船舶减纵摇控制的LQG方法研究

提出一种船舶减纵摇控制的新方法.海浪对船舶的扰动力和力矩是一种平稳随机过程,基于切片理论,求得海浪扰动力和力矩的一个样本.一方面通过Kalman滤波对船舶的姿态进行有色估计,然后对系统进行随机最优控制.另一方面利用递推最小二乘法对海浪扰动进行建模.将扰动模型与原来的系统模型合并为新的系统模型,并引入白噪声作为新的系统干扰.对扩展后的新系统,运用线性二次高斯(LQG)设计方法计算出扩展Kalman滤波增益阵和扩展随机最优控制增益阵.结果表明,利用经典的LQG控制方法实现船舶减纵摇控制是可行的.最后,通过对扩展随机最优控制效果和有色随机最优控制效果的对比,可以看出扩展随机最优控制在工程应用中更可取.     

Kalman滤波用于舰船运动姿态估计的研究

讨论了 Kalman 滤波用于舰船横摇运动姿态估计的应用方法与应用效果针对海浪干扰及测量噪声均为有色噪声的情况下,提出了如何使用 Kalman 次优滤波器和最优滤波器进行舰船横摇运动姿态的估计和预报的理论基础与方法.在IBM 计算机上进行了数字仿真,并给出了仿真的统计结果与仿真曲线.结果表明,采用本文研究的方法进行舰船横摇运动姿态的估计,可获得令人满意的结果。     

合成孔径声纳运动估计的鲁棒Kalman滤波方法

针对存在观测野值影响的合成孔径声纳运动测量难题,提出利用M-估计原理进行参数最优估计,使得估计误差在一类Huber函数下最小,而不像Kalman滤波那样,寻求估计误差在二范数下的最小,并构造了鲁棒Kalman滤波算法,用来处理合成孔径声纳姿态、运动估计问题．由于Huber函数对大的估计误差不敏感,可以有效地克服观测野值的影响,同时计算机仿真结果表明,该方法在系统存在野值的情况下,仍能对合成孔径声纳运动参数进行估计．     

利用船舶运动数据估计海浪方向谱的研究

有效的利用海浪方向谱的信息能够为船舶安全航行和动力定位控制提供帮助,传统的海浪谱估计方法使用波浪浮标等不能随船安装的仪器,不能用于作业中的船舶。对动力定位船舶进行定点作业情况下的海浪方向谱估计进行研究,提出一种基于船舶运动响应数据估计当前海浪方向谱的方法,采用多维AR算法估计船舶运动交叉谱,采用遗传算法求解海浪方向谱的最优参数,并对4种海况情况进行了仿真实验,验证了该方法的有效性。     

A new optimal approach to segmentation of 2D range scans to line sections

In order to obtain a compact and exact representation of 2D range scans, UKF (unscented Kalman filter) and CDKF (central difference Kalman filter) were proposed for extracting the breakpoint of the laser data. Line extraction was performed in every continuous breakpoint region by detecting the optimal angle and the optimal distance in polar coordinates, and every breakpoint area was constructed with two points. As a proof to the method, an experiment was performed by a mobile robot equipped with one SICK laser rangefinder, and the results of UKF/CDKF in breakpoint detection and line extraction were compared with those of the EKF (extended Kalman filter). The results show that the exact geometry of the raw laser data of the environments can be obtained by segmented raw measurements (combining the proposed breakpoint detection approach with the line extraction method), and method UKF is the best one compared with CDKF and EKF.     

人体运动单侧优势与科里奥利力

历来研究生命之演化皆忽视地球自转这一非惯性系统所引起的作用,本文举出大量例证旨在说明人体运动单侧优势化是受科里奥利力诱导通过动物自身的反馈作用而形成的.     

一种U—D分解自适应推广卡尔曼滤波及应用

为了改善自适应卡尔曼滤波的数值稳定性和计算效率,防止滤波发散,本文在自适应推广卡尔曼滤波的基础上,利用U-D分解滤波,提出一种U-D分解自适应推广卡尔曼滤波新算法,并把该算法应用于飞行状态估计问題,仿真及实际飞行数据计算结果证明了本文方法的有效性.     

