Journal of Terramechanics最新文献

英文中文

Effect of vertical load on track traction under different soil moisture content 不同土壤含水量下垂直荷载对轨道牵引力的影响

IF 2.4 3区工程技术 Q3 ENGINEERING, ENVIRONMENTAL

Journal of Terramechanics

Pub Date : 2024-12-20 DOI: 10.1016/j.jterra.2024.101044

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

Comprehensive analysis of the tractive performance is central to the design of tracked agriculture vehicles, particularly in challenging terrain conditions. To assess the effect of altering the track traction, the stress state of the track plate and grousers were analyzed based on the terramechanics. A simulation model based on the discrete element method (DEM) was proposed to explore the displacement of soil particles and stress distribution within the soil. Subsequently, a test bench was developed to investigate the effect of vertical load, soil moisture content, and grouser height on the maximum track traction. The results demonstrated that DEM simulation could reproduce the experimental results sufficiently well with a relative error of 3.5 % for maximum traction. The highest vertical stress is located beneath the grousers and the horizontal stresses are found to be higher near the bottom of the grousers. The vertical load exerts the most significant influence on track traction. Moisture content mainly affects the rate of increase in track traction at different vertical loads. At the moisture contents of 10 % and 15 %, and under vertical loads of 1000 N and 1500 N, the grouser height had little impact on maximum traction. However, at a soil moisture content of 25 % and under vertical loads of 2500 N and 3000 N, increasing the grouser height resulted in a notable enhancement of track traction.

对牵引性能的综合分析是履带式农业车辆设计的核心，特别是在具有挑战性的地形条件下。为了评估改变履带牵引力的效果，基于地形力学分析了履带板和履带的受力状态。提出了一种基于离散元法（DEM）的模拟模型来研究土粒的位移和土内应力分布。随后，建立了一个试验平台，研究了垂直荷载、土壤含水量和土鼠高度对最大轨道牵引力的影响。结果表明，DEM模拟可以很好地再现实验结果，最大牵引力的相对误差为3.5%。竖向应力最高的位置在土槽下方，水平应力在土槽底部附近较高。竖向荷载对轨道牵引力的影响最为显著。在不同垂直荷载作用下，含水率主要影响轨道牵引力的增加速率。在含水率为10%和15%，垂直荷载为1000 N和1500 N时，草身高对最大牵引力影响不大。而在土壤含水量为25%时，在2500 N和3000 N的垂直荷载下，增加土鼠高度可显著增强履带牵引力。

{"title":"Effect of vertical load on track traction under different soil moisture content","authors":"Zhuohuai Guan, Dong Jiang, Min Zhang, Mei Jin, Haitong Li, Tao Jiang","doi":"10.1016/j.jterra.2024.101044","DOIUrl":"10.1016/j.jterra.2024.101044","url":null,"abstract":"<div><div>Comprehensive analysis of the tractive performance is central to the design of tracked agriculture vehicles, particularly in challenging terrain conditions. To assess the effect of altering the track traction, the stress state of the track plate and grousers were analyzed based on the terramechanics. A simulation model based on the discrete element method (DEM) was proposed to explore the displacement of soil particles and stress distribution within the soil. Subsequently, a test bench was developed to investigate the effect of vertical load, soil moisture content, and grouser height on the maximum track traction. The results demonstrated that DEM simulation could reproduce the experimental results sufficiently well with a relative error of 3.5 % for maximum traction. The highest vertical stress is located beneath the grousers and the horizontal stresses are found to be higher near the bottom of the grousers. The vertical load exerts the most significant influence on track traction. Moisture content mainly affects the rate of increase in track traction at different vertical loads. At the moisture contents of 10 % and 15 %, and under vertical loads of 1000 N and 1500 N, the grouser height had little impact on maximum traction. However, at a soil moisture content of 25 % and under vertical loads of 2500 N and 3000 N, increasing the grouser height resulted in a notable enhancement of track traction.</div></div>","PeriodicalId":50023,"journal":{"name":"Journal of Terramechanics","volume":"118 ","pages":"Article 101044"},"PeriodicalIF":2.4,"publicationDate":"2024-12-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143148054","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Editorial: Best papers of the ISTVS 2023 conference 编辑：ISTVS 2023会议最佳论文

