Event cameras are a promising candidate to enable high speed vision-based control due to their low sensor latency and high temporal resolution. However, purely eventbased feedback has yet to be used in the control of drones. In this work, a first step towards implementing low-latency high-bandwidth control of quadrotors using event cameras is taken. In particular, this paper addresses the problem of one-dimensional attitude tracking using a dualcopter platform equipped with an event camera. The event-based state estimation consists of a modified Hough transform algorithm combined with a Kalman filter that outputs the roll angle and angular velocity of the dualcopter relative to a horizon marked by a black-and-white disk. The estimated state is processed by a proportional-derivative attitude control law that computes the rotor thrusts required to track the desired attitude. The proposed attitude tracking scheme shows promising results of event-camera-driven closed loop control: the state estimator performs with an update rate of 1 kHz and a latency determined to be 13.8 ms, enabling attitude tracking at speeds of over 1600 • /s. A video showing the closed-loop performance of the system is available at https://youtu.be/3nIznSMCMtc
Then, Dimitrova et al. showed low-latency control of quadrotors using event camera, enabling attitude tracking at speeds of over 1600 • /s REF .
Towards Low-Latency High-Bandwidth Control of Quadrotors using Event Cameras
IEEE International Conference on Robotics and Automation (ICRA), Paris, 2020
Engineering Computer Science