A method for manufacturing and testing a rubble pile asteroid simulator

Abstract

This invention relates to the field of asteroid simulation technology, and discloses a method for manufacturing and testing a rubble pile asteroid simulation. The method includes: mixing raw material powder with magnetic powder and placing the mixture in a stirring device for wetting; controlling the rotation of the stirring device to obtain multiple core-shaped particles with different diameters; applying an adhesive to the surface of the core-shaped particles and then bonding and fixing the particles to form spherical particles; and subjecting the spherical particles to high-temperature hardening to obtain the rubble pile asteroid simulation. Compared to existing computer simulation technologies for rubble pile asteroids, which suffer from simplified particle interaction models, difficulties in experimental verification, high parameter uncertainty, and limited computational resources, the manufacturing method of this application, by mixing raw material powder with magnetic powder and processing it through a special process, can realistically reproduce the physical properties of an asteroid and can be directly used in laboratory experiments to enhance verification capabilities.

Description

Technical Field

[0001] This invention relates to the field of asteroid simulation technology, specifically to a method for manufacturing and testing a rubble pile asteroid simulation. Background Technology

[0002] Currently, researchers primarily study debris-pile asteroids using computer modeling and numerical simulation. Commonly used methods include the Discrete Element Method (DEM), Smoothed Particle Hydrodynamics (SPH), and Finite Element Analysis (FEA). These methods construct mathematical models that incorporate physical parameters such as solar gravity, planetary perturbations, and particle interactions, enabling them to simulate, to a certain extent, the asteroid's trajectory, collision process, and internal structural changes. For example, in simulating the disintegration process of an asteroid after an impact, the Discrete Element Method can visually represent the ejection, migration, and re-accumulation of particles.

[0003] However, existing research methods have significant limitations. Computer simulations rely on numerous assumptions and simplifications, such as reducing particle interactions to rigid collisions and neglecting weak but crucial forces like van der Waals forces and electrostatic forces. Furthermore, model parameters (such as particle friction coefficients and porosity distribution) are difficult to obtain accurately from observational data, leading to discrepancies between simulation results and actual conditions.

[0004] Currently, there is no mature method for manufacturing simulated rubble pile asteroids. The lack of physical simulated objects makes it impossible for researchers to verify the accuracy of computer models through experimental means, and makes it difficult to intuitively observe the response characteristics of asteroids in real physical environments.

[0005] Therefore, existing technologies still need to be improved and developed. Summary of the Invention

[0006] In view of the shortcomings of the prior art, the purpose of this invention is to provide a method for manufacturing and testing a rubble pile asteroid simulator, aiming to solve the problem that most existing technologies use computer modeling and simulation of rubble pile asteroids, but there is no mature method for manufacturing rubble pile asteroid simulators.

[0007] The technical solution adopted by this invention to solve the technical problem is as follows:

[0008] A method for manufacturing and testing a rubble pile asteroid simulator, comprising:

[0009] After mixing the raw material powder with the magnetic powder, the mixture is placed in a mixing device and moistened.

[0010] The stirring device is controlled to rotate in order to obtain multiple nucleus-shaped particles with different diameters;

[0011] After applying an adhesive to the surface of the nucleus-shaped particles, the nucleus-shaped particles are bonded and fixed to form spherical particles;

[0012] The spherical particles were hardened at high temperature to obtain a rubble pile asteroid simulator.

[0013] Furthermore, the process of hardening the spherical particles at high temperature to obtain a rubble pile asteroid simulator further includes:

[0014] Magnetic powder was applied to the surface of the rubble pile asteroid simulator.

[0015] Furthermore, the step of applying an adhesive to the surface of the nucleus-shaped particles and then bonding and fixing the nucleus-shaped particles to form spherical particles includes:

[0016] The nucleus-shaped particles are held with tweezers and an adhesive is applied.

[0017] Multiple nucleus-shaped particles coated with the adhesive are randomly placed into a pre-set mold until the entire mold is filled.

[0018] Furthermore, the step of randomly placing multiple nucleus-shaped particles coated with the adhesive into a preset mold until the entire mold is filled includes:

[0019] When multiple nucleus-shaped particles coated with the binder are randomly placed into the preset mold, and the raw material powder is sprinkled in, the dust around the rubble asteroid is simulated.

[0020] Furthermore, the raw material powder is a powder obtained by grinding a meteorite sample into micron-sized particles.