IF 2.4 3区工程技术 Q3 ENGINEERING, ENVIRONMENTAL

Journal of Terramechanics

Pub Date : 2024-12-13 DOI: 10.1016/j.jterra.2024.101042

Jarosław Pytka, Schalk Els, Massimo Martelli

引用次数: 0

Interaction-aware control for robotic vegetation override in off-road environments 越野环境下机器人植被覆盖的交互感知控制

IF 2.4 3区工程技术 Q3 ENGINEERING, ENVIRONMENTAL

Journal of Terramechanics

Pub Date : 2024-11-29 DOI: 10.1016/j.jterra.2024.101034

Charles Noren, Bhaskar Vundurthy, Sebastian Scherer, Matthew Travers

Robotic systems tasked with completing off-road economic, military, or humanitarian missions often encounter environmental objects when traversing unstructured terrains. Certain objects (e.g. safety cones) must be avoided to ensure operational integrity, but others (e.g. small vegetation) can be interacted with (e.g. overridden/pushed) safely. Pure object-avoidance assumptions in conventional robotic system navigation policies may lead to inefficient (slow) or overly-cautious (immobilized) traversal behaviors in off-road terrains. To address this gap in system performance, we draw inspiration from existing hybrid dynamic system control literature. We have designed a nonlinear trajectory optimization controller that utilizes vegetation-interaction models as a jump map in the dynamics constraint. In contrast to purely vision-based navigation policies which classify the traversability of obstacles, the allowable subset of objects with which the vehicle can safely interact is now characterized by a data-driven collision model and the existence of a dynamically-feasible trajectory which satisfies the contact constraints. The controller’s capabilities are demonstrated on a full-sized autonomous utility task vehicle where objects including posts and trees of up to 25.4 [mm] and 81.8 [mm] diameter are overridden.

完成越野经济、军事或人道主义任务的机器人系统在穿越非结构化地形时经常遇到环境物体。某些物体（如安全锥）必须避免以确保操作完整性，但其他物体（如小植被）可以安全地与之交互（如覆盖/推动）。在传统的机器人系统导航策略中，单纯的物体回避假设可能导致在越野地形中低效（缓慢）或过于谨慎（固定）的穿越行为。为了解决系统性能上的这一差距，我们从现有的混合动态系统控制文献中汲取灵感。我们设计了一个非线性轨迹优化控制器，利用植被相互作用模型作为动力学约束中的跳跃图。与对障碍物可穿越性进行分类的纯粹基于视觉的导航策略相比，车辆可以与之安全交互的允许对象子集现在由数据驱动的碰撞模型和满足接触约束的动态可行轨迹的存在性来表征。该控制器的功能在一辆全尺寸自动多功能任务车上进行了演示，该任务车辆覆盖了直径25.4毫米和81.8毫米的柱子和树木等物体。

{"title":"Interaction-aware control for robotic vegetation override in off-road environments","authors":"Charles Noren, Bhaskar Vundurthy, Sebastian Scherer, Matthew Travers","doi":"10.1016/j.jterra.2024.101034","DOIUrl":"10.1016/j.jterra.2024.101034","url":null,"abstract":"<div><div>Robotic systems tasked with completing off-road economic, military, or humanitarian missions often encounter environmental objects when traversing unstructured terrains. Certain objects (e.g. safety cones) must be avoided to ensure operational integrity, but others (e.g. small vegetation) can be interacted with (e.g. overridden/pushed) safely. Pure object-avoidance assumptions in conventional robotic system navigation policies may lead to inefficient (slow) or overly-cautious (immobilized) traversal behaviors in off-road terrains. To address this gap in system performance, we draw inspiration from existing hybrid dynamic system control literature. We have designed a nonlinear trajectory optimization controller that utilizes vegetation-interaction models as a jump map in the dynamics constraint. In contrast to purely vision-based navigation policies which classify the traversability of obstacles, the allowable subset of objects with which the vehicle can safely interact is now characterized by a data-driven collision model and the existence of a dynamically-feasible trajectory which satisfies the contact constraints. The controller’s capabilities are demonstrated on a full-sized autonomous utility task vehicle where objects including posts and trees of up to 25.4 [mm] and 81.8 [mm] diameter are overridden.</div></div>","PeriodicalId":50023,"journal":{"name":"Journal of Terramechanics","volume":"117 ","pages":"Article 101034"},"PeriodicalIF":2.4,"publicationDate":"2024-11-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142745171","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Analyzing bearing capacity changes due to vibration in discrete element method simulations 用离散元法模拟分析振动引起的承载力变化

