In-situ mechanical static sounding method for lunar soil carried by lunar rover

Abstract

The application relates to a lunar soil in-situ mechanical static sounding method carried by a lunar rover. The lunar soil in-situ mechanical static sounding method carried by the lunar rover comprises the following steps: obtaining drilling power and rotating torque by using a drilling subsystem; obtaining resistance characteristic data of lunar soil by using a mechanical sensor of a static sounding instrument; calculating shearing force generated by the static sounding instrument in shearing lunar soil by using rotating torque generated by the drilling subsystem in shearing lunar soil; obtaining shearing characteristics of the lunar soil by using a theoretical model of the rotating torque and the shearing force; and constructing a mechanical equation of penetration resistance, rotating torque and cohesion c and internal friction angle phi of the lunar soil based on the data obtained by the lunar soil in-situ mechanical static sounding system by using a computer device, so as to interpret in-situ mechanical characteristic parameters of the lunar soil. The application has the characteristics of small size, light weight, low energy consumption and intelligence, and breaks through the technical bottleneck of the vehicle-mounted static sounding instrument.

Description

Technical Field

[0001] This invention relates to the field of lunar soil mechanics detection technology. In particular, it relates to an in-situ static penetrometer method for lunar soil mechanics detection carried by a lunar rover. Background Technology

[0002] Obtaining in-situ mechanics data of lunar regolith is a prerequisite for scientific research and construction on the lunar surface. Static exploration data from the Apollo series showed that lunar regolith mechanics varies significantly across different parts of the lunar surface. The landing site of my country's manned lunar mission differs from that of the Apollo series, and the lack of comparable data necessitates a breakthrough in in-situ lunar regolith mechanics exploration, establishing my country's own in-situ lunar regolith mechanics data.

[0003] In the past, planetary exploration activities were limited by rocket carrying capacity, resulting in very limited probe size and mass, while the scientific tasks they undertook were very challenging. This led to the simplification and multi-functionality of instrument design for in-situ geological engineering testing.

[0004] The Soviet Union first determined the density and penetration resistance of the lunar regolith during its Luna 13 mission, launched in 1966. Luna 13 was equipped with a relatively simple conical penetrometer. The cone's outer shell was made of plastic. A small, upward-pointing fuel engine provided the power for the conical probe to penetrate the lunar regolith, applying approximately 65 N of force and achieving a penetration depth of about 45 mm. To process the test data, 14 simulated lunar regolith samples of different densities were used for calibration on Earth, and calculations were performed using the Berezantsev formula. Because the probe could not move, all measurements were conducted near the landing site. The mission lasted only about four days, with approximately three to five probes.

[0005] The Luna 17 mission in 1970 upgraded the Luna 13 cone penetrator by adding two symmetrical vertical blades to the probe, forming the Propeller Prop (PROP). This instrument could simultaneously perform both penetration and shearing tests, reducing the size of the test equipment and the instrument itself. The top of the instrument was hinged to the Luna 1 rover, which lowered the penetrator to the lunar surface, applied vertical pressure to press the cone-shaped probe into the lunar regolith, and then twisted 90° to complete the shearing test. The Luna 21 mission's Lunokhod 2 autonomous probe also used PROP to test the physical and mechanical properties of the lunar regolith. Lunokhod 1 and 2 traveled over 47 kilometers on the lunar surface, conducting over a thousand mechanical probes to a depth of less than 10 cm.

[0006] In 1971, the United States used the Apollo Simple Penetrator (ASP) on Apollo 14. Its working principle was similar to the Static Penetrator (SCP). The probe was a 60 cm long aluminum rod with a diameter of 0.95 cm. The experiment required manual pressing by the astronauts. Based on ground-based zero-gravity aircraft tests, the estimated pressure provided by a single-handed press was approximately 71–134 N, and by two-handed presses, approximately 134–223 N. The penetration depths achieved with one hand were 42, 44, and 52 cm, and with two-handed presses, 62, 62, and 68 cm. While the ASP was simple to operate, it required a large amount of thrust, which increased significantly with depth. This limited its applicability to loose lunar regolith near the surface. Furthermore, the uncertainty of the force applied by the astronauts during the probe's operation significantly affected the reliability of the data obtained. The Apollo 15 and 16 missions used a self-recording penetrator (SRP). Similar in operation to the ASP (asphalt-propelled penetrator), the SRP consists of a rod with a cone and a flat plate at one end. Penetration pressure is provided by the astronauts' gravity. The astronauts pressed two cones of different diameters (12.8 and 20.3 mm) into the lunar regolith. A total of 17 tests were conducted during the Apollo 15 and 16 missions, with depths ranging from 20 to 74 cm, but only 8 exceeded 20 cm.