[0021] Furthermore, the step of controlling the stirring device to rotate to obtain multiple nucleus-shaped particles with different diameters then includes:

[0022] The diameter range of the nuclei is preset, and multiple nuclei are screened to select those that meet the criteria.

[0023] Furthermore, the preset diameter range of the nuclei and the screening of multiple nuclei to select those that meet the criteria include:

[0024] When the diameter of the nucleus-like particles reaches the specified diameter range, an adhesive is applied to the surface of the nucleus-like particles;

[0025] When the diameter of the nucleus-shaped particles does not reach the specified diameter range, the nucleus-shaped particles are placed in a grinder and ground into raw material powder.

[0026] Furthermore, when the diameter of the nucleus-like particles reaches the specified diameter range, applying an adhesive to the surface of the nucleus-like particles includes:

[0027] Multiple nuclei-like particles from the same batch were selected, and the average moisture content of each nuclei-like particle was measured.

[0028] When the core-shaped particles meet the preset range of average moisture content, an adhesive is applied to the surface of the core-shaped particles;

[0029] When the nucleus-shaped particles do not meet the preset range of average moisture content, the nucleus-shaped particles are crushed and used as the raw material powder.

[0030] A method for testing a rubble pile asteroid simulator, comprising a rubble pile asteroid simulator manufactured based on the above-described method for manufacturing and testing a rubble pile asteroid simulator, including:

[0031] Multiple free-fall experiments were conducted on the aforementioned rubble pile asteroid simulator, and the number of core-shaped particles detached was recorded on each experiment.

[0032] The bonding failure rate of the rubble pile asteroid simulator was calculated based on the number of core particles detached in multiple instances.

[0033] The hardening strength of the rubble pile asteroid simulant with acceptable bonding failure rate was measured.

[0034] The hysteresis loop of the rubble pile asteroid simulator that has passed the hardening strength test is measured to determine whether the rubble pile asteroid simulator meets the requirements.

[0035] Furthermore, the measurement of the hysteresis loop of the rubble pile asteroid simulator with qualified hardening strength, and the determination of whether the rubble pile asteroid simulator meets the requirements, includes:

[0036] Measure the perimeter and cross-sectional area of ​​the rubble pile asteroid simulator;

[0037] The rubble pile asteroid simulator was placed in an alternating magnetic field, different currents were input into the alternating magnetic field, and the hysteresis loop measurement was completed.

[0038] Based on the parameters of the hysteresis loop, the distribution of magnetic powder and the level of magnetization within the rubble pile asteroid simulator are determined, leading to a conclusion as to whether the rubble pile asteroid simulator is qualified.

[0039] Compared with the prior art, the beneficial effects of the present invention are:

[0040] In this invention, raw material powder and magnetic powder are mixed and placed in a stirring device for wetting; the stirring device is controlled to rotate to obtain multiple core-shaped particles with different diameters; after applying an adhesive to the surface of the core-shaped particles, the particles are bonded and fixed to form spherical particles; the spherical particles are then hardened at high temperature to obtain a simulated asteroid impact pile. Compared with existing computer simulation technologies for asteroid impact piles, which suffer from problems such as simplified particle interaction models, difficulty in experimental verification, high parameter uncertainty, and limited computing resources, the manufacturing method of this application, by mixing raw material powder and magnetic powder and processing them through a special process, can realistically reproduce the physical properties of an asteroid, directly enhance verification capabilities in laboratory experiments, and also allows for flexible adjustment of key parameters, overcoming computing resource bottlenecks and rapidly testing various operating conditions. Attached Figure Description

[0041] Figure 1 This is a flowchart illustrating the manufacturing method of the asteroid simulator based on a rubble pile according to the present invention.

[0042] Figure 2 This is a flowchart of the testing method for the rubble pile asteroid simulator of the present invention.

[0043] Figure 3 This is a hysteresis loop test diagram of the asteroid simulant of the rubble pile of the present invention.

[0044] Figure 4 This is a schematic diagram illustrating the hysteresis loop test connection principle of the asteroid simulator based on a rubble pile in this invention.

[0045] The objectives, features, and advantages of this invention will be further explained in conjunction with the embodiments and with reference to the accompanying drawings. Detailed Implementation

[0046] To make the objectives, technical solutions, and effects of this invention clearer and more explicit, the invention will be further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative of the invention and are not intended to limit the invention.