IF 2.4 3区工程技术 Q3 ENGINEERING, ENVIRONMENTAL

Journal of Terramechanics

Pub Date : 2024-11-29 DOI: 10.1016/j.jterra.2024.101031

Tomohiro Watanabe , Ryoma Higashiyama , Dai Watanabe , Kojiro Iizuka

Recently, legged robots have gained significant attention as highly mobile platforms for planetary exploration. However, the surfaces of celestial bodies such as the Moon are mainly composed of loose materials, leading to slippage due to the deformation of the surface under the movements of the rover’s legs. To address this issue, we proposed a walking method designed to minimize slippage. Our previous research demonstrated that applying vibrations can increase both the shear strength of the ground and the amount of the rover’s leg subsidence, thereby enhancing the ground’s bearing capacity, which is related to the counterforce provided by the ground against the legs of the rover. For the robot to perform optimally, it is essential to accurately estimate this bearing capacity to select efficient vibration settings. In this study, we utilized the discrete element method (DEM) to simulate the ground’s bearing capacity under various vibrational influences changing both the sinkage depth of a leg and the vibration frequency. Our simulations successfully mirrored the real-world effects of vibrations on bearing capacity, providing insightful perspectives on how vibration can be used to enhance ground support for these robotic explorers.

最近，有腿机器人作为行星探测的高机动性平台受到了极大的关注。然而，月球等天体的表面主要由松散的物质组成，在月球车腿的运动下，表面会发生变形，导致滑动。为了解决这个问题，我们提出了一种旨在最小化滑移的行走方法。我们之前的研究表明，施加振动可以增加地面的抗剪强度和月球车腿下沉的量，从而提高地面的承载能力，这与地面对月球车腿提供的反作用力有关。为了使机器人发挥最佳性能，准确估计其承载能力以选择有效的振动设置至关重要。本研究采用离散元法（DEM）模拟了不同振动影响下的地基承载力，同时改变腿的下沉深度和振动频率。我们的模拟成功地反映了振动对承载能力的现实影响，为如何利用振动来增强这些机器人探险者的地面支持提供了有见地的观点。

{"title":"Analyzing bearing capacity changes due to vibration in discrete element method simulations","authors":"Tomohiro Watanabe , Ryoma Higashiyama , Dai Watanabe , Kojiro Iizuka","doi":"10.1016/j.jterra.2024.101031","DOIUrl":"10.1016/j.jterra.2024.101031","url":null,"abstract":"<div><div>Recently, legged robots have gained significant attention as highly mobile platforms for planetary exploration. However, the surfaces of celestial bodies such as the Moon are mainly composed of loose materials, leading to slippage due to the deformation of the surface under the movements of the rover’s legs. To address this issue, we proposed a walking method designed to minimize slippage. Our previous research demonstrated that applying vibrations can increase both the shear strength of the ground and the amount of the rover’s leg subsidence, thereby enhancing the ground’s bearing capacity, which is related to the counterforce provided by the ground against the legs of the rover. For the robot to perform optimally, it is essential to accurately estimate this bearing capacity to select efficient vibration settings. In this study, we utilized the discrete element method (DEM) to simulate the ground’s bearing capacity under various vibrational influences changing both the sinkage depth of a leg and the vibration frequency. Our simulations successfully mirrored the real-world effects of vibrations on bearing capacity, providing insightful perspectives on how vibration can be used to enhance ground support for these robotic explorers.</div></div>","PeriodicalId":50023,"journal":{"name":"Journal of Terramechanics","volume":"118 ","pages":"Article 101031"},"PeriodicalIF":2.4,"publicationDate":"2024-11-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142744582","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Optimization of subsoiler design using similitude-based DEM simulation and soil bin testing on cohesive-frictional artificial soil 利用基于模拟的 DEM 仿真和粘性摩擦人工土壤的土仓测试优化底土机设计