[0007] The successful completion of lunar soil mechanical penetration tests in all current lunar exploration missions is limited by factors such as the accuracy of sensors, the level of technology, and the feasibility of engineering at the time. This results in limited exploration depth, low data accuracy, and the inability to accurately invert key mechanical parameters such as cohesion and internal friction angle.

[0008] While the Apollo manned lunar landing program sent astronauts to the moon for in-situ testing, planetary exploration has primarily relied on unmanned probes. The American Surveyor 3 and Surveyor 7 lunar probes were equipped with robotic arms and buckets, conducting static load and impact tests on the lunar surface, but unable to explore the deep lunar regolith. my country's Chang'e 5 lunar probe also featured a robotic arm and bucket, but did not specifically test the properties of the lunar regolith.

[0009] my country has not yet conducted any in-situ mechanical exploration of lunar soil using the penetrating probe method. The quantity of lunar soil samples available for macroscopic mechanical testing in my country remains relatively small (in milligrams), insufficient to meet the demand. Furthermore, the sampling process damages the structure and morphology of the lunar soil, making it difficult to accurately reflect its true mechanical properties even with large-scale ground-based macroscopic mechanical testing. Therefore, the problem of in-situ mechanical exploration of lunar soil urgently needs to be addressed. Summary of the Invention

[0010] This invention provides a static cone penetration test method for in-situ mechanics of lunar soil carried by a lunar rover, in order to solve the problem of in-situ in-orbit exploration of lunar soil mechanics.

[0011] To achieve the above objectives, this invention relates to an in-situ mechanical static cone penetration test method for lunar regolith aboard a lunar rover. The method employs an in-situ mechanical static cone penetration test system and computer equipment. The system comprises four parts: a penetrometer, a drilling subsystem, a data acquisition subsystem, and an electrical control and management subsystem. The penetrometer is used to acquire the penetration resistance during the drilling process; the drilling subsystem provides drilling power and rotational torque; the data acquisition subsystem mainly records the current and speed data of the motor, and acquires penetration resistance data, acceleration data, and attitude data; the electrical control and management subsystem supports the transmission and reception of lunar surface payload commands and the control of the exploration mission. The method includes the following steps:

[0012] The drilling subsystem is used to obtain drilling power and rotational torque, the mechanical sensors of the static cone penetrometer are used to obtain resistance characteristics data of lunar soil, and the rotational torque generated by the rotational shearing of lunar soil by the drilling subsystem is used.

[0013] Using data obtained from a lunar soil in-situ mechanical static cone penetration test system based on computer equipment, a mechanical equation F=f1(c,φ) is constructed to represent the penetration resistance F and the lunar soil cohesion c and internal friction angle φ. A mechanical equation M=f2(c,φ) is also constructed to represent the rotational torque M and the lunar soil cohesion c and internal friction angle φ. This is to interpret the in-situ mechanical property parameters of the lunar soil, which include at least the lunar soil cohesion c and internal friction angle φ.

[0014] The present invention relates to an in-situ mechanical static penetration test method for lunar soil carried by a lunar rover, which has the following advantages compared with the prior art:

[0015] Through innovative static cone penetrometer design and intelligent interpretation algorithms, precise measurements of key mechanical parameters such as lunar soil cohesion and internal friction angle have been achieved. This technical solution is characterized by its small size, lightweight design, low energy consumption, and intelligent operation, breaking through the technical bottlenecks of vehicle-mounted static cone penetrometers.

[0016] 1. A novel in-situ mechanical testing technology for lunar soil is proposed, enabling in-situ, orbital exploration of lunar soil mechanics, filling a technological gap in this field. Compared to Chang'e 5 and 6, which only conducted sampling without in-situ mechanical testing, this invention can directly obtain the true mechanical properties of lunar soil.

