Journal of Terramechanics最新文献_第3页

Effect of rubber-tracked chassis roller on soil surface vertical stress distribution based on finite element method 基于有限元法的橡胶履带底盘滚轮对土壤表面垂直应力分布的影响

IF 2.4 3区工程技术 Q3 ENGINEERING, ENVIRONMENTAL

Journal of Terramechanics

Pub Date : 2025-07-15 DOI: 10.1016/j.jterra.2025.101080

Zhuohuai Guan , Haitong Li , Tao Jiang , Licheng Xing , Min Zhang , Dong Jiang , Mei Jin

Due to the flexible characteristics of the rubber track, the ground pressure distribution on the soil is uneven, which will greatly increase the risk of soil compaction. Roller in the tracked chassis is a key influencing factor. Therefore, accurate analysis of the effect of the rollers on soil surface vertical stress distribution is important. In this research, the simulation of soil surface vertical stress distribution under rubber track with different roller structures and arrangements was carried out and experimentally validated. Firstly, a load transfer model of the roller-rubber track-soil system was developed. Then, a FEM simulation model of the roller −rubber track-soil system was constructed. The effect a single roller structure and the arrangement of multiple rollers was analyzed. Finally, field tests were carried out to test the soil surface vertical stress distribution with rollers of uniform distribution and dense at both sides. Results showed that the stress peaks were 69.3 kPa and 62.4 kPa, respectively. The soil surface vertical stress under the roller-track contact location was more than twice the average over the whole track surface. The diameter of a single roller and the arrangement of multiple rollers were the most important factors on the stress distribution.

由于橡胶履带的柔性特性，地面压力在土壤上的分布不均匀，会大大增加土壤压实的风险。滚轮在履带式底盘中是一个关键的影响因素。因此，准确分析滚轮对土体表面竖向应力分布的影响具有重要意义。在本研究中，模拟了不同滚轮结构和布置的橡胶履带下的土壤表面垂直应力分布，并进行了实验验证。首先，建立了滚轮-橡胶履带-土体系统的荷载传递模型。然后，建立了滚轮-橡胶履带-土体系统的有限元仿真模型。分析了单辊结构和多辊布置的影响。最后，采用均匀分布、两侧密实的滚轮进行现场试验，测试土体表面竖向应力分布。结果表明，应力峰值分别为69.3 kPa和62.4 kPa。滚轮轨道接触位置下的土壤表面垂直应力是整个轨道表面平均值的2倍以上。单辊直径和多辊布置是影响应力分布的最重要因素。

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引用次数: 0

Bionic design of a anti-sinking walking wheel for micro tillers and wheel-soil interaction model 微型分蘖防下沉行走轮仿生设计及轮-土相互作用模型

IF 2.4 3区工程技术 Q3 ENGINEERING, ENVIRONMENTAL

Journal of Terramechanics

Pub Date : 2025-07-09 DOI: 10.1016/j.jterra.2025.101078

Dianlei Han , Jinrui Hu , Hairui Liu , Lizhi Ren , Qizhi Yang , Bingbo Cui

The existing wheels exhibit suboptimal performance when traversing the paddy fields. This study aims to develop a wheel suitable for the paddy fields. Firstly, an analysis was conducted into the morphological alterations and patterns of the webbed foot, leveraging the kinematic characteristics of mallards. Secondly, a walking wheel featuring anti-sinking and high-traction attributes was conceptualized and designed. Concurrently, a model elucidating the relationship between the contact area and the leg-foot angle variation was formulated. Subsequently, a series of field trials about the walking wheel and the paddy wheel were measured. Within the range of the slip ratio from 0 to 0.47, the drawbar pull, driving torque and sinkage of the walking wheel gradually increase, and the traction efficiency initially ascended and subsequently tapered off. In the paddy field and wetland, in comparison to the paddy wheel, the drawbar pull was augmented by 97.29 % and 51.65 % respectively. These findings validate the superior traction and traversal capabilities of the walking wheel. Finally, a terramechanics model delineating the relationship between the drawbar pull and slip ratio variation was established. This model holds the potential to furnish theoretical and technical underpinnings for augmenting the traction performance of walking wheels.