水下机器人动力定位中的海流及不平衡力估计

提出了一种基于Ｋａｌｍａｎ滤波的海流、不平衡力估计方法；同时应用了机理建模和神经网络建模的混合建模方法，用神经网络修正运动模型，有效地保证了滤波估计的准确性。并给出了仿真实验结果。     

Mechanics model of additional longitudinal force transmission between bridges and continuously welded rails with small resistance fasteners

A new mechanics model, which reveals additional longitudinal force transmission between the continuously welded rails and the bridges, is established on the fact that the influence of the mutual relative displacement among the rail, the sleeper and the beam is taken into account. An example is presented and numerical results are compared. The results show that the additional longitudinal forces calculated with the new model are less than those of the previous, especially in the case of the flexible pier bridges. The new model is also suitable for the analysis of the additional longitudinal force transmission between rails and bridges of ballastless track with small resistance fasteners without taking the sleeper displacement into account, and compared with the ballast bridges, the ballastless bridges have a much stronger additional longitudinal force transmission between the continuously welded rails and the bridges.     

梁纵截面单位长度法向内力计算公式

用纵截面把梁分成两部分,将梁横截面的内力分解到这两部分的横截面上,同时在纵截面上也得到对两部分的作用力,利用两的平衡条件和纵截面上的变形协调条件建立求解方程,推导出梁纵截面单位长度法向内力的计算公式。该公式经例题检验,在狭长矩形截面梁受均布力时,能得到纵截面正应力的精确解;在狭长矩形截面梁受正弦波型分布力时,当载荷集度变化不大或梁足够细长,也能得到足够精确的纵截面正应力。并对Ｎｏ．６３ｃ工字钢梁受     

多径环境中目标参量的估计

提出了一种多径环境中目标参量估计的新方法，这种方法以时延估计为基础，将目标的方位信息以及速度信息作为状态参量，利用卡尔曼滤波对各个参量进行估计。作者对该方法进行了理论分析，并利用解卷积时延估计技术在ＰＣ机上做了仿真仿真结果表明，这种方法能够准确地估计出多径环境中目标的方位信息和速度信息。     

基于ANSYS的简支梁桥柔性墩纵向力分配研究

在刚度耦合模型的基础上,采用大型有限元分析软件ANSYS建立三维实体有限元模型,对连续桥面简支梁桥柔性墩纵向力分配进行仿真分析,通过有限元模拟值与采用刚度耦合模型得到的计算值对比分析表明,刚度耦合模型计算墩顶水平力是合理的,结果是可靠的.采用节点耦合的方式模拟板式橡胶支座,采用弹簧-阻尼单元模拟滑板支座是可行的.     

Approach of simultaneous localization and mapping based on local maps for robot

An extended Kalman filter approach of simultaneous localization and mapping（SLAM） was proposed based on local maps A local frame of reference was established periodically at the position of the robot, and then the observations of the robot and landmarks were fused into the global frame of reference. Because of the independence of the local map, the approach does not cumulate the estimate and calculation errors which are produced by SLAM using Kalman filter directly. At the same time, it reduces the computational complexity. This method is proven correct and feasible in simulation experiments.     

生物力学模型导引的心肌运动与材料参数对偶估计

针对传统心脏图像分析方法割裂运动分析和材料分析的局限性和扩展卡尔曼滤波器联合算法引入互协方差矩阵具有收敛慢的问题,提出基于卡尔曼滤波器和扩展卡尔曼滤波器的对偶滤波器算法,该方法用有限元方法表达心脏求解域,连续生物力学模型作为逆问题的约束,在状态空间框架下将运动状态向量和材料参数向量分别置于2组状态空间方程中,用相应的滤波器进行交替迭代估计,从而实现心肌运动状态和材料参数的同时重建.结果表明,该方法能够有效地提高估计精度和收敛速度,缩短计算时间.