[0017] 2. The system's total weight is ≤3.6kg, and its total power consumption is ≤29W (static penetrometer ≤24W, electrical control management system ≤5W). Compared to traditional ground-based testing equipment, it significantly reduces size and weight, making it suitable for direct mounting on lunar rovers. Compared to previous anchor-based solutions, it eliminates the anchor fixing step, simplifies the operation process, and improves reliability.

[0018] 3. Possesses multi-mode measurement capabilities for static cone penetration and rotational shear, simultaneously acquiring the compressive and shear properties of lunar regolith, obtaining more comprehensive mechanical parameters in a single test. Through innovative structural design and mechanical models, decoupled measurement of penetration resistance and rotational torque is achieved, enabling precise acquisition of the interaction force between structural components and lunar regolith. Measurement accuracy: Penetration resistance ≤500N, nonlinear measurement error ≤2%; torque ≤4.0Nm. Attached Figure Description

[0019] Figure 1 This is a flowchart of a method for in-situ mechanical static cone penetration testing of lunar soil carried by a lunar rover, according to Embodiment 1 of the present invention.

[0020] Figure 2 This is a static penetrometer system for an in-situ mechanical static penetrometer method for lunar soil carried by a lunar rover, as described in Embodiment 1 of the present invention.

[0021] Figure 3 This is a mechanical structure diagram of a static cone penetrometer for an in-situ mechanical static cone penetrometer method for lunar soil carried by a lunar rover, according to Embodiment 1 of the present invention.

[0022] Figure 4 This is a flowchart of the static cone penetrometer system for an in-situ mechanical static cone penetrometer method for lunar soil carried by a lunar rover, according to Embodiment 1 of the present invention.

[0023] Figure 5 This is a diagram of the blade-type and plow-type drilling mechanism of the static cone penetrometer for an in-situ mechanical static cone penetrometer method for lunar soil carried by a lunar rover, according to Embodiment 1 of the present invention.

[0024] Figure 6 This is an example of the installation layout of the static cone penetrometer for an in-situ mechanical static cone penetrometer method for lunar soil carried by a lunar rover, as described in Embodiment 1 of the present invention. Detailed Implementation

[0025] The present invention will now be described in further detail 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 not intended to limit it. Furthermore, it should be noted that, for ease of description, the accompanying drawings show only the parts relevant to the present invention, and not all of the structures.

[0026] Example 1

[0027] A method for in-situ static penetrometry of lunar regolith carried by a lunar rover; please refer to [link to relevant documentation]. Figures 1-6The lunar regolith in-situ mechanical static cone penetration test (RCP) system and computer equipment were used for the test. The RCP system comprises four parts: a penetrometer, a drilling subsystem, a data acquisition subsystem, and an electrical control and management subsystem. The penetrometer is used to acquire the penetration resistance during drilling; the drilling subsystem provides drilling power and rotational torque; the data acquisition subsystem mainly records the current and speed data of the motor, and acquires penetration resistance data, acceleration data, and attitude data; the electrical control and management subsystem supports the transmission and reception of lunar surface payload commands and controls the exploration mission. The method includes the following steps:

[0028] S101 utilizes the drilling subsystem to obtain drilling power and rotational torque, uses the mechanical sensors of the static cone penetrometer to obtain data on the resistance characteristics of lunar soil, and utilizes the rotational torque generated by the rotational shearing of lunar soil by the drilling subsystem.

[0029] The resistance characteristic data includes penetration resistance, penetration time, and penetration depth.

[0030] Furthermore, the shearing characteristics of lunar soil can be obtained by calculating the shearing force generated by the static cone penetrometer shearing the lunar soil and by using a theoretical model of the rotational torque and the shearing force.

[0031] The shear characteristics of lunar soil can be obtained through existing theoretical models of the rotational torque and the shear force, and the shear characteristics are the shear strength of lunar soil.

[0032] S102 uses computer equipment to construct the mechanical equation F=f1(c,φ) based on data obtained from the lunar soil in-situ mechanical static cone penetration test system, and constructs the mechanical equation M=f2(c,φ) based on the penetration resistance F and the lunar soil cohesion c and internal friction angle φ, in order to interpret the in-situ mechanical property parameters of the lunar soil. The in-situ mechanical property parameters of the lunar soil include at least the lunar soil cohesion c and the internal friction angle φ.