IF 2.4 3区工程技术 Q3 ENGINEERING, ENVIRONMENTAL

Journal of Terramechanics

Pub Date : 2024-11-22 DOI: 10.1016/j.jterra.2024.101026

Adewale M. Sedara , Mohamed A.A. Abdeldayem , Francisco Pratas Glycerio de Freitas , Tekeste Z. Mehari

The study highlights the need for effective and efficient methods in designing tillage shanks to alleviate deep soil compaction, especially in wet soil conditions. Current techniques relying on full-scale tillage tools testing are prone to costly and time-consuming engineering product development cycles. DEM simulation of soil-to-shank interaction was utilized for screening twelve geometrically scaled (1:5.63) shanks to top-ranked six shanks, aiming reduced soil horizontal forces and maximum bulk density difference. Six scaled shanks (a straight, a bent, and four paraplow shapes) were fabricated and tested using a split-plot design soil bin experiment on cohesive-frictional artificial soil to investigate their performances on soil reaction forces and soil loosening parameters. Shank design had significant effects (p < 0.05) on energy responses (soil horizontal and vertical reaction forces), above-ground soil loosening (cross-sectional area, trench width, bulk density difference), and below-ground soil loosening (soil rupture area, D1 and D2) parameters. Using an optimization profiler, S-3 (β = 60°, α = 45°) demonstrated the best overall desirability score (0.58) with objectives reducing soil reaction forces and maximizing soil loosening. Manufacturing the S-3 to a full scale is proposed for evaluating its efficiency in tillage energy and soil loosening on field soil conditions for subsoil compaction management.

这项研究突出表明，在设计耕地刀柄时需要采用有效和高效的方法来减轻土壤深层压实，尤其是在潮湿的土壤条件下。目前的技术依赖于全尺寸耕具测试，容易造成工程产品开发周期成本高、耗时长。利用 DEM 模拟土壤与刀柄之间的相互作用，筛选出 12 个几何比例（1:5.63）的刀柄，最终确定了排名靠前的 6 个刀柄，目的是减少土壤水平力和最大容重差。我们制作了六种不同形状的刀柄（一种直柄、一种弯柄、四种paraplow形状），并在粘性摩擦人造土壤上进行了分块设计的土壤仓实验，以研究它们在土壤反作用力和土壤疏松参数上的性能。柄部设计对能量响应（土壤水平和垂直反作用力）、地面松土（横截面积、沟宽、容重差）和地下松土（土壤破裂面积、D1 和 D2）参数有显著影响（p < 0.05）。利用优化剖面仪，S-3（β = 60°，α = 45°）显示出最佳的总体可取性得分（0.58），其目标是减少土壤反作用力，最大限度地提高土壤疏松度。建议对 S-3 进行大规模制造，以评估其在田间土壤条件下的耕作能量和松土效率，从而进行底土压实管理。

{"title":"Optimization of subsoiler design using similitude-based DEM simulation and soil bin testing on cohesive-frictional artificial soil","authors":"Adewale M. Sedara , Mohamed A.A. Abdeldayem , Francisco Pratas Glycerio de Freitas , Tekeste Z. Mehari","doi":"10.1016/j.jterra.2024.101026","DOIUrl":"10.1016/j.jterra.2024.101026","url":null,"abstract":"<div><div>The study highlights the need for effective and efficient methods in designing tillage shanks to alleviate deep soil compaction, especially in wet soil conditions. Current techniques relying on full-scale tillage tools testing are prone to costly and time-consuming engineering product development cycles. DEM simulation of soil-to-shank interaction was utilized for screening twelve geometrically scaled (1:5.63) shanks to top-ranked six shanks, aiming reduced soil horizontal forces and maximum bulk density difference. Six scaled shanks (a straight, a bent, and four paraplow shapes) were fabricated and tested using a split-plot design soil bin experiment on cohesive-frictional artificial soil to investigate their performances on soil reaction forces and soil loosening parameters. Shank design had significant effects (<em>p</em> < 0.05) on energy responses (soil horizontal and vertical reaction forces), above-ground soil loosening (cross-sectional area, trench width, bulk density difference), and below-ground soil loosening (soil rupture area, D1 and D2) parameters. Using an optimization profiler, S-3 (β = 60°, α = 45°) demonstrated the best overall desirability score (0.58) with objectives reducing soil reaction forces and maximizing soil loosening. Manufacturing the S-3 to a full scale is proposed for evaluating its efficiency in tillage energy and soil loosening on field soil conditions for subsoil compaction management.</div></div>","PeriodicalId":50023,"journal":{"name":"Journal of Terramechanics","volume":"117 ","pages":"Article 101026"},"PeriodicalIF":2.4,"publicationDate":"2024-11-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142700793","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

