Nowadays, highly accurate bathymetry is possible—thanks to GNSS technologies. There’s no other way to find out what’s deep down there underwater. SimpleUnmanned undertook research on Marine Creek lake to find out the depth of the lake over the entire area.
The team had two parts of the lake to explore. One part was surveyed using the rover and base, the second part used data from the local CORS to post-process the results.
Setup for the Missions
For this mission, SimpleUnmanned used:
- Two Reach RS+ units: one as a base and one as a moving rover
- An unmanned surface vehicle (UAV)—a boat to mount the receiver on
- A sonar system installed on the boat to collect data about depth
- A CORS station nearby to get the data for post-processing
Part One: PPK Survey with Local Base
The first step is planning the autonomous mission for the boat. The boat with Reach RS+ rover follows the planned route and records the data for future PPK. While exploring the first part of the lake, the team used a second Reach RS unit as a base. It was set on the shore recording its log to process afterward.
The position data from the Reach receiver was later merged with the depth data from the sonar. Using two data sets, the team created a depth map of the lake. With Reach RS+, SimpleUnmanned managed to achieve centimeter-level survey accuracy.
Part Two: PPK Survey with CORS
The workflow was pretty much the same as at the first site. However, the team chose to use data from the local CORS. The CORS was situated a few kilometers away from the surveyed site.
The boat with Reach RS+ mounted on top of it followed the planned route. The data from the receiver was later processed together with CORS data. The fix stayed stable throughout the whole mission.
There’s no need to integrate Reach RS+ with the boat system when one’s working in PPK mode. However, the team had to keep an eye on the sonar data to be sure it complies with the positioning data.
For more details about this survey check out the video:
Update from 2020
As some of our dedicated readers might know, this is a case study we described a couple of years ago. But SimpleUnmanned is still one of our users, and they continue to work with Reach receivers to create new setups.
Different sizes of the boats require different equipment–that’s why Reach M2 became the first choice for SimpleUnmanned’s small boats. The module is lighter than Reach RS2 and provides better maneuverability for boats under 80 cm. Here are a couple of their new projects featuring Reach RS2 and Reach M2.
And here’s the video of the boat on-site. Check out how smoothly it goes!
Thanks for sharing the new projects with us and keeping us updated!
Reach Receivers for Bathymetry
Both Reach RS+ and Reach RS2 are equipped for working on the water. They are waterproof and make a great fit for lake or river surface surveys. Receivers obtain the accuracy up to a centimeter, receiving the corrections from the bae of via NTRIP/CORS network. The ReachView app is available for iOS and Android. Find out more and choose your receiver for surveys!