[0047] In the description of this invention, it should be understood that the terms "center," "longitudinal," "lateral," "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "top," "bottom," "inner," and "outer," etc., indicating orientation or positional relationships based on the orientation or positional relationships shown in the accompanying drawings, are only for the convenience of describing the invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of the invention. 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 indicated technical features. Thus, a feature defined with "first" or "second" may explicitly or implicitly include one or more of that feature. In the description of this invention, unless otherwise stated, "a plurality of" means two or more.

[0048] In the description of this invention, it should be noted that, unless otherwise explicitly specified and limited, the terms "installation," "connection," and "linking" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; and they can refer to the internal connection of two components. Those skilled in the art can understand the specific meaning of the above terms in this invention based on the specific circumstances.

[0049] In view of the shortcomings of the prior art, this embodiment provides a method for manufacturing and testing a rubble pile asteroid simulator, which can be referred to as follows:

[0050] As attached Figure 1 As shown, a method for manufacturing a rubble pile asteroid simulator includes the following steps:

[0051] Step S100: Mix the raw material powder and magnetic powder and place them in a mixing device for wetting.

[0052] The process of preparing a rubble pile asteroid simulator begins with meticulous preparation of the necessary materials. The selected powdered raw materials must be rigorously screened based on the specific characteristics of the simulated asteroid and the experimental requirements. For example, if simulating an asteroid rich in a certain mineral, the raw materials should contain the corresponding mineral powder to facilitate subsequent experiments and observations. Magnetic powder is also carefully selected, with parameters such as magnetic strength and particle size meeting specific experimental needs. The addition of magnetic powder aims to impart certain magnetic characteristics to the simulator to simulate the magnetic field influences an asteroid might experience in the cosmic environment.

[0053] Precisely weighed powdered raw materials are placed together with magnetic powder into the turntable of the mixing equipment. This mixing equipment features a uniquely designed turntable with an optimized internal structure, providing excellent material load-bearing capacity and mixing adaptability. The mixing equipment can be implemented using existing technology. The turntable surface typically undergoes a special anti-slip and wear-resistant treatment to prevent material slippage during subsequent mixing, ensuring uniform mixing and extending the equipment's lifespan. When placing the materials, it is essential to ensure they are evenly distributed on the turntable, avoiding localized accumulation or gaps, thus laying the foundation for efficient subsequent mixing.

[0054] After the raw materials and magnetic powder are placed in the turntable, the next step is to spray water. The water spraying device is precisely connected to the mixing equipment, enabling it to evenly spray water onto the turntable according to the preset flow rate and spray range. The water spraying device is existing technology. The water used must be purified to remove impurities and microorganisms to prevent contamination of the raw materials and affecting the performance of the simulated material. During the water spraying process, the wetness of the material is closely observed, and the spraying time and amount are controlled to ensure that the material is adequately wetted. The control of the wetness is crucial. If too little water is sprayed, the material cannot bind sufficiently, which is not conducive to the subsequent particle formation; if too much water is sprayed, the material will become too viscous, affecting the mixing effect and the particle forming quality.

[0055] In this embodiment, the raw material powder is a meteorite sample ground into micron-sized powder. To simulate common carbonaceous asteroids (C-type asteroids), silica-rich asteroids (S-type asteroids), and metal-rich asteroids (M-type asteroids), carbonaceous chondrites (CI and CM types), stony meteorites with high silicate mineral content, and iron meteorites with high iron-nickel content can be selected, respectively. The raw material powder is made by grinding the meteorite sample into micron-sized powder, and the magnetic powder is also selected as micron-sized particle powder, which can be uniformly ground using a laboratory planetary ball mill. The mixing ratio of raw material powder and magnetic powder follows the principle of "raw material powder as the main component and magnetic powder as the auxiliary component," and the appropriate mixing ratio is dynamically adjusted according to the requirements.

[0056] Step S200: Control the stirring device to rotate to obtain multiple nucleus-shaped particles with different diameters.

[0057] Once the material is wetted to the ideal state, the mixing equipment is started. Equipped with a high-performance drive motor, the mixing equipment provides stable and adjustable rotational power to the turntable. As the turntable rotates at high speed, the material begins to tumble and mix under the combined action of centrifugal force, friction, and the mixing blades. During this process, the powdery material gradually aggregates and binds, forming core-like particles of varying sizes. By precisely controlling parameters such as the rotational speed, mixing time, and initial material ratio of the mixing equipment, the diameter distribution of the core-like particles can be effectively regulated. For example, higher rotational speeds and longer mixing times generally promote the formation of larger diameter core-like particles, while lower speeds and shorter times are more conducive to the formation of smaller diameter particles. During the mixing process, the particle formation can be observed in real-time using monitoring equipment, allowing for timely adjustments to the mixing parameters.

