Browse Topic: Terrain

Items (534)
The planning of mountain campus bus routes needs to take into account user demand, convenience, and other factors. This study adopts a comprehensive research method that combines quantitative and qualitative viewpoints. From the perspective of university students, this article studies the demand of campus public transportation and proposes the layout of campus bus routes in mountainous universities to meet the needs of users. The psychological needs questionnaire was used to investigate college students’ expectation of bus station service function. Taking three mountain universities as examples, the integration and selectivity of campus road networks are evaluated by using space syntax analysis, which provides valuable insights into the quality of bus stop areas. This article discusses the correlation between psychological needs assessment of college students and objective conditions of campus road network. The study concludes with the following findings: (1) The pedestrian environment
Duan, RanTang, RuiWang, ZhigangZhao, YixueWang, QidaYang, JiyiSu, Jiafu
Usually hosted in Southern California, the Advanced Clean Transportation (ACT) Expo moved about 265 miles (425 km) north and east for its latest edition, taking place in Las Vegas from May 20-23. Interestingly, that distance challenges the range limits of most Class 8 battery-electric trucks, particularly if traversing hilly terrain or hauling heavy loads. One electric truck capable of covering such a stretch - with its estimated range of up to 500 miles (805 km) fully loaded at 82,000 lb GCW - is the Tesla Semi, which made its trade-show debut at the ACT Expo. “Achieving strong range-to-mass ratios is only possible with a dedicated, purpose-built, ground-up electric platform - exactly what the Semi is. There's no wasted space, the powertrain and the vehicle work hand in hand,” Dan Priestley, senior manager of engineering for the Tesla Semi, said during a keynote in Las Vegas.
Gehm, Ryan
ANYmal has for some time had no problem coping with the stony terrain of Swiss hiking trails. Now researchers at ETH Zurich have taught this quadrupedal robot some new skills: it is proving rather adept at parkour, a sport based on using athletic maneuvers to smoothly negotiate obstacles in an urban environment, which has become very popular. ANYmal is also proficient at dealing with the tricky terrain commonly found on building sites or in disaster areas.
This paper describes an approach to integrating high-fidelity vehicle dynamics with a high-fidelity gaming engine, specifically with respect to terrain. The work is motivated by the experimental need to have both high-fidelity visual content with high-fidelity vehicle dynamics to drive a motion base simulator. To utilize a single source of terrain information, the problem requires the just-in-time sharing of terrain content between the gaming engine and the dynamics model. The solution is implemented as a client-server with the gaming engine acting as a stateless server and the dynamics acting as the client. The client is designed to actively maintain a locally cashed terrain grid around the vehicle and actively refresh it by polling the server in an on-demand mode of operation. The paper discusses the overall architecture, the protocol, the server, and the client designs. A practical implementation is described and shown to effectively function in real-time. The benefit of the server
Brudnak, Mark
Off-roading is the scenario of driving a vehicle on unpaved surfaces such as sand, gravel, riverbeds, rocks, and other natural terrain. Vehicle designed for that purpose requires jumping from height due to uneven surfaces/patches. This also requires them to sustain a high amount of loads acting upon them on impact. Thus, off-roading vehicles should not only provide intended vehicle dynamics performance but at the same time should be durable as well. Drop test which is done in a controlled environment is a widely used method to validate the durability of vehicle in such scenarios wherein the vehicle is dropped from a certain predefined height. In Multibody dynamics simulation, drop test was replicated and acceleration data computed at different locations in the vehicle were correlated with actual physical test data. Correlation was done for different drop heights. This paper presents relevant details of the virtual vehicle modeling, loadcase, test data & subsequent correlation. This
Kaka, VaibhavJain, Arvind