A Riemann-based SPH formulation for modelling elastoplastic soil behaviour using a Drucker–Prager model 利用德鲁克-普拉格模型建立弹塑性土壤行为模型的基于黎曼的 SPH 公式

IF 2.4 3区工程技术 Q3 ENGINEERING, ENVIRONMENTAL

Journal of Terramechanics

Pub Date : 2024-11-21 DOI: 10.1016/j.jterra.2024.101033

M. Lallemand , C. De Sousa , C. Hermange , J. Michel , G. Oger

The present paper aims at proposing and investigating a Riemann-based SPH formulation to simulate the elastoplastic behaviour of soils undergoing large deformations, using a Drucker–Prager model. Basing on the pioneer work from Parshikov and Medin (Parshikov and Medin, 2002), a Riemann solver is used to maintain regular fields while being free of tuning parameters. By contrast to the work in Parshikov and Medin (2002) where piecewise constant reconstructions were employed, piecewise linear reconstructions are preferred in this work to reduce the numerical diffusion. A Particle Shifting Technique (PST) is used to maintain regular particle distributions and consequently accurate SPH interpolations. To the best of the author’s knowledge, the use of a Riemann solver specific to solid mechanics with a pressure-dependent elastoplastic Drucker–Prager yield surface to model the behaviour of the material represents a novelty with respect to the existing literature. A Boundary Integral Method (BIM) initially derived for fluid dynamics (Ferrand et al., 2013; Chiron et al., 2019) is adapted to solid mechanics in order to handle complex geometries. It allows to deal with wall treatment without using fictitious particles, and shows satisfactory results even in sharp angle regions. The ability of the proposed Riemann-based formulation to simulate accurately elastoplastic problems and its robustness are examined through several test cases in plane strain conditions. Attention is paid to the capacity of the formulation to mitigate the occurrence of Tensile Instability (TI) with respect to other schemes, for which additional treatment is required to treat this issue, such as the additional artificial stress method (Gray et al., 2001).

本文旨在提出并研究一种基于黎曼的 SPH 公式，利用德鲁克-普拉格模型模拟发生大变形的土壤的弹塑性行为。本文以 Parshikov 和 Medin（Parshikov 和 Medin，2002 年）的开创性工作为基础，使用黎曼求解器来维持规则场，同时不需要调整参数。与 Parshikov 和 Medin（2002 年）采用的片断常数重构不同，本研究优先采用片断线性重构，以减少数值扩散。粒子移动技术（PST）用于保持粒子的规则分布，从而实现精确的 SPH 插值。据作者所知，与现有文献相比，使用固体力学专用的黎曼求解器和与压力相关的弹塑性德鲁克-普拉格屈服面来模拟材料行为是一项创新。边界积分法（BIM）最初用于流体动力学（Ferrand 等人，2013 年；Chiron 等人，2019 年），现适用于固体力学，以处理复杂的几何形状。它可以在不使用虚构粒子的情况下处理壁面，即使在锐角区域也能显示出令人满意的结果。通过几个平面应变条件下的测试案例，考察了所提出的基于黎曼的公式精确模拟弹塑性问题的能力及其稳健性。与其他需要额外处理的方案（如附加人工应力法（Gray 等人，2001 年））相比，该方案能够减轻拉伸不稳定性（TI）的发生。