[0058] Specifically, in one implementation of this embodiment, step S200 includes the following steps:

[0059] Step S210: Preset the diameter range of the nuclei and screen multiple nuclei to select those that meet the criteria.

[0060] In this embodiment, when presetting the diameter range of nuclei and screening, the particle size range needs to be designed based on the measured data of the target asteroid or experimental requirements. A multi-level screening system combining vibration sieving and image recognition sorting is adopted. Unqualified particles are removed by vibration frequency, amplitude and machine learning algorithms to ensure the purity of each particle size range. The mixing ratio of particles of different sizes is optimized according to the porosity inversion results of the real asteroid to construct a simulation that highly fits the particle size distribution and porosity characteristics of the real asteroid, providing a highly controllable experimental sample for related research.

[0061] Specifically, in one implementation of this embodiment, step S210 includes the following steps:

[0062] Step S211: When the diameter of the nucleus-shaped particle reaches the specified diameter range, an adhesive is applied to the surface of the nucleus-shaped particle.

[0063] Step S212: When the diameter of the nucleus-shaped particles reaches the specified diameter range, the nucleus-shaped particles are placed in a grinder and ground into raw material powder.

[0064] In this embodiment, the screening process for the diameter of nucleus particles involves real-time monitoring of particle size using a precise particle size detection device. When the diameter of a nucleus particle is detected to be within a preset target range (e.g., 0.5-5 mm), it is deemed qualified and proceeds to the next preparation process. If the diameter exceeds the allowable deviation (e.g., greater than 5 mm or less than 0.5 mm), a sorting device is automatically triggered to transport unqualified particles to a grinding mill. The grinding mill employs a planetary ball milling process to refine large-diameter particles to the initial raw material powder particle size, allowing them to re-participate in the mixing process. The advantages of this closed-loop processing method are that it ensures the consistency of particle size participating in subsequent molding steps through precise screening, improving the similarity between the simulated structure and the real asteroid; it also reduces raw material waste and lowers preparation costs through a recycling mechanism; and it avoids unqualified particles affecting the physical properties of the final simulated object, ensuring the reliability and repeatability of experimental results.

[0065] Specifically, in one implementation of this embodiment, the following steps are included after step S211:

[0066] Step S211-A: Select multiple nucleus-shaped particles from the same batch and measure the average moisture content of each nucleus-shaped particle;

[0067] Step S211-B: When the core-shaped particles meet the preset range of the average moisture content, an adhesive is applied to the surface of the core-shaped particles.

[0068] Step S211-C: When the nucleus-shaped particles do not meet the preset range of the average moisture content, the nucleus-shaped particles are crushed and used as the raw material powder.

[0069] In this embodiment, several core-shaped particles of different sizes from the same batch of manufacturing processes, but without binder treatment, are selected as test particles. At room temperature, the mass m1 of the test particles of the same size is first weighed, then dried, and finally weighed again (m2). The percentage of the mass difference m1-m2 before and after heating to the mass m1 before heating is calculated, which is the average moisture content α of the test particles at that particle size; the formula is as follows:

[0070] ;

[0071] The average moisture content of all different particle sizes was measured in this manner, where the different particle sizes needed to cover all particle sizes of the simulant.

[0072] If the nucleus-shaped particles meet the preset range of average moisture content, the process proceeds to the next step; if the nucleus-shaped particles do not meet the preset range of average moisture content, the nucleus-shaped particles are crushed and used as raw material powder.

[0073] Step S300: After applying an adhesive to the surface of the nucleus-shaped particles, the nucleus-shaped particles are bonded and fixed to form spherical particles.

[0074] After the core-shaped particles are formed, they are removed from the turntable of the mixing equipment and proceed to the binder application stage. The selected binder has excellent adhesion and curing properties, playing a crucial bonding role in the simulation molding process and ensuring a tight bond between all parts. The binder can be applied using professional spraying equipment or manual application tools, ensuring a uniform layer of binder covers the surface of the core-shaped particles. After application, these binder-coated core-shaped particles are quickly placed into a specially designed ellipsoidal mold. This ellipsoidal mold is made of high-strength, high-temperature-resistant, and smooth-surfaced material, and its internal shape is precisely designed to guide the core-shaped particles for further shaping within the mold, ultimately forming particles that are close to ideal spherical shapes. When placing the particles, attention must be paid to their distribution and arrangement within the mold to avoid overlapping or compression deformation, ensuring that each particle is fully shaped within the mold.