In the last decades, the locomotion of wheeled and tracked vehicles on soft soils has been widely investigated due to the large interest in planetary, agricultural, and military applications. The development of a tire-soft soil contact model which accurately represents the micro and macro-scale interactions plays a crucial role for the performance assessment in off-road conditions since vehicle traction and handling are strongly influenced by the soil characteristics. In this framework, the analysis of realistic operative conditions turns out to be a challenging research target. In this research work, a semi-empirical model describing the interaction between a tire and homogeneous and fine-grained soils is developed in Matlab/Simulink. The stress distribution and the resulting forces at the contact patch are based on well-known terramechanics theories, such as pressure-sinkage Bekker’s approach and Mohr-Coulomb’s failure criterion. The force exerted by the soil on the sidewall of the
Zerbato, LucaVella, Angelo DomenicoGalvagno, EnricoVigliani, AlessandroData, SilvioSacchi, Matteo Eugenio
The soft and rough terrain on the planet's surface significantly affects the ride and safety of rovers during high-speed driving, which imposes high requirements for the control of the suspension system of planet rovers. To ensure good ride comfort of the planet rover during operation in the low-gravity environment of the planet's surface, this study develops an active suspension control strategy for torsion spring and torsional damper suspension systems for planet rovers. Firstly, an equivalent dynamic model of the suspension system is derived. Based on fractal principles, a road model of planetary surface is established. Then, a fuzzy-PID based control strategy aimed at improving ride comfort for the planet rover suspension is established and validated on both flat and rough terrains. This study provides an advanced suspension system control strategy for planet rovers' ride comfort and safety during high-speed driving, ensuring the smooth operation of vehicles on the rough
Liu, JunZhang, KaidiShi, JunweiWu, JinglaiZhang, Yunqing
Centipedes are known for their wiggly walk. With tens to hundreds of legs, they can traverse any terrain without stopping.
The BS6 norms (phase 1) were implemented in India from April 1, 2020 and replaced the previous BS4 norms. Phase 2 of the BS6 norms, which came into effect on April 1, 2023. In accordance with the regulation requirement, effective performance of after treatment systems like DPF and SCR demands critical hardware implementation and robust monitoring strategies in the extended operating zone. Effective OBD monitoring of DPF, which is common to all BSVI certified vehicles, such that the defined strategy detects the presence or absence of the component is imperative. A robust monitoring strategy is developed to detect the presence of the DPF in the real world incorporating the worst possible driving conditions including idling, and irrespective of other environmental factors subject to a location or terrain. The differential pressure sensor across the DPF is used to study the actual pressure drop across the DPF. Additional for BS 6 (phase 2) PM sensor becomes an important part to keep the
Sharma, PrashantHareesh, SangarajuV, SuryanarayananPalanisamy, KrishnarajP, JagdesanRathiya, Akash
As a major checkpoint in worldwide Automotive Emission Regulations, the Real Drive Emission (RDE) has been introduced to regulate the amount of pollutants in real road driving conditions. Such tests depend very much on numerous ambient conditions, in which the altitude of the terrain is one major factor. Among the various vehicle exhaust pollutants, NOx, CO & CO2 have the tendency to vary in connection to the atmospheric ambient conditions where the vehicles are being operated. For an instance, in our targeted case of testing at higher altitudes CO & NOx levels are found to be higher than when tested at normal RDE regulatory altitude limits. As the altitude increases, the amount of oxygen present in the atmosphere decreases, which can cause the combustion process in an internal combustion engine to operate at a lesser efficient stoichiometric composition than at sea level. This will in-turn produce more exhaust emissions as a byproduct of such altered compensative functioning
Pallerla, SunilBalagangatharan, BalamuralitharanRajan, GauthamMuthrak, Raja Pramod Kumar
A team at NASA's Jet Propulsion Laboratory that's creating a snake-like robot for traversing extreme terrain is taking on the challenge with the mentality of a startup: Build quickly, test often, learn, adjust, repeat. Called EELS (short for Exobiology Extant Life Surveyor), the self-propelled, autonomous robot was inspired by a desire to look for signs of life in the ocean hiding below the icy crust of Saturn's moon Enceladus by descending narrow vents in the surface that spew geysers into space.
