Digital lunar surface generation method for soft landing simulation of detector

Abstract

The invention discloses a digital lunar surface generation method for soft landing simulation of a detector, which relates to the technical field of digital lunar surface generation, and comprises the following steps: determining a moon standard impact crater model and a standard rock model based on the terrain type and terrain area of a soft landing area of the detector, and obtaining the minimum value and the maximum value of the impact crater and the rock diameter; the total number of impact pits and rocks in the soft landing area of the detector is obtained; the random coordinates of the impact craters and the rocks corresponding to the diameters of the impact craters and the rocks are circularly obtained, the random terrain of the moon impact craters and the random terrain of the moon rocks are obtained respectively, and then the random digital lunar surface containing the impact craters and the rocks is obtained. Therefore, by adopting the digital lunar surface generation method for soft landing simulation of the detector, the digital lunar surface terrain can be quickly generated according to the actual terrain parameters, the flexibility is high, and accurate terrain data is provided for verification simulation.

Description

Technical Field

[0001] The present invention relates to the technical field of digital lunar surface generation, and in particular to a digital lunar surface generation method for probe soft landing simulation. Background Art

[0002] During the soft landing of the probe, in order to fully verify the rationality of the landing mechanism plan, in addition to conducting corresponding ground simulation verification tests and taking dynamic analysis to obtain some dynamic characteristics, it is also necessary to conduct numerical simulation of various landing conditions according to the initial landing conditions and lunar surface characteristics to study the landing stability of the landing buffer mechanism.

[0003] Landing stability research is an important task in the probe development phase. Due to the complexity and uncertainty of lunar surface conditions, the pits and protrusions on the lunar surface have a great influence on stable landing. It is difficult for general dynamic analysis to fully simulate the landing conditions of all lunar surface conditions. Especially when the lunar surface conditions are relatively severe (there are large pits or protrusions), the probe stability is worse. However, the probability of such conditions occurring is extremely small, but it cannot be ignored for probes with extremely high reliability requirements.

[0004] During the soft landing of the probe on the moon, the probe's foot pad will contact and collide with the lunar surface. In order to judge the contact and collision process between the probe's foot pad and the lunar surface, a lunar topography map with a resolution smaller than the geometric feature size of the foot pad is required, that is, the resolution of the lunar topography map is required to be in the centimeter level. This digital lunar surface generation technology is different from the usual lunar topography simulation technology. Compared with the traditional sand table manufacturing method, the traditional sand table manufacturing method is mainly used for display and has too low accuracy to be used for landing simulation. Compared with some real-time lunar topography simulation methods generated based on optical and remote sensing data, its accuracy is higher, but for general landing mechanism verification tests, the required technology is too complex and the cost is too high.

[0005] Therefore, there is an urgent need for a high-precision digital lunar surface generation method to provide reliable landing area data for the dynamic verification test of the probe. It has strong flexibility and can change the generated lunar surface morphology according to the actual parameters according to the landing requirements and landing areas of different probes to be verified, such as the number, diameter, and distribution of pits and protrusions on the lunar surface, to quickly provide accurate terrain data for subsequent verification simulation work. Summary of the invention

[0006] The purpose of the present invention is to provide a digital lunar surface generation method for probe soft landing simulation, which can quickly and accurately generate random terrain features including lunar impact craters and rock protrusions in the probe soft landing analysis area on the lunar surface, so as to build reliable lunar surface features for the probe's stable landing test.

[0007] To achieve the above object, the present invention provides a method for generating a digital lunar surface for probe soft landing simulation, comprising the following steps:

[0008] S1. Obtain the position parameters of the probe soft landing area, and determine the terrain type and terrain area of ​​the probe soft landing area;

[0009] S2. Determine the standard lunar impact crater model and the standard lunar rock model according to the terrain type of the probe soft landing analysis area;

[0010] S3. Determine the minimum and maximum values ​​of the diameter of the lunar crater and the diameter of the lunar rock, respectively, based on the standard lunar crater model and the standard lunar rock model;

[0011] S4. According to the diameter of the lunar crater and the diameter of the lunar rock, the number of lunar craters and lunar rocks under the corresponding diameters are determined respectively, and the total number of lunar craters and lunar rocks in the soft landing area of ​​the probe is calculated;

[0012] S5. Based on the terrain area, the random coordinates of the impact craters and rocks corresponding to the diameters of the impact craters and rocks are obtained through a random function cycle, and then the random terrain of the lunar impact craters and the random terrain of the lunar rocks are obtained respectively;

[0013] S6. Superimpose the random terrain of lunar impact craters and the random terrain of lunar rocks to obtain a random digitized lunar surface including lunar impact craters and lunar rocks.