[0033] like Figure 3 As shown, in this embodiment, the penetration instrument includes a probe and a mechanical sensor; the drilling subsystem includes a fixed lead screw, a drill rod, a rotating inner tube, a motor, and a protective shell. The top of the drill rod is provided with a sliding pin that engages with the fixed lead screw. The rotating inner tube is engaged with a gear driven by the motor, which drives the rotating inner tube to rotate, thereby driving the drill rod to rotate. The fixed lead screw is fixed to the top of the outer protective shell and engages with the central threaded hole at the top of the drill rod. The rotation of the drill rod is engaged with the fixed lead screw nut to cause the drill rod to change displacement on the lead screw axis.

[0034] Specifically, the composition and component dimensions are as follows: Figure 3As shown, the static cone penetrometer consists of a miniature motor, lead screw, sleeve, lead sleeve, probe rod, mechanical sensor, fasteners for connection, and cables for signal transmission. The ground anchor and push rod work together to drive the nut guide block to achieve linear movement guidance. The mechanical sensor is fixed to the inner cavity arm of the ground anchor with headless screws on its side wall. Considering the large temperature difference and irradiated vacuum environment of outer space, all components of the test load are made of hard, lightweight aluminum to avoid the influence of material deformation on mechanical parameters. The total length of the test load is 772.7 mm, of which the ground anchor rod is 600 mm long, with an inner diameter of 25 mm and an outer diameter of 30 mm; the static cone penetrometer is 220 mm long, the probe rod is 90 mm long, the probe is 37 mm long, and the probe angle is 30°.

[0035] In this embodiment, after interpreting the in-situ mechanical property parameters of lunar soil, the method further includes: based on the interpreted in-situ mechanical property parameters of lunar soil, using the Bekker bearing model to construct mathematical expressions for the mechanical property parameters and bearing capacity of lunar soil, and using the Janosi shear model to construct the correlation between the in-situ mechanical property parameters and the shear strength of lunar soil, so as to construct lunar soil bearing and shear models.

[0036] In this embodiment, specifically, the Bekker bearing capacity model is used to construct the mathematical expression of the mechanical properties and bearing capacity of lunar soil: Where P is the grounding voltage ratio. The cohesive modulus of lunar soil. Let be the lunar soil friction deformation modulus, b be the wheel width, z be the subsidence, and n be the soil deformation index. And the Janosi shear model: ,in, Let be the shear strength of the lunar soil, k be the shear modulus of the lunar soil, and c be the cohesion. Let be the internal friction angle, j be the shear displacement, and be the lunar regolith shear deformation index. Based on the above, the correlation between in-situ mechanical property parameters and lunar regolith shear strength is established to construct a lunar regolith bearing and shear model.

[0037] In this embodiment, in S101, the drilling subsystem is used to obtain drilling power and rotational torque, the mechanical sensor of the static penetrometer is used to obtain the resistance characteristics data of the lunar soil, and the rotational torque generated by the rotational shearing of the lunar soil by the drilling subsystem is used. Specifically, in S1011, after the lunar rover reaches the designated position, the electrical control management subsystem of the static penetrometer issues a static penetrometer working command, starts the motor to start working and pushes the penetrometer. The static penetrometer probe penetrates the lunar soil with the drill rod at a speed of 2 cm / min to reach the required drilling depth. At the same time, the data acquisition system collects the penetration resistance data, attitude data and acceleration data of the probe, and records the rotational speed of the drill rod and the power of the motor and feeds back to control the motor.

[0038] After the S1012 drilling mission is completed, the electrical control management subsystem will issue a motor reversal command. The motor control system will then rotate the motor in the opposite direction to retract the drill rod, terminating the exploration at that point. The lunar rover will then proceed to the next point to be explored.

[0039] Specifically, such as Figure 4 As shown, this test load employs a combined penetration and shearing approach to perform in-situ mechanical parameter testing of lunar regolith, with a probe depth of ~50cm. The workflow is as follows (…). Figure 3 Specifically, the process is as follows: After the lunar rover reaches the designated location, the payload electrical control management system of the static penetrometer issues a working command. The motor control system starts the motor to propel the penetrometer. The penetrometer probe, along with the drill rod, penetrates the lunar regolith at a speed of 2 cm / min to reach the required drilling depth. Simultaneously, it collects data on the probe's penetration resistance, attitude, and acceleration, and records the drill rod's rotational speed and the motor's power, feeding this data back to control the motor. Data transmission and storage also occur concurrently. After the drilling mission is completed, the electrical control management system issues a motor reversal command. The motor control system reverses the motor's rotation, the drill rod retracts, and the exploration at that point is terminated. The data is then returned to Earth for analysis and interpretation. The rover then proceeds with the penetrometer to the next target point for multi-point exploration.

