多传感器作物表型时间同步采集方法

Multi-sensor Crop Phenotype Time Synchronous Acquisition Method

摘要:

在作物多源信息同步采集方面，集成多源传感器实现作物表型信息的同步采集，已成为当前作物表型获取的趋势。本文针对非结构化环境下动态同步采集关键难题，为精确同步地捕捉作物在特定时刻的多维表型特征数据，设计基于深度相机、双目相机、热红外相机、多光谱相机的固定式多表型性状的成像单元装置，开展基于精准时间协议（Precision time protocol, PTP）下传感器数据的时间同步采集研究，突破多源异构传感器时间同步并行采集技术，实现非结构化环境作物表型多维成像特征的时间同步采集。针对系统的时间同步性和稳定性，进行了连续72 h的测试，各传感器所属的授时板系统时钟（从时钟）与授时板1-PTP时钟（主时钟）之间的时间同步误差均方根均在132 ns以内，长期抖动均在286 ns以内。这一结果表明，时间同步误差符合技术指标要求；对农作物进行高强度的连续采样，进行了100次试验以评估系统的稳定性和可靠性，结果表明系统在整个试验过程中表现出良好的稳定性能，能够稳定地完成连续采集任务；在时间同步的条件下，各传感器通过授时板实现同步触发，采集时间误差控制在1 ms以内。该系统在稳定性和动态性能方面均符合农业生产的实际使用需求。

Abstract:

In the synchronous acquisition of crop multi-source information, integrating multi-source sensors to realize the synchronous acquisition of crop phenotype information has become the current trend of crop phenotype acquisition. Aiming at the key problem of dynamic synchronous acquisition in unstructured environment, in order to accurately and synchronously capture the multidimensional phenotypic feature data of crops at a specific time, a fixed multi-phenotypic trait imaging unit device was designed based on depth camera, binocular camera, thermal infrared camera and multispectral camera. The research on time synchronization acquisition of sensor data was carried out based on precision time protocol (PTP), broke through the time synchronization parallel acquisition technology of multi-source heterogeneous sensors, and realized the time synchronization acquisition of multi-dimensional imaging characteristics of crop phenotypes in unstructured environment. For the time synchronization and stability of the system, a continuous 72 h test was carried out. The root mean square error of time synchronization error between the system clock of the timing board of each sensor (slave clock) and the 1-PTP clock of the timing board (master clock) was less than 132 ns, and the long term jitter was less than 286 ns. This result showed that the time synchronization error met the technical requirements. In order to evaluate the stability and reliability of the system, totally 100 experiments were carried out on crops with high intensity continuous sampling. The results showed that the system showed good stable performance in the whole experiment process, and can stably complete the continuous acquisition task. Under the condition of time synchronization, each sensor was synchronously triggered by the timing board, and the acquisition time error was controlled within 1 ms. The stability and dynamic performance of the system met the actual needs of agricultural production.