| 1. |
- Banerjee, Avijit, et al.
(författare)
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On the Design, Modeling and Experimental Verification of a Floating Satellite Platform
- 2022
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Ingår i: IEEE Robotics and Automation Letters. - : IEEE. - 2377-3766. ; 7:2, s. 1364-1371
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Tidskriftsartikel (refereegranskat)abstract
- In this letter, a floating robotic emulation platform is presented with an autonomous maneuverability for a virtual demonstration of a satellite motion. Such a robotic platform design is characterized by its friction-less, levitating, yet planar motion over a hyper-smooth surface. The design of the robotic platform, integrated with the sensor and actuator units, is briefly described, including the related component specification along with the mathematical model, describing its dynamic motion. Additionally, the article establishes a nonlinear optimal control architecture consisting of a unified model predictive approach for the overall manoeuvre tracking. The efficacy of the proposed modeling and control scheme is demonstrated in multiple experimental studies, where it is depicted that the proposed controller has the potential to address a precise point-to-point manoeuvre with terminal objectives, as well as an excellent path following capability. The proposed design is validated with extensive experimental studies, and it is supported with related results.
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| 2. |
- Banerjee, Avijit, et al.
(författare)
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Resiliency in Space Autonomy: a Review
- 2023
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Ingår i: Current Robotics Reports. - : Springer. - 2662-4087. ; 4, s. 1-12
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Forskningsöversikt (refereegranskat)abstract
- Purpose of Review: The article provides an extensive overview on the resilient autonomy advances made across various missions, orbital or deep-space, that captures the current research approaches while investigating the possible future direction of resiliency in space autonomy.Recent Findings: In recent years, the need for several automated operations in space applications has been rising, that ranges from the following: spacecraft proximity operations, navigation and some station keeping applications, entry, decent and landing, planetary surface exploration, etc. Also, with the rise of miniaturization concepts in spacecraft, advanced missions with multiple spacecraft platforms introduce more complex behaviours and interactions within the agents, which drives the need for higher levels of autonomy and accommodating collaborative behaviour coupled with robustness to counter unforeseen uncertainties. This collective behaviour is now referred to as resiliency in autonomy. As space missions are getting more and more complex, for example applications where a platform physically interacts with non-cooperative space objects (debris) or planetary bodies coupled with hostile, unpredictable, and extreme environments, there is a rising need for resilient autonomy solutions.Summary: Resilience with its key attributes of robustness, redundancy and resourcefulness will lead toward new and enhanced mission paradigms of space missions.
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| 3. |
- Castro, Marley, et al.
(författare)
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Multi-Cubesat Mission For Auroral Acceleration Region Studies
- 2021
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Ingår i: IAC 2021 Congress Proceedings, 72nd International Astronautical Congress (IAC), Dubai, United Arab Emirates. - : International Astronautical Federation (IAF).
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Konferensbidrag (refereegranskat)abstract
- The Auroral Acceleration Region (AAR) is a key region in understanding the Magnetosphere-Ionosphere interaction. To understand the physical, spatial and temporal features of the region, multi-point measurements are required. Distributed small-satellite missions such as constellations of multiple nano satellites (for example multi-unit CubeSats) would enable such type of measurements. The capabilities of such a mission will highly depend on the number of satellites - one reason that makes low-cost platforms like CubeSats a very promising choice. In a previous study, the state-of-the-art of miniaturized payloads for AAR measurements was analyzed and evaluated and capabilities of different multi-CubeSat configurations equipped with such payloads in addressing different open questions in AAR were discussed. In this paper the mission analysis and possible mission design, as well as necessary technology developments of such multi-CubeSat mission are identified and presented.
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| 4. |
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| 5. |
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| 6. |
- Kottayam Viswanathan, Vignesh, et al.
(författare)
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Experimental Evaluation of a Geometry-Aware Aerial Visual Inspection Framework in a Constrained Environment
- 2022
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Ingår i: 2022 30th Mediterranean Conference on Control and Automation (MED). - : IEEE. - 9781665406734 - 9781665406741 ; , s. 468-474
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Konferensbidrag (refereegranskat)abstract
- This article aims to present an experimental evaluation of an offline, geometry-aware aerial visual inspection framework, specifically in constrained environment, established for geometrically fractured objects, by employing an autonomous unmanned aerial vehicle (UAV), equipped with on-board sensors. Based on a model-centric approach, the proposed inspection framework, generates inspection viewpoints around the geometrically fractured object, subject to the augmented static bounds to prevent collisions. The novel framework of visual inspection, presented in this article, aims to mitigate challenges arising due to the spatially-constrained environment, such as limited configuration space and collision with the object under inspection, by accounting for the geometrical information of the vehicle to be inspected. The efficacy of the proposed scheme is experimentally evaluated through large scale field trials with a mining machine.
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| 7. |
- Kottayam Viswanathan, Vignesh, et al.