[0075] Specifically, in one implementation of this embodiment, step S300 includes the following steps:

[0076] Step S310: Hold the nucleus-shaped particles with tweezers and apply an adhesive;

[0077] Step S320: Randomly place multiple nucleus-shaped particles coated with the adhesive into a preset mold until the entire mold is filled.

[0078] In this embodiment, the core-shaped particles are first held with tweezers and an adhesive is applied to their surface. Then, the core-shaped particles coated with adhesive are randomly filled into the mold using a vibration feeding method, filling the entire mold. As more and more particles accumulate loosely together under the action of gravity, different degrees of bonding effects are produced between the particles (no bonding, just bonding, over-bonding under the action of gravity), which fully reflects the true physical state of the rubble pile asteroid.

[0079] Specifically, in one implementation of this embodiment, step S320 includes the following steps:

[0080] Step S321: When randomly placing multiple nuclei-shaped particles coated with the adhesive into the preset mold, the raw material powder is sprinkled in to simulate the dust around a rubble asteroid.

[0081] In this embodiment, the rubble asteroid is composed of rocks and dust, which are loosely aggregated under the influence of gravity. The fabricated spherical particles can be used to simulate rocks, and raw material powder can be randomly sprinkled in during the bonding and shaping process to simulate dust.

[0082] By randomly introducing raw material powder between spherical particles in a simulated rubble pile asteroid, the "rock-dust" binary structure of a rubble pile asteroid can be accurately reproduced. The spherical particles simulate dense rock fragments, while the raw material powder simulates loose dust material on the asteroid's surface and in its gaps. This method allows the powder to naturally fill the gaps between particles through gravity, forming a loose aggregate state consistent with real asteroids without the need for additional bonding processes. This simplifies the preparation process and allows for flexible control of the porosity, surface roughness, and overall density of the simulated material by adjusting the powder particle size and the proportion of powder added. It realistically reflects the dust aggregation characteristics of asteroids caused by collisions and weathering in the cosmic environment, providing a more realistic experimental model for studying the migration of material on the asteroid surface, impact response, and dust dynamics.

[0083] Step S400: The spherical particles are hardened at high temperature to obtain a rubble pile asteroid simulation.

[0084] An ellipsoidal mold containing core-shaped particles coated with binder is placed in a specific environment and left to stand for a preset time. During this time, the binder gradually takes effect, making the bonds between the particles tighter and initially curing the material. After the preset time, the mold is opened, the spherical particles are removed, and transferred to a high-temperature curing device. The high-temperature curing device provides a stable and precisely controllable high-temperature environment. Based on the material properties of the simulated object and experimental requirements, the temperature is raised to a specific high temperature value and maintained for a period of time. Under high temperature, the internal components of the spherical particles undergo physical and chemical changes, the binder further solidifies, the material structure is strengthened, and ultimately a rubble asteroid simulated object with a certain strength and stability is formed. The temperature, time, and other parameters of high-temperature curing have a significant impact on the final performance of the simulated object. For example, excessively high temperatures or excessively long times may cause defects such as cracking and deformation, while excessively low temperatures or excessively short times will not achieve the expected curing effect. Therefore, the operating parameters of the high-temperature curing device must be strictly monitored during operation to ensure that the quality of the simulated object meets the requirements.

[0085] At high temperatures, certain elements present in the raw materials expand, forming pores, while a hard vitrified layer forms on the surface of the spherical particles. This process ultimately produces a simulated asteroid impact pile, facilitating subsequent experiments. Spherical particles of varying sizes, possessing a certain strength after sintering and hardening, can simulate gravel; sets of spherical particles randomly placed and filling a mold can simulate a gravel pile structure; and the adhesive coating between the spherical particles can simulate the van der Waals adhesion forces required to aggregate into a gravel pile structure.

[0086] Specifically, in one implementation of this embodiment, step S400 includes the following steps:

[0087] Step S410: Apply magnetic powder to the surface of the rubble pile asteroid simulator.