现有的车轮在穿越稻田时表现出不理想的性能。本研究的目的是研制一种适合水田使用的水轮。首先，利用野鸭的运动特征，分析了蹼足的形态变化和模式。其次，提出并设计了一种具有抗下沉和高牵引特性的步行轮。同时，建立了接触面积与腿脚角度变化关系的模型。随后，对行走轮和稻田轮进行了一系列的田间试验。在滑移比为0 ~ 0.47的范围内，行走轮的拖杆拉力、驱动转矩和下沉逐渐增大，牵引效率先上升后逐渐减小。在水田和湿地中，与水田轮相比，牵引杆拉力分别提高了97.29%和51.65%。这些发现证实了行走轮优越的牵引和穿越能力。最后，建立了拉杆拉力与滑移率变化关系的地质力学模型。该模型有可能为增强步行轮的牵引性能提供理论和技术基础。

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引用次数: 0

DEM-based analysis and optimization of an excavation bucket drum for in-situ resource utilization 基于dem的挖掘斗鼓就地资源利用分析与优化

IF 2.4 3区工程技术 Q3 ENGINEERING, ENVIRONMENTAL

Journal of Terramechanics

Pub Date : 2025-07-08 DOI: 10.1016/j.jterra.2025.101073

Tomoyasu Nakano , Takuya Omura , Rocco Galati , Genya Ishigami

The bucket drum, a cylindrical rotating mechanism that efficiently excavates and collects lunar regolith, is essential for in-situ resource utilization (ISRU). While bucket drums offer advantages in energy efficiency and adaptability to low-gravity conditions, optimizing their shape and motion remains an open issue. Therefore, this paper aims to find an optimal design of the bucket drum using the discrete element method (DEM). We focus on five key design parameters were analyzed: two related to bucket shape (scoop throat length and scoop inlet number) and three related to motion (bucket vertical force, horizontal velocity, and angular velocity). These parameters were evaluated based on two performance indices: sand fill ratio and excavation power consumption. By solving the multi-objective problem of maximizing fill ratio while minimizing power consumption, an optimal design of the bucket drum was identified. Subsequently, a bucket drum with the optimal shape was 3D-printed, and the optimal motion of the bucket drum was applied using the soil excavation test apparatus. The test results qualitatively matched the results derived from the DEM analysis. This highlights the validity of the relationship between the design parameters and two performance indices, contributing to the advancement of ISRU excavation technologies.

桶形滚筒是高效挖掘和收集月球风化层的圆柱形旋转机构，是原位资源利用（ISRU）的重要组成部分。虽然斗式鼓在节能和适应低重力条件方面具有优势，但优化其形状和运动仍然是一个悬而未决的问题。因此，本文旨在利用离散元法（DEM）寻找铲斗滚筒的优化设计方法。我们重点分析了五个关键设计参数：两个与铲斗形状有关（铲斗喉部长度和铲斗入口数量），三个与运动有关（铲斗垂直力、水平速度和角速度）。根据填砂比和开挖能耗两个性能指标对这些参数进行了评价。通过求解最大填充率和最小功耗的多目标问题，确定了铲斗滚筒的优化设计方案。随后，3d打印出最优形状的斗鼓，并在土掘试验装置上应用最优斗鼓运动。测试结果与DEM分析结果定性匹配。这突出了设计参数与两个性能指标之间关系的有效性，有助于ISRU挖掘技术的进步。

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引用次数: 0

UAV-based three-dimensional rough terrain modelling 基于无人机的三维粗糙地形建模

IF 2.4 3区工程技术 Q3 ENGINEERING, ENVIRONMENTAL

Journal of Terramechanics

Pub Date : 2025-07-04 DOI: 10.1016/j.jterra.2025.101079

Herman A. Hamersma, J. Christian van Aswegen, A. Glenn Guthrie, Carl M. Becker, P.Schalk Els

