An Optimized, Data Distribution Service-Based Solution for Reliable Data Exchange Among Autonomous Underwater Vehicles

Major challenges are presented when managing a large number of heterogeneous vehicles that have to communicate underwater in order to complete a global mission in a cooperative manner. In this kind of application domain, sending data through the environment presents issues that surpass the ones found in other overwater, distributed, cyber-physical systems (i.e., low bandwidth, unreliable transport medium, data representation and hardware high heterogeneity). This manuscript presents a Publish/Subscribe-based semantic middleware solution for unreliable scenarios and vehicle interoperability across cooperative and heterogeneous autonomous vehicles. The middleware relies on different iterations of the Data Distribution Service (DDS) software standard and their combined work between autonomous maritime vehicles and a control entity. It also uses several components with different functionalities deemed as mandatory for a semantic middleware architecture oriented to maritime operations (device and service registration, context awareness, access to the application layer) where other technologies are also interweaved with middleware (wireless communications, acoustic networks). Implementation details and test results, both in a laboratory and a deployment scenario, have been provided as a way to assess the quality of the system and its satisfactory performanceEuropean Commission H2020. SWARMs European project (Smart and Networking Underwater Robots in Cooperation Meshes), under Grant Agreement No. 662107-SWARMs-ECSEL-2014-1, partially supported by the ECSEL JU, the Spanish Ministry of Economy and Competitiveness (Ref: PCIN-2014-022-C02-02)

Aggregate Farming in the Cloud: The AFarCloud ECSEL project

Farming is facing many economic challenges in terms of productivity and cost-effectiveness. Labor shortage partly due to depopulation of rural areas, especially in Europe, is another challenge. Domain specific problems such as accurate monitoring of soil and crop properties and animal health are key factors for minimizing economical risks, and not risking human health. The ECSEL AFarCloud (Aggregate Farming in the Cloud) project will provide a distributed platform for autonomous farming that will allow the integration and cooperation of agriculture Cyber Physical Systems in real-time in order to increase efficiency, productivity, animal health, food quality and reduce farm labor costs. Moreover, such a platform can be integrated with farm management software to support monitoring and decision-making solutions based on big data and real-time data mining techniques.publishedVersio

A distributed architecture for unmanned aerial systems based on publish/subscribe messaging and simultaneous localisation and mapping (SLAM) testbed

A dissertation submitted in fulfilment for the degree of Master of Science. School of Computational and Applied Mathematics, University of the Witwatersrand, Johannesburg, South Africa, November 2017The increased capabilities and lower cost of Micro Aerial Vehicles (MAVs) unveil big opportunities for a rapidly growing number of civilian and commercial applications. Some missions require direct control using a receiver in a point-to-point connection, involving one or very few MAVs. An alternative class of mission is remotely controlled, with the control of the drone automated to a certain extent using mission planning software and autopilot systems. For most emerging missions, there is a need for more autonomous, cooperative control of MAVs, as well as more complex data processing from sensors like cameras and laser scanners. In the last decade, this has given rise to an extensive research from both academia and industry. This research direction applies robotics and computer vision concepts to Unmanned Aerial Systems (UASs). However, UASs are often designed for specific hardware and software, thus providing limited integration, interoperability and re-usability across different missions. In addition, there are numerous open issues related to UAS command, control and communication(C3), and multi-MAVs. We argue and elaborate throughout this dissertation that some of the recent standardbased publish/subscribe communication protocols can solve many of these challenges and meet the non-functional requirements of MAV robotics applications. This dissertation assesses the MQTT, DDS and TCPROS protocols in a distributed architecture of a UAS control system and Ground Control Station software. While TCPROS has been the leading robotics communication transport for ROS applications, MQTT and DDS are lightweight enough to be used for data exchange between distributed systems of aerial robots. Furthermore, MQTT and DDS are based on industry standards to foster communication interoperability of “things”. Both protocols have been extensively presented to address many of today’s needs related to networks based on the internet of things (IoT). For example, MQTT has been used to exchange data with space probes, whereas DDS was employed for aerospace defence and applications of smart cities. We designed and implemented a distributed UAS architecture based on each publish/subscribe protocol TCPROS, MQTT and DDS. The proposed communication systems were tested with a vision-based Simultaneous Localisation and Mapping (SLAM) system involving three Parrot AR Drone2 MAVs. Within the context of this study, MQTT and DDS messaging frameworks serve the purpose of abstracting UAS complexity and heterogeneity. Additionally, these protocols are expected to provide low-latency communication and scale up to meet the requirements of real-time remote sensing applications. The most important contribution of this work is the implementation of a complete distributed communication architecture for multi-MAVs. Furthermore, we assess the viability of this architecture and benchmark the performance of the protocols in relation to an autonomous quadcopter navigation testbed composed of a SLAM algorithm, an extended Kalman filter and a PID controller.XL201