Velocity prediction on hilly road can be applied to the energy-saving predictive control of intelligent vehicles. However, the existing methods do not deeply analyze the difference and diversity of road slope driving characteristics, which affects prediction performance of some prediction method. To further improve the prediction performance on road slope, and different road slope driving features are fully exploited and integrated with the common prediction method. A rolling prediction-based multi-scale fusion prediction considering road slope transition driving characteristics is proposed in this study. Amounts of driving data in hilly sections were collected by the advanced technology and equipment. The Markov chain model was used to construct the velocity and acceleration joint state transition characteristics under each road slope transition pair, which expresses the obvious driving difference characteristics when the road slope changes. An algorithm was designed to satisfy
Zhang, ManHe, SiyuanPei, ZhenlongLin, Nan
Smart cars or autonomous vehicles have garnered significant attention in recent years due to their potential to alleviate traffic congestion, enhance road safety, and improve fuel efficiency. However, effectively navigating through complex terrains requires the implementation of an efficient path planning algorithm. Traditional path planning algorithms often face limitations when confronted with intricate terrains. This study focuses on analyzing the path planning problem for intelligent vehicles in complex terrains by utilizing the optimization evaluation function of the artificial bee colony (ABC) algorithm. Additionally, the impact of turning radius at different speeds is considered during the planning process. The findings indicate that the optimal number of control points varies depending on mission requirements and terrain conditions, necessitating a comparison to obtain the optimal value. Generally, reducing the number of control points facilitates smoother paths, while
Li, DaPengGu, RuiZheng, YujunZuo, Songchen
This paper describes a patented, standalone, intelligent Hill Drive Away Assist (HDAA) system, comprising of an electro-mechanical unit, to overcome the hurdles faced by the driver while starting the vehicle on a gradient. This system can be added as an additional feature in vehicles which have Manual or Automatic Transmission and are equipped with or without ABS (Antilock Braking System). The developed system is available as Hill Start Assist (HSA) feature in vehicles with Electronic Stability Control (ESC). This HSA functionality is achieved through Drive Away Release (DAR) feature in vehicles equipped with Electric Park Brake (EPB). In ABS only vehicles, this feature cannot be achieved with the existing hardware and software. This HDAA can be implemented as a stand-alone system in vehicles without ESC / EPB, thereby reducing the cost of the vehicle while providing the Hill Start feature. The HDAA is a driver friendly system, which aids the driver while trying to start a vehicle
Ramani, SudhaRamani, SriramBalasubramaniam, Ramthilak
In recent decades, significant technological advances have made cruise control systems safer, more automated, and available in more driving scenarios. However, comparatively little progress has been made in optimizing vehicle efficiency while in cruise control. In this paper, two distinct strategies are proposed to deliver efficiency benefits in cruise control by leveraging flexibility around the driver’s requested set speed, and road information that is available on-board in many new vehicles. In today’s cruise control systems, substantial energy is wasted by rigidly controlling to a single set speed regardless of the terrain or road conditions. Introducing even a small allowable “error band” around the set speed can allow the propulsion system to operate in a pseudo-steady state manner across most terrain. As long as the vehicle can remain in the allowed speed window, it can maintain a roughly constant load, traveling slower up hills and faster down hills. This strategy reduces the
Grewal, AmanpalZebiak, Matthew
Synthetic Aperture Radar (SAR) images are a powerful tool for studying the Earth’s surface. They are radar signals generated by an imaging system mounted on a platform such as an aircraft or satellite. As the platform moves, the system emits sequentially high-power electromagnetic waves through its antenna. The waves are then reflected by the Earth’s surface, re-captured by the antenna, and finally processed to create detailed images of the terrain below.