Accurate modelling of the interaction between a tyre and the terrain is crucial for successful vehicle dynamics simulation, particularly in challenging off-road conditions. This study introduces a novel approach for obtaining accurate 3D terrain models for vehicle simulation. An unmanned aerial vehicle (UAV) was used to develop three-dimensional terrain models of a various test tracks. These models were compared with measurements obtained from a traditional road profilometer. Excellent correlation between the two measurement approaches is found. The advantages of the UAV method lie in its speed without compromising accuracy and that measurements are immune to the terrain roughness. In contrast to the labour-intensive measurements required by a mechanical road profilometer and subsequent post-processing, the UAV approach requires minimal time and effort. The UAV method is not coupled to the terrain roughness, thus eliminating the drift associated with other ground-based approaches. The UAV method is insensitive to terrain deformation. This opens the door to modelling very rough and even deformable terrains and using these models for vehicle dynamics simulations in extreme off-road environments. Data analysis is prone to many potential pitfalls which can result in highly inaccurate results that are difficult to detect unless a reliable baseline is available for comparison.

轮胎和地形之间相互作用的精确建模对于成功的车辆动力学模拟至关重要，特别是在具有挑战性的越野条件下。本研究提出了一种新的方法来获得精确的三维地形模型用于车辆仿真。利用一架无人驾驶飞行器（UAV）建立了各种试验轨道的三维地形模型。这些模型与传统道路轮廓仪的测量结果进行了比较。发现两种测量方法之间具有良好的相关性。无人机方法的优点在于其速度而不影响精度，并且测量不受地形粗糙度的影响。与机械道路轮廓仪和随后的后处理所需的劳动密集型测量相比，无人机方法需要最小的时间和努力。无人机方法不受地形粗糙度的影响，从而消除了与其他地面方法相关的漂移。无人机方法对地形变形不敏感。这打开了大门，建模非常粗糙，甚至可变形的地形，并使用这些模型的车辆动力学模拟在极端的越野环境。数据分析容易出现许多潜在的缺陷，这些缺陷可能导致高度不准确的结果，除非有可靠的基线可供比较，否则很难发现这些结果。

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引用次数: 0

Mesomechanical analyses on the failure mechanism of the snow cluster assembly under direct shear test using discrete element method 用离散元法对雪簇组合体直剪破坏机理进行细观力学分析

IF 2.4 3区工程技术 Q3 ENGINEERING, ENVIRONMENTAL

Journal of Terramechanics

Pub Date : 2025-06-23 DOI: 10.1016/j.jterra.2025.101075

Haifeng Huo , Hui Xu , Enzhao Xiao , Tao Li , Xuan Dai , Rundong Li , Bo Zhang , Biao Hu

The shear strength of snow is an important parameter for assessing the safety of polar snow projects. To investigate the bearing and failure mechanisms of compacted snow during shear, a series of direct shear tests and corresponding discrete element simulations were conducted. The discrete element model was established using the “falling snow method” to simulate snowflake generation, landing, compression, and sintering. The contact model parameters were determined based on tested data, and simulated strengths under direct shear matched the experimental results. Results indicate that snow with a density below 450 kg·m⁻³ primarily fails through bending, while those at or above this density mainly fail by shearing. As density and normal stress increase and sintering decreases, the percentage of bond shear failures increases, while bond bending failures decrease. The contribution of bond contact force to shear stress was greater than that of frictional contact force, with normal contact force contributing more than tangential contact force. At shear’s end, the bond contact force contribution in high-density snow was 66.9 %, lower than the 85.3 % in low-density snow. Additionally, tensile zone breakage consistently exceeded that in the compressive zone.

雪的抗剪强度是评价极地造雪工程安全性的重要参数。为研究压实雪在剪切过程中的承载和破坏机制，进行了一系列直剪试验和离散元模拟。采用“落雪法”建立离散元模型，模拟雪花的产生、降落、压缩和烧结过程。根据试验数据确定了接触模型参数，模拟的直剪强度与试验结果吻合。结果表明，密度在450 kg·m−3以下的雪主要通过弯曲破坏，而密度在450 kg·m−3以上的雪主要通过剪切破坏。随着密度和法向应力的增大，烧结程度的降低，粘结体剪切破坏的比例增加，而粘结体弯曲破坏的比例减少。粘结接触力对剪切应力的贡献大于摩擦接触力，法向接触力的贡献大于切向接触力。在剪切端，高密度雪的粘结接触力贡献为66.9%，低于低密度雪的85.3%。此外，拉伸区破坏始终大于压缩区破坏。

