一个inertial navigation system (INS) is a critical part of a surveyor’s armoury. The measurements provided by the INS, including heading, pitch/roll, timing and absolute position, ensure that surveyors can confidently measure their environment, safe in the knowledge that every area and angle is covered precisely.
A strong survey INS for precise applications will provide heading accuracy of at least 0.1°, 2cm or less position accuracy and pitch/roll accuracy of around 0.05°. It should also provide additional features, such as Lidar integration, to help to streamline a surveyor’s work and allow them to do more of what they’re good at…surveying.
有一个几乎无尽的调查和映射应用程序列表，其中INS是一种比使用更具使用的工具。例如，建筑信息建模（BIM），林业调查，沿海监测和基础设施勘探应用程序都可以从INS提供的测量中受益。尤其是从上述测量值中获利的一种应用程序是道路调查。
道路调查
在谈论道路调查时，重要的是要区分道路建设调查和对现有道路的测量，因为这些项目都有独特的要求。
It is very rare that a new road being planned will be able to go direct or ‘straight’ from its origin to its destination. A survey must first be undertaken to analyse the route and identify any potential features that need to be taken into consideration. These can include natural features such as hills and rivers, where a tunnel or bridge may be required, to manmade features such as buildings and other infrastructure that will need to be navigated. Once a route has been identified, the land will again need to be surveyed to identify any slopes or environmental features that an engineer will need to pay attention to during construction.
在这种情况下，INS与LiDAR传感器等调查设备相结合，该系统将为项目团队提供宝贵的信息。绝对位置，再加上惯性测量，将保证所需的路线已得到充分调查，并且已经确定了所有潜在危害，并且可以在下一阶段进行计划。当将INS获得的位置和惯性测量与激光雷达传感器收集的数据配对时，测量师可以创建高度准确的环境3D点云，可以一次又一次地使用该云来分析路线。
It is critical to get this process right first time as anything that is missed can lead to delays and additional unaccounted-for project costs. The absolute, centimeter-level global position accuracy provided by an INS gives the surveyor confidence that the exact route has been mapped and there is no position drift.
就现有道路基础设施而言，调查仍然可能是一项长期的基线调查。但是，与其评估一条路线的适用性，不再是更多地了解道路当前状态，随着时间的流逝而退化以及潜在的危害，例如长满的叶子，新成立的坑洼和/或人为的障碍物。
In the past, this type of road survey has been particularly difficult and there are three main factors to consider: road surveyor safety, road user safety and keeping disruption to a minimum – all whilst collecting the best possible data in the required timeframe. This is not such an issue on minor road networks. However, when the survey moves to busier roads and motorways, it becomes increasingly difficult to ensure safety with little to no disruption.
Innovations in survey technology, such as INS and Lidar integration, have enabled surveying to be moved from the road to the roadside or to be carried out whilst driving, thus reducing the risk associated with road surveying.
一个INS will again provide surveyors with confidence that the entire stretch of road has been surveyed and every hazard accounted for. It also provides the data necessary to create a georeferenced point cloud. Additional integration with Lidar sensors will also provide surveyors with the ability to use the point cloud of the existing road for continuous and repeatable analysis.
Furthermore, the INS data coupled with the Lidar data will allow surveyors to understand areas that may need to be resurveyed using accuracy diagnostics.
要了解最新的移动映射新闻，请点击OXTS移动映射LinkedIn页面：OXTS移动映射
UAV-based Mapping
如果是长期的基线调查，例如道路的调查，许多测量师通常会使用移动地图车辆（例如汽车）。但是，由于无人机技术的进步，无人驾驶汽车（无人机或“无人机”）开始改变测量师进行此类调查的方式。
过去，无人机并不总是适合此类工作，因为长期的基线调查可能需要几英里。由于调查（LIDAR）和导航（INS）设备对有效载荷的重量产生负面影响，因此飞行时间往往会大大减少。
Fast forward to today and advances in technology are fast-flowing. New UAV power sources, such as hydrogen fuel cells, are enabling UAVs to stay in the air longer and carry heavier payloads. At the same time, survey technologies such as INS devices are getting smaller and lighter whilst still being able to offer highly accurate measurements.