[0014] Preferably, the function corresponding to the lunar standard crater model is:

[0015]

[0016] In the formula, (x 坑 ,y 坑 ,z 坑 ) is the three-dimensional coordinate of the lunar impact crater, and Dcrater is the diameter of the lunar impact crater;

[0017] The function corresponding to the lunar standard rock model is:

[0018]

[0019] In the formula, (x 石 ,y 石 ,z 石 ) is the three-dimensional coordinate of the lunar rock, and Dstone is the diameter of the lunar rock.

[0020] Preferably, the relationship between the number of lunar craters and the diameter of the craters is:

[0021]

[0022] The relationship between the cumulative number of lunar rocks and rock size is:

[0023] lgN 石 =-2.5883lgD 石 -3.5301, 0.04m<D 石 <0.4m;

[0024] Where N 坑 、N 石 The numbers of lunar craters and rocks, respectively.

[0025] Therefore, the present invention adopts the above-mentioned digital lunar surface generation method for probe soft landing simulation, which has the following technical effects:

[0026] (1) By using the landing area location parameters and selecting appropriate crater and rock statistical models according to the terrain type, it is possible to simulate the pits and protrusions on the lunar surface, realize the construction of lunar surface terrain features, and construct reliable lunar surface features for the stable landing test of the probe.

[0027] (2) It has strong flexibility. It can change the generated lunar surface morphology according to the actual parameters according to the landing requirements and landing areas of different probes to be verified, such as the number, diameter, and distribution of pits and protrusions on the lunar surface, and can quickly provide more accurate terrain data for its verification simulation.

[0028] The technical solution of the present invention is further described in detail below through the accompanying drawings and embodiments. BRIEF DESCRIPTION OF THE DRAWINGS

[0029] Figure 1 A flow chart of establishing a digitized lunar surface in an embodiment of a digitized lunar surface generation method for probe soft landing simulation;

[0030] Figure 2 It is a flow chart of a terrain analysis method in an embodiment of a digital lunar surface generation method for probe soft landing simulation;

[0031] Figure 3 A cross-sectional view of a standard lunar impact crater in an embodiment of a digital lunar surface generation method for probe soft landing simulation;

[0032] Figure 4 A standard lunar rock profile in an embodiment of a digital lunar surface generation method for probe soft landing simulation;

[0033] Figure 5 A random topographic map of lunar impact craters in an embodiment of a digital lunar surface generation method for probe soft landing simulation;

[0034] Figure 6A random topographic map of lunar rocks in an embodiment of a digital lunar surface generation method for probe soft landing simulation;

[0035] Figure 7 The present invention is a schematic diagram of a random digitized lunar surface in an embodiment of a digitized lunar surface generation method for probe soft landing simulation. DETAILED DESCRIPTION

[0036] The present invention can be explained in more detail by the following examples. The purpose of disclosing the present invention is to protect all changes and improvements within the scope of the present invention. The present invention is not limited to the following examples.

[0037] In the existing stable landing analysis of probes, due to the complexity and uncertainty of lunar surface conditions, the pits and protrusions on the surface have a great impact on stable landing, making it difficult for subsequent dynamic analysis to fully simulate the landing conditions of all lunar surface conditions. Based on this, the present invention provides a digital lunar surface generation method for probe soft landing simulation, such as Figure 1 As shown, the following steps are included:

[0038] S1. Obtain the position parameters of the probe's soft landing area, and determine the terrain type and area of ​​the probe's soft landing area, so as to analyze the distribution of pits and protrusions in the probe's soft landing area, such as Figure 2 shown.

[0039] S2. Since the impact crater is mainly composed of the bottom and the lip, in order to facilitate the calculation of the shape of the typical crater, it is simplified to obtain the lunar standard impact crater model. The corresponding standard lunar impact crater profile is as follows: Figure 3 As shown, the corresponding function is:

[0040]

[0041] In the formula, (x 坑 ,y 坑 ,z 坑 ) is the three-dimensional coordinate of the lunar impact crater, and Dcrater is the diameter of the lunar impact crater.

[0042] Since the diameter and shape of the rock cover a wide range, the ratio of the minimum scale to the maximum scale of the standard lunar rock shape is between 0.5 and 1, the surface is circular or rectangular, and there may be pits, weathering or blistering. The standard height is equal to half of the diameter. In this embodiment, an ideal parabola is used as the standard rock model, and the corresponding standard rock model cross-section is as follows: Figure 4 As shown, the corresponding function is:

[0043]

[0044] In the formula, (x 石,y 石 ,z 石 ) is the three-dimensional coordinate of the lunar rock, and Dstone is the diameter of the lunar rock.

[0045] Since the probe's soft landing location is in a flat lunar sea area, it meets the standard lunar crater model. Therefore, through the determined standard lunar impact crater model and standard lunar rock model, it is possible to simulate the pits and raised terrain on the lunar surface, providing a theoretical basis for the construction of a digital lunar surface.

[0046] S3. According to the determined standard lunar impact crater model and standard lunar rock model, the minimum and maximum values ​​of the lunar impact crater diameter and the lunar rock diameter are determined respectively, and several groups of lunar impact crater and lunar rock diameters are generated by random algorithm.