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引用次数: 0

Mechanical properties of loose soil during dynamic penetration of landing pad under microgravity 微重力作用下松散土动力侵彻起落架的力学特性

IF 2.4 3区工程技术 Q3 ENGINEERING, ENVIRONMENTAL

Journal of Terramechanics

Pub Date : 2025-06-17 DOI: 10.1016/j.jterra.2025.101072

Masatsugu Otsuki , Takao Maeda , Shingo Ozaki , Genya Ishigami , Taizo Kobayashi

The safety of lunar and planetary exploration is contingent upon a preliminary assessment of the interaction between loose soils composed of regolith that covers a celestial surface and the landing gear of spacecraft, which should be designed in accordance with the findings of the assessment. However, given the issues associated with replicating the surface layer of celestial bodies on Earth, the verification of the gear design can be challenging. Conducting a real-size low-gravity test in the design verification process of a large spacecraft remains cumbersome and resource intensive. As such, drawing valuable knowledge from scale model tests is the only available solution. This paper presents the results and findings of a dynamic penetration test conducted on a scaled landing pad under microgravity using a drop tower. The experimental findings demonstrate that the results of the dynamic penetration of the pad into the regolith simulant are not necessarily indicative of the worst-case scenario of low-gravity conditions and that they are equivalent to the results obtained in the gravitational environment of the earth. This finding suggests that design verification may be feasible through tests using a full-scale spacecraft model.

月球和行星探测的安全性取决于对覆盖天体表面的由风化层组成的松散土壤与航天器起落架之间相互作用的初步评估，应根据评估结果设计起落架。然而，考虑到与复制地球上天体表层相关的问题，齿轮设计的验证可能具有挑战性。在大型航天器的设计验证过程中，进行实际尺寸的低重力试验仍然是繁琐且资源密集的。因此，从比例模型测试中获取有价值的知识是唯一可行的解决方案。本文介绍了在微重力条件下，利用落塔在一个有比例的着陆平台上进行的动态侵彻试验的结果和发现。实验结果表明，模拟平台动态侵彻风化层的结果并不一定代表低重力条件下的最坏情况，而是与地球重力环境下的结果相当。这一发现表明，通过使用全尺寸航天器模型进行测试，设计验证可能是可行的。

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引用次数: 0

Heavy-load variable stiffness lunar wheel based on adjustable tensegrity unit 基于可调张拉整体单元的重载变刚度月轮

IF 2.4 3区工程技术 Q3 ENGINEERING, ENVIRONMENTAL

Journal of Terramechanics

Pub Date : 2025-06-11 DOI: 10.1016/j.jterra.2025.101074

Shengpu Zhao, Xiaotian Zhang, Zelin Zhang, Lei Bao, Qingcheng Guo

Manned lunar landings have been prioritized as interstellar exploration capabilities continue to improve. Among them, the heavy-duty manned lunar rover is an essential tool for human lunar exploration. However, the lunar surface presents a highly complex and dynamic environment, rendering traditional lunar wheels inadequate for simultaneously addressing multifaceted requirements such as landing, locomotion, and vibration isolation. A heavy-load variable stiffness lunar wheel based on adjustable tensegrity unit is proposed, offering three stiffness states with a range of up to 178.25%. First, the wheel’s variable stiffness mechanism and corresponding applicable scenarios are introduced, along with the theoretical solution for vertical stiffness. Next, the static simulation using the finite element method (FEM) is performed to validate the theoretical solution. The lateral stiffness, impact tolerance, and single-point deformation capacity of the wheel are investigated. Results indicate that the current wheel addresses the limitations of traditional flexible lunar wheels with low lateral stiffness. Meanwhile, the wheel’s impact tolerance and single-point deformation capacity effectively meet the needs of rovers landing and operating on rugged terrains. Finally, a reduced-size prototype of the wheel is fabricated based on 3D printing technology, and the effectiveness of the variable stiffness mechanism is experimentally demonstrated.

