Low-cost embedded system for relative localization in robotic swarms

In this paper, we present a small, light-weight, low-cost, fast and reliable system designed to satisfy requirements of relative localization within a swarm of micro aerial vehicles. The core of the proposed solution is based on off-the-shelf components consisting of the Caspa camera module and Gumstix Overo board accompanied by a developed efficient image processing method for detecting black and white circular patterns. Although the idea of the roundel recognition is simple, the developed system exhibits reliable and fast estimation of the relative position of the pattern up to 30 fps using the full resolution of the Caspa camera. Thus, the system is suited to meet requirements for a vision based stabilization of the robotic swarm. The intent of this paper is to present the developed system as an enabling technology for various robotic tasks

Navigation, localization and stabilization of formations of unmanned aerial and ground vehicles

A leader-follower formation driving algorithm developed for control of heterogeneous groups of unmanned micro aerial and ground vehicles stabilized under a top-view relative localization is presented in this paper. The core of the proposed method lies in a novel avoidance function, in which the entire 3D formation is represented by a convex hull projected along a desired path to be followed by the group. Such a representation of the formation provides non-collision trajectories of the robots and respects requirements of the direct visibility between the team members in environment with static as well as dynamic obstacles, which is crucial for the top-view localization. The algorithm is suited for utilization of a simple yet stable visual based navigation of the group (referred to as GeNav), which together with the on-board relative localization enables deployment of large teams of micro-scale robots in environments without any available global localization system. We formulate a novel Model Predictive Control (MPC) based concept that enables to respond to the changing environment and that provides a robust solution with team members' failure tolerance included. The performance of the proposed method is verified by numerical and hardware experiments inspired by reconnaissance and surveillance missions

Cooperative μUAV-UGV autonomous indoor surveillance

In this paper, we present a heterogenous UGV-UAV system cooperatively solving tasks of periodical surveillance in indoor environments. In the proposed scenario, the UGV is equipped with an interactive helipad and it acts as a carrier of the UAV. The UAV is a light-weight quadro-rotor helicopter equipped with two cameras, which are used to inspect locations inaccessible for the UGV. The paper is focused on the most crucial aspects of the proposed UAV-UGV periodical surveillance that are visual navigation, localization and autonomous landing that need to be done periodically. We propose two concepts of mobile helipads employed for correction of imprecise landing of the UAV. Beside the description of the visual navigation, relative localization and both helipads, a study of landing performance is provided. The performance of the complex system is proven by an experiment of autonomous periodical surveillance in a changing environment with presence of people

Multi-vehicle Dynamic Water Surface Monitoring

Repeated exploration of a water surface to detect objects of interest and their subsequent monitoring is important in search-and-rescue or ocean clean-up operations. Since the location of any detected object is dynamic, we propose to address the combined surface exploration and monitoring of the detected objects by modeling spatio-temporal reward states and coordinating a team of vehicles to collect the rewards. The model characterizes the dynamics of the water surface and enables the planner to predict future system states. The state reward value relevant to the particular water surface cell increases over time and is nullified by being in a sensor range of a vehicle. Thus, the proposed multi-vehicle planning approach is to minimize the collective value of the dynamic model reward states. The purpose is to address vehicles' motion constraints by using model predictive control on receding horizon, thus fully exploiting the utilized vehicles' motion capabilities. Based on the evaluation results, the approach indicates improvement in a solution to the kinematic orienteering problem and the team orienteering problem in the monitoring task compared to the existing solutions. The proposed approach has been experimentally verified, supporting its feasibility in real-world monitoring tasks

Communications-Aware Robotics: Challenges and Opportunities

The use of Unmanned Ground Vehicles (UGVs) and Unmanned Aerial Vehicles (UAVs) has seen significant growth in the research community, industry, and society. Many of these agents are equipped with communication systems that are essential for completing certain tasks successfully. This has led to the emergence of a new interdisciplinary field at the intersection of robotics and communications, which has been further driven by the integration of UAVs into 5G and 6G communication networks. However, one of the main challenges in this research area is how many researchers tend to oversimplify either the robotics or the communications aspects, hindering the full potential of this new interdisciplinary field. In this paper, we present some of the necessary modeling tools for addressing these problems from both a robotics and communications perspective, using the UAV communications relay as an example.Comment: 6 pages, 4 figures, accepted for presentation to the 2023 International Conference on Unmanned Aircraft Systems (ICUAS) at Lazarski University, Warsaw, Polan

Kinetic of biogas production from oil palm empty fruit bunches

The production process of oil from Elaeis guineensis palm produces an organic residual. Oil palm empty fruit bunches (OPEFB) are one of the main waste products, representing 7%. Up to now, OPEFB aren't totally used, being an environmental problem. In this paper, the employment of OPEFB pretreated with NaOH is studied as a raw material for biogas production. The pretreatment time (PT) of the OPEFB influences directly on biogas production achieving conversions of volatile solids to biogas of 96% for PT=60 min and 29 days of reaction. Biogas production is adjusted to a first order kinetic law, with kinetic constants for the generation of CH4 (0,108 d-1) and CO2 (0,107 d-1) at the reactor operating temperature (55°C). Finally, a general model is obtained to estimate volatile solids conversion to biogas as a function of pretreatment time and of the residence time inside the reactor