[0040] With a lead screw pitch of 1 mm / turn and the drill pipe rotating at 20 rpm, the penetration speed is 2 cm / min. If the total penetration is 50 cm, the total penetration time is 25 min. Under normal operating conditions, the drill pipe penetration time and retraction time are both 25 min. Considering the standby warm-up time, the estimated working time for a single probe is 60 min.

[0041] The exploration mode involves the lunar rover coming to a standstill and conducting multi-point exploration along its trajectory, performing one probe after each stop. There are two operating modes: standby and active. After the rover lands, the static penetrometer (SPP) is in standby mode while the rover is searching for and determining the measurement points. In active mode, once the rover reaches the designated location, the motor drives the drill rod to drill, and the SPP probe penetrates the lunar regolith at a speed of 2 cm / min to reach the required depth. Simultaneously, the penetration resistance, acceleration, and attitude of the probe are measured and recorded, along with the motor's operating current and the drill rod's rotational speed. The drill rod rotates at 20 rpm, achieving a feed rate of 2 cm / min, with a total feed time of 25 minutes. If there are no faults, a command to stop the motor and retract (reverse) is issued after 25 minutes. During exploration, encountering lunar rocks, hard boulders, etc., is possible. Since the drill rod and SPP lack the ability to break rocks, the electrical control management system immediately issues a retraction command, stopping data acquisition. The static penetrometer enters standby mode and will resume operation once the lunar rover reaches the next probe site.

[0042] In this embodiment, S102 specifically includes:

[0043] S1021: Calculation of penetration resistance:

[0044] Calculate the initial geostress distribution of lunar soil:

[0045] (1);

[0046] in, For penetration resistance, It is the geostress related to the penetration depth, where A is the area of ​​the static cone penetrometer. It is the internal friction angle.

[0047] Calculate the vertical stress of lunar soil:

[0048] (2);

[0049] in, Let z be the density of lunar soil and z be the penetration depth. This is the gravitational acceleration on the lunar surface.

[0050] Calculate sidewall resistance:

[0051] (3);

[0052] in, For sidewall resistance, and It is a constant;

[0053] Calculate the penetration resistance of a plow-type static cone penetrometer:

[0054] (4);

[0055] The calculated parameters are: penetration depth z = 500 mm, harrowing depth h = 450 mm = 0.45 m. = 1.62 m / s², drill pipe diameter d = 26 mm, plow diameter D = 46 mm, cone angle of the penetrometer probe θ = 30°, A = 5.31 cm², μ0 = 0.6, K0 = 0.5, φ = 43°. The mechanical analysis results of the plow type are shown in Table 1, where the pull-out resistance is the sum of the side friction and the resistance.

[0056] Table 1 Mechanical Analysis of the Probe Development Scheme for the Plow-Type Static Penetrometer

[0057]

[0058] S1022: Calculation of Rotational Torque for Static Penetration Tester: Calculate the required rotational torque T when the penetration depth z is 50 cm: (5) Where F is the total penetration resistance of the static penetrometer, and the theoretical calculation value of the plow-type is 143.3 N; d = 2.6 cm is the diameter of the penetrometer; A is the shear area; D = 5 cm is the shear diameter; The internal friction angle of the lunar soil is taken as 43°. To bear the pressure on the blades at the tip of the drill pipe. Vertical stress of lunar soil (6), among which, Using lunar surface gravitational acceleration, the theoretical torque for the plowshare-like action is approximately 1.89 N·m. In this embodiment, after the penetration process, the drill pipe is retracted. The calculation process for the drill pipe's pull-out torque is as follows: substituting the pull-out force into the formula, the pull-out torque for the plowshare-like action is obtained as 0.1 N·m. 4 N·m.

[0059] This also includes: the calculation process for the pull-out moment M of the drill pipe involves substituting the pull-out force R into the formula. Thus, the pull-out torque M is obtained.

