Gimballed Rotor Mechanism for Omnidirectional Quadrotors

2025-11-19

AI Summary

Conventional quadrotors are underactuated and thus incapable of full six-degree-of-freedom (6-DOF) omnidirectional motion. Existing omnidirectional designs typically rely on structural reconfiguration, compromising modularity and scalability. This paper proposes a modular gimbaled rotor mechanism: miniature servo actuators are integrated into standard rotor modules, enabling independent tilt control of each propeller without modifying the main airframe—thereby achieving full actuation. A custom control allocation algorithm, implemented atop the PX4 autopilot platform, decouples attitude and thrust regulation to ensure independent yet coordinated 6-DOF maneuvering. The system is lightweight (mass increase <35 g per rotor) and highly extensible. Experimental validation demonstrates stable and precise performance across diverse maneuvers—including hover, lateral translation, inverted flight, and arbitrary-axis rotation—significantly extending the operational envelope of conventional quadrotors.

Technology Category

• Intelligent Robots: Multimodal Perception & Sensor Fusion
• Application Domains: Mobility, Driving & Flight
• Computer Vision: Multi-modal Vision

Application Category

• Systems and Infrastructure for Web, Mobile and WoT: Experiences and lessons learnt from Web-based algorithms and system deployments
• Responsible Web: Machine-in-the-loop, human agency and autonomy
• User Modeling, Personalization and Recommendation: On-Device user modeling, personalization, and recommendation

Abstract

This paper presents the design of a gimballed rotor mechanism as a modular and efficient solution for constructing omnidirectional quadrotors. Unlike conventional quadrotors, which are underactuated, this class of quadrotors achieves full actuation, enabling independent motion in all six degrees of freedom. While existing omnidirectional quadrotor designs often require significant structural modifications, the proposed gimballed rotor system maintains a lightweight and easy-to-integrate design by incorporating servo motors within the rotor platforms, allowing independent tilting of each rotor without major alterations to the central structure of a quadrotor. To accommodate this unconventional design, we develop a new control allocation scheme in PX4 Autopilot and present successful flight tests, validating the effectiveness of the proposed approach.

Problem

• Designing a gimballed rotor mechanism for omnidirectional quadrotors
• Achieving full actuation and independent motion in six degrees
• Developing control allocation for lightweight modular rotor system

Innovation

• Gimballed rotor mechanism for omnidirectional quadrotors
• Independent rotor tilting via integrated servo motors
• New control allocation scheme in PX4 Autopilot