PID vs LQ control techniques applied to an indoor micro quadrotor

TLDR

Miniature flying robots, enabled by advances in sensing and actuation, are increasingly feasible and useful for small‑area monitoring and building exploration, as exemplified by the OS4 project. The study compares two model‑based control techniques for an autonomous four‑rotor micro helicopter. The authors implemented a PID controller using simplified dynamics and a linear‑quadratic controller based on a detailed model, validating both through simulations and bench tests. The first in‑flight test of the released quadrotor confirmed the effectiveness of both control laws.

Abstract

The development of miniature flying robots has become a reachable dream, thanks to the new sensing and actuating technologies. Micro VTOL systems represent a useful class of flying robots because of their strong abilities for small-area monitoring and building exploration. In this paper, we present the results of two model-based control techniques applied to an autonomous four-rotor micro helicopter called quadrotor. A classical approach (PID) assumed a simplified dynamics and a modern technique (LQ) based on a more complete model. Various simulations were performed and several tests on the bench validate the control laws. Finally, we present the results of the first test in flight with the helicopter released. These developments are part of the OS4 project in our lab.