[0060] Table 2 Technical Specifications of Static Penetration Tester Load

[0061]

[0062] To ensure the smooth retraction of the static cone penetrometer, this application designs two types of drill rods: blade-type and plow-type. Figure 5 The penetration resistance, side friction resistance, blade (plow) resistance, theoretical penetration torque, pull-out force, and pull-out torque were calculated.

[0063] Referring to the calculation formulas for the penetration resistance and rotational torque of a static cone penetrometer, the mechanical parameters such as the penetration resistance and penetration torque of the blade-type penetrometer can be calculated. The structural dimensions of the blade-type penetrometer are shown in [reference needed]. Figure 5 The calculation results were compared with those of the plow-harrow method, as shown in Table 3.

[0064] Table 3. Penetration and pull-out data of blade-type and plowshare-type drill pipes

[0065]

[0066] As shown in Table 3, a comprehensive comparison reveals that the plow-and-rake design, while meeting the detection function requirements, offers lower torque requirements and superior pull-out resistance, demonstrating significant advantages in motor power consumption and reliability. Therefore, the plow-and-rake design is selected as the preferred option. The blade-type design can be considered as an alternative.

[0067] The payload in this invention can be installed either outside or inside the lunar rover. External installation saves interior space, but the impact of extreme temperature environments must be considered; internal installation provides better temperature control, but occupies limited interior space. The specific installation method can be flexibly selected according to the actual design of the lunar rover and mission requirements.

[0068] In summary, this invention relates to an in-situ static penetrometer method for lunar soil probing on a lunar rover. It proposes an in-situ mechanical exploration technology that allows direct rover mounting without the need for ground anchors, achieving precise measurement of lunar soil mechanical parameters through a combined penetration and shearing working mode. This includes the integrated design of the probe and drill rod, the collaborative working mechanism of the fixed lead screw and rotating inner tube, the use of a sliding pin-groove combination to achieve dual rotation and penetration motion, and the optimized design of the plow-type probe, achieving miniaturization, lightweighting, and high reliability. Through comparative analysis and mechanical calculations of blade-type and plow-type probe schemes, the plow-type scheme, with lower penetration torque and smaller pull-out torque, is selected to ensure low energy consumption and high reliability of the system.

[0069] It should be noted that, in this document, the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such a process, method, article, or apparatus. Unless otherwise specified, an element defined by the phrase "comprising one..." does not exclude the presence of other identical elements in the process, method, article, or apparatus that includes that element.

[0070] The above are merely preferred embodiments of the present invention and do not limit the scope of the patent. Any equivalent structural or procedural transformations made based on the description and drawings of the present invention, or direct or indirect applications in other related technical fields, are similarly included within the scope of patent protection of the present invention.

Claims

1. A method for in-situ static mechanical penetration testing of lunar soil carried by a lunar rover, characterized in that, The lunar regolith in-situ mechanical static cone penetration test (RCP) system and computer equipment were used for the test. The RCP system comprises four parts: a penetrometer, a drilling subsystem, a data acquisition subsystem, and an electrical control and management subsystem. The penetrometer is used to acquire the penetration resistance during drilling; the drilling subsystem provides drilling power and rotational torque; the data acquisition subsystem mainly records the current and speed data of the motor, and acquires penetration resistance, acceleration, and attitude data; the electrical control and management subsystem supports the transmission and reception of lunar surface payload commands and controls the exploration mission. The method includes the following steps: The drilling subsystem is used to obtain drilling power and rotational torque, the mechanical sensors of the static cone penetrometer are used to obtain resistance characteristics data of lunar soil, and the rotational torque generated by the rotational shearing of lunar soil by the drilling subsystem is used. Using data obtained from a lunar regolith in-situ mechanical static cone penetration test system based on computer equipment, a mechanical equation F=f1(c, φ) was constructed to represent the penetration resistance F and the lunar regolith cohesion c and internal friction angle φ. Similarly, a mechanical equation M=f2(c, φ) was constructed to represent the rotational torque M and the lunar regolith cohesion c and internal friction angle φ. These equations were used to interpret the in-situ mechanical properties of the lunar regolith, where the in-situ mechanical properties include at least the lunar regolith cohesion c and the internal friction angle φ. Specifically, the mechanical equation F=f1(c, φ) is constructed using data obtained from a lunar regolith in-situ mechanical static penetration test system based on computer equipment, relating the penetration resistance F, lunar regolith cohesion c, and internal friction angle φ. Calculate penetration resistance: Calculate the initial geostress distribution of lunar soil: ； in, For penetration resistance, It is the geostress related to the penetration depth, where A is the area of ​​the static cone penetrometer. It is the internal friction angle; Calculate the vertical stress of lunar soil: ； in, Let z be the density of lunar soil and z be the penetration depth. This refers to the gravitational acceleration on the lunar surface. Calculate sidewall resistance: ； ； in, For sidewall resistance, and It is a constant; Calculate the penetration resistance of the static cone penetrometer: ； The parameters are: penetration depth z = 500 mm, h is the drill pipe depth, and g... M = 1.62 m / s2, drill rod diameter d = 26 mm, plow diameter D = 46 mm, cone angle of the penetrometer probe θ = 30°, friction coefficient μ0 = 0.6, constant K0 = 0.5, internal friction angle φ = 43°; The mechanical equation M=f2(c,φ) relating the rotational torque M to the lunar regolith cohesion c and internal friction angle φ includes calculating the required rotational torque T when the penetration depth z is 50 cm. ； Where F is the total penetration resistance of the static penetrometer; d1 = 2.6 cm is the diameter of the penetrometer; A1 is the shear area; and D1 = 5 cm is the shear diameter. The internal friction angle of the lunar soil is taken as 43°. To bear the pressure on the blades at the tip of the drill pipe. Vertical stress of lunar soil : , in, Given the gravitational acceleration on the lunar surface, the theoretical torque is approximately 1.89 N·m; This also includes: the calculation process for the pull-out moment M of the drill pipe involves substituting the pull-out force R into the formula. Thus, the pull-out torque M is obtained.

