一种改进的视觉罗盘姿态测量方法  

A Modified Visual Compass Attitude Estimation Method

作　　者：徐伟杰[1] 李平[1] 韩波[1] 

机构地区：[1]浙江大学控制科学与工程系,杭州310027

出　　处：《传感技术学报》2011年第12期1728-1733,共6页Chinese Journal of Sensors and Actuators

基　　金：国家973计划项目课题(2009CB320603)

摘　　要：Montiel等人提出的"视觉罗盘"是一种以摄像机为唯一传感器,基于EKF-SLAM的姿态测量方法。在摄像机旋转不平滑时需要提高运动模型中系统噪声的先验方差设定值,但是会导致匹配计算量增大和匹配错误发生率升高。针对上述问题,本文给出一种改进的视觉罗盘姿态测量方法。该方法首先使用多分辨率路标选取策略初始化新路标,然后使用逐层主动搜索匹配算法以减少匹配计算量和降低匹配错误发生率,最后使用最小抽样集为2个匹配点的RANSAC算法去除匹配野点。将改进的视觉罗盘姿态测量方法用于处理室外采集的视频,实验结果表明其具有计算量更小和测量姿态精确的优点。The visual compass proposed by Montiel et al.is an attitude estimation method based on EKF-SLAM that using camera as the only sensor.When camera rotation is unsmooth,a priori system noise covariance in motion model should be set to a large value,but it results in high computational cost for matching and high rate of matching error occurrence.Focusing on those problems,a modified visual compass attitude estimation method is presented.First,a multi-resolution landmark selection strategy is used for new landmark initialization.Then,an active search/match layer by layer algorithm is used to reduce both the computational cost and the rate of error occurrence.Finally,a RANSAC algorithm sampling 2 matched points is used to remove the outliers in matching result.The modified visual compass attitude estimation method is applied to the outdoor video,and the experimental results shows that the modified method has advantage of less computational cost and improved accuracy of attitude estimation.

关 键 词：姿态估计 视觉罗盘 同步定位与地图创建 图像金字塔 随机抽样一致性 

分 类 号：TN911.73[电子电信—通信与信息系统] TP391.41[电子电信—信息与通信工程]