ABSTRACT In this investigation, a prototype tool for visualizing vehicle mobility and planning routes across offroad terrain was developed and evaluated in the field. The tool uses detailed vehicle, soil, and terrain characteristics to plan routes and indicate vehicle limits, including go/no-go zones on the local terrain map. Consistent with NG-NRMM principles, the process uses Multi-Body system simulation and simple terramechanics soil models to characterize the vehicle capability and integrate this data within a geospatial application to visualize mobility over terrain and facilitate route planning. A tablet-based prototype was soldier-tested in the field to confirm operational utility and selected routes. The results indicate how the NG-NRMM approach and associated modeling strategies can positively impact operational planning and execution. Citation: E. Pesheck, R. Goff, J. Little, P. Jayakumar, “Tool Development for Mobility Visualization and Routing Incorporating Vehicle
Pesheck, EricGoff, RobertLittle, JosephJayakumar, Paramsothy
ABSTRACT Geotechnical site characterization is the process of collecting geophysical and geospatial characteristics about the surface and subsurface to create a 3-dimensional (3D) model. Current Robot Operating System (ROS) world models are designed primarily for navigation in unknown environments; however, they do not store the geotechnical characteristics requisite for environmental assessment, archaeology, construction engineering, or disaster response. The automotive industry is researching High Definition (HD) Maps, which contain more information and are currently being used by autonomous vehicles for ground truth localization, but they are static and primarily used for navigation in highly regulated infrastructure. Modern site characterization and HD mapping methods involve survey engineers working on-site followed by lengthy post processing. This research addresses the shortcomings for current world models and site characterization by introducing Site Model Geospatial System
Richards, Matthew E.Murphy, Kevin F.Toledo, Israel LopezSoylemezoglu, Ahmet
A sparsely-encoded convolutional autoencoder architecture is proposed in this work for semantic segmentation of unknown terrain. The excellent feature extraction capabilities of the convolutional autoencoder (CAE) is utilized with the computation-efficient Echo State Network (ESN) for faster and efficient encoding, and semantic segmentation of unknown images. The proposed scheme manifests two CAEs trained with image and label data, and an ESN at the latent space of the two CAE to transform the encoded unknown image to semantic segmentation of different regions. The RUGD dataset of off-road images is used for training and validation of the proposed algorithm under variation of hyper-parameters. The proposed algorithm is implemented using Python and PyTorch, and simulation results demonstrate the effectiveness for semantic segmentation.
Haider, Mohammad R.Hoxie, DavidGardner, StevenMisko, SamuelJayakumar, ParamsothySmereka, JonathanWoten, Jake
Mobility in the Arctic often determines a military unit’s ability to accomplish mission objectives. This article provides fundamental characteristics and models that can be used to adapt military operations for Arctic and cold region terrain. It explains the need for mobility research in the Arctic, details the Arctic regional terrain types, common yet unique terrain surfaces of the Arctic, and the impact of seasonality on mobility. There is still much research to be done to advance mobility in the Arctic. The terrestrial science and basic modeling framework here provide the foundation to develop military operations, doctrine, and equipment solutions for the Arctic.
Shoop, SallyParker, MichaelOlivier, JasonGaribay, Edward A.
ABSTRACT Accurate terrain mapping is of paramount importance for motion planning and safe navigation in unstructured terrain. LIDAR sensors provide a modality, in the form of a 3D point cloud, that can be used to estimate the elevation map of the surrounding environment. But, working with the 3D point cloud data turns out to be challenging. This is primarily due to the unstructured nature of the point clouds, relative sparsity of the data points, occlusions due to negative slopes and obstacles, and the high computational burden of traditional point cloud algorithms. We tackle these problems with the help of a learning-based, efficient data processing approach for vehicle-centric terrain reconstruction using a 3D LIDAR. The 3D LIDAR point cloud is projected on the ground plane, which is processed by a generative adversarial network (GAN) architecture in the form of an image to fill in the missing parts of the terrain heightmap. We train the GAN model on artificially generated datasets
Sutavani, SarangZheng, AndrewJoglekar, AjinkyaSmereka, JonathonGorsich, DavidKrovi, VenkatVaidya, Umesh
Autonomous vehicle navigation requires signal processing of the vehicle’s sensors to provide meaningful information to the planners such that challenging artifacts like shadows, rare events, obstructive vegetation, etc. are identified properly, avoiding ill-informed navigation. Using a single algorithm such as semantic segmentation of camera images is often not enough to identify those challenging features but can be overcome by processing more than one type of sensor and fusing their results. In this work, semantic segmentation of camera image and LiDAR point cloud signals is performed using Echo State Networks to overcome the challenge of shadows identified as obstructions in off-road terrains. The coordination of algorithms processing multiple sensor signals is shown to avoid unnecessary road obstructions caused by high-contrast shadows for more informed navigational planning.
Gardner, S. D.Hoxie, D.Bowen, N.Misko, S.Haider, M. R.Smereka, J.Jayakumar, P.Vantsevich, V.