2. The method for in-situ static mechanical penetration testing of lunar soil carried by a lunar rover according to claim 1, characterized in that, The penetration tester includes a probe and a mechanical sensor; the drilling subsystem includes a fixed lead screw, a drill rod, a rotating inner tube, a motor, and a protective housing. The top of the drill rod is equipped with a sliding pin that engages with the fixed lead screw. The rotating inner tube is driven by a gear driven by the motor, which in turn drives the rotating inner tube to rotate, thereby rotating the drill rod. The fixed lead screw is fixed to the top of the outer protective housing and engages with the central threaded hole at the top of the drill rod. The rotation of the drill rod is coordinated with the fixed lead screw nut to cause the drill rod to shift along the lead screw axis.

3. The in-situ mechanical static cone penetration test method for lunar soil carried by a lunar rover according to claim 2, characterized in that, After interpreting the in-situ mechanical property parameters of lunar soil, the method further includes: based on the interpreted in-situ mechanical property parameters of lunar soil, using the Bekker bearing model to construct mathematical expressions for the mechanical property parameters and bearing capacity of lunar soil, and using the Janosi shear model to construct the correlation between the in-situ mechanical property parameters and the shear strength of lunar soil, so as to construct the bearing and shear models of lunar soil.

4. The in-situ mechanical static cone penetration test method for lunar soil carried by a lunar rover according to claim 2, characterized in that, The process involves using the drilling subsystem to obtain drilling power and rotational torque, using the mechanical sensors of the static penetrometer to acquire resistance characteristic data of the lunar soil, and using the rotational torque generated by the rotational shearing of the lunar soil by the drilling subsystem. This includes: after the lunar rover reaches the designated location, the electrical control management subsystem of the static penetrometer issues a working command to start the motor and propel the penetrometer. The static penetrometer probe, along with the drill rod, penetrates the lunar soil at a speed of 2 cm / min to reach the required drilling depth. Simultaneously, the data acquisition system collects the probe's penetration resistance data, attitude data, and acceleration data, and records the drill rod's rotational speed and the motor's power, providing feedback to control the motor. After the drilling task is completed, the electrical control management subsystem issues a motor reversal command, and the motor control system reverses the motor's rotation to retract the drill rod, terminating the detection at that point. The lunar rover then proceeds to the next detection point.

5. The in-situ mechanical static cone penetration test method for lunar soil carried by a lunar rover according to claim 1, characterized in that, The static cone penetrometer is equipped with two types of drill rods: blade type and plow type. The penetration resistance, sidewall resistance, rotational torque, and pull-out torque are calculated for the blade type static cone penetrometer and the plow type static cone penetrometer, respectively.

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