Department of Communications, Navigation and Control Engineering, National Taiwan Ocean University, 2 Pei-Ning Rd, Keelung 202-24, Taiwan.
Sensors (Basel). 2011;11(8):7437-54. doi: 10.3390/s110807437. Epub 2011 Jul 25.
Accurate estimation of the motion and shape of a moving object is a challenging task due to great variety of noises present from sources such as electronic components and the influence of the external environment, etc. To alleviate the noise, the filtering/estimation approach can be used to reduce it in streaming video to obtain better estimation accuracy in feature points on the moving objects. To deal with the filtering problem in the appropriate nonlinear system, the extended Kalman filter (EKF), which neglects higher-order derivatives in the linearization process, has been very popular. The unscented Kalman filter (UKF), which uses a deterministic sampling approach to capture the mean and covariance estimates with a minimal set of sample points, is able to achieve at least the second order accuracy without Jacobians' computation involved. In this paper, the UKF is applied to the rigid body motion and shape dynamics to estimate feature points on moving objects. The performance evaluation is carried out through the numerical study. The results show that UKF demonstrates substantial improvement in accuracy estimation for implementing the estimation of motion and planar surface parameters of a single camera.
由于电子元件等各种噪声源以及外部环境等因素的影响,准确估计运动物体的运动和形状是一项具有挑战性的任务。为了减轻噪声,可以使用滤波/估计方法来减少流视频中的噪声,以提高运动物体特征点的估计精度。为了处理适当非线性系统中的滤波问题,扩展卡尔曼滤波器(EKF)在线性化过程中忽略了高阶导数,因此非常受欢迎。无迹卡尔曼滤波器(UKF)使用确定性采样方法,用最小数量的样本点来捕获均值和协方差估计值,无需计算雅可比矩阵,即可至少达到二阶精度。在本文中,UKF 被应用于刚体运动和形状动力学,以估计运动物体上的特征点。通过数值研究进行性能评估。结果表明,UKF 在实现单摄像机运动和平面参数的估计方面,在精度估计方面有了显著的提高。