Optical tracking systems (OTS) can provide high position accuracy over a large workspace. However, the orientation from the OTS is related to the distance between markers, which contains large errors when the distance is small or line-of-sight problems occur. The orientation estimation with a gyroscope is complementary to the OTS-based orientation. In this article, an error-state Kalman filter (ESKF) is proposed to fuse them. Two experiments were performed to verify the performance: first, a unit including markers and a gyroscope was placed statically and rotated dynamically in 3-D space. Secondly, two units were used to estimate the relative orientation between the hand and fingers. The static and dynamic orientation errors reduced from 0.39° ± 0.16° and 2.75° ± 1.56° to 0.23° ± 0.02° and 1.50° ± 0.62°, respectively, when the distance between markers was 13 mm. The second experimental results show that the fused method improved the OTS performance by smoothing the estimate, filling the relative orientation during the line of sight period, and correcting the estimation when there were identification problems of markers.

中文翻译：

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通过融合陀螺仪信息改进基于光学跟踪的方向估计


光学跟踪系统 (OTS) 可以在大工作空间内提供高定位精度。然而，OTS的定向与标记之间的距离有关，当距离较小或出现视线问题时，其误差较大。使用陀螺仪进行的方向估计是对基于 OTS 的方向的补充。在本文中，提出了一种错误状态卡尔曼滤波器（ESKF）来融合它们。进行了两个实验来验证性能：首先，将包含标记和陀螺仪的单元静态放置并在 3D 空间中动态旋转。其次，使用两个单位来估计手和手指之间的相对方向。当标记之间的距离为13 mm时，静态和动态方向误差分别从0.39°±0.16°和2.75°±1.56°减少到0.23°±0.02°和1.50°±0.62°。第二个实验结果表明，融合方法通过平滑估计、填充视线期间的相对方向以及在存在标记识别问题时校正估计来提高OTS性能。