To keep up to date with the latest UAV-based mapping news, follow the OxTS UAV-based Mapping LinkedIn page:OxTS UAV-based Mapping
Inertial Navigation Systems
A case in point is the newOXTS XNAV650 INSwhich has been developed with surveyors in mind. Its small size (only 77 x 63 x 24mm) coupled with its light weight (just 130g) makes it an ideal partner for UAV and drone-based survey and mapping applications. However, the xNAV650 is not limited to UAV and drone surveying, as explained in more detail below.
Despite its small size and weight, the xNAV650 does not compromise on performance with 0.1° heading accuracy, 0.05° pitch/roll accuracy and 2cm RTK/PPK position accuracy.
这xNAV650 also has additional software integrations and features that help surveyors focus on what they’re good at – surveying.
Lidar sensors are used in many surveys to help surveyors build up a 3D picture of the environment they are surveying. These point clouds provide surveyors and engineers with critical information that helps them make important project decisions – such as decisions about road/highway route analysis and preparation.
But georeferencing this data to take advantage of the benefits mentioned above in this article can, in many cases, take time. Not many surveyors are, or even want to be, software engineers, so whilst the will to integrate INS and Lidar data is there, it hasn’t always been practical – until now!
By using Lidar georeferencing software (such asOXTS Georeferencer) alongside the xNAV650 or an alternative INS from OxTS, users can quickly and easily georeference their Lidar data.
可以在OXTS网站上找到兼容的LIDAR传感器列表：www.oxts.com。您也可以找到有关我们与我们合作的更多信息Velodyne Lidar，，，，HesaiandOusterby viewing the技术合作伙伴页面。
简单的Lidar integration只有一个的一部分OxTS Georeferencer和xNA吗V650 story. Activating the Boresight Calibration feature within OxTS Georeferencer allows users to take advantage of a data-driven approach to calibrating the angles between their navigation (INS) and survey devices.
可以快速，轻松地设置并执行这种校准技术，从而帮助测量师加快“调查时间”。您可以找到有关我们的更多信息Lidar Surveyingand钻孔校准capabilities by downloading the associated brochures from our website.
“作为一名工程师，我不知道一个简单的工具，可以精确地测量INS和LIDAR之间的角度到千分之一度。OXTS使用他们已经为激光雷达测量的工具提供了优雅地解决此问题。在两个反射目标（廉价构建）之间运行十分钟的数据收集是最困难的部分。鉴于有据可查的OXTS指南，下一步是在OXTS GeoreFerencer中选择收集的数据文件并按下“运行Boresight校准校准”按钮的简单问题。它真的是那么简单。在指定了计算的角度后，点云精度甚至显着提高了人的眼睛。”
一个dri Karo, Systems Integration Specialist, SKYCORP
Surveying using an INS
OxTS partner SKYCORP is an Estonian manufacturer of hydrogen-powered drones who successfully used the xNAV650 to conduct a road survey. SKYCORP used:
- 这XNAV650QUAD构成，GNSS定位功能可提供厘米级的位置精度。这使Skycorp能够对道路进行长期的基线调查。
- 一个Ouster OS1-64 Lidarand georeferenced the data usingOXTS Georeferencer。
- Alongside the INS and Lidar, SKYCORP utilized theBoresight校准工具to ensure that the setup was finely calibrated. This produced consistent and repeatable survey data. The setup was made simpler still by using the newOxTS precision time protocol (PTP)使用以太网“插件”设置的功能。
这results obtained are shown below:
Conclusion
Usually seen as the bridesmaid rather than the bride of the surveying world, the importance of the INS in any long baseline survey, not just a road survey, cannot be understated.
为测量师提供高度准确的位置和惯性测量，使他们有信心进入项目的下一个阶段，这是安全的，因为它知道该路线的每个部分都已被涵盖并涵盖了很好的范围。
For more information on how to use an INS to help you streamline survey setup and get the best possible results立即联系OXT。