunar surface is loaded into the simulation system through the geographic information system (GIS) data management and streaming plugin;

[0039] (2.2) The level of detail (LOD) technique is used to load the multi-scale rasterized terrain data of the lunar surface in real time. On the resolution of the real terrain data, fractal technology is applied and random midpoint displacement method is used to interpolate and encrypt the original low-resolution lunar surface DEM data. Then, lunar craters and lunar rocks are manually added or randomly arranged on the generated fine terrain to generate virtual terrain with small-scale detailed features, maximizing the simulation of high-resolution lunar surface morphology.

[0040] (2.3) On the DOM data, material property data describing the surface material and multi-spectral reflectance characteristics can be selectively superimposed. The reflection equation can be established based on the geometric and optical properties of the surface material, thereby calculating the bidirectional reflectance distribution function (BRDF) or adding engineering vector data required for the simulation of other sensor measurement principles, so that the lunar surface topography as a sensing target has the ability to simulate multiple coupling effects.

[0041] (3) Lunar Surface Comprehensive Environment Simulation Module: Parametric modeling of the comprehensive environment, including star background, lunar illumination, lunar surface material, morphological features, and lunar dust distribution; the specific implementation process is as follows:

[0042] (3.1) Integrating planetary ephemeris and star catalogs, the positions of stars, the sun, planets and the moon can be accurately obtained. Based on the obtained planetary position data, a planetary visualization environment model can be built and the star background can be simulated.

[0043] (3.2) Based on the relative positional relationship between the sun and the moon, the simulation of lunar surface illumination and shadows can reflect the real lunar surface material and morphological characteristics in real time according to the simulation time and spatial location;

[0044] (3.3) Receive lunar dust particle simulation data from the digital lunar dust simulation system, including the spatial location, size, density, mass and other attribute data of lunar dust particles, establish a spatial envelope model of particle clusters, and use integrated lighting, shadow, concentration and hidden surface removal techniques to realize scene modeling and visualization simulation of plume and lunar dust characteristics under data-driven conditions.

[0045] (4) Simulation Task Condition Management Module: This module integrates detector models and environmental perception measurement sensor models, allowing for sensor and parameter configuration as needed to generate diverse task scenarios and simulation conditions. The specific implementation process is as follows:

[0046] (4.1) Integrate environmental perception sensor models, including visible light imaging, three-dimensional laser imaging, and velocity and distance measurement sensors.

[0047] (4.2) Model the three-dimensional digital model of the detector body, and call the required environmental perception sensor model according to the model configuration. Initialize the installation position, component parameters and working mode of each sensor according to the task requirements.

[0048] (4.3) Based on the input interface of the environmental perception sensor, retrieve physical quantities such as terrain, image, height, slant range, and reflection characteristics of the specified field of view or direction to provide true data for the sensor model measurement simulation;

[0049] (4.4) Triggered by onboard control logic or external commands, the sensor data acquisition and processing module is invoked to output the sensor simulation or processing results to the control system according to the given interface requirements, or to store and display the data.

[0050] (5) Lunar Scene Rendering Demonstration Module: Based on the 3D rendering engine and hardware acceleration technology, the simulation scene image composed of the above-mentioned lunar surface topography data, lunar surface comprehensive environment and probe model is rendered in real time to realize the 3D display and scene roaming of the large-scale lunar digital environment. It can provide multi-view display and multi-channel video stream push to support the joint simulation of multi-task systems.

[0051] The contents not described in detail in this specification are common knowledge to those skilled in the art.

[0052] Although the present invention has been disclosed above with reference to preferred embodiments, it is not intended to limit the present invention. Any person skilled in the art can make possible changes and modifications to the technical solutions of the present invention by utilizing the methods and techniques disclosed above without departing from the spirit and scope of the present invention. Therefore, any simple modifications, equivalent changes and alterations made to the above embodiments based on the technical essence of the present invention without departing from the content of the technical solutions of the present invention shall fall within the protection scope of the technical solutions of the present invention.

Claims

1. A lunar digital environment construction simulation system, characterized by, The simulation system comprises a moon-earth space-time reference simulation module, a moon surface data resource management module, a moon surface comprehensive environment simulation module, a simulation task working condition management module, and a moon surface scene rendering demonstration module. The moon-earth space-time reference simulation module is used for providing a space-time reference for the whole simulation system, and a conversion relationship between different space-time references. The moon surface data resource management module is used for generating moon surface multi-scale raster data by aligning and multi-level dividing remote sensing data and image data, and loading the data in real time according to a viewpoint position. The moon surface comprehensive environment simulation module is used for modeling moon surface illumination, starry sky background, ground surface material, topographic features, and moon dust distribution. The simulation task working condition management module is used for establishing a detector model and a sensor model, configuring the sensor according to a requirement, providing data for the sensor, and obtaining sensor output data. The moon surface scene rendering demonstration module is used for rendering a scene image comprising moon surface data, moon surface comprehensive environment, and a detector model. The moon surface multi-scale raster data is loaded in real time according to a viewpoint position, and virtual terrain and ground surface reflection characteristic data are superimposed on the moon surface multi-scale raster data.

2. The simulation system of claim 1, wherein, The time reference in the space-time reference comprises at least sidereal time, universal time, calendar time, and heliocentric mechanical time. The space reference in the space-time reference comprises at least an earth center of mass coordinate system, a moon center of mass coordinate system, a planet center of mass coordinate system, a sun ecliptic coordinate system, a spacecraft body coordinate system, and a sensor coordinate system.

3. The simulation system of claim 1, wherein, The method for generating moon surface multi-scale raster data by aligning and multi-level dividing remote sensing data and image data comprises the following steps: Digital orthophoto image data is superimposed on a digital elevation model describing spatial distribution of moon landform morphology, and moon surface multi-scale raster terrain data is obtained through coordinate registration and terrain and map hierarchical slicing.

4. The simulation system of claim 1, wherein, The moon surface multi-scale raster data is loaded in real time by a geographic information system data management and streaming plug-in.

5. The simulation system of any one of claims 1 to 4, wherein, The method for modeling moon surface illumination, starry sky background, ground surface material, topographic features, and moon dust distribution comprises the following steps: Positions of stars, the sun, planets, and the moon are obtained, and a planet visualized environment model is built and a starry sky background is simulated based on the positions. Moon surface illumination and shadow are simulated based on relative positions of the sun and the moon, and real moon surface material and topographic features are reflected in real time according to simulation time and space position. A space envelope model of a particle group is built based on moon dust particle simulation data, and is used for realizing scene modeling and visualized simulation of plume and moon dust characteristics.

6. The simulation system of claim 5, wherein, The lunar dust particle simulation data includes spatial position, size, density and mass of the lunar dust particle.

7. The simulation system of any one of claims 1 to 4, wherein, The method for providing data for the sensor comprises the following steps: The sensor comprises visible light imaging, three-dimensional laser imaging and speed and distance measurement type sensor. A three-dimensional digital model of the detector body is established, and the required sensor model is called according to the model configuration, and the installation position, component parameters and working mode of each sensor are initialized according to the task requirement. According to the sensor input interface, the terrain, image, height, slant range and reflection characteristics of the specified field of view or direction are called to provide true value data for the sensor model measurement simulation.

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