车载激光扫描系统及其在城市测量中的应用

激光扫描仪在测量中的广泛应用使得车载扫描系统的研究成为热点,本文首先介绍了车载激光扫描技术的原理和特点,然后详述了其在城市测量中的应用,最后指出当前应用中存在的问题及需要解决的关键技术。     

SICK-LMS 291激光扫描仪单机检校方法研究

激光扫描仪测量是获取三维空间信息的最有效方法之一。本文通过设计针对性的试验分析了SICK-LMS291激光扫描仪的测角和测距精度,建立数学模型分别求解了其距离和角度改正参数,结果表明改正后的激光扫描仪距离和角度测量精确度都得到了明显的提高,验证了本文采用的检校方法的可行性。     

车载移动激光扫描测量产品综述

对目前市场上一些重要的车载移动激光扫描系统(Mobile Terrestrial Laser scanning Systems,简称MTLS)的性能特点进行了概述。文章首先介绍了移动测图系统的发展历程,对系统组成及特点进行了介绍,然后比较了不同类型车载激光扫描系统的主要特点,比较的数据都来自于各设备厂商提供的材料。从整体看,目前车载移动激光扫描系统已投入到不同行业的实际应用中,大量成功的应用案例表明,车载移动激光扫描测量技术已趋于成熟。     

现代精密工程测量技术及仪器

在现代工程测量中,由于工程的各项技术指标要求越来越高,相应地对测量也提出更高的要求.本文总结了现代精密工程测量中的常见技术及设备,具有一定的参考价值.     

空地一体化地形测量

近年来,以无人机为载体进行地形测量的单位越来越多,但现有无人机成果在高程及房屋两方面无法满足大比例尺要求。为了解决这个难题,本文将地面扫描仪与无人机结合的方式进行作业,结果表明该方法的成图精度完全可以满足1：1000地形图成图规范要求。     

REVIEWS OF GEOGRAPHIC SOFTWARE

Reviews of geographic software in this article: GEOGRAPHY MACCHORO OPS83 Population Analysis on Microcomputers with PC or MS DOS STATPAC GOLD THUNDERSCAN     

基于全站仪交会测量的空间距离校准装置测量方法

空间距离标准装置是校准地面激光扫描仪的重要计量标准器,其标靶球的空间距离测量一直是其难点,目前大多是采用激光跟踪仪来测量。提出使用多台全站仪交会来进行标靶球的坐标测量,首先通过后方交会、免棱镜测量可以快速方便地得到特征点的概略坐标,然后通过互瞄建立定向基准,最后通过整体平差得到高精度的特征点坐标。实例证明,这套系统的精度优于0.1 mm,能够满足空间距离标准装置的校准精度要求。     

地面3维激光扫描仪测量精度试验与分析

地面3维激光扫描仪是一种可进行全自动高精度立体扫描的先进仪器。其特点是可大面积高分辨率地快速获取被测对象表面的3维坐标数据,且所获取的数据具有实时、动态、高密度、高精度等优点。因而,激光扫描测量仪器的精度对工程应用的影响以及对3维点云模型的建立和精度影响至关重要。文章针对瑞格公司所生产的VZ400扫描仪在测量时,距离、入射角度、目标颜色几个因素对精度产生的影响进行研究。利用平面拟合的方法分析精度,得出了随着距离的增加,入射角的增大,会导致地面3维激光扫描仪测量精度降低的定性分析结论．     

Research on laser range scanning and its application

In this paper the development of the technology of the laser scanning is summarized. The principles of laser range scanning are introduced. Based on the laser scanning technology and methods, which are investigated by the authors to survey deposit volume, a surveying system is developed and a practical application is performed. It is shown that the laser-scanning technology has obvious advantages such as measurement precision, automation and visualization of observed data in comparison with the traditional methods. As a result, labor intensity is relieved obviously and work efficiency is promoted.     

Current Behaviour and Dynamics of the Lowermost Italian Glacier (Montasio Occidentale,Julian Alps)

Smaller glaciers (<0.5 km²) react quickly to environmental changes and typically show a large scatter in their individual response. Accounting for these ice bodies is essential for assessing regional glacier change, given their high number and contribution to the total loss of glacier area in mountain regions. However, studying small glaciers using traditional techniques may be difficult or not feasible, and assessing their current activity and dynamics may be problematic. In this paper, we present an integrated approach for characterizing the current behaviour of a small, avalanche‐fed glacier at low altitude in the Italian Alps, combining geomorphological, geophysical and high‐resolution geodetic surveying with a terrestrial laser scanner. The glacier is still active and shows a detectable mass transfer from the accumulation area to the lower ablation area, which is covered by a thick debris mantle. The glacier owes its existence to the local topo‐climatic conditions, ensured by high rock walls which enhance accumulation by delivering avalanche snow and reduce ablation by providing topographic shading and regulating the debris budget of the glacier catchment. In the last several years the glacier has displayed peculiar behaviour compared with most glaciers of the European Alps, being close to equilibrium conditions in spite of warm ablation seasons. Proportionally small relative changes have also occurred since the Little Ice Age maximum. Compared with the majority of other Alpine glaciers, we infer for this glacier a lower sensitivity to air temperature and a higher sensitivity to precipitation, associated with important feedback from increasing debris cover during unfavourable periods.