358 research outputs found
INS/GPS/LiDAR integrated navigation system for urban and indoor environments using hybrid scan matching algorithm
This paper takes advantage of the complementary characteristics of Global Positioning System (GPS) and Light Detection and Ranging (LiDAR) to provide periodic corrections to Inertial Navigation System (INS) alternatively in different environmental conditions. In open sky, where GPS signals are available and LiDAR measurements are sparse, GPS is integrated with INS. Meanwhile, in confined outdoor environments and indoors, where GPS is unreliable or unavailable and LiDAR measurements are rich, LiDAR replaces GPS to integrate with INS. This paper also proposes an innovative hybrid scan matching algorithm that combines the feature-based scan matching method and Iterative Closest Point (ICP) based scan matching method. The algorithm can work and transit between two modes depending on the number of matched line features over two scans, thus achieving efficiency and robustness concurrently. Two integration schemes of INS and LiDAR with hybrid scan matching algorithm are implemented and compared. Real experiments are performed on an Unmanned Ground Vehicle (UGV) for both outdoor and indoor environments. Experimental results show that the multi-sensor integrated system can remain sub-meter navigation accuracy during the whole trajectory
PCA-based line detection from range data for mapping and localization-aiding of UAVs
This paper presents an original technique for robust detection of line features from range data, which is also the core element of an algorithm conceived for mapping 2D environments. A new approach is also discussed to improve the accuracy of position and attitude estimates of the localization by feeding back angular information extracted from the detected edges in the updating map. The innovative aspects of the line detection algorithm regard the proposed hierarchical clusterization method for segmentation. Instead, line fitting is carried out by exploiting the Principal Component Analysis, unlike traditional techniques relying on Least Squares linear regression. Numerical simulations are purposely conceived to compare these approaches for line fitting. Results demonstrate the applicability of the proposed technique as it provides comparable performance in terms of computational load and accuracy compared to the least squares method. Also, performance of the overall line detection architecture, as well as of the solutions proposed for line-based mapping and localization-aiding is evaluated exploiting real range data acquired in indoor environments using an UTM-30LX-EW 2D LIDAR. This paper lies in the framework of autonomous navigation of unmanned vehicles moving in complex 2D areas, e.g. unexplored, full of obstacles, GPS-challenging or denied
Simultaneous Localization and Mapping (SLAM) for Autonomous Driving: Concept and Analysis
The Simultaneous Localization and Mapping (SLAM) technique has achieved astonishing progress over the last few decades and has generated considerable interest in the autonomous driving community. With its conceptual roots in navigation and mapping, SLAM outperforms some traditional positioning and localization techniques since it can support more reliable and robust localization, planning, and controlling to meet some key criteria for autonomous driving. In this study the authors first give an overview of the different SLAM implementation approaches and then discuss the applications of SLAM for autonomous driving with respect to different driving scenarios, vehicle system components and the characteristics of the SLAM approaches. The authors then discuss some challenging issues and current solutions when applying SLAM for autonomous driving. Some quantitative quality analysis means to evaluate the characteristics and performance of SLAM systems and to monitor the risk in SLAM estimation are reviewed. In addition, this study describes a real-world road test to demonstrate a multi-sensor-based modernized SLAM procedure for autonomous driving. The numerical results show that a high-precision 3D point cloud map can be generated by the SLAM procedure with the integration of Lidar and GNSS/INS. Online four–five cm accuracy localization solution can be achieved based on this pre-generated map and online Lidar scan matching with a tightly fused inertial system
Scan matching by cross-correlation and differential evolution
Scan matching is an important task, solved in the context of many high-level problems including pose estimation, indoor localization, simultaneous localization and mapping and others. Methods that are accurate and adaptive and at the same time computationally efficient are required to enable location-based services in autonomous mobile devices. Such devices usually have a wide range of high-resolution sensors but only a limited processing power and constrained energy supply. This work introduces a novel high-level scan matching strategy that uses a combination of two advanced algorithms recently used in this field: cross-correlation and differential evolution. The cross-correlation between two laser range scans is used as an efficient measure of scan alignment and the differential evolution algorithm is used to search for the parameters of a transformation that aligns the scans. The proposed method was experimentally validated and showed good ability to match laser range scans taken shortly after each other and an excellent ability to match laser range scans taken with longer time intervals between them.Web of Science88art. no. 85
A Comprehensive Review on Autonomous Navigation
The field of autonomous mobile robots has undergone dramatic advancements
over the past decades. Despite achieving important milestones, several
challenges are yet to be addressed. Aggregating the achievements of the robotic
community as survey papers is vital to keep the track of current
state-of-the-art and the challenges that must be tackled in the future. This
paper tries to provide a comprehensive review of autonomous mobile robots
covering topics such as sensor types, mobile robot platforms, simulation tools,
path planning and following, sensor fusion methods, obstacle avoidance, and
SLAM. The urge to present a survey paper is twofold. First, autonomous
navigation field evolves fast so writing survey papers regularly is crucial to
keep the research community well-aware of the current status of this field.