{"title":"A Riemann-based SPH formulation for modelling elastoplastic soil behaviour using a Drucker–Prager model","authors":"M. Lallemand , C. De Sousa , C. Hermange , J. Michel , G. Oger","doi":"10.1016/j.jterra.2024.101033","DOIUrl":"10.1016/j.jterra.2024.101033","url":null,"abstract":"<div><div>The present paper aims at proposing and investigating a Riemann-based SPH formulation to simulate the elastoplastic behaviour of soils undergoing large deformations, using a Drucker–Prager model. Basing on the pioneer work from Parshikov and Medin (Parshikov and Medin, 2002), a Riemann solver is used to maintain regular fields while being free of tuning parameters. By contrast to the work in Parshikov and Medin (2002) where piecewise constant reconstructions were employed, piecewise linear reconstructions are preferred in this work to reduce the numerical diffusion. A Particle Shifting Technique (PST) is used to maintain regular particle distributions and consequently accurate SPH interpolations. To the best of the author’s knowledge, the use of a Riemann solver specific to solid mechanics with a pressure-dependent elastoplastic Drucker–Prager yield surface to model the behaviour of the material represents a novelty with respect to the existing literature. A Boundary Integral Method (BIM) initially derived for fluid dynamics (Ferrand et al., 2013; Chiron et al., 2019) is adapted to solid mechanics in order to handle complex geometries. It allows to deal with wall treatment without using fictitious particles, and shows satisfactory results even in sharp angle regions. The ability of the proposed Riemann-based formulation to simulate accurately elastoplastic problems and its robustness are examined through several test cases in plane strain conditions. Attention is paid to the capacity of the formulation to mitigate the occurrence of Tensile Instability (TI) with respect to other schemes, for which additional treatment is required to treat this issue, such as the additional artificial stress method (Gray et al., 2001).</div></div>","PeriodicalId":50023,"journal":{"name":"Journal of Terramechanics","volume":"117 ","pages":"Article 101033"},"PeriodicalIF":2.4,"publicationDate":"2024-11-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142700792","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Editorial: Soil modeling and simulation for terramechanics applications of manned and unmanned autonomous vehicles 编辑：载人和无人自动驾驶车辆的地形力学应用土壤建模与模拟

IF 2.4 3区工程技术 Q3 ENGINEERING, ENVIRONMENTAL

Journal of Terramechanics

Pub Date : 2024-11-21 DOI: 10.1016/j.jterra.2024.101032

Mehari Tekeste Guest editor, Thomas R. Way Guest editor, Mustafa Alsaleh Guest editor

引用次数: 0

Acoustic winter terrain classification for offroad autonomous vehicles 用于越野自动驾驶车辆的冬季地形声学分类

IF 2.4 3区工程技术 Q3 ENGINEERING, ENVIRONMENTAL

Journal of Terramechanics

Pub Date : 2024-11-15 DOI: 10.1016/j.jterra.2024.101028

Anthony T. Fragoso

Autonomous vehicles can experience extreme changes in performance when operating over winter surfaces, and require accurate classification to transit them safely. In this work we consider acoustic classification of winter terrain, and demonstrate that a simple and efficient frequency-space analysis exposed to a small convolutional neural network, rather than recurrent architectures or temporally-varying spectrogram inputs, is sufficient to provide near-perfect classification of deep snow, hardpacked surfaces and ice. Using a dual-microphone configuration, we also show that acoustic classification performance is due to a combination of vehicle noises and vehicle-terrain interaction noises, and that engine sounds can serve as a particularly powerful classification cue for offroad environments.

自动驾驶汽车在冬季路面上行驶时，性能会发生剧烈变化，因此需要准确的分类才能安全通过。在这项工作中，我们考虑了冬季地形的声学分类问题，并证明了小型卷积神经网络（而非递归架构或时变频谱图输入）所采用的简单高效的频率空间分析足以对深雪、硬质路面和冰层进行近乎完美的分类。通过使用双麦克风配置，我们还证明了声学分类性能是由车辆噪声和车辆-地形交互噪声共同作用的结果，而且发动机声音可以作为越野环境中特别强大的分类线索。

引用次数: 0

Investigation of steer preview methods to improve predictive control methods on off-road vehicles with realistic actuator delays 研究转向预览方法，以改进具有实际执行器延迟的越野车预测控制方法

