Design and Control of SQUEEZE: A Spring-augmented QUadrotor for intEractions with the Environment to squeeZE-and-fly

TL;DR

This paper introduces SQUEEZE, a novel spring-augmented quadrotor capable of physically interacting with environments to navigate through narrow gaps, with a new dynamic model and adaptive control strategies validated through flight tests.

Contribution

The paper presents the design, dynamic modeling, and adaptive control of a passive morphing quadrotor with passive spring-based arms for environment interaction.

Findings

Successfully navigates through narrow gaps and passageways.

Demonstrates stable trajectory tracking with adaptive control.

Validates design through real flight experiments.

Abstract

This paper presents the design and control of a novel quadrotor with a variable geometry to physically interact with cluttered environments and fly through narrow gaps and passageways. This compliant quadrotor with passive morphing capabilities is designed using torsional springs at every arm hinge to allow for rotation driven by external forces. We derive the dynamic model of this variable geometry quadrotor (SQUEEZE), and develop an adaptive controller for trajectory tracking. The corresponding Lyapunov stability proof of attitude tracking is also presented. Further, an admittance controller is designed to account for changes in yaw due to physical interactions with the environment. Finally, the proposed design is validated in flight tests with two setups: a small gap and a passageway. The experimental results demonstrate the unique capability of the SQUEEZE in navigating through constrained narrow spaces.