Tethered Power for a Series of Quadcopters: Analysis and Applications

TL;DR

This paper analyzes the power requirements and efficiency of tethered quadcopters arranged in series, providing insights into design constraints, power optimization, and practical applications like firefighting and obstacle navigation.

Contribution

It introduces a comprehensive analysis of power distribution in multi-quadcopter tethered systems, highlighting electrical limitations and demonstrating efficiency gains with multiple quadcopters.

Findings

Two-quadcopter systems consume less power than single-quadcopter systems at large distances.

A two-quadcopter system can save up to 26% power in firefighting scenarios.

Experimental validation shows effective operation in cluttered environments.

Abstract

Tethered quadcopters are used for extended flight operations where the power to the system is provided via a tether connected to an external power source. In this work, we consider a system of multiple quadcopters powered by a single tether. We study the design factors that influence the power requirements, such as the electrical resistance of the tether, input voltage, and quadcopters' positions. We present an analysis to predict the required power to be supplied to a series of N tethered quadcopters, with respect to the thrust of each quadcopter which guarantees electrical safety and helps in design optimization. We find that there is a critical boundary of thrusts that cannot be exceeded due to fundamental electrical limitations. We compare the power consumption for one tethered quadcopter and two tethered quadcopters and show that for large quadcopters far enough from the anchor point, a two-quadcopter system consumes lesser power. We show that, for a representative use case of firefighting, a tethered system with two quadcopters consumes 26% less power than a corresponding system with one quadcopter. Finally, we present experiments demonstrating the use of a two-quadcopter tethered system as compared to a one-quadcopter tethered system in a cluttered environment, such as passing through a window and grasping an object over an obstacle.