scholarly journals Research on Developing an Outdoor Location System Based on the Ultra-Wideband Technology

Sensors ◽  
2020 ◽  
Vol 20 (21) ◽  
pp. 6171
Author(s):  
Łukasz Rykała ◽  
Andrzej Typiak ◽  
Rafał Typiak
Keyword(s):  
Communication Technologies ◽  
Ultra Wideband ◽  
Unmanned Ground Vehicle ◽  
Ground Vehicle ◽  
Localization Algorithms ◽  
Multipath Effects ◽  
Outdoor Environments ◽  
Uwb Applications ◽  
Outdoor Location ◽  
Selection Of

Ultra-wideband (UWB) technology is one of the most promising wireless communication technologies. Examples of UWB applications include, among others, radiocommunication devices and location systems, due to their operating range, ability to work in outdoor environments, and resistance to multipath effects. This article focuses on the use of UWB technology in constructing a guide localization system for an unmanned ground vehicle (UGV), which is one of the stages of implementing a “follow me” system. This article describes the complete process of UWB signal processing from its acquisition, methods of filtering, and obtained results, to determining the location of the guide. This article examines the possibility of using modified versions of localization algorithms for determining the guide’s location, including trilateration, methods of nonlinear programming, and a geometric algorithm proposed by us. The innovation of this study consists in the implementation of an algorithm that changes the selection of equations (mathematical model) for determining location based on the number of available measurements from UWB sensors.

Water Hazard Detection Based on 3D LIDAR

2014 ◽  
Vol 668-669 ◽  
pp. 1174-1177 ◽  
Author(s):  
Hai Yan Shao ◽  
Zhen Hai Zhang ◽  
Ke Jie Li ◽  
Jian Wang ◽  
Tao Xu ◽  
...  
Keyword(s):  
Unmanned Ground Vehicle ◽  
Data Format ◽  
Ground Vehicle ◽  
Air Water Interface ◽  
Water Hazard ◽  
Outdoor Environments ◽  
Bodies Of Water ◽  
3D Lidar ◽  
Water Hazards ◽  
Complicated Task

Autonomous off-road navigation is a highly complicated task for a robot or unmanned ground vehicle (UGV) owing to the different kinds of obstacles it could encounter. In-particular, water hazards such as puddles and ponds are very common in outdoor environments and are hard to detect even with ranging devices due to the specular nature of reflection at the air water interface. In recent years, many researches to detect the water bodies have been done. But there still has been very little work on detecting bodies of water that could be navigation hazards, especially at night. In this paper, we used Velodyne HDL-64ES2 3D LIDAR to detect water hazard. The approach first analyzes the data format and transformation of 3D LIDAR, and then writes the data acquisition and visualizations algorithm, integrated data based on ICP algorithm. Finally according the intensity distribution identifies the water hazard. Experiments are carried out on the experimental car in campus, and results show the promising performance.

Mobile Robot Decision-Making Based on Offline Simulation for Navigation over Uneven Terrain

2018 ◽  
Vol 30 (4) ◽  
pp. 671-682
Author(s):  
Yuichi Kobayashi ◽  
Masato Kondo ◽  
Yuji Hiramatsu ◽  
Hokuto Fujii ◽  
Tsuyoshi Kamiya ◽  
...  
Keyword(s):  
Mobile Robot ◽  
Path Selection ◽  
Outdoor Environment ◽  
Selection Strategy ◽  
Unmanned Ground Vehicle ◽  
Ground Vehicle ◽  
Uneven Terrain ◽  
Simulated Environment ◽  
Terrain Features ◽  
Selection Of

This paper presents an action decision framework for an autonomous mobile robot or an unmanned ground vehicle (UGV) to navigate an unknown environment. It is difficult for a UGV without global map information to decide which path to travel when it comes to a fork. However, locally observed terrain features can enable the UGV if it can utilize its past experience. The proposed path selection method utilizes correlations between features of the local terrain obtained by its laser range finder and the values of paths obtained through offline simulation using global path planning. During navigation, the UGV estimates the values of each path at a fork based on the correlation between the terrain feature and the value. It was confirmed that the proposed method allows the selection of paths that are more effective compared with a simple path selection strategy with which the UGV selects the closer path to the goal. The proposed method was evaluated in both a simulated environment and a real outdoor environment.

A Tracked Double-Bodied Vehicle for Use in Outdoor Environments

2017 ◽  
Author(s):  
Michael Benson ◽  
Garrett M. Clayton
Keyword(s):  
Vehicle Dynamics ◽  
Nonlinear Models ◽  
Computation Time ◽  
Contact Forces ◽  
Unmanned Ground Vehicle ◽  
Ground Vehicle ◽  
Surface Conditions ◽  
Outdoor Environments ◽  
Fixed Axis ◽  
Two Bodies

This paper presents an unmanned ground vehicle for use in outdoor environments. The vehicle features a two-bodied design in which the two bodies can rotate relative to each other about a fixed axis. The vehicle uses tracked locomotion for performance in rugged environments and a linear actuator for control of the bodys’ relative orientation. A spring-damper is used to mitigate vibrations due to surface conditions that would add noise to the sensors. A nonlinear model for the vehicle is introduced, and linearized. Design considerations of the suspension system are discussed, including the reduction of vibrations and the maximization of contact forces. Finally, the vehicle dynamics are simulated for the linear and nonlinear models, and the effectiveness and computation time of the two are compared.

scholarly journals An Imaging Network Design for UGV-Based 3D Reconstruction of Buildings

