Circular formation control of fixed-wing UAVs with constant speeds

In this paper we propose an algorithm for stabilizing circular formations of fixed-wing UAVs with constant speeds. The algorithm is based on the idea of tracking circles with different radii in order to control the inter-vehicle phases with respect to a target circumference. We prove that the desired equilibrium is exponentially stable and thanks to the guidance vector field that guides the vehicles, the algorithm can be extended to other closed trajectories. One of the main advantages of this approach is that the algorithm guarantees the confinement of the team in a specific area, even when communications or sensing among vehicles are lost. We show the effectiveness of the algorithm with an actual formation flight of three aircraft. The algorithm is ready to use for the general public in the open-source Paparazzi autopilot.Comment: 6 pages, submitted to IROS 201

A distributed optimization framework for localization and formation control: applications to vision-based measurements

Multiagent systems have been a major area of research for the last 15 years. This interest has been motivated by tasks that can be executed more rapidly in a collaborative manner or that are nearly impossible to carry out otherwise. To be effective, the agents need to have the notion of a common goal shared by the entire network (for instance, a desired formation) and individual control laws to realize the goal. The common goal is typically centralized, in the sense that it involves the state of all the agents at the same time. On the other hand, it is often desirable to have individual control laws that are distributed, in the sense that the desired action of an agent depends only on the measurements and states available at the node and at a small number of neighbors. This is an attractive quality because it implies an overall system that is modular and intrinsically more robust to communication delays and node failures

Circle formation algorithm for autonomous agents with local sensing

Research on cooperative robotics has increased radically over the past decade due to its simplicity and applicability in a variety of fields. Shape formation plays an important role in such cooperative behavior. Our work deals with the formation of a circle by a group of mobile agents (robots) that initially are randomly spread and randomly oriented in an unmapped terrain. The agents have simple characteristics and limited capabilities. They are autonomous, homogeneous, anonymous, and memory-less. They do not communicate with each other, but are able to measure the inter-agent distances and angels. The agents follow the same distributed algorithm synchronously without any central control. The existing algorithms make it necessary to scan all the agents over the whole terrain. The main advantage of our algorithm is that each agent makes use of local information collected from two neighboring partners. Our algorithm also results in a regularly distributed circle for any form of initial distribution. By changing a parameter in the algorithm, the circle can either be made to grow or shrink uniformly. Applications of this work can be made to a variety of areas such as space missions, military operations, in agriculture and fire fighting

Dynamic Circular Formation Of Multi-Agent Systems With Obstacle Avoidance And Size Scaling:A Flocking Approach

Formation control with the flocking approach is an exciting method that can reach the formation without determining the agent's position. This paper focuses on circle formation around the leader or target with geometric properties for the second-order-agent system. This means that the polygon formation is formed with any initial conditions. To create the circular formation, two potential function terms have been used between agent-agent and agent-leader. In our approach, if some fault occurs during the circular formation and some agents fail, the regular polygon formation will still form with fewer agents. Obstacle avoidance for a single-circle formation and collision-free motion is guaranteed. A circular formation with size scaling is proposed to better pass through obstacles. Also, several circles with the desired radius can be reached with changes in the agent-leader potential function. In this work, optimization algorithms with different scenarios compare to obtain the parameters of our algorithm

GUARDIANS final report

Emergencies in industrial warehouses are a major concern for firefghters. The large dimensions together with the development of dense smoke that drastically reduces visibility, represent major challenges. The Guardians robot swarm is designed to assist fire fighters in searching a large warehouse. In this report we discuss the technology developed for a swarm of robots searching and assisting fire fighters. We explain the swarming algorithms which provide the functionality by which the robots react to and follow humans while no communication is required. Next we discuss the wireless communication system, which is a so-called mobile ad-hoc network. The communication network provides also one of the means to locate the robots and humans. Thus the robot swarm is able to locate itself and provide guidance information to the humans. Together with the re ghters we explored how the robot swarm should feed information back to the human fire fighter. We have designed and experimented with interfaces for presenting swarm based information to human beings