Leica GS18 T expands sites where GNSS can be used

In 2019, BM Field Co., Ltd., a surveying company in Hokkaido, Japan, added the GNSS RTK rover, Leica GS18 T, into their surveying toolkit and has used it on a wide variety of sites since. This has included irrigation canals, wilderness areas and even a landslide site. Working on these sites is easier because the GS18 T measures accurately with a tilted pole, eliminating levelling work requiring high concentration and extra time. The GS18 T has improved work efficiency, reduced costs and enabled GNSS surveys under more challenging conditions.

Virtual reference station surveying boosted by GNSS

BM Field, headed by Tomokazu Aoyama and based in Sapporo, Japan, is a private surveying company with a reputation for completing surveys in challenging conditions. Their customers are building and surveying companies that work with government bodies across the Hokkaido region.

"We've been involved in many agricultural surveys to gain an understanding of field areas and create land improvement plans. We’ve also conducted disaster prevention surveys to understand landslides and create recovery plans. And so we’ve gained a reputation as an experienced company capable of handling work in forests and on steep and rocky hillsides,” says Aoyama.

Surveying in challenging conditions

BM Field使用Leica Geosystems设备来帮助使这项具有挑战性的工作成为可能。甚至在他在2008年成立自己的业务之前，Aoyama都在使用Leica Geosystems的产品。bob综合app下载

“Compared to other surveying instruments on the market, they were the most durable ones in their class. Since then, I’ve continued to use Leica Geosystems’ products because of their robustness and reliability. Even now, our instruments get wet in the rain all the time, but the Leica Geosystems’ products just shrug it off,” he says with a smile.

Aoyama purchased the Leica Viva GS08 plus in 2015 as the company’s first GNSS system. The GS08 plus receives signals from multiple satellite sources, including GLONASS and GPS, and signals are rarely blocked by tree branches or utility poles.

在此购买之前，该公司进行了一些基于GPS的VRS和RTK调查，但根据一天中的位置和时间遇到困难，以便从相关类型的卫星接待处进行接待。Aoyama认为，多个卫星系统将扩大可以应用测量的站点，因此投资了新的GNSS系统。

“On introduction, the impact was immediate,” he says. “It has greatly improved our on-site work efficiency.”

Tilt measurements eliminate 250 ladder ascents in an irrigation survey

At a 2019 trade show, Aoyama was introduced to theLeica GS18 TGNSS RTK rover. The “T” in GS18 T stands for tilt, referring to its tilt compensation.

“After hearing that it can measure accurately even with a tilted pole, without calibration, and that it is immune to magnetic disturbances, I strongly felt that this is what we needed,” says Aoyama. “And I was just about to work on the perfect project for it.”

The project was the survey of an agricultural irrigation canal with a height of more than 1 metre.

没有GS18 T,测量员需要climb down into the canal and level the pole for each measurement. Since they couldn’t walk at the bottom of the irrigation canal, measuring the next point would mean climbing up the ladder with the GNSS system and then back down again to the next position.

The 5-kilometre-long irrigation canal was surveyed at an interval of 20 meters – repeating this method, they would have had to climb up and down 250 times, and it would have been very tough.

“当我尝试了GS18 T,我印象深刻。它could take measurements with the tilted pole so there was no need to climb up onto the canal wall and no need to worry about the bubble. Also, there was no need to carry out troublesome calibration before starting work. So we were able to complete the on-site work in an astonishingly short time but with the same results,” explains Aoyama.

该公司已经在击败常规设备的位置进行了测量，例如可见度有限和在荒野大区域的地方。Aoyama认为，随着伽利略的添加，系统的分析能力已明显提高。

Aoyama continues to add Leica Geosystems GNSS technologies to his company’s surveying toolbox. In 2020, BM Field acquired theLeica Viva GS16GNSS智能天线，现在拥有一个系统，可以使RTK通过少量人员进行测量。

Aoyama explains, “VRS can't be used in the field if there is no internet connection, but with RTK, you don't have to worry about the internet connection. If the GS16 is installed in a location with a good view to the sky and used as a base station, you can carry the GS18 T into thick undergrowth and still conduct a good survey using real-time corrections.”

Another advantage of RTK is that it can save on communication costs. Currently, the company is using RTK for 80 to 90% of its GNSS survey projects.

Aoyama说：“通过组合VRS和RTK，我们大大扩展了GNSS天线的应用范围。”

Surveying overgrown wilderness and other challenging sites

Let’s look at two more examples of sites where the GS18 T has strengthened the surveying capabilities of BM Field.

