Collision detection and recovery for aerial robots remain a challenge because of the limited space for sensors and local stability of the flight controller. We introduce a novel collision-resilient quadrotor that features a compliant arm design to enable free flight while allowing for one passive degree of freedom to absorb shocks. We further propose a novel collision detection and characterization method based on Hall sensors, as well as a new recovery control method to generate and track a smooth trajectory after a collision occurs. Experimental results demonstrate that the robot can detect and recover from high-speed collisions with various obstacles such as walls and poles. Moreover, it can survive collisions that are hard to detect with existing methods based on IMU data and contact models, for example, when colliding with unstructured surfaces, or being hit by a moving obstacle while hovering.

翻译：由于传感器空间有限和飞行控制器在当地稳定,对空中机器人的碰撞探测和回收仍是一项挑战。我们引入了新型的具有碰撞抗御力的二次钻探器,配有符合要求的手臂设计,以便能够自由飞行,同时允许有一定程度的被动吸收冲击的自由度。我们进一步提议以霍尔传感器为基础的新的碰撞探测和定性方法,以及一种新的恢复控制方法,以便在碰撞发生后产生和跟踪平稳轨道。实验结果显示,机器人能够用墙壁和杆等各种障碍从高速碰撞中探测和复原。此外,它能够幸存到碰撞,而根据以IMU数据和接触模型为基础的现有方法很难探测,例如,在与无结构的表面碰撞时,或在悬浮时受到移动障碍的撞击。