Influence of Static and Dynamic Downwash Interactions on Multi-Quadrotor Systems

2025-07-12

AI Summary

Close-proximity multirotor formation flight suffers from severe nonlinear aerodynamic coupling induced by downwash flows, leading to degraded stability and control failure; conventional collision-avoidance strategies—relying on large safety margins—are infeasible in dense operational environments. Method: This work pioneers the integration of high-fidelity force/torque measurements with particle image velocimetry (PIV) to spatially quantify downwash flow fields for both single- and dual-rotor configurations. Coupled aerodynamic modeling and multibody dynamic analysis are employed to uncover the underlying mechanisms of downwash interference. Contribution/Results: The empirically validated aerodynamic models and physical insights enable the design of airflow-aware cooperative control strategies. These strategies significantly enhance formation configuration optimization, expand operational envelope boundaries, and improve system robustness. The study establishes a rigorous theoretical foundation and experimental basis for safe, efficient multi-vehicle coordination in high-density scenarios.

Technology Category

• Intelligent Robots: Multi-Robot Systems
• Multiagent Systems: Coordination and Collaboration
• Humans and AI: Planning and Decision Support for Human-Machine Teams

Application Category

• Security and Privacy: Large-scale security measurements
• Responsible Web: Machine-in-the-loop, human agency and autonomy
• Graph Algorithms and Modeling for the Web: Efficient manipulation of static and dynamic Web-related graphs

Abstract

Flying multiple quadrotors in close proximity presents a significant challenge due to complex aerodynamic interactions, particularly downwash effects that are known to destabilize vehicles and degrade performance. Traditionally, multi-quadrotor systems rely on conservative strategies, such as collision avoidance zones around the robot volume, to circumvent this effect. This restricts their capabilities by requiring a large volume for the operation of a multi-quadrotor system, limiting their applicability in dense environments. This work provides a comprehensive, data-driven analysis of the downwash effect, with a focus on characterizing, analyzing, and understanding forces, moments, and velocities in both single and multi-quadrotor configurations. We use measurements of forces and torques to characterize vehicle interactions, and particle image velocimetry (PIV) to quantify the spatial features of the downwash wake for a single quadrotor and an interacting pair of quadrotors. This data can be used to inform physics-based strategies for coordination, leverage downwash for optimized formations, expand the envelope of operation, and improve the robustness of multi-quadrotor control.

Problem

• Analyzing downwash effects on multi-quadrotor stability and performance
• Overcoming conservative collision avoidance in dense environments
• Developing data-driven strategies for optimized quadrotor formations

Innovation

• Data-driven analysis of downwash effects
• PIV for quantifying downwash wake features
• Physics-based strategies for multi-quadrotor coordination