On contraction analysis for non-linear systems
Automatica (Journal of IFAC)
A Framework for Simulation and Testing of UAVs in Cooperative Scenarios
Journal of Intelligent and Robotic Systems
From Simulated to Real Scenarios: A Framework for Multi-UAVs
SIMPAR '08 Proceedings of the 1st International Conference on Simulation, Modeling, and Programming for Autonomous Robots
Pushing the envelope: a novel hybrid vehicle design and real-time control concept
CA '07 Proceedings of the Ninth IASTED International Conference on Control and Applications
Two-stage energy-optimal formation reconfiguration strategy
Automatica (Journal of IFAC)
A Finite-State Machine for Collaborative Airlift with a Formation of Unmanned Air Vehicles
Journal of Intelligent and Robotic Systems
| Hi-index | 22.15 |
A group of identical unicycles is controlled by means of local feedback laws that require measurements of the unicycles relative positions and speeds. Vehicle interconnections are considered unilateral and are modeled by means of a directed acyclic graph. Although not needed for the implementation of the controllers, the desired trajectory of each vehicle is derived from the requirement that the formation must rotate with the leader while ensuring that the relative positions and line-of-sight angles between unicycles are time-invariant. Exponential convergence of the actual trajectories to a ball centered on the desired trajectories is obtained by computing the Jacobian of the nonlinear dynamics and using results from contraction theory. Instrumental to this derivation is the subsystem feedback decomposition interpretation of the plant model. In this context, convergence depends on the uniform negative definiteness and strict positive realness of the forward and feedback subsystems. Such properties are obtained provided a set of linear and bilinear matrix inequalities as well as kinematic constraints are satisfied. A numerical example illustrates the convergence property of a leader-follower formation.