IF 2.4 3区工程技术 Q3 ENGINEERING, ENVIRONMENTAL

Journal of Terramechanics

Pub Date : 2024-11-14 DOI: 10.1016/j.jterra.2024.101027

Andries J. Peenze, P. Schalk Els

This paper investigates improvements that can be made to predictive control methods for off-road vehicles by adding of realistic steering preview. The objective of this study is to improve the performance and efficacy of predictive controllers by accounting for significant time delays in active and semi-active systems on vehicles. Traditional zero-order and first-order hold methods for steer preview are compared to a more realistic steer preview method. Semi-active suspension, rear wheel steering, and individual brake actuation are used as the actuators on this off-road vehicle. The results show that the addition of a realistic steering preview improves the handling performance of the vehicle in a severe double lane change manoeuvre on rough roads. Up to 10% reduction in roll angle can be achieved with semi-active suspension control. A 34% reduction in side-slip angle is possible with rear wheel steering control and a 15% reduction in side-slip angle is achieved with differential braking control. The controllers can pre-empt and consider the effect of the actuator time delays, and the preview states from the predictive controller are more representative over the prediction horizon. The findings suggest that the addition of a realistic steering preview can improve the performance of predictive controllers on vehicles. Further investigation of other disturbances and their preview effects on the system should be conducted to find further improvements for predictive control strategies on vehicles.

本文研究了通过添加真实转向预览来改进越野车预测控制方法的可能性。本研究的目的是通过考虑车辆主动和半主动系统中的重大时间延迟，提高预测控制器的性能和功效。将用于转向预览的传统零阶和一阶保持方法与更逼真的转向预览方法进行了比较。半主动悬架、后轮转向和单独的制动装置被用作该越野车的执行器。结果表明，在崎岖路面上进行严重的双车道变道操作时，增加真实的转向预览可提高车辆的操控性能。通过半主动悬架控制，侧倾角最多可减少 10%。通过后轮转向控制可将侧滑角减少 34%，通过差速制动控制可将侧滑角减少 15%。控制器可以预先考虑执行器时间延迟的影响，而且预测控制器的预览状态在预测范围内更具代表性。研究结果表明，增加现实的转向预览可以提高车辆预测控制器的性能。应进一步研究其他干扰及其对系统的预览影响，以进一步改进车辆的预测控制策略。

{"title":"Investigation of steer preview methods to improve predictive control methods on off-road vehicles with realistic actuator delays","authors":"Andries J. Peenze, P. Schalk Els","doi":"10.1016/j.jterra.2024.101027","DOIUrl":"10.1016/j.jterra.2024.101027","url":null,"abstract":"<div><div>This paper investigates improvements that can be made to predictive control methods for off-road vehicles by adding of realistic steering preview. The objective of this study is to improve the performance and efficacy of predictive controllers by accounting for significant time delays in active and semi-active systems on vehicles. Traditional zero-order and first-order hold methods for steer preview are compared to a more realistic steer preview method. Semi-active suspension, rear wheel steering, and individual brake actuation are used as the actuators on this off-road vehicle. The results show that the addition of a realistic steering preview improves the handling performance of the vehicle in a severe double lane change manoeuvre on rough roads. Up to 10% reduction in roll angle can be achieved with semi-active suspension control. A 34% reduction in side-slip angle is possible with rear wheel steering control and a 15% reduction in side-slip angle is achieved with differential braking control. The controllers can pre-empt and consider the effect of the actuator time delays, and the preview states from the predictive controller are more representative over the prediction horizon. The findings suggest that the addition of a realistic steering preview can improve the performance of predictive controllers on vehicles. Further investigation of other disturbances and their preview effects on the system should be conducted to find further improvements for predictive control strategies on vehicles.</div></div>","PeriodicalId":50023,"journal":{"name":"Journal of Terramechanics","volume":"117 ","pages":"Article 101027"},"PeriodicalIF":2.4,"publicationDate":"2024-11-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142650957","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Comparison of selected tire-terrain interaction models from the aspect of accuracy and computational intensity 从精度和计算强度方面比较选定的轮胎-地形相互作用模型

IF 2.4 3区工程技术 Q3 ENGINEERING, ENVIRONMENTAL

Journal of Terramechanics

Pub Date : 2024-11-08 DOI: 10.1016/j.jterra.2024.101030

Dávid Körmöczi , Péter Kiss

Accurate modeling or simulation of the vehicle-terrain interaction is critical for effective off-road vehicle navigation. While several high-accuracy methods exist (for example FEM simulation) they typically require computational capacity that exceeds what can be installed in a vehicle. Therefore, they are not applicable for real-time off-road vehicle navigation purposes, where computer hardware capacity is limited by the need for onboard installation. To address this challenge, simplified and less detailed models must be developed for real-time applications. This paper compares three different two-dimensional static terrain-vehicle models, considering accuracy and computational capacity requirements. Results of the comparison provide insights into the suitability of each model for real-time navigation of off-road vehicles.