AGNI: an API for the control of automomous service robots

With the continuum growth of Internet connected devices, the scalability of the protocols used for communication between them is facing a new set of challenges. In robotics these communications protocols are an essential element, and must be able to accomplish with the desired communication. In a context of a multi-­‐‑agent platform, the main types of Internet communication protocols used in robotics, mission planning and task allocation problems will be revised. It will be defined how to represent a message and how to cope with their transport between devices in a distributed environment, reviewing all the layers of the messaging process. A review of the ROS platform is also presented with the intent of integrating the already existing communication protocols with the ServRobot, a mobile autonomous robot, and the DVA, a distributed autonomous surveillance system. This is done with the objective of assigning missions to ServRobot in a security context

A middleware protocol for time-critical wireless communication of large data samples

We present a middleware-based protocol that reliably synchronizes large samples consisting of multiple frames efficiently and within application level QoS requirements over a lossy wireless channel. The protocol uses a custom retransmission scheme, exploiting the latency requirements on sample level for frame level scheduling. It can be integrated into the popular DDS middleware. We investigate some technical limits of such a protocol and compare it to existing error protocols in the software stack and in the wireless protocol and combinations thereof. The comparison is based on an Omnet++ simulation using an established wireless channel error model. For evaluation, we take a use case from automated valet parking where infrastructure data provided via a wireless link augments in-vehicle sensor data. The use case respects the related safety requirements. Results show that the application awareness of the presented protocol, significantly improves service availability by transmitting data efficiently in time even under higher frame error rates

The ARCHADE: ubiquitous supercomputing for robotics. Part I: philosophy

In this work, we introduce Ubiquitous Supercomputing for robotics with the objective of opening our imagination to the development of new powerful heterogeneous multi-robot systems able to perform all kind of missions. Supercomputing, also known as High Performance computing (HPC) is the tool that allows us to predict the weather, understand the origins of the universe, create incredibly realistic fantasy movies, send personalized advertisement to millions of users worldwide and much more. Robotics has been mostly absent in its use of HPC but some previous works have lightly flirted with it. With the findings presented in here, we propose a ubiquitous supercomputing ontology, which allows describing systems made up of robots, traditional HPC infrastructures, sensors, actuators and people and exhibiting scalability, user-transparency and ultimately higher computing efficiency. Moreover, we present a technology called The ARCHADE, which facilitates the development, implementation and operation of such systems, and we propose a mechanism to define and automatize missions carried out by ubiquitous supercomputing systems. As a proof of concept, we present a system depicted as Tigers VS Hunters, which illustrates the potential of this technology. The results presented in here are part of a two series work introducing The ARCHADE. This first delivery presents its philosophy and main features. Correspondingly the second part will present a set of use cases and a complete performance benchmark. Supercomputing is part of our lives and it can be found in many research and industrial endeavors. With the ubiquitous supercomputing ontology and The ARCHADE, supercomputing will become part of robotics as well, bringing it therefore everywhere.Peer ReviewedPostprint (published version

