30 research outputs found
Safe navigation and human-robot interaction in assistant robotic applications
L'abstract è presente nell'allegato / the abstract is in the attachmen
Multi-Robot Patrol Algorithm with Distributed Coordination and Consciousness of the Base Station's Situation Awareness
Multi-robot patrolling is the potential application for robotic systems to
survey wide areas efficiently without human burdens and mistakes. However, such
systems have few examples of real-world applications due to their lack of human
predictability. This paper proposes an algorithm: Local Reactive (LR) for
multi-robot patrolling to satisfy both needs: (i)patrol efficiently and
(ii)provide humans with better situation awareness to enhance system
predictability. Each robot operating according to the proposed algorithm
selects its patrol target from the local areas around the robot's current
location by two requirements: (i)patrol location with greater need, (ii)report
its achievements to the base station. The algorithm is distributed and
coordinates the robots without centralized control by sharing their patrol
achievements and degree of need to report to the base station. The proposed
algorithm performed better than existing algorithms in both patrolling and the
base station's situation awareness.Comment: This work has been submitted to the IEEE for possible publication.
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Robots learn to behave: improving human-robot collaboration in flexible manufacturing applications
L'abstract è presente nell'allegato / the abstract is in the attachmen
Biologically Inspired Connected Advanced Driver Assistance Systems
Advanced Driver Assistance Systems (ADAS) have become commonplace in the automotive industry over the last few decades. Even with the advent of ADAS, however, there are still a significant number of accidents and fatalities. ADAS has in some instances been shown to significantly reduce the number and severity of accidents. Manufacturers are working to avoid ADAS plateauing for effectiveness, which has led the industry to pursue various avenues of investment to ascend the next mountain of challenges – vehicle autonomy, smart mobility, connectivity, and electrification – for reducing accidents and injuries. A number of studies pertaining to ADAS scrutinize a specific ADAS technology for its effectiveness at mitigating accidents and reducing injury severity. A few studies take holistic accounts of ADAS. There are a number of directions ADAS could be further progressed. Industry manufacturers are improving existing ADAS technologies through multiple avenues of technology advancement. A number of ADAS systems have already been improved from passive, alert or warning, systems to active systems which provide early warning and if no action is taken will control the vehicle to avoid a collision or reduce the impact of the collision. Studies about the individual ADAS technologies have found significant improvement for reduction in collisions, but when evaluating the actual vehicles driving the performance of ADAS has been fairly constant since 2015. At the same time, industry is looking at networking vehicle ADAS with fixed infrastructure or with other vehicles’ ADAS. The present literature surrounding connected ADAS be it with fixed systems or other vehicles with ADAS focuses on the why and the how information is passed between vehicles. The ultimate goal of ADAS and connected ADAS is the development of autonomous vehicles.
Biologically inspired systems provide an intriguing avenue for examination by applying self-organization found in biological communities to connecting ADAS among vehicles and fixed systems. Biological systems developed over millions of years to become highly organized and efficient. Biological inspiration has been used with much success in several engineering and science disciplines to optimize processes and designs. Applying movement patterns found in nature to automotive transportation is a rational progression.
This work strategizes how to further the effectiveness of ADAS through the connection of ADAS with supporting assets both fixed systems and other vehicles with ADAS based on biological inspiration. The connection priorities will be refined by the relative positioning of the assets interacting with a particular vehicle’s ADAS. Then based on the relative positioning data distribution among systems will be stratified based on level of relevance. This will reduce the processing time for incorporating the external data into the ADAS actions.
This dissertation contributes to the present understanding of ADAS effectiveness in real-world situations and set forth a method for how to optimally connect local ADAS vehicles following from biological inspiration. Also, there will be a better understanding of how ADAS reduces accidents and injury severity. The method for how to structure an ADAS network will provide a framework for auto-manufacturers for the development of their proprietary networked ADAS. This method will lead to a new horizon for reducing accidents and injury severity through the design of connecting ADAS equipped vehicles.Ph.D
Formation morphing and collision avoidance in swarms of robots
Formation maintenance and collision avoidance are two of the key factors in swarm robotics. The demand for autonomous fleets of robots is ever increasing from manufacturing to product deliveries to surveillance to mapping and so on. Moreover, for resource constrained autonomous robots, such as UAVs and UGVs, energy-efficiency is very vital due to their limited batteries. Therefore formation maintenance and collision avoidance developed for such robots need to be energy-efficient. Integration between these two approaches needs to be performed systematically. The experimental analysis of the proposed approaches presented in this thesis target two main branches: 1) action based and 2) perception based energy consumption in a swarm of robots. In the first branch, there are two different paths: i) optimal formation morphing: the main goal is to the optimize the reformation process from the highest level of agitation of the swarm, i.e., maximum disturbance in the formation shape and ii) congestion minimization: the main goal here is to find an optimal solution for distribution of the swarm into sub-swarms to minimize the delays due to over population of the agents while bypassing the obstacles. In the second branch, i.e., perception based energy consumption, the main goal is to increase the mission life on a single charge by injecting the adaptive consciousness into the agents so they can turn off their ranging sensors and navigate while listening to their leader. For formation collision co-awareness, we systematically integrated the methodologies by designing a multi-priority control and utilized the non-rigid mapping scheme of thin-plate splines technique to minimize the deformation caused by obstacle avoidance. For congestion-aware morphing and avoidance maneuvers, we discuss how the delays caused by over population can be minimized with local sense and avoid approach. The leader, upon detection of obstacles, pre-estimates the optimal configuration, i.e., number of agents in the sub-swarms, and divides the swarm as such. We show the efficiency of the proposed approach experimentally
