Quadrotors have gained popularity over the last decade, aiding humans in complex tasks such as search and rescue, mapping and exploration. Despite their mechanical simplicity and versatility compared to other types of aerial vehicles, they remain vulnerable to rotor failures. In this paper, we propose an algorithmic and mechanical approach to addressing the quadrotor fault-tolerant problem in case of rotor failures. First, we present a fault-tolerant detection and control scheme that includes various attitude error metrics. The scheme transitions to a fault-tolerant control mode by surrendering the yaw control. Subsequently, to ensure compatibility with platform sensing constraints, we investigate the relationship between variations in robot rotational drag, achieved through a modular mechanical design appendage, resulting in yaw rates within sensor limits. This analysis offers a platform-agnostic framework for designing more reliable and robust quadrotors in the event of rotor failures. Extensive experimental results validate the proposed approach providing insights into successfully designing a cost-effective quadrotor capable of fault-tolerant control. The overall design enhances safety in scenarios of faulty rotors, without the need for additional sensors or computational resources.

翻译：四旋翼飞行器在过去十年中日益普及，协助人类完成搜索救援、测绘与探索等复杂任务。尽管与其他类型飞行器相比具有机械结构简单、多用途等优势，但旋翼故障仍使其面临脆弱性挑战。本文针对旋翼故障场景，提出一种融合算法与机械设计的四旋翼容错方案。首先，我们设计了一种包含多种姿态误差指标的容错检测与控制架构，该方案通过放弃偏航控制权切换至容错控制模式。随后，为确保与平台传感约束的兼容性，通过模块化机械设计附件改变飞行器旋转阻力特性，使偏航角速率保持在传感器限值范围内。该分析为设计旋翼故障时更具可靠性和鲁棒性的四旋翼飞行器提供了平台无关性框架。大量实验验证了所提方法的有效性，为成功设计低成本容错控制四旋翼飞行器提供了实践指导。整体设计无需额外传感器或计算资源，即可提升旋翼故障场景下的安全性。