In the first project, BM Field was responsible for plotting slope details of a field to create a construction plan for under-field drainage.

“该地点是一个大型的农业领域。我以20米的间隔进行测量，因为没有树木或公用极线来阻止信号，所以GNS的能力立即显而易见。” Aoyama说。

The second project was a disaster prevention survey. It was necessary to understand the current situation of an area before building a retaining fence to provide reinforcement and prevent landslides. In disaster recovery surveying, the boundary between the normal area to be maintained and the area that has collapsed must be clarified. So the GS18 T’s tilt compensation was very useful.

“On a steep slope about 15 metres high, there were many long piles from the old earth retaining fences, but the upper ones were ageing and had tilted diagonally. The underfoot conditions were so bad that if I couldn't measure with the tilted instrument, the job would have been impossible,” says Aoyama.

Measuring using a high pole (left) and a screen of the field software Leica Captivate (right)

扩大GNSS的调查和调查后的可能性

Currently, for topographic surveys (including route surveys), Aoyama prioritises the GS18 T and uses the Total Station in locations where the GNSS doesn’t fit the need.

“It all depends on the situation on the site. For example, in the case of the cedar forest in Aoyama prefecture, there were tall trees close together and we couldn’t use GNSS. So, for that project, I created some reference points and then measured these using the Total Station,” explains Aoyama.

However, Aoyama recommends GNSS in locations where visibility is poor, locations where detours must be made and locations where it is inconvenient to bring in heavy equipment.

“For people who say GNSS can’t be used because there are trees, I suggest they try RTK,” Aoyama advises. “Of course, if the site requires millimetre accuracy, I will opt for a Total Station, but if an accuracy of 1-2 centimetres is sufficient, I won’t hesitate to go for GNSS.”

Post-survey office work is also straightforward with GNSS.

The GS18 T and controller at the survey site utilise the 3D field softwareLeica Captivatein theLeica CS20控制器。从田野返回后，Leica Infinityoffice software is used to import the measurement data into a PC. Then, a plan view and vertical/horizontal cross-sectional views are created on a surveying CAD system.

“When you use Captivate on-site, it's convenient because you're constantly made aware of the accurate position and tilt of the pole,” reflects Aoyama. “The on-screen 3D viewer is also easy to read because of the sun mark and colour display features.”

Aoyama特别喜欢导航功能，该功能指示带有箭头在屏幕上的下一个出现点。沿指示的方向行走会使您轻松地进入测量点。该功能在视觉和直观上易于使用，在横向移动时特别有用。

此外，无穷大还改善了数据分析，并从BM字段的潜在返工中节省了时间。

“Infinity offers a higher degree of freedom and adaptability than software by other companies," says Aoyama. “For example, you can change the detailed settings between elevation/descent, use/do not use satellite signals, and so on. This means there is scope for some trial and error in the analysis of the data. In fact, thanks to this flexibility, there have been several occasions where we avoided having to redo site measurements.”

Faster on-site work and cost reductions boost competitiveness

Introducing the GS18 T has brought BM Field several benefits, expanding the range of sites where GNSS can be used and increasing on-site work efficiency

由于可以将GS18 T与GS16结合使用以执行RTK，因此现在可以在不良条件的站点进行GNSS调查，包括缺乏互联网连接。此外，可以从更广泛的定位卫星中收到数据。这与数据分析的改进一起增强了功能。

通过广泛使用GNSS，BM字段还增加了可以使用非常少量人员进行测量的地点范围，从而导致成本降低。同样，由于不再需要保持极垂直，因此现场工作需要更少的人小时。

A plan view created by surveying a 10ha wilderness

”的产品介绍GS18 T,它说s 'work productivity is increased by 20%. But the increase is much higher than that. As an example, a project which would otherwise have taken 30 days before was completed in 10 days, we are now able to do double or triple the work,” says Aoyama.

This has also brought an increase the profits and differentiates BM Field from its competitors.

BM Field受到其客户有效实施VRS和RTK及其在困难条件下实施GNS的知识的知识。这增加了来自Aomori，Iwate和Hokkaido以外地区的全国建筑咨询公司的工作订单。

As his next move, Aoyama is considering the GNSS receiving antennaLeica GS18 I, which uses Visual Positioning technology.

“我一直希望我能够在目前必须放弃的不利条件下进行更多的GNSS调查。一种解决方案是使用图像测量点坐标的能力。” Aoyama充满乐观。

Aoyama’s expectations for the future evolution of Leica Geosystems GNSS surveying technology are high, including the potential for BM Field to use these technologies to master new surveying challenges.