This paper proposes an MPC-RL-CBF control framework that leverages the individual strengths of MPC (Model Predictive Control) schemes and Deep RL (Reinforcement Learning) techniques. This allows using a model mismatched computationally inexpensive optimal controller with a compensating learning technique to handle the uncertainties in system dynamics and unknown external disturbances. The controller is evaluated in simulation for a vehicle tracking a path with a lane change, subjected to unknown crosswinds. The results show that the MPC-RL-CBF approach helps track the path better than the purely model-based approach and does so safely, through safety guided training. This framework can be extended to off-road driving controls under changing terrain types and properties, tire-terrain interaction behavior, steep slopes etc.
Gupta, PrakharJia, Yunyi
Autonomous Navigation (AN) in complex-heterogeneous environments is an unsolved issue for both commercial and defense Autonomous Vehicle (AV) applications: A) Based on accumulated data through 2021 there are on average 9.1 driverless car crashes per million miles driven compared to 4.1 human-driven car crashes. B)The US Army recently reduced the requirement for its current Bradley replacement program of record from an “optionally manned fighting vehicle” to a system that “will not be something you operate entirely unmanned in its initial configuration”. C) Between 2021 and 2023 Ford, UBER, Lyft and Tesla have limited their fully AV operations due to safety related business concerns. It is clear a research breakthrough is needed to ensure AV software is mature to a point where it can handle complex driving scenarios. In complex dynamic domains (e.g. intersections or congested terrain) the expected mode of operation for ensured safety of these unmanned systems is still direct human
Frederick, Philip A.
ABSTRACT Autonomous vehicles rely on path planning to guide them towards their destination. These paths are susceptible to interruption by impassable hazards detected at the local scale via on-board sensors, and malicious disruption. We define robustness as an additional parameter which can be incorporated into multi-objective optimization functions for path planning. The robustness at any point is the output of a function of the isochrone map at that point for a set travel time. The function calculates the sum of the difference in area between the isochrone map and the isochrone map with an impassable semi-circle hazard inserted in each of the four cardinal directions. We calculate and compare two different Pareto paths which use robustness as an input parameter with different weights. Citation: T. Jonsson Damgaard, M. Rittri, P. Franz, A. Halota “Robust Path Planning in the Battlefield,” In Proceedings of the Ground Vehicle Systems Engineering and Technology Symposium (GVSETS), NDIA
Damgaard, Thomas JonssonRittri, MikaelFranz, PatrickHalota, Anika
A team of researchers from the Department of Mechanical Science and Bioengineering at Osaka University have invented a new kind of walking robot that takes advantage of dynamic instability to navigate. By changing the flexibility of the couplings, the robot can be made to turn without the need for complex computational control systems. This work may assist the creation of rescue robots that are able to traverse uneven terrain.
Researchers from MIT’s Improbable Artificial Intelligence Lab, part of the Computer Science and Artificial Intelligence Laboratory (CSAIL), have developed a legged robotic system that can dribble a soccer ball under the same conditions as humans. The bot used a mixture of onboard sensing and computing to traverse different natural terrains such as sand, gravel, mud, and snow, and adapt to their varied impact on the ball’s motion. Like every committed athlete, “DribbleBot” could get up and recover the ball after falling.
Advances made in advanced driver assistance systems such as antilock braking systems (ABS) have significantly improved the safety of road vehicles. ABS enhances the braking and steerability of a vehicle under severe braking conditions. However, ABS performance degrades on rough roads. This is largely due to noisy measurements, the type of ABS control algorithm used, and the excitation of complex dynamics such as higher-order tire mode shapes that are neglected in the control strategy. This study proposes a model-free intelligent control technique with no modelling constraints that can overcome these unmodelled dynamics and parametric uncertainties. The double deep Q-learning network (DDQN) algorithm with the temporal convolutional network is presented as the intelligent control algorithm. The model is initially trained with a simplified single-wheel model. The initial training data are transferred to and then enhanced using a validated full-vehicle model including a physics-based tire
Abreu, RicardoBotha, Theunis R.Hamersma, Herman A.