[0047] In this embodiment, lunar impact craters can be divided into different categories according to their size, such as fresh craters, young craters, mature craters, and old craters. For each category, a set of values ​​is generated by linear interpolation within the range of the maximum and minimum diameters of lunar impact craters as the possible diameters of a certain category, which is used to determine the distribution of lunar impact craters. The method for determining the distribution of lunar rocks is basically the same as the operation of lunar impact craters.

[0048] S4. According to the generated diameters of the lunar craters and lunar rocks, the corresponding numbers of craters and rocks are determined respectively, and the total number of lunar craters and lunar rocks in the soft landing area of ​​the probe is calculated.

[0049] The number of lunar craters per square kilometer on the lunar surface is inversely proportional to its diameter, that is, the smaller the diameter of the ring structure, the denser its distribution. 坑 The relationship between its diameter is:

[0050]

[0051] According to the distribution of rocks on the lunar surface, the cumulative number of lunar rocks in the smooth lunar sea area can be obtained. 石 The relationship with its diameter satisfies:

[0052] lgN 石 =-2.5883lgD 石 -3.5301, 0.04m<D 石 <0.4m.

[0053] S5. Based on the terrain type and terrain area of ​​the probe soft landing area, the random coordinates of the impact craters and rocks corresponding to the diameters of the impact craters and rocks are obtained cyclically, so as to obtain the random terrain of the lunar impact craters and the random terrain of the lunar rocks, respectively, such as Figure 5 and Figure 6shown.

[0054] In this embodiment, the random coordinates of the lunar craters and lunar rocks are generated using the rand function, and based on the obtained terrain area, the generated random numbers are multiplied by the terrain area to convert them into coordinate values ​​proportional to the terrain area, thereby simulating the distribution of lunar craters and lunar rocks in the soft landing area of ​​the probe.

[0055] S6. Superimpose the random terrain of lunar impact craters and the random terrain of lunar rocks to obtain a random digitized lunar surface containing impact craters and rocks, that is, generate a terrain map of the probe soft landing area, such as Figure 7 shown.

[0056] Therefore, the present invention adopts the above-mentioned digital lunar surface generation method for probe soft landing simulation, which can quickly and accurately generate random terrain features containing lunar impact craters and rock protrusions in the probe soft landing analysis area on the lunar surface, thereby constructing reliable lunar surface features for the probe's stable landing test and facilitating subsequent related research on analyzing the probe's landing stability.

[0057] Finally, it should be noted that the above embodiments are only used to illustrate the technical solution of the present invention rather than to limit it. Although the present invention has been described in detail with reference to the preferred embodiments, those skilled in the art should understand that they can still modify or replace the technical solution of the present invention with equivalents, and these modifications or equivalent replacements cannot cause the modified technical solution to deviate from the spirit and scope of the technical solution of the present invention.

Claims

1. A digital lunar surface generation method for probe soft landing simulation, characterized in that: The following steps are involved: S1. Obtain the position parameters of the probe soft landing area, and determine the terrain type and terrain area of ​​the probe soft landing area; S2. Determine the standard lunar impact crater model and the standard lunar rock model according to the terrain type of the probe soft landing analysis area; S3. Determine the minimum and maximum values ​​of the diameter of the lunar crater and the diameter of the lunar rock, respectively, based on the standard lunar crater model and the standard lunar rock model; S4. According to the diameter of the lunar crater and the diameter of the lunar rock, the number of lunar craters and lunar rocks under the corresponding diameters are determined respectively, and the total number of lunar craters and lunar rocks in the soft landing area of ​​the probe is calculated; S5. Based on the terrain area, the random coordinates of the impact craters and rocks corresponding to the diameters of the impact craters and rocks are obtained through a random function cycle, and then the random terrain of the lunar impact craters and the random terrain of the lunar rocks are obtained respectively; S6. Superimpose the random terrain of lunar impact craters and the random terrain of lunar rocks to obtain a random digitized lunar surface including lunar impact craters and lunar rocks.

2. The method for generating a digital lunar surface for probe soft landing simulation according to claim 1, characterized in that: The function corresponding to the lunar standard crater model is: In the formula, (x 坑 ,y 坑 ,z 坑 ) is the three-dimensional coordinate of the lunar impact crater, and D is the diameter of the lunar impact crater; The function corresponding to the lunar standard rock model is: In the formula, (x 石 ,y 石 ,z 石 ) is the three-dimensional coordinate of the lunar rock, and Dstone is the diameter of the lunar rock.

3. The method for generating a digital lunar surface for probe soft landing simulation according to claim 1, characterized in that: The relationship between the number of lunar craters and their diameter is: The relationship between the cumulative number of lunar rocks and rock size is: lgN 石 =-2.5883lgD 石 -3.5301,0.04m<D 石 <0.4m Where N 坑 、N 石 The numbers of lunar craters and rocks, respectively.

Images