Welcome to the Bathymetry wiki!

This Wiki will help you understand different aspects of the project.

Glossary

• Bathymetry: hydrographic survey
• DGPS: Differential GPS (a technique to minimize most of the common errors in two relatively close GPS receivers) more on that in this page
• USV: Unmanned Surface Vehicle

Brief description

Another project with an autonomous boat that logs depth, heuuu, that has already been done... Wait, not that fast. True some projects have seen the light since insert ref here and some are even available in the commerce BUT

1. Here we are dealing with a swarm of USVs. Yes, 5 to 10 USVs scanning the bottom of the sea
2. We want to scan the area where the waves are frequent and contains a lot of energy (we are implementing active stabilization techniques)
3. We use a different kind of propulsion method, and spoiler alert, it is better (for our project) than rudder/propeller type.
4. We built an optimized autopilot that is super secure (Not Pixhawk or APM)
5. APM is not that good for differential steering boat, we got away with selecting our rover as a car but there is a snaking motion we can't seem to remove
6. We use our own DGPS Base station and it is not a 100,000$ solution

I may have your curiosity, now I hope I spiked your attention

The different pages:

1. Our USV electrical layout
2. Our DGNSS
3. The Depth Sensor
4. Our Water-Cooling Loop
5. Our Hull
6. Our Stabilisation Technique
7. The Tests
8. The Failures
9. The Future
10. Other Repo (GGD) https://drive.google.com/open?id=0B9SPJyU6XWlPaXk1R2g3Ym41cm8

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Intro

You are ECE students, you guys are geeks, why would you even need a bathymetry map?

The project started, as 99% of the projects, as "There's got a better way to do this" courtesy of the School of Environment when they were doing their bathymetry maps. The current technique is to use a jet ski manually controlled. the jet ski is equipped with a MBES and a GPS receiver. We can identify 2 major issues, not that I am criticizing their set up, just the "There's got a better way to do this" kicking in.

1. The first issue concerns the use of a human to navigate the jet ski. This task is tiring and repetitive. The human is also prone to error, especially when the task relies on a certain degree of concentration, the human becomes tired and the accuracy diminishes.
2. Having a human piloting on the actual device means adding some space for the pilot, which increases the overall mass which increases the motor size needed which increases the amount of fuel to be taken which increases the structure size and mass for the fuel tank which continues to increase the mass. The back and forth of the increase in properties of the different systems is a well-known problem for plane designers. Here it is present on a smaller scale, but the pattern is still the same. The solution is.... to get rid of the human and to use electric power. The is what we do. the human can sit on the beach, dry and in the shade (NZ ozone layer is not that great).

The second issue is the accuracy itself.

Who is helping to build?

Let's keep it organized per year.

• 2016: A French student from an engineering school in Nantes (6-month internship)
• summer 2016-start of 2017: 4 summer students have been allocated to different projects, including mine
• summer 2017-start of 2018: 2 summer students
• summer 2018-start of 2019: 3 summer students (multi-job PCB & IMU / Stewart platform / Sonar)