Second, deep learning methods have revolutionized many fields including
autonomous navigation. Therefore, it is necessary to give an appropriate
treatment of the role of deep learning in autonomous navigation as well which
is covered in this paper. Future works and research gaps will also be
discussed
A review of system integration and current integrity monitoring methods for positioning in intelligent transport systems
Applications of intelligent transportation systems are continuously increasing. Since positioning is a key component in these systems, it is essential to ensure its reliability and robustness, and monitor its integrity so that the required levels of positioning accuracy, integrity, continuity and availability can be maintained. In challenging environments, such as urban areas, a single navigation system is often difficult to fulfil the positioning requirements. Therefore, integrating different navigation sensors becomes intrinsic, which may include the global navigation satellite systems, the inertial navigation systems, the odometers and the light detection and ranging sensors. To bind the positioning errors within a pre-defined integrity risk, the integrity monitoring is an essential step in the positioning service, which needs to be fulfilled for integrated vehicular navigation systems used in intelligent transportation systems. Developing such innovative integrity monitoring techniques requires knowledge of many relevant aspects including the structure, positioning methodology and different errors affecting the positioning solution of the individual and integrated systems. Moreover, knowledge is needed for the current mitigation techniques of these errors, for possible fault detection and exclusion algorithms and for computation of protection levels. This paper provides an overview and discussion of these aspects with a focus on intelligent transportation systems
TERRAIN-BASED NAVIGATION: A TOOL TO IMPROVE NAVIGATION AND FEATURE EXTRACTION PERFORMANCE OF MOBILE MAPPING SYSTEMS
Terrain-referenced navigation (TRN) techniques are of increasing interest in the research community, as they can provide alternative navigation tools when GPS is not available or the GPS signals are jammed. Some form of augmentation to cope with the lack of GPS signals is typically required in mobile mapping applications in urban canyons and is of interest for military applications. TRN could provide alternative position and attitude fixes to support an inertial navigation system, since such systems inevitably drift over time if not calibrated by GPS or other methodologies. With improving imaging sensor performance as well as growing worldwide availability of terrain high-resolution data and city models, terrain-based navigation is becoming a viable option to support navigation in GPS-denied environments. Furthermore, the feedback from the imaging sensors can be used even during GPS availability, which increases the redundancy of the measurement update step of the navigation filter, enabling more reliable integrity monitoring at this stage. The relevance of TRN to mobile mapping applications is twofold: (1) the process of obtaining real-time position and attitude fixes for the navigation filter is based on feature extraction, and, in particular, on the capability to separate the static and dynamic objects from the image data, and (2) the use of already available terrain data, including surface models (DSM), raster or vector data in CAD/GIS environments, such as city models, can effectively support the extraction processes. These two tasks could overlap, although the separation of the static and dynamic objects should work without any terrain data, and in fact, this is, to a large extent, the idea behind the removal of vehicles (moving objects) from imagery. The overall TRN concept, where LiDAR and optical imagery are matched with the existing terrain data is discussed and initial performance results are reported
Enhancing State Estimator for Autonomous Race Car : Leveraging Multi-modal System and Managing Computing Resources
This paper introduces an innovative approach to enhance the state estimator
for high-speed autonomous race cars, addressing challenges related to
unreliable measurements, localization failures, and computing resource
management. The proposed robust localization system utilizes a Bayesian-based
probabilistic approach to evaluate multimodal measurements, ensuring the use of
credible data for accurate and reliable localization, even in harsh racing
conditions. To tackle potential localization failures during intense racing, we
present a resilient navigation system. This system enables the race car to
continue track-following by leveraging direct perception information in
planning and execution, ensuring continuous performance despite localization
disruptions. Efficient computing resource management is critical to avoid
overload and system failure. We optimize computing resources using an efficient
LiDAR-based state estimation method. Leveraging CUDA programming and GPU
acceleration, we perform nearest points search and covariance computation
efficiently, overcoming CPU bottlenecks. Real-world and simulation tests
validate the system's performance and resilience. The proposed approach
successfully recovers from failures, effectively preventing accidents and
ensuring race car safety.Comment: arXiv admin note: text overlap with arXiv:2207.1223
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