A Passive Velocity Field Control for Navigation of Quadrotors with Model-free Integral Sliding Modes

Velocity field (VF) control has proved effective for kinematic robots, aiming essentially at providing desired velocities for navigation along the field, and for obstacle avoidance in cluttered environments. When robot dynamics are involved, it is usually considered either that dynamics are known and that robot is fully actuated, thus it is not clear how to deal with VF control (VFC) for unknown underactuated dynamics, such as for a quadrotor. Moreover, passive VF (PVF) stands for an attractive methodology for quadrotors because of it yields time-invariant nominal spatial field for smooth approaching and easy manoeuvring. In this paper, we propose a constructive method to design a PVF-based controller with a chattering-free integral sliding modes for local exponential position tracking. The salient feature of our proposal is the passive nature of the field as well as the controller is model-free for the complete standard quasi-Lagrangian dynamic model of the quadrotor. The controller does not require the derivative nor any assumption on boundedness on the integral of the VF, yet the closed-loop withstands robustness against parametric and model uncertainties. Simulations are discussed, and remarks address the viability of the proposed approach.