用于增强现实手术导航系统的光学-惯性混合跟踪方法

摘要

This paper proposes an optical-inertial hybrid tracking method to solve the occlusion problem in opti-cal tracking, in which the optical tracking is used to compensate the bias in inertial sensors when there is no oc-clusion and an FIR filter is used to compensate for the noises of the inertial sensors. The orientation of the target is calculated in a Kalman filter, the position of visible marker points and orientation from inertial tracking unit are fused for calculating the 6 degree-of-freedom motion of targets. Experimental result shows that the proposed sys-tem can track the targets with or without occlusion and display the surgical navigation image coordinated to the targets to the users.%针对手术导航系统中光学跟踪容易受到遮挡影响的问题，提出一种将光学和惯性跟踪信息进行融合的方法。该方法利用有较高精度的光学跟踪系统对惯性传感器的偏置误差进行估算，使用 FIR 滤波器对惯性传感器测量噪声进行滤波，该方法通过 Kalman 滤波器完成数据融合得到目标姿态。当出现部分光学遮挡时，混合跟踪系统将未被遮挡的标志点位置信息与目标的姿态信息进行融合得到完整的6自由度位姿信息。实验结果表明，通过融合光学和惯性跟踪信息，能够在部分遮挡条件下得到准确的位置和姿态信息，并将虚实融合手术导航图像准确地反馈给用户。