Early detection and tracking of ejecta in the vicinity of small solar system bodies is crucial to guarantee spacecraft safety and support scientific observation. During the visit of active asteroid Bennu, the OSIRIS-REx spacecraft relied on the analysis of images captured by onboard navigation cameras to detect particle ejection events, which ultimately became one of the mission's scientific highlights. To increase the scientific return of similar time-constrained missions, this work proposes an event-based solution that is dedicated to the detection and tracking of centimetre-sized particles. Unlike a standard frame-based camera, the pixels of an event-based camera independently trigger events indicating whether the scene brightness has increased or decreased at that time and location in the sensor plane. As a result of the sparse and asynchronous spatiotemporal output, event cameras combine very high dynamic range and temporal resolution with low-power consumption, which could complement existing onboard imaging techniques. This paper motivates the use of a scientific event camera by reconstructing the particle ejection episodes reported by the OSIRIS-REx mission in a photorealistic scene generator and in turn, simulating event-based observations. The resulting streams of spatiotemporal data support future work on event-based multi-object tracking.

翻译：在太阳系小天体附近，早期探测和跟踪喷出物对于确保航天器安全和支持科学观测至关重要。在访问活跃小行星贝努期间，OSIRIS-REx航天器依赖分析星载导航相机捕获的图像来探测粒子喷射事件，这最终成为该任务的科学亮点之一。为提升类似时间受限任务的科学回报，本文提出了一种专用于探测和跟踪厘米级粒子的基于事件的解决方案。不同于传统帧式相机，事件相机的像素可独立触发事件，指示传感器平面内该位置和时间的场景亮度是增加还是减少。由于产生稀疏且异步的时空输出，事件相机兼具极高动态范围和时域分辨率与低功耗特性，可对现有星载成像技术形成补充。本文通过利用逼真场景生成器重构OSIRIS-REx任务报告的粒子喷射事件，进而模拟基于事件的观测，论证了科学事件相机的应用价值。由此产生的时空数据流将为未来基于事件的多目标跟踪研究提供支撑。