This research examined tractor operators’ daily vibration exposure A(8) with different input riding parameters, i.e., average speed (m/s) (2.78, 3.89, 5.0), body mass (BM) (kg/m2) (35.3, 32.6, 25.4), and different terrain types (brick, farm, and tar roads). To arrange the systematic sequence of experiments, Taguchi’s L9 orthogonal array has been selected for this study. The signal-to-noise ratio (SNR) is calculated to analyze the overall influence of input parameters over the output parameters. In this study, it is found that A(8) responses exceeded the recommended action value among all the tractor operators according to ISO 2631-1 (1997). The average speeds and various terrain conditions were shown to be the most influential significant variables (p ≤ 0.05), with percentage contributions of 53.71% and 11.53%, respectively. The predicted linear and linear interaction values in a regression model are quite similar to the experimental values, with mean error percentages of 3.89% and
Prakash, ChanderSingh, Lakhwinder PalGupta, Ajay
This paper presents a comprehensive investigation aimed to assess the effect of tire inflation pressure on the fuel consumption of a typical 4×4 off-road vehicle over unprepared soft terrains. For this purpose, a fourteen-degrees-of-freedom (14-DOF) full parametrized vehicle model is employed and numerically simulated in MATLAB/Simulink™ environment. This model is intended to consider all the rotational dynamics and compliances of all-wheel-drivetrain aggregates using SimDriveline™ toolbox including engine, transmission, differentials, shafts and wheels. Numerous simulations are carried out to examine both the tractive efficiency and fuel consumption considering all power losses in transmission, terrains and tire slippage over different operating conditions such as terrain’s mechanical properties, tire weight distribution and drivetrain configurations (open or locked center differential). Furthermore, the fuel consumption is evaluated during two separate driving scenarios namely
Sharaf, Alhossein Mostafa
Image segmentation has historically been a technique for analyzing terrain for military autonomous vehicles. One of the weaknesses of image segmentation from camera data is that it lacks depth information, and it can be affected by environment lighting. Light detection and ranging (LiDAR) is an emerging technology in image segmentation that is able to estimate distances to the objects it detects. One advantage of LiDAR is the ability to gather accurate distances regardless of day, night, shadows, or glare. This study examines LiDAR and camera image segmentation fusion to improve an advanced driver-assistance systems (ADAS) algorithm for off-road autonomous military vehicles. The volume of points generated by LiDAR provides the vehicle with distance and spatial data surrounding the vehicle. Processing these point clouds with semantic segmentation is a computationally intensive process requiring fusion of camera and LiDAR data so that the neural network can process depth and image data
Faykus, Max HenrySelee, BradleySmith, Melissa
Autonomous vehicle navigation, both global and local, makes use of large amounts of multifactorial data from onboard sensors, prior information, and simulations to safely navigate a chosen terrain. Additionally, as each mission has a unique set of requirements, operational environment and vehicle capabilities, any fixed formulation for the cost associated with these attributes is sub-optimal across different missions. Much work has been done in the literature on finding the optimal cost definition and subsequent mission pathing given sufficient measurements of the preference over the mission factors. However, obtaining these measurements can be an arduous and computationally expensive task. Furthermore, the algorithms that utilize this large amount of multifactorial data themselves are time consuming and expensive. Often, it is valuable to make assessments about a terrain with limited information and using similarity with existing terrains without necessarily performing the entire
Mollan, CalahanPandey, VijitashwaPinapala, Amith
The physical characteristics of Mars's soil have an impact on how easily a spacecraft can land and navigate the planet's surface. On the surface of Mars, wheeled robots known as "rovers" were planted to carry out scientific investigations on the planet's historical temperature, surface geology, and possibilities for past or current life. The challenges of guiding mobile robots across terrain that is sloping, rocky, and deformable have brought to light the significance of creating precise simulation models of the tire and mars soil interaction. In this paper, current efforts to create a terramechanics-based model of rover movement using a Non-Pneumatic (NP) tire on planetary surfaces are discussed. Since no rocks or soils have been brought back to Earth from Mars, Martian simulants are frequently used for testing rovers and other devices for Mars terrain research. Using a Finite Element Analysis-based NP tire model that is modeled and tested, in addition to a dry loose Martian soil that
Sidhu, Charanpreet SinghEl-Sayegh, ZeinabLy, Alfonse