[0088] After creating the rubble pile asteroid simulator, magnetic powder needs to be applied to its surface to more comprehensively simulate the magnetic characteristics an asteroid might possess in a cosmic environment. The selected magnetic powder undergoes rigorous screening, ensuring its magnetic parameters, particle size, and dispersion properties meet the specific requirements of the simulation experiment. The application of magnetic powder requires extreme care, utilizing specialized tools such as a specialized spray gun or a fine brush. When using a spray gun, precise control of air pressure and powder output ensures the magnetic powder is evenly sprayed and adheres to the simulator's surface. If using a brush, skilled operators must slowly and evenly apply the powder along the surface, ensuring each area is covered with a suitable thickness of magnetic powder. This process allows the rubble pile asteroid simulator to possess a physical structure and strength similar to a real asteroid, while also exhibiting specific magnetic properties, providing a more comprehensive experimental subject for subsequent in-depth simulation studies of asteroids in magnetic field environments.

[0089] As attached Figure 2 As shown, this application also proposes a testing method for a rubble pile asteroid simulator. The rubble pile asteroid simulator manufactured based on the above-described manufacturing and testing method includes the following steps:

[0090] Step S401: Conduct multiple free-fall tests on the rubble pile asteroid simulator and record the number of core particles detached each time.

[0091] Step S402: Calculate the bonding failure rate of the rubble pile asteroid simulator based on the number of core particles detached multiple times.

[0092] Step S403: Measure the hardening strength of the rubble pile asteroid simulant with qualified bonding failure rate;

[0093] Step S404: Measure the hysteresis loop of the rubble pile asteroid simulator that has passed the hardening strength test, and determine whether the rubble pile asteroid simulator meets the requirements.

[0094] In this embodiment, the rubble pile asteroid simulator is placed at appropriately increasing heights l1, l2...l1. n Let it fall freely and record the number of outer layer particles detached u in n falls. n and the number of inner layer particles detached v n Then, the simulated asteroid with rubble piles was placed at progressively increasing rotational speeds ω1, ω2, ... ω n On a centrifuge, after rotating the sample around its center for a period of time, record the number of outer layer particles detached x times in n cycles. n and the number of inner layer particles detached y nFinally, the number of outer layer particles detached, u, is calculated n times. n Number of inner layer particles detached (v) n Number of outer layer particles peeled off x n and the number of inner layer particles detached y n The sum of these values, expressed as a percentage of the total number of particles A in the 2n known simulated objects, represents the cohesion failure rate β of the simulated asteroid rubble pile. The formula is as follows:

[0095] ;

[0096] The bonding failure rate β obtained by the above formula is used to determine whether the rubble pile asteroid simulator meets the requirements. If the rubble pile asteroid simulator meets the requirements, it will proceed to the next performance test; if the rubble pile asteroid simulator does not meet the requirements, it will be crushed into raw material powder.

[0097] From the particles detached in the previous process, n particles are selected. The surface of one of these particles is first ground smooth. A rigid indenter with a regular shape is then pressed into the surface of the smoothed particle under gradually increasing external force. Once the external force reaches a predetermined peak, it is gradually released. During this loading and unloading process, high-precision load-displacement testing technology is used to simultaneously record the indenter displacement h and the load P borne by the indenter. Analyzing the obtained Ph curve yields the average hardness H1 of the particle. Nanoindentation technology is then used to measure the corresponding average hardness H of the n particles in this manner. n Calculate the average hardness H of the n particles. n The average value of γ is the hardening strength γ of the simulated material. The formula is as follows:

[0098] ;

[0099] If no particles are detached from the previous process, the particles in the simulant are considered to be completely bonded (an idealized situation with an extremely low probability). A flat test area needs to be defined, the rebound hammer installed on the surface of the simulant to be tested, and the button pressed to allow the impact pin to fall freely and impact the test area surface. The height of the rebound pin is observed and recorded. Based on the rebound value and the calibration curve of the concrete, the hardening strength γ of the simulant is determined with reference to the concrete strength.

[0100] The hardening strength γ obtained by the above formula is used to determine whether the rubble pile asteroid simulator meets the requirements. If the rubble pile asteroid simulator meets the requirements, it will proceed to the next performance test; if the rubble pile asteroid simulator does not meet the requirements, it will be crushed into raw material powder.

[0101] Specifically, in one implementation of this embodiment, step S404 includes the following steps:

[0102] Step S404-A: Measure the perimeter and cross-sectional area of ​​the rubble pile asteroid simulator;

[0103] Step S404-B: Place the rubble pile asteroid simulator into an alternating magnetic field, input different currents into the alternating magnetic field, and complete the hysteresis loop measurement.

[0104] Step S404-C: Based on the parameters of the hysteresis loop, determine the distribution of magnetic powder and the magnetization level within the rubble pile asteroid simulator, and conclude whether the rubble pile asteroid simulator is qualified.

