Task Space Consensus of Heterogeneous Robots With Time-Delays and Without Velocity Measurements
Carlos I. Aldana, Luis Tabarez, Emmanuel Nuño, Emmanuel Cruz‐Zavala · IEEE Control Systems Letters · 2020
This letter proposes a novel distributed control scheme for heterogeneous robot networks (kinematically and dynamically different), modeled as Euler-Lagrange systems, that solves the leaderless consensus problem in the Special Euclidean space of dimension three (SE(3)). The controller does not rely on velocity measurements and it is robust to variable time-delays in the communication channels. The solution employs a simple Proportional plus damping scheme that, since velocities are not available, injects damping through a dynamical controller. Using Barbalat's Lemma, it is proved that velocities and pose (position and orientation) errors converge asymptotically to zero. A singularity-free representation, unit-quaternions, is used to describe the robots orientations and the network is modeled as an undirected and connected interconnection graph. Simulation results, with an heterogeneous robot network composed of five agents, are presented to illustrate the performance of the proposed control scheme.