Traditional ground vehicle architectures comprise of a chassis connected via passive, semi-active, or active suspension systems to multiple ground wheels. Current design-optimizations of vehicle architectures for on-road applications have diminished their mobility and maneuverability in off-road settings. Autonomous Ground Vehicles (AGV) traversing off-road environments face numerous challenges concerning terrain roughness, soil hardness, uneven obstacle-filled terrain, and varying traction conditions. Numerous Active Articulated-Wheeled (AAW) vehicle architectures have emerged to permit AGVs to adapt to variable terrain conditions in various off-road application arenas (off-road, construction, mining, and space robotics). However, a comprehensive framework of AAW platforms for exploring various facets of system architecture/design, analysis (kinematics/dynamics), and control (motions/forces) remains challenging. While current literature on the AAW system incorporates modeling and
Mehta, DhruvKosaraju, Krishna ChaitanyaKrovi, Venkat N
The four-screw propulsion vehicle has high traffic performance and strong maneuverability on the fluidized soft terrain. However, the interaction mechanism between the four-screw vehicle and the soft terrain is quite complicated. The driving performance of the screw vehicle on the soft terrain are not clear, and it is difficult to achieve accurate dynamic control of the four-screw vehicle. The mechanical relationship and motion mode of the four-screw propulsion vehicle-soft terrain interaction are theoretical analyzed, the force characteristics of the screw drive wheel under each motion mode of the vehicle are obtained. The interaction model between soft terrain of tailings dam and four-screw vehicle is established by using smooth particle hydrodynamics (SPH) and finite element method (FEM). Four groups of different screw driving angular velocity and four groups of different screw angular velocity difference are selected to simulate the straight driving and differential steering in
Wang, KaidiShen, YanhuaLiu, TaoZhang, Haojie
Published data relevant to snowmobile crash reconstruction is comparatively limited, especially pertaining to mountain snowmobiling and riding in deep snow. Snowmobiling is a unique motorsport activity as it requires substantial rider input and physical interaction to properly control the vehicle. The added complexities of varying slope angle and snow depth in mountain terrain make application of test data from testing done on flat surfaces less useful when applied to sloped terrain analysis. New data from testing performed in deep snow conditions on various slopes is presented in this paper. Acceleration tests were performed using two late model mountain snowmobiles from a stop on various slope angles. Additional related factors such as snow density, trenching, and snow mass momentum exchange are also discussed. Comparison of these test results to previously published snowmobile testing data advances the understanding of snowmobile acceleration parameters into mountain terrain
Warner, WyattWarner, Mark
A research team led by Professor Jemin Hwangbo of the Department of Mechanical Engineering at KAIST has developed a quadrupedal robot control technology that can walk robustly with agility even in deformable terrain such as sandy beach.
Genesys Aerosystems, a Moog company, offers a line of avionics specifically designed for the military/special-mission market. Originally, the system was developed as part of the FAA's Capstone Program - first established in 1999 - to reduce the excessively high number of controlled flight into terrain (CFIT) accidents in the southeast region of Alaska. Implementation of this technology by pilots in the southeast Alaska region immediately reduced the CFIT accident rate from an average of one fatality every nine days to zero among commercial aircraft. Twenty years later, the Capstone equipment continues to provide exceptional safety, and Genesys has become a leading avionics supplier to military and special-mission fleet operators around the world, including the U.S. Navy, U.S. Army, and over 35 foreign militaries and other government operators.
Genesys Aerosystems, a Moog company, offers a line of avionics specifically designed for the military/special-mission market. Originally, the system was developed as part of the FAA’s Capstone Program — first established in 1999 — to reduce the excessively high number of controlled flight into terrain (CFIT) accidents in the southeast region of Alaska.
An interdisciplinary team of University of Minnesota Twin Cities scientists and engineers has developed a first-of-its-kind, plant-inspired extrusion process that enables synthetic material growth. The new approach will allow researchers to build better soft robots that can navigate hard-to-reach places, complicated terrain, and potentially areas within the human body.
The future battlefield will be filled with multiple dissimilar energy networks including unmanned and manned vehicular platforms actively engaged in cooperative control and communications capable of overpowering an adversary and dominating the battlespace. This chaotic multi-domain operational environment will be limited by variable operating conditions (mission profiles, terrain, atmospheric conditions), copious amounts of real-time actionable intelligence derived from weapon and sensor suites, and most importantly, the energy capabilities of each platform.