[0105] In this embodiment, a hysteresis loop test is performed on a rubble pile asteroid simulant that has passed the hardening strength test. A primary coil (excitation coil) is selected, wound with multi-strand fine wire to reduce the skin effect, and the number of turns N1 needs to be large enough to reduce the required current (e.g., 100-500 turns). A secondary coil (induction coil) is selected, wound tightly and uniformly, with the number of turns matched to the primary coil to ensure the signal-to-noise ratio. The primary coil is connected to an adjustable DC power supply and an ammeter, while the secondary coil is connected to an integrator and a data acquisition system. The output current of the high-current DC power supply can reach 10-50A, and the high-precision integrator is used to integrate the induced voltage of the secondary coil.

[0106] First, measure the perimeter L and cross-sectional area A of the rubble pile asteroid simulator. Then, place the rubble pile asteroid simulator in an alternating magnetic field and slowly decrease the current I to zero. Starting from I=0, gradually increase the current to saturation, recording the current I and the induced voltage V(t) of the secondary coil at each point, and calculate the corresponding H and B. After reaching saturation, gradually decrease the current to 0, then increase it in the opposite direction to negative saturation, completing the hysteresis loop measurement (e.g., Figure 1 (As shown). The formulas for calculating H and B are as follows:

[0107] ;

[0108] Where H is the magnetic field strength, N1 is the number of turns of the primary coil (excitation coil), I is the current through the primary coil, and L is the perimeter of the rubble pile asteroid simulator;

[0109] ;

[0110] Where B is the magnetic induction intensity, N2 is the number of turns of the secondary coil (induction coil), A is the cross-sectional area of ​​the rubble pile asteroid simulator, and t1 and t2 are the integration time intervals, representing the start and end time points of the integration of the induced voltage V(t).

[0111] The magnetic induction of the simulated object can be determined by the hysteresis loop, and the distribution of magnetic powder and magnetization level inside the object can be analyzed.

[0112] As attached Figure 3and attached Figure 4 As shown, the horizontal axis H represents the magnetic field strength (related to the current source), and the vertical axis B represents the magnetic flux density (related to the material and the magnetic field strength). At point O, H=0, B=0, which is a magnetically neutral state; as H increases, B also increases, until H reaches H0. s When B reaches saturation point B s This also means that when H>H s Then, if H continues to increase, B will no longer increase; when H decreases to 0, B is not 0, and B = B. r The change in B lags behind the change in H; this phenomenon is called hysteresis, and the retained B r This is called remanence; when the magnetic field direction increases in the opposite direction, H increases to -H. c At that time, B=0, H c Called coercivity, it represents the ability of a magnetic material to maintain its remanent magnetization; H increases in the opposite direction to -H. s When B reaches saturation point -B s When H decreases in the opposite direction to 0, B = -B r H increases to H c B=0; H increases to H s B=B s The curves are closed, repeating and alternating, in a continuous cycle. Figure 3 The schematic diagram is divided into upper and lower circuits, with a simulated asteroid placed in the middle. A represents an ammeter, V a voltmeter, R1 and R2 resistors, N1 and N2 coils, and C a capacitor. A simulated asteroid pile is placed between R1 and R2. The upper circuit outputs DC current, connected in series with the ammeter, leading to the primary coil N1. The current is adjusted by a controllable resistor R1. The lower circuit obtains an induced voltage through the secondary coil N2, connected in series with the voltmeter, and then passes through a basic inverting analog integrator controlled by the controllable resistor R2. The high-precision integrator includes an operational amplifier and a capacitor in the feedback path.

[0113] Based on the above principle, the hysteresis loop of a rubble pile asteroid simulation material can be effectively measured, and its internal magnetic powder distribution and magnetization level can be analyzed. When the rubble pile asteroid simulation material meets the preset range, the simulation experiment can be carried out; when the rubble pile asteroid simulation material does not meet the preset range, it is crushed into raw material powder.

[0114] The average moisture content α, bond failure rate β, hardening strength γ, hysteresis loop, and other indicators are listed as the finished product quality parameters of the simulant. If the finished product quality parameters obviously do not meet the normal experimental requirements, the finished product quality of the simulant is considered poor and it should be remade. If the finished product quality parameters meet the normal experimental requirements, various subsequent experiments can be carried out according to different experimental requirements.

[0115] Other embodiments of the invention will readily occur to those skilled in the art upon consideration of the specification and practice of the solutions disclosed herein. This invention is intended to cover any variations, uses, or adaptations of the invention that follow the general principles of the invention and include common knowledge or customary techniques in the art not disclosed herein. The specification and examples are to be considered exemplary only, and the true scope and spirit of the invention are indicated by the claims.

