基于ZUPT的宇航员月面导航定位方法研究

发布时间：2018-05-27 13:12

本文选题：宇航员导航 + 零速修正　；参考：《河南大学》2015年硕士论文

【摘要】：随着我国航天运载技术取得了举世瞩目的成就,现在已接近世界先进水平。中国登月,将标志着我们的活动范围扩展到了宇宙空间。登月宇航员在月面的导航定位是国际深空探测领域技术的前沿课题。在载人登月任务中,宇航员导航定位系统是保证宇航员安全、高效地完成任务的关键所在。准确的位置信息可以帮助宇航员更加快速地找到科学目标,并安全回到返回舱直至返回地球。月球表面的环境限制了一些在地球上常用的定位服务(例如全球定位系统Global Positioning System,简称GPS)及传感器设备(例如磁力计)的使用。同时由于缺乏熟悉的参照物,人眼视觉很难辨别距离和大小,所以在空间上很容易迷失方向。因此,宇航员月面导航定位系统要比地球的行人导航困难的多。本论文借鉴地球的行人导航定位,在月面宇航员导航定位中采用惯性测量元件(Inertial Measurement Unit,简称IMU)。IMU具有全天候、不受外界影响、数据更新快,短时间内定位结果稳定等优点,因此适用于在行星表面上等无GPS信号环境下进行导航定位。通过IMU获得的测量数据,可以输出高频率的位置和姿态信息。实际上这种推算方法随着时间的积累存在严重的漂移,不能直接用于导航定位应用中。在导航领域,零速修正(Zero Velocity Update,简称ZUPT)是一种常见的通过约束行走或开车时的瞬时零速度来抑制惯性传感器误差累积的方法。应用于行人导航时,检测脚着地的时刻并将此时运动速度置为0,通过输入该观测量至导航解算中,从而实现对IMU定位误差的抑制,提高定位解算稳健性与精度在本研究中,我们通过实验评估了采用ZUPT算法的宇航员导航定位,在不同运动模式下的精度,以及在探讨了ZUPT算法在长时间下导航的可行性。实验中我们将一个低精度的IMU安装在脚背上。经过初始对准后,通过自动检测运动状态下的零速度状态,并将此时的速度置为0,经过滤波器的反馈补偿,最终校正了漂移误差。实验是在不同硬度的陆地以及模拟微重力环境的水下,采用不同运动模式,如行走、跳跃,沿着不同的路径完成的。通过在模拟月面地形及微重力环境的实验,对多种运动模式下ZUPT定位方法的有效性与精度进行了评价。实验结果表明该方法适用于月面环境中宇航员各类运动状态下的导航定位,在硬地和沙地等环境中的定位精度均优于2.3%,水下模拟微重力环境中的定位精度优于3.1%。
[Abstract]:With the achievement of spaceflight transportation technology in China, it is close to the advanced level in the world. China's lunar landing will mark the expansion of our range of activities into space. The navigation and positioning of landing astronauts on the lunar surface is the frontier of the international deep space exploration technology. In the mission of manned lunar landing, the astronaut navigation and positioning system is the key to ensure the astronauts to complete the mission safely and efficiently. Accurate location information can help astronauts find scientific targets more quickly and safely return to the capsule until they return to Earth. The lunar surface environment limits the use of some commonly used positioning services on Earth, such as GPS (Global Positioning system (GPS) for short) and sensor devices (such as magnetometers). In addition, due to the lack of familiar reference objects, it is difficult for human vision to distinguish distance and size, so it is easy to lose its direction in space. As a result, the astronauts' lunar navigation and positioning system is much more difficult than the Earth's pedestrian navigation. In this paper, the inertial Measurement unit (IMU).IMU), which is used for navigation and positioning of lunar astronauts, has the advantages of all-weather, no external influence, fast data updating, and stable positioning results in a short period of time, for reference to the pedestrian navigation and positioning of the earth. Therefore, it is suitable for navigation and positioning in the environment without GPS signal on the surface of the planet. The measurement data obtained by IMU can output high frequency position and attitude information. In fact, this method can not be directly used in navigation and positioning applications because of its serious drift with time accumulation. In the field of navigation, Zero Velocity Update (ZUPT) is a common method to restrain the error accumulation of inertial sensors by restricting the instantaneous zero velocity while walking or driving. When applied to pedestrian navigation, the foot landing time is detected and the motion velocity is set to 0. By inputting the observation into the navigation solution, the IMU positioning error can be suppressed, and the robustness and accuracy of the positioning solution can be improved in this study. Through experiments, we evaluate the navigation accuracy of astronauts using ZUPT algorithm and the accuracy in different motion modes, and discuss the feasibility of navigation with ZUPT algorithm for a long time. In the experiment, we installed a low-precision IMU on the instep. After initial alignment, the zero velocity state in the moving state is automatically detected, and the velocity is set to zero. Finally, the drift error is corrected by the feedback compensation of the filter. The experiment was carried out on land of different hardness and underwater in simulated microgravity environment. Different motion modes, such as walking, jumping and following different paths, were adopted. The effectiveness and accuracy of the ZUPT positioning method in various motion modes are evaluated by experiments in the simulation of lunar topography and microgravity environment. The experimental results show that this method is suitable for navigation and positioning of astronauts in lunar environment. The positioning accuracy is better than 2.3 in hard ground and sand environment, and the positioning accuracy in underwater simulation microgravity environment is better than 3.1.
【学位授予单位】：河南大学
【学位级别】：硕士
【学位授予年份】：2015
【分类号】：V448;V527

【相似文献】