ABSTRACT To advance development of the off-road autonomous vehicle technology, software simulations are often used as virtual testbeds for vehicle operation. However, this approach requires realistic simulations of natural conditions, which is quite challenging. Specifically, adverse driving conditions, such as snow and ice, are notoriously difficult to simulate realistically. The snow simulations are important for two reasons. One is mechanical properties of snow, which are important for vehicle-snow interactions and estimation of route drivability. The second one is simulation of sensor responses from a snow surface, which plays a major role in terrain classification and depends on snow texture. The presented work describes an overview of several approaches for realistic simulation of snow surface texture. The results indicate that the overall best approach is the one based on the Wiener–Khinchin theorem, while an alternative approach based on the Cholesky decomposition is the second
Vecherin, SergeyMeyer, AaronQuinn, BrianLetcher, TheodoreParker, Michael
ABSTRACT All-Terrain off-road environments are the next frontier for autonomous vehicles to overcome. However, there are many obstacles in the way of this goal. Artificial intelligence has proven to be an invaluable asset in developing perception and path planning systems capable of overcoming these obstacles, but these AI systems fundamentally rely on the availability of data related to the operational environment in order to succeed. Currently, there is no unifying ontology for this data. This has inhibited progress on training AI by reducing the availability of cross-integrable datasets. We present ATLAS: A labeling ontology composed of over 200 labels specifically designed to encompass all-terrain off-road environments. This ontology will lay the ground work for creating scalable standardized all terrain off-road data and will enable future AI by providing an expansive and well labeled ontology that can push the field of autonomous vehicles to new heights. Citation: W. Smith, D
Smith, WestonGrabowsky, DavidMikulski, Dariusz
ABSTRACT This paper presents a Gaussian process model of terrain slope for use in a GPS-free localization algorithm for ground robots operating in unstructured terrain. A wheeled skid-steer robot is used to map the terrain slope within an operational area of interest. The slope data is sampled sparsely and used as training data for a Gaussian process model with a two-dimensional input. Three different covariance functions for the Gaussian process model are evaluated with hyperparameters selected through maximizing the log marginal likelihood. The resulting Gaussian process model is used in the measurement update function of a localization particle filter to generate expected slope values at particle positions. Preliminary localization testing shows sub-ten meter accuracy with no initial knowledge of position. However, the overall performance of the filter is highly dependent on the variability of the terrain that the robot traverses. Citation: J. Pentzer, K. Reichard, “Gaussian Process
Pentzer, JesseReichard, Karl
ABSTRACT This paper presents a new terrain traversability mapping method integrated into the Robotic Technology Kernel (RTK) that produces ground slope traversability cost information from LiDAR height maps. These ground slope maps are robust to a variety of off-road scenarios including areas of sparse or dense vegetation. A few simple and computationally efficient heuristics are applied to the ground slope maps to produce cost data that can be directly consumed by existing path planners in RTK, improving the navigation performance in the presence of steep terrain. Citation: J. Ramsey, R. Brothers, J. Hernandez, “Creation of a Ground Slope Mapping Methodology Within the Robotic Technology Kernel for Improved Navigation Performance,” In Proceedings of the Ground Vehicle Systems Engineering and Technology Symposium (GVSETS), NDIA, Novi, MI, Aug. 16-18, 2022.
Ramsey, JacksonBrothers, RobertHernandez, Joseph
ABSTRACT Many rollover prevention algorithms rely on vehicle models which are difficult to develop and require extensive knowledge of the vehicle. The Zero-Moment Point (ZMP) combines a simple vehicle model with IMU-only sensor measurements. When used in conjunction with haptic feedback, ground vehicle rollover can be prevented. This paper investigates IMU grade requirements for an accurate rollover prediction. This paper also discusses a haptic feedback design that delivers operator alerts to prevent rollover. An experiment was conducted using a Gazebo simulation to assess the capabilities of the ZMP method to predict vehicle wheel lift-off and demonstrate the potential for haptic communication of the ZMP index to prevent rollover. Citation: K. Steadman, C. Stubbs, A. Baskaran, C. G. Rose, D. Bevly, “Teleoperated Ground Vehicle Rollover Prevention via Haptic Feedback of the Zero-Moment Point Index,” In Proceedings of the Ground Vehicle Systems Engineering and Technology Symposium
Steadman, KathleenStubbs, ChandlerBaskaran, AvinashRose, Chad G.Bevly, David
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