车辆与地形相互作用的精确建模或仿真对于有效的越野车导航至关重要。虽然有几种高精度方法（例如有限元模拟），但它们所需的计算能力通常超过车辆所能安装的能力。因此，这些方法不适用于实时越野车辆导航，因为在这种情况下，计算机硬件容量受到车载安装的限制。为了应对这一挑战，必须为实时应用开发简化和不太详细的模型。本文比较了三种不同的二维静态地形-车辆模型，并考虑了精度和计算能力要求。比较结果有助于深入了解每种模型对越野车实时导航的适用性。

引用次数: 0

首页上一页

下一页尾页

类型

全部化学•材料生命科学医学物理工程技术环境•农林材料科学地球科学法学管理学化学环境科学与生态学计算机科学教育学经济学农林科学人文科学生物学数学物理与天体物理心理学综合性期刊其他工业工程理学历史学农学文学信息工程

数据库

全部 ACS Publications Elsevier ieeexplore Springer The Royal Society of Chemistry Wiley

期刊

Journal of Terramechanics

全部 Acc. Chem. Res. ACS Applied Bio Materials ACS Appl. Electron. Mater. ACS Appl. Energy Mater. ACS Appl. Mater. Interfaces ACS Appl. Nano Mater. ACS Appl. Polym. Mater. ACS BIOMATER-SCI ENG ACS Catal. ACS Cent. Sci. ACS Chem. Biol. ACS Chemical Health & Safety ACS Chem. Neurosci. ACS Comb. Sci. ACS Earth Space Chem. ACS Energy Lett. ACS Infect. Dis. ACS Macro Lett. ACS Mater. Lett. ACS Med. Chem. Lett. ACS Nano ACS Omega ACS Photonics ACS Sens. ACS Sustainable Chem. Eng. ACS Synth. Biol. Anal. Chem. BIOCHEMISTRY-US Bioconjugate Chem. BIOMACROMOLECULES Chem. Res. Toxicol. Chem. Rev. Chem. Mater. CRYST GROWTH DES ENERG FUEL Environ. Sci. Technol. Environ. Sci. Technol. Lett. Eur. J. Inorg. Chem. IND ENG CHEM RES Inorg. Chem. J. Agric. Food. Chem. J. Chem. Eng. Data J. Chem. Educ. J. Chem. Inf. Model. J. Chem. Theory Comput. J. Med. Chem. J. Nat. Prod. J PROTEOME RES J. Am. Chem. Soc. LANGMUIR MACROMOLECULES Mol. Pharmaceutics Nano Lett. Org. Lett. ORG PROCESS RES DEV ORGANOMETALLICS J. Org. Chem. J. Phys. Chem. J. Phys. Chem. A J. Phys. Chem. B J. Phys. Chem. C J. Phys. Chem. Lett. Analyst Anal. Methods Biomater. Sci. Catal. Sci. Technol. Chem. Commun. Chem. Soc. Rev. CHEM EDUC RES PRACT CRYSTENGCOMM Dalton Trans. Energy Environ. Sci. ENVIRON SCI-NANO ENVIRON SCI-PROC IMP ENVIRON SCI-WAT RES Faraday Discuss. Food Funct. Green Chem. Inorg. Chem. Front. Integr. Biol. J. Anal. At. Spectrom. J. Mater. Chem. A J. Mater. Chem. B J. Mater. Chem. C Lab Chip Mater. Chem. Front. Mater. Horiz. MEDCHEMCOMM Metallomics Mol. Biosyst. Mol. Syst. Des. Eng. Nanoscale Nanoscale Horiz. Nat. Prod. Rep. New J. Chem. Org. Biomol. Chem. Org. Chem. Front. PHOTOCH PHOTOBIO SCI PCCP Polym. Chem.

﹀