视觉传感器和惯性传感器的时间标定方法  

Time Calibration Method for Vision Sensor and Inertial Sensor

作　　者：付凤杰 李辰懋 吴丽 刘衍青 朱冬晨 李嘉茂 张晓林 Fu Fengjie;Li Chenmao;Wu Li;Liu Yanqing;Zhu Dongchen;Li Jiamao;Zhang Xiaolin(State Key Laboratory of Transducer Technology-Bionic Vision System Laboratory,Shanghai Institute of Microsystem and Information Technology,Chinese Academy of Sciences,Shanghai 200050,China;University of Chinese Academy of Sciences,Beijing 100049,China;School of Information Science and Technology,ShanghaiTech University,Shanghai 201210,Chhia)

机构地区：[1]中国科学院上海微系统与信息技术研究所传感技术联合国家重点实验室-仿生视觉系统实验室,上海200050 [2]中国科学院大学,北京100049 [3]上海科技大学信息科学与技术学院,上海201210

出　　处：《光学学报》2021年第24期193-202,共10页Acta Optica Sinica

基　　金：中国科学院前沿科学重点研究项目(QYZDY-SSW-JSC034);中国科学院青年创新促进会(2018270);上海市“脑与类脑智能基础转化应用研究”市级重大科技专项资助(2018SHZDZX01);张江实验室、上海市青年科技英才扬帆计划(20YF1457000)。

摘　　要：视觉惯性信息融合的同时定位和建图(SLAM)技术是机器人导航领域的热点问题。多模态数据同步是数据融合算法的前提,其关键在于获取不同传感器采集时刻的准确时间戳。视觉传感器的时间戳可通过硬件方法准确获得,而惯性传感器的时间戳通常粗略地用输出时间代替,这必将导致视觉惯性融合算法精度的降低。针对该问题提出了一种视觉惯性传感器的时间同步标定方法。首先设计了一种基于平面单摆的标定装置,视觉传感器与惯性传感器在平面单摆运动中独立捕获数据,并基于同一时钟添加时间标记;其次,提出了基于最小二乘法估计摆锤重心角位移函数和角速度函数的方法;最后,通过比较两个函数的相位差获得惯性传感器的输出延时和时间戳。实验结果表明所提方法的重复标定均方差为0.018 ms,这证明所提方法的有效性。Simultaneous localization and mapping(SLAM) based on visual-inertial information fusion is a hot topic in the field of robot navigation.Multimodal data synchronization is a premise of the data fusion algorithm,and the key to it is to accurately obtain the timestamps of the acquisition time of different sensors.While the timestamp of the vision sensor can be accurately obtained by the hardware method,that of the inertial sensor is usually roughly replaced by the output time,which lowers the accuracy of the visual-inertial fusion algorithm.In this paper,a method of time synchronization calibration of the visual-inertial sensor was proposed.A calibration device based on a planar simple pendulum was designed.The vision sensor and the inertial sensor captured data independently in the motion of the planar simple pendulum,and timestamps were added according to the same clock.Then,a method of estimating the angular displacement function and the angular velocity function of the pendulum’s center of gravity was proposed by the least squares method.Finally,the output delay and timestamp of the inertial sensor were obtained by comparing the phase differences of the two functions.Experimental results show that the standard deviation of repeated calibration by the proposed method is 0.018 ms,which proves the effectiveness of the method.

关 键 词：机器视觉 时间同步标定 单摆标定装置 视觉惯性同步 视觉惯性传感器 数据采集时间戳 

分 类 号：TP391.4[自动化与计算机技术—计算机应用技术]