随着星际探测能力的不断提高，载人登月已成为优先事项。其中，重型载人月球车是人类探月必不可少的工具。然而，月球表面呈现出高度复杂和动态的环境，使得传统的月球轮无法同时满足着陆、运动和隔振等多方面的要求。提出了一种基于可调张拉整体单元的重载变刚度月轮，提供了三种刚度状态，最大刚度范围为178.25%。首先，介绍了车轮变刚度机理及其应用场景，并给出了车轮垂直刚度的理论解。其次，利用有限元法进行了静力仿真，验证了理论解的正确性。研究了车轮的横向刚度、冲击公差和单点变形能力。结果表明，该车轮解决了传统柔性月球车轮侧向刚度低的局限性。同时，车轮的冲击容忍度和单点变形能力有效地满足了探测车在崎岖地形上着陆和运行的需要。最后，利用3D打印技术制作了缩小尺寸的车轮原型，并对变刚度机构的有效性进行了实验验证。

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引用次数: 0

In-house instrument development and updated classical equations for compacted snow characterization 内部仪器的发展和更新的经典方程压实雪表征

IF 2.4 3区工程技术 Q3 ENGINEERING, ENVIRONMENTAL

Journal of Terramechanics

Pub Date : 2025-05-22 DOI: 10.1016/j.jterra.2025.101069

Mohit Nitin Shenvi , Corina Sandu , Costin Untaroiu

Testing and evaluation of commercial passenger car and truck tires for severe snow usage are performed on compacted snow tracks based on the ASTM F1805-20 standard. The snow track is characterized for these tests using the CTI penetrometer. Evaluating the compactness of the snow track as an index number is helpful, but it does not provide information that can be useful from a simulation/modeling perspective.

In this work, a new device was developed that was inspired by the ‘Russian snow penetrometer’ to help evaluate the compressive and shear properties of snow. It was found that the classical methods of analysis used for Rammsonde penetrometers and Clegg hammers had some discrepancies that partially stem from assumptions made in their formulations. This work proposes modifications to the equations thereby improving their outputs to align with a more physics-oriented approach. The assumptions in the formation of classical equations are not incorrect but may not be completely accurate for cones with a higher surface area to base area ratio.

Future work could be assessing the accuracy of the devised equations in different terrain conditions and a sensitivity study to identify critical cone angles in different conditions.

根据ASTM F1805-20标准，商用乘用车和卡车轮胎在压实的雪地轨道上进行了严重积雪使用的测试和评估。在这些测试中使用CTI穿透计表征雪迹。将雪道的密实度作为索引值进行评估是有帮助的，但它不能提供从模拟/建模角度来看有用的信息。在这项工作中，受“俄罗斯雪穿透仪”的启发，开发了一种新设备，以帮助评估雪的压缩和剪切特性。人们发现，用于雷蒙德穿透仪和克莱格锤的经典分析方法存在一些差异，部分原因在于它们的公式中所做的假设。这项工作提出了对方程的修改，从而改善了它们的输出，使其与更面向物理的方法保持一致。经典方程形成中的假设并非不正确，但对于具有较高表面积与基面积比的锥体可能不完全准确。未来的工作可能是评估设计方程在不同地形条件下的准确性，以及在不同条件下识别临界锥角的敏感性研究。

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引用次数: 0

Extending granular resistive force theory to cohesive powder-scale media 将颗粒阻力理论推广到粘性粉状介质

IF 2.4 3区工程技术 Q3 ENGINEERING, ENVIRONMENTAL

Journal of Terramechanics

Pub Date : 2025-05-20 DOI: 10.1016/j.jterra.2025.101058

Deniz Kerimoglu , Eloïse Marteau , Daniel Soto , Daniel I. Goldman

Intrusions into granular media are common in natural and engineered settings (e.g. during animal locomotion and planetary landings). While intrusion of complex shapes in dry non-cohesive granular materials is well studied, less is known about intrusion in cohesive powders. Granular resistive force theory (RFT) — a reduced-order frictional fluid model — quantitatively predicts intrusion forces in dry, non-cohesive granular media by assuming a linear superposition of angularly dependent elemental stresses acting on arbitrarily shaped intruders. Here we extend RFT’s applicability to cohesive dry powders, enabling quantitative modeling of forces on complex shapes during intrusion. To do so, we first conduct intrusion experiments into dry cornstarch powder to create stress functions. These stresses are similar to non-cohesive media; however, we observe relatively higher resistance to horizontal intrusions in cohesive powder compared to non-cohesive media. We use the model to identify geometries that enhance resistance to intrusion in cohesive powder, aiming to minimize sinkage. Our calculations, supported by experimental verification, suggest that a flat surface generates the largest stress across various intrusion angles while a curved surface exhibits the largest resistive force to vertical intrusion. Our model can thus facilitate optimizing design and movement strategies for robotic platforms (e.g. extraterrestrial landers) operating in such environments.

