Multi-vehicle Control and Autonomy for Swarming Quadrotors
Charles Flanagan · AIAA Scitech 2021 Forum · 2021
Multi-vehicle swarms have many applications that include searching, target tracking, and mapping unfamiliar environments. Much of the research on quadrotor swarms has focused on its use for military, communication, industrial and farming applications. Recently, other uses have been developed that make use of a swarm’s ability to achieve complex in-air formations. In 2017, IBM demonstrated the use of swarming drones at the Superbowl halftime show, demonstrating the use of the technology as a replacement for fireworks in large-scale visual demonstrations. Autonomous swarms, particularly when used in real-world scenarios, require robust control systems to ensure that the vehicles behave as expected, crashes are avoided, and the mission is achieved. Some quadrotor swarms are guided by a series of waypoints provided by a ground station. This connect-the-dots style of control is limited in its ability to achieve complex formations using closed loop control. This paper looks at extending the capability of multi-vehicle swarms by using kinematic information in feedback control. This research builds upon the existing quadrotor swarm testbed developed at the University of Maryland’s Collective Dynamics and Control Lab and introduces two new capabilities: kinematic commands and visual feedback with onboard LEDs. Kinematic control allows more advanced control schemes to be implemented which use vehicle position, velocity, and acceleration information for closed-loop control. This expands the possibilities for things like collision avoidance and complex formations. A visual feedback system with LEDs mounted on each quadrotor allows the swarm to more easily communicate with the swarm operators and makes for a more engaging visual display for audiences. LEDs were used in this research to visualize vehicle status, identify errors, and changed color dynamically to indicate proximity to other vehicles, heading, velocity and more. Experiments were performed at the University of Maryland’s Fearless Flight Facility, a large, netted outdoor field. Two types of custom-built quadrotors – one 12 inch and one 5 inch – were flown together in formations. The formations and controllers used in these experiments were first developed through simulation, including software-in-the-loop simulation. Results will show comparisons between ideal, simulated formations and the experimental data recorded from flight tests.