(författare)
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First-look enabled Autonomous Aerial Visual Inspection of Geometrically Fractured Objects in Constrained Environments
- 2022
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Ingår i: 2022 IEEE 31st International Symposium on Industrial Electronics (ISIE). - : IEEE. ; , s. 295-300
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Konferensbidrag (refereegranskat)abstract
- In this article we propose a novel offline, model-based aerial visual inspection scheme for geometrically fractured large objects, based on fully autonomous Unmanned Aerial Ve-hicles (UAV s), while specifically targeting the case of constrained environments. The proposed framework enables a safe and collision free inspection mission, while guaranteeing a complete visual inspection of the object of interest. The proposed framework employs a novel First - Look approach to generate viewpoints satisfying specific photogrammetric requirements, as well as spatial constraints that are inherently applied by the UAV's state constraints. As it will be presented, i) the First - Look approach allows the UAV to first orient it's view vector towards the nearest available point detected by kd - tree based Nearest Neighbour search on the object, from it's current position, and ii) in the sequel, based on the orientation of the left vector of the camera and the overlap distance, the next viewpoint is projected. This approach is repeated throughout the whole inspection procedure, while the established framework has also the merit to ensure that the inspection path adapts to the shape of the object, which is highly advantageous for the cases of geometrically fractured objects. Multiple realistic and physics based simulation results are presented that prove the efficacy of the proposed scheme.
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| 8. |
- Kottayam Viswanathan, Vignesh, et al.
(författare)
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FLIE: First-Look Enabled Inspect-Explore Autonomy Toward Visual Inspection of Unknown Distributed and Discontinuous Structures
- 2023
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Ingår i: IEEE Access. - : IEEE. - 2169-3536. ; 11, s. 28140-28150
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Tidskriftsartikel (refereegranskat)abstract
- In this article, the problem of an online autonomous aerial inspection, specifically for discontinuous and distributed objects is presented. The proposed approach imposes view culling and photogrammetric constraints based on a geometrically modeled three-dimensional view pyramid, a view cone to filter surfaces by desired observation angle, a framework-integrated passive collision-avoidance scheme with the object under inspection, and a dynamically enveloping bounding-box region to map the visited surfaces. Furthermore, the proposed inspect-explore framework is validated for the case of an unknown environment with no prior knowledge of the object model under inspection. The overall inspection scheme is based on the novel First-Look approach, enabling the UAV to progressively adapt its inspection path to match the profile of the structure autonomously. The implemented exploration strategy imposes a tiered policy enabling the UAV to search, identify and navigate towards the structure for inspection. The presented work utilizes a unified architecture of the aforementioned inspect-explore framework to improve situational awareness in a previously unknown environment by enabling the UAV to explore its surrounding space and identify structures to execute closer inspection tasks. Extended simulations to evaluate the efficacy of the proposed inspect-explore framework are presented with multiple structure scenarios.
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| 9. |
- Kottayam Viswanathan, Vignesh, et al.
(författare)
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Nonlinear Model Predictive Control based Cooperative Stereo-Visual Coverage of an Asteroid
- 2022
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Ingår i: Proceedings of the 2022 American Control Conference (ACC). - : IEEE. ; , s. 5360-5367
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Konferensbidrag (refereegranskat)abstract
- In this article, a 3D visual coverage problem of an asteroid by establishing a stereo-visual based sensor from monocular cameras is considered. The cameras are individually mounted on two small low-thrust spacecraft, which are maintained in a tight stereo formation using a nonlinear model predictive control scheme to maintain an overlapping field-of-view and a specific baseline distance. The proposed control algorithm adopts a leader-follower architecture to define the relative pose between the spacecraft. However, asteroids provide a challenging environment for such missions deriving from their slow rotation rate and irregular shape. As such, they generate a low-order but irregular gravitational field. Paired with the influence of the solar radiation pressure acting on the spacecraft, the dynamic environment near the asteroid is highly perturbed. In addition, gravitational torque generated by the rotating body is also accounted for as it has a coupling effect between the orbital and attitude dynamics of the spacecraft. As a result, this article considers a full-state nonlinear control approach to plan correction maneuvers to maintain the desired pose of the spacecraft. The efficacy of the proposed control scheme is demonstrated within a realistic simulation scenario where the results are visualized utilizing the GAZEBO simulation environment.
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| 10. |
- Kottayam Viswanathan, Vignesh, et al.
(författare)
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Towards a Reduced Dependency Framework for Autonomous Unified Inspect-Explore Missions
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Annan publikation (övrigt vetenskapligt/konstnärligt)abstract
- The task of establishing and maintaining situational awareness in an unknown environment is a critical step to fulfil in a mission related to the field of rescue robotics. Predominantly, the problem of visual inspection of urban structures is dealt with view-planning being addressed by map-based approaches. In this article, we propose a novel approach towards effective use of Micro Aerial Vehicles (MAVs) for obtaining a 3-D shape of an unknown structure of objects utilizing a map-independent planning framework. The problem is undertaken via a bifurcated approach to address the task of executing a closer inspection of detected structures with a wider exploration strategy to identify and locate nearby structures, while being equipped with limited sensing capability. The proposed framework is evaluated experimentally in a controlled indoor environment in presence of a mock-up environment validating the efficacy of the proposed inspect-explore policy.
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