2021 ◽  
Vol 13 (10) ◽  
pp. 1923
Author(s):  
Ali Hosseininaveh ◽  
Fabio Remondino
Keyword(s):  
3D Reconstruction ◽  
Network Design ◽  
Real World ◽  
Continuous Image ◽  
Unmanned Ground Vehicle ◽  
Ground Vehicle ◽  
Localization And Mapping ◽  
Image Capturing ◽  
Slam Algorithm ◽  
Selection Of

Imaging network design is a crucial step in most image-based 3D reconstruction applications based on Structure from Motion (SfM) and multi-view stereo (MVS) methods. This paper proposes a novel photogrammetric algorithm for imaging network design for building 3D reconstruction purposes. The proposed methodology consists of two main steps: (i) the generation of candidate viewpoints and (ii) the clustering and selection of vantage viewpoints. The first step includes the identification of initial candidate viewpoints, selecting the candidate viewpoints in the optimum range, and defining viewpoint direction stages. In the second step, four challenging approaches—named façade pointing, centre pointing, hybrid, and both centre & façade pointing—are proposed. The entire methodology is implemented and evaluated in both simulation and real-world experiments. In the simulation experiment, a building and its environment are computer-generated in the ROS (Robot Operating System) Gazebo environment and a map is created by using a simulated robot and Gmapping algorithm based on a Simultaneously Localization and Mapping (SLAM) algorithm using a simulated Unmanned Ground Vehicle (UGV). In the real-world experiment, the proposed methodology is evaluated for all four approaches for a real building with two common approaches, called continuous image capturing and continuous image capturing & clustering and selection approaches. The results of both evaluations reveal that the fusion of centre & façade pointing approach is more efficient than all other approaches in terms of both accuracy and completeness criteria.

scholarly journals Scoring Cercospora Leaf Spot on Sugar Beet: Comparison of UGV and UAV Phenotyping Systems

2020 ◽  
Vol 2020 ◽  
pp. 1-18 ◽  
Author(s):  
S. Jay ◽  
A. Comar ◽  
R. Benicio ◽  
J. Beauvois ◽  
D. Dutartre ◽  
...  
Keyword(s):  
Sugar Beet ◽  
Leaf Spot ◽  
Spot Size ◽  
Unmanned Ground Vehicle ◽  
Cercospora Leaf Spot ◽  
Ground Vehicle ◽  
Aerial Vehicle ◽  
High Throughput Phenotyping ◽  
Selection Of ◽  
Genotype Sensitivity

Selection of sugar beet (Beta vulgaris L.) cultivars that are resistant to Cercospora Leaf Spot (CLS) disease is critical to increase yield. Such selection requires an automatic, fast, and objective method to assess CLS severity on thousands of cultivars in the field. For this purpose, we compare the use of submillimeter scale RGB imagery acquired from an Unmanned Ground Vehicle (UGV) under active illumination and centimeter scale multispectral imagery acquired from an Unmanned Aerial Vehicle (UAV) under passive illumination. Several variables are extracted from the images (spot density and spot size for UGV, green fraction for UGV and UAV) and related to visual scores assessed by an expert. Results show that spot density and green fraction are critical variables to assess low and high CLS severities, respectively, which emphasizes the importance of having submillimeter images to early detect CLS in field conditions. Genotype sensitivity to CLS can then be accurately retrieved based on time integrals of UGV- and UAV-derived scores. While UGV shows the best estimation performance, UAV can show accurate estimates of cultivar sensitivity if the data are properly acquired. Advantages and limitations of UGV, UAV, and visual scoring methods are finally discussed in the perspective of high-throughput phenotyping.

Design and experimental characterization of an omnidirectional unmanned ground vehicle for unstructured terrain

Robotica ◽  
2014 ◽  
Vol 33 (9) ◽  
pp. 1984-2000
Author(s):  
Chenghui Nie ◽  
Marin Assaliyski ◽  
Matthew Spenko
Keyword(s):  
Energy Consumption ◽  
Real World ◽  
Experimental Validation ◽  
Mechanical Design ◽  
Unmanned Ground Vehicle ◽  
Experimental Characterization ◽  
Ground Vehicle ◽  
Confined Spaces ◽  
Outdoor Environments

SUMMARYThis paper describes the design and experimental validation of an omnidirectional unmanned ground vehicle built for operation on real-world, unstructured terrains. The omnidirectional capabilities of this robot give it advantages over skid-steered or Ackermann-steered vehicles in tight and confined spaces. The robot's conventional wheels allow for operation in natural, outdoor environments as compared to omnidirectional robots that use specialized wheels with small, slender rollers and parts that can easily become obstructed with debris and dirt. Additionally, the robot's active split offset caster design allows the robot to kinematically follow continuous but non-differentiable paths and heading angles regardless of its current kinematic configuration. The active split offset caster design also results in less scrubbing torque and therefore less energy consumption during steering as compared to actively steered caster designs. The focus of this paper is the robot's mechanical design as it relates to kinematic isotropy and experimental validation of the design.

Design and Realization of an All-terrain Unmanned Ground Vehicle

ROBOT ◽  
2013 ◽  
Vol 35 (6) ◽  
pp. 657 ◽  
Author(s):  
Taoyi ZHANG ◽  
Tianmiao WANG ◽  
Yao WU ◽  
Qiteng ZHAO
Keyword(s):  
Unmanned Ground Vehicle ◽  
Ground Vehicle
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