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.

在具有挑战性的条件下进行测量

BM Field uses Leica Geosystems equipment to help make this challenging work possible. Even before he set up his own business in 2008, Aoyama was using Leica Geosystems’ products.

“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.

Before this purchase, the company did some GPS-based VRS and RTK surveys but had difficulties depending on location and time of day to get reception from the relevant type of satellite. Thinking that multiple satellite systems would expand the range of sites where surveying could be applied, Aoyama invested in a new GNSS system.

他说：“引言时，影响是直接的。”“它极大地提高了我们的现场工作效率。”

Tilt measurements eliminate 250 ladder ascents in an irrigation survey

在2019年的贸易展览会上，Aoyama被介绍给Leica GS18 TGNSS RTK ROVER。GS18 T中的“ T”代表倾斜，指其倾斜补偿。

Aoyama说：“在听到它可以通过倾斜的杆子进行准确测量，而无需校准，并且它不受磁干扰的影响，我强烈认为这就是我们所需要的。”“而且我正要为它做一个完美的项目。”

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

没有GS18 T，测量师将需要爬入运河并为每次测量的杆平整。由于他们无法在灌溉运河的底部行走，因此测量下一个点意味着使用GNSS系统爬上梯子，然后再次回到下一个位置。

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.

“When I tried out the GS18 T, I was impressed. It 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.

The company has taken measurements in locations that defeated conventional equipment, such as places where visibility is limited and in large areas of wilderness. Aoyama feels that with the addition of Galileo, the analytical capabilities of the system have clearly improved.

Aoyama continues to add Leica Geosystems GNSS technologies to his company’s surveying toolbox. In 2020, BM Field acquired theLeica Viva GS16GNSS smart antenna and have now a system that makes RTK surveying possible with a small number of personnel.

Aoyama解释说：“如果没有Internet连接，则不能在现场使用VR，但是使用RTK，您不必担心Internet连接。如果将GS16安装在可欣赏天空并用作基站的位置中，则可以将GS18 T置于较厚的灌木丛中，并且仍然使用实时校正进行良好的调查。”

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.

"By combining VRS and RTK, we've significantly expanded the range of applications for GNSS antennas," says Aoyama.

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.

在第一个项目中，BM Field负责绘制一个田地的斜率细节，以制定场外排水的施工计划。

"The site was a large agricultural field. I walked across it taking measurements at 20-metre intervals, and because there were no trees or utility poles to block the signal, the capabilities of GNSS were immediately apparent,” says Aoyama.

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.

“在大约15米高的陡坡上，有许多旧地球围栏的长堆，但是上层栅栏衰老，对角线倾斜。脚下的条件是如此糟糕，以至于我无法用倾斜的乐器衡量，这项工作将是不可能的。” Aoyama说。

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

Expanding survey and post-survey possibilities with GNSS

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.

“这完全取决于网站上的情况。例如，对于Aoyama县的Cedar森林，有一起高大的树木靠近，我们无法使用GNSS。因此，对于该项目，我创建了一些参考点，然后使用总站进行了测量。” Aoyama解释说。

但是，Aoyama建议在可见度较差的位置，必须在绕道而行的位置，以及不方便地引入重型设备的位置。

“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.”

Survey后办公室工作也很简单。

调查网站的GS18 T和控制器利用3D现场软件Leica Captivatein theLeica CS20controller. After returning from the field,Leica InfinityOffice软件用于将测量数据导入PC。然后，在测量CAD系统上创建了计划视图和垂直/水平横截面视图。

“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 particularly likes the navigation function that indicates the next stakeout point on the screen with an arrow. Walking in the indicated direction brings you easily to the measurement point. This function is visually and intuitively easy to use and is especially helpful when moving crosswise.

此外,无穷了data analysis and saved time from potential rework for BM Field.

“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.”

更快的现场工作和降低成本提高了竞争力

引入GS18 T为BM领域带来了一些好处，扩大了可以使用GNS的站点的范围，并提高了现场工作效率

As the GS18 T can be combined with the GS16 to perform RTK, it is now possible to conduct GNSS surveys at sites with adverse conditions, including lack of internet connectivity. Additionally, data can be received from a broader range of positioning satellites. This, together with the improvement of data analysis, has enhanced the capabilities.

By using GNSS extensively, BM Field has also increased the range of sites where measurements can be taken with a very small number of personnel, leading to a reduction in costs. Similarly, since it is no longer necessary to keep the pole vertical, far fewer person-hours are required for on-site work.

A plan view created by surveying a 10ha wilderness

“In the product introduction of the GS18 T, it says '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.

这也增加了利润differentiates BM Field from its competitors.

BM Field is well regarded by its customers for efficiently implementing both VRS and RTK and their knowledge of implementing GNSS in difficult conditions. This has increased work orders from nationwide construction consultancies in Aomori, Iwate and other areas outside Hokkaido.

当他的下一步行动时，Aoyama正在考虑GNSS接收天线Leica GS18 I, which uses Visual Positioning technology.

“I'm always hoping that I'll be able to do more GNSS surveying in adverse conditions that I currently have to give up on. One solution would be the capability to use images to measure point coordinates,” says Aoyama with optimism.

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.