Integration of ROS2 with a simulation environment

Dissertação de mestrado integrado em Engenharia InformáticaCurrently, the University of Minho owns a driving simulator, from now on referred to as Driving Simulator Mockup 2-Wheeler (DSM-2W), which mimics a real driving environment for motorcycles. This simulator can reproduce diverse driving scenarios, like driving on different roads, traffic, and weather conditions, and is mostly used to test how the driver reacts to stimulus from subsystems under test in a particular scenario. The simulator has several components, namely, the Mock-up, which represents the motorcycle physically, the software responsible for the simulation environment, that is also projected on a screen, called SILAB [1] as well as several other subsystems and respective software, which all together form a complex distributed system. SILAB creates realistic graphic environments, has different models to control the behavior of other drivers and pedestrians, generates 3D sounds, and facilitates the personalization of the simulation scenario. Robot Operating System 2 (ROS2) [2] provides a set of tools and software libraries that facilitate the develop ment of robot systems and applications. With the increasing reliance on software, sensors, and actuators in the automotive domain, it makes sense to view cars [3] and motorcycles as robots. Therefore, it also makes sense to use ROS2 in the simulation domain to solve the problems at hand. This dissertation describes how ROS2, a well-known and accepted middleware for robotic applications, can also play a role in these contexts acting as a universal interface between motorcycle simulators and external subsystems and thereby significantly improving the system’s expansibility and those subsystems’ portability and reusability.A Universidade do Minho possui um simulador de motas, denominado Driving Simulator Mockup 2-Wheeler (DSM-2W), que imita um ambiente real de condução de motas. Esta ferramenta consegue reproduzir diversos cenários de condução, como conduzir em diferentes condições de estrada, tráfego, bem como em diferentes condições meteorológicas. Esta ferramenta é sobretudo usada para testar como o condutor reage a estímulos de vários sub-sistemas em teste em cenários particulares. O simulador possui diversos componentes, o Mock-up, que representa a mota fisicamente, o software responsável pela projeção do ambiente de simulação no ecrã, chamado SILAB [1], mais um conjunto de sub-sistemas e o respetivo software, que no conjunto formam um complexo sistema distribuído. O SILAB cria ambientes de simulação realistas, tem diferentes modelos para controlar o comportamento dos outros condutores e dos pedestres, gera sons 3D e facilita a personalização do cenário da simulação. O Robot Operating System 2 (ROS2) possui um conjunto de ferramentas e bibliotecas para desenvolver aplicações para robôs [2]. Com o aumento do uso de software, sensores, e atuadores no contexto automóvel, faz sentido equiparar veículos automóveis [3] e motas a robôs Portanto, também faz sentido usar o ROS2 para resolver problemas neste contexto. O objetivo desta dissertação passa por mostrar como o ROS2, um middleware bastante utilizado em aplicações para robôs, pode ter um papel importante em contextos de simulação ao atuar como uma interface universal entre sub-sistemas a testar e um simulador de motas e consequentemente melhorar a extensibilidade do simulador e a portabilidade e reusabilidade desses sub-sistemas

Integration of UAS in Air Traffic and Commercial Space Management

Unmanned Aircraft Systems (UAS) are going to be integrated into the National Airspace (NAS) as well as into the Single European Sky (SESAR). I. e. the European Roadmap describes a step by step approach with a full integration by 2028. Currently space vehicles are also developed to fly remotely piloted in space as well in near orbits or during reentry. Although they will fly without pilot operations on board, they may carry passengers or astronauts, respectively, or they will operate as a fully unmanned freighter to transport supply to the ISS or other space based stations. Currently these flights are operated in segregated airspace during launch and landing. When the number of flights will increase due to the commercialization of space transport, the use of restricted airspace will be no more feasible. To manage segregated airspace is costly and it is affecting the capacity of the air transport system. As the concepts and technology for air traffic insertion of UAS currently exist to a quite matured level, they should be also applied to space vehicles. A concept will be proposed which considers not to fully apply all rules for manned aircraft but to create a system for integration according to achieve an equivalent level of safety for unmanned aircraft and spacecraft