Claims

1. A testing method for a rubble pile asteroid simulant, characterized in that, The method for manufacturing a rubble pile asteroid simulator for testing also includes: Multiple free-fall experiments were conducted on the aforementioned rubble pile asteroid simulator, and the number of core-like particles detached was recorded on each experiment. The bonding failure rate of the rubble pile asteroid simulator was calculated based on the number of core particles detached in multiple instances. The hardening strength of the rubble pile asteroid simulant with acceptable bonding failure rate was measured. The hysteresis loop of the rubble pile asteroid simulator that has passed the hardening strength test is measured, and it is determined whether the rubble pile asteroid simulator meets the requirements. The method for manufacturing the rubble pile asteroid simulator includes: After mixing the raw material powder with the magnetic powder, the mixture is placed in a mixing device and moistened. The stirring device is controlled to rotate in order to obtain multiple nucleus-shaped particles with different diameters; After applying an adhesive to the surface of the nucleus-shaped particles, the nucleus-shaped particles are bonded and fixed to form spherical particles; The spherical particles were hardened at high temperature to obtain a rubble pile asteroid simulator.

2. The testing method for a rubble pile asteroid simulator according to claim 1, characterized in that, The process of hardening the spherical particles at high temperature to obtain a simulated asteroid in the form of a rubble pile further includes: Magnetic powder was applied to the surface of the rubble pile asteroid simulator.

3. The testing method for a rubble pile asteroid simulator according to claim 1, characterized in that, The step of applying an adhesive to the surface of the nucleus-shaped particles and then bonding and fixing the nucleus-shaped particles to form spherical particles includes: The nucleus-shaped particles are held with tweezers and an adhesive is applied. Multiple nucleus-shaped particles coated with the adhesive are randomly placed into a pre-set mold until the entire mold is filled.

4. The testing method for a rubble pile asteroid simulator according to claim 3, characterized in that, The step of randomly placing multiple core-shaped particles coated with the adhesive into a preset mold until the entire mold is filled includes: When multiple nucleus-shaped particles coated with the binder are randomly placed into the preset mold, and the raw material powder is sprinkled in, the dust around the rubble asteroid is simulated.

5. The testing method for a rubble pile asteroid simulator according to claim 1, characterized in that, The raw material powder is the powder obtained by grinding a meteorite sample into micron-sized powder.

6. The testing method for a rubble pile asteroid simulator according to claim 1, characterized in that, The process of controlling the rotation of the stirring device to obtain multiple nucleus-shaped particles with different diameters then includes: The diameter range of the nuclei is preset, and multiple nuclei are screened to select those that meet the criteria.

7. The testing method for a rubble pile asteroid simulator according to claim 6, characterized in that, The process of pre-setting the diameter range of the nuclei and screening multiple nuclei to select those that meet the criteria includes: When the diameter of the nucleus-like particles reaches the specified diameter range, an adhesive is applied to the surface of the nucleus-like particles; When the diameter of the nucleus-shaped particles does not reach the specified diameter range, the nucleus-shaped particles are placed in a grinder and ground into raw material powder.

8. The testing method for a rubble pile asteroid simulator according to claim 7, characterized in that, When the diameter of the nucleus-like particle reaches the specified diameter range, applying an adhesive to the surface of the nucleus-like particle includes: Multiple nuclei-like particles from the same batch were selected, and the average moisture content of each nuclei-like particle was measured. When the core-shaped particles meet the preset range of average moisture content, an adhesive is applied to the surface of the core-shaped particles; When the nucleus-shaped particles do not meet the preset range of average moisture content, the nucleus-shaped particles are crushed and used as the raw material powder.

9. The testing method for a rubble pile asteroid simulator according to claim 1, characterized in that, The process of measuring the hysteresis loop of the rubble pile asteroid simulator that has passed the hardening strength test and determining whether the rubble pile asteroid simulator meets the requirements includes: Measure the perimeter and cross-sectional area of ​​the rubble pile asteroid simulator; The rubble pile asteroid simulator was placed in an alternating magnetic field, different currents were input into the alternating magnetic field, and the hysteresis loop measurement was completed. Based on the parameters of the hysteresis loop, the distribution of magnetic powder and the level of magnetization within the rubble pile asteroid simulator are determined, leading to a conclusion as to whether the rubble pile asteroid simulator is qualified.

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