侵入颗粒介质在自然和工程环境中很常见（例如在动物运动和行星着陆期间）。虽然在干燥的非粘性颗粒材料中复杂形状的侵入已经得到了很好的研究，但对粘性粉末中的侵入知之甚少。颗粒阻力理论（RFT）是一种降阶摩擦流体模型，通过假设作用在任意形状的侵入物上的角相关元素应力的线性叠加，定量预测干燥、非粘性颗粒介质中的侵入力。在这里，我们将RFT的适用性扩展到粘性干粉，使在入侵过程中对复杂形状的力进行定量建模。为此，我们首先对干燥的玉米淀粉粉进行入侵实验，以产生应力函数。这些应力与非粘性介质相似；然而，我们观察到与非粘性介质相比，粘性粉末对水平侵入的抵抗力相对较高。我们使用该模型来识别几何形状，增强抵抗侵入的粘性粉末，旨在最大限度地减少下沉。我们的计算得到了实验验证的支持，表明平面在各种入侵角度上产生的应力最大，而曲面对垂直入侵的阻力最大。因此，我们的模型可以促进在这种环境下运行的机器人平台（例如地外着陆器）的优化设计和运动策略。

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引用次数: 0

Development and evaluation of high-speed single-wheel test for lunar exploration rover

IF 2.4 3区工程技术 Q3 ENGINEERING, ENVIRONMENTAL

Journal of Terramechanics

Pub Date : 2025-05-13 DOI: 10.1016/j.jterra.2025.101057

Keisuke Takehana , Kento Funabiki , Kosuke Okuni , Tsutomu Hamabe , Kenji Niwa , Katsuaki Tanaka , Kazuya Yoshida

Rovers have significantly contributed to lunar exploration in recent years; however, most of them operate at low speeds, resulting in prolonged exploration times. For future space exploration, it is crucial to develop rovers capable of high-speed traversal and to gain a deeper understanding of the interaction between wheels and soil. We have developed a single-wheel testbed capable of operating at a speed of 5 m/s, which is substantially higher than the conventional unmanned rover’s typical speed of approximately 0.01 m/s. This apparatus allows for precise control of the wheel’s rotational and translational speeds and can actively manage the vertical load on the wheel. In this paper, we present controlled slip ratio experiments using this high-speed testbed. We measure the forces acting on the wheel, the sinkage, and evaluate the wheel’s performance in terms of its tractive capabilities. The experimental results indicate that the tractive performance decreases with an increase in the load on the wheel. Moreover, we discover that performance also declines as speed increases. This study provides valuable insights into the mechanisms of wheel performance during high-speed traversal, which will be beneficial for the development of future high-speed exploration rovers.

近年来，月球车对月球探测做出了重大贡献；然而，它们大多以低速运行，导致勘探时间延长。对于未来的太空探索，至关重要的是开发能够高速穿越的探测车，并对车轮和土壤之间的相互作用有更深入的了解。我们已经开发了一个单轮试验台，能够以5米/秒的速度运行，这大大高于传统无人探测器的典型速度，大约为0.01米/秒。该装置可以精确控制车轮的旋转和平移速度，并可以主动管理车轮上的垂直负载。本文利用该高速试验台进行了控制滑移比实验。我们测量作用在车轮上的力，下沉，并根据其牵引能力评估车轮的性能。实验结果表明，随着车轮载荷的增大，车轮的牵引性能下降。此外，我们发现性能也随着速度的增加而下降。该研究为高速穿越时车轮性能的机理提供了有价值的见解，这将有利于未来高速探测车的发展。

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引用次数: 0