On the Combination of Game-Theoretic Learning and Multi Model Adaptive Filters
This paper casts coordination of a team of robots within the framework of game theoretic learning algorithms. In particular a novel variant of fictitious play is proposed, by considering multi-model adaptive filters as a method to estimate other players’ strategies. The proposed algorithm can be used as a coordination mechanism between players when they should take decisions under uncertainty. Each player chooses an action after taking into account the actions of the other players and also the uncertainty. Uncertainty can occur either in terms of noisy observations or various types of other players. In addition, in contrast to other game-theoretic and heuristic algorithms for distributed optimisation, it is not necessary to find the optimal parameters a priori. Various parameter values can be used initially as inputs to different models. Therefore, the resulting decisions will be aggregate results of all the parameter values. Simulations are used to test the performance of the proposed methodology against other game-theoretic learning algorithms.</p
Algorithms for multi-robot systems on the cooperative exploration & last-mile delivery problems
La aparición de los vehÃculos aéreos no tripulados (UAVs) y de los vehÃculos terrestres no tripulados (UGVs) ha llevado a la comunidad cientÃfica a enfrentarse a problemas ideando paradigmas de cooperación con UGVs y UAVs. Sin embargo, no suele ser trivial determinar si la cooperación entre UGVs y UAVs es adecuada para un determinado problema. Por esta razón, en esta tesis, investigamos un paradigma particular de cooperación UGV-UAV en dos problemas de la literatura, y proponemos un controlador autónomo para probarlo en escenarios simulados.
Primero, formulamos un problema particular de exploración cooperativa que consiste en alcanzar un conjunto de puntos de destino en un área de exploración a gran escala. Este problema define al UGV como una estación de carga móvil para transportar el UAV a través de diferentes lugares desde donde el UAV puede alcanzar los puntos de destino. Por consiguiente, proponemos el algoritmo TERRA para resolverlo. Este algoritmo se destaca por dividir el problema de exploración en cinco subproblemas, en los que cada subproblema se resuelve en una etapa particular del algoritmo.
Debido a la explosión de la entrega de paquetes en las empresas de comercio electrónico, formulamos también una generalización del conocido problema de la entrega en la última milla. En este caso, el UGV actúa como una estación de carga móvil que transporta a los paquetes y a los UAVs, y estos se encargan de entregarlos. De esta manera, seguimos la estrategia de división descrita por TERRA, y proponemos el algoritmo COURIER. Este algoritmo replica las cuatro primeras etapas de TERRA, pero construye una nueva quinta etapa para producir un plan de tareas que resuelva el problema. Para evaluar el paradigma de cooperación UGV-UAV en escenarios simulados, proponemos el controlador autónomo ARIES. Este controlador sigue un enfoque jerárquico descentralizado de lÃder-seguidor para integrar cualquier paradigma de cooperación de manera distribuida.
Ambos algoritmos han sido caracterizados para identificar los aspectos relevantes del paradigma de cooperación en los problemas relacionados. Además, ambos demuestran un gran rendimiento del paradigma de cooperación en tales problemas, y al igual que el controlador autónomo, revelan un gran potencial para futuras aplicaciones reales.The emergence of Unmanned Aerial Vehicles (UAVs) and Unmanned
Ground Vehicles (UGVs) has conducted the research community to
face historical complex problems by devising UGV-UAV cooperation
paradigms. However, it is usually not a trivial task to determine
whether or not a UGV-UAV cooperation is suitable for a particular
problem. For this reason, in this thesis, we investigate a particular
UGV-UAV cooperation paradigm over two problems in the literature,
and we propose an autonomous controller to test it on simulated
scenarios.
Driven by the planetary exploration, we formulate a particular cooperative
exploration problem consisting of reaching a set of target
points in a large-scale exploration area. This problem defines the UGV
as a moving charging station to carry the UAV through different locations
from where the UAV can reach the target points. Consequently,
we propose the cooperaTive ExploRation Routing Algorithm (TERRA)
to solve it. This algorithm stands out for splitting up the exploration
problem into five sub-problems, in which each sub-problem is solved
in a particular stage of the algorithm. In the same way, driven by the
explosion of parcels delivery in e-commerce companies, we formulate
a generalization of the well-known last-mile delivery problem. This
generalization defines the same UGV’s and UAV’s rol as the exploration
problem. That is, the UGV acts as a moving charging station
which carries the parcels along several UAVs to deliver them. In this
way, we follow the split strategy depicted by TERRA to propose the
COoperative Unmanned deliveRIEs planning algoRithm (COURIER).
This algorithm replicates the first four TERRA’s stages, but it builds a
new fifth stage to produce a task plan solving the problem. In order to
evaluate the UGV-UAV cooperation paradigm on simulated scenarios,
we propose the Autonomous coopeRatIve Execution System (ARIES).
This controller follows a hierarchical decentralized leader-follower approach
to integrate any cooperation paradigm in a distributed manner.
Both algorithms have been characterized to identify the relevant
aspects of the cooperation paradigm in the related problems. Also,
both of them demonstrate a great performance of the cooperation
paradigm in such problems, and as well as the autonomous controller,
reveal a great potential for future real applications