An autonomous sensor for insect flight tracking that captures and stores solar angle-of-incidence without the use of a conventional ADC is presented. The chip uses pairs of Angle-Sensitive Pixels as differential 1-bit ADCs, and an array of these sensors provides a many-bit encoding of angle-of-incidence. Digitization occurs immediately within the pixel by use of a novel in-pixel comparator, thus enabling ultra-low-power, direct-to-digital capture of angle-of-incidence. These measurements are stored in an on-chip memory throughout the flight and can be uploaded to a base station via magnetic backscatter at the end of the flight. To permit full autonomy, the system is powered by on-chip photovoltaics, providing open-circuit voltages in the range of 0.40 − 0.50 V in natural sunlight, the intensity of which can vary throughout a flight. The system consumes a simulated 630nW at nominal supply voltage of 0.45 V, and circuit topologies amenable to photovoltaic power conditions are presented. The chip is envisioned as a flight recorder to be mounted on honey bees to track their trajectories, and bee flights were emulated by carrying the chip along a 226 m outdoor trajectory and downloading the recorded flight data from the chip at a base station in the field. Across 18 trials of the same trajectory, which emulates a small sample of tagged bees visiting known feeding sites and returning to their hive, the average reconstructed final position is 9.6 m away from the true final position, an error less than 5% of the total trajectory length.

中文翻译：

---

自主的，光学供电的，直接到数字的太阳角度记录仪，用于蜜蜂飞行跟踪

提出了一种用于昆虫飞行跟踪的自主传感器，无需使用常规ADC即可捕获和存储太阳入射角。该芯片使用成对的角度敏感像素作为差分1位ADC，这些传感器的阵列提供了入射角的多位编码。通过使用新型的像素内比较器，数字化立即在像素内发生，从而实现了超低功耗，直接数字入射角的捕获。这些测量值在整个飞行过程中都存储在片上存储器中，并且可以在飞行结束时通过磁反向散射上传至基站。为了实现完全自主，该系统由片上光电驱动，在自然阳光下提供0.40-0.50 V范围内的开路电压，其强度会在整个飞行过程中变化。该系统在0.45 V的标称电源电压下消耗了630nW的仿真电流，并提出了适合光伏功率条件的电路拓扑。该芯片可作为飞行记录器安装在蜜蜂上，以追踪蜜蜂的轨迹，并通过沿226 m的室外轨迹携带芯片并在现场基站从芯片下载记录的飞行数据来模拟蜜蜂的飞行。 。在18条相同轨迹的试验中，模拟了一小例带标签的蜜蜂前往已知的觅食地点并返回其蜂巢的过程，平均重建最终位置与真实最终位置相距9.6 m，误差小于总数的5％轨迹长度。该芯片可作为飞行记录器安装在蜜蜂上，以追踪蜜蜂的轨迹，并通过沿226 m的室外轨迹携带芯片并在现场基站从芯片下载记录的飞行数据来模拟蜜蜂的飞行。 。在18条相同轨迹的试验中，模拟了一小例带标签的蜜蜂前往已知的觅食地点并返回其蜂巢的过程，平均重建最终位置与真实最终位置相距9.6 m，误差小于总数的5％轨迹长度。该芯片可作为飞行记录器安装在蜜蜂上，以追踪蜜蜂的轨迹，并通过沿226 m的室外轨迹携带芯片并在现场基站从芯片下载记录的飞行数据来模拟蜜蜂的飞行。 。在18条相同轨迹的试验中，模拟了一小例带标签的蜜蜂前往已知的觅食地点并返回其蜂巢的过程，平均重建最终位置与真实最终位置相距9.6 m，误差小于总数的5％轨迹长度。