During her summer vacation, Ocean Autonomy Cluster’s (OAC) summer student, Aida Angell, has been building an underwater ROV – Remotely Operated Vehicle. Angell has been building the ROV together with software engineer Simen Tinderholt, and it took them only seven days from start to finish!
The goal of the project was to learn more about the different components that go into a ROV, and all of the material and components used in this project is accessible to everyone. The body of the ROV consists of common cutting boards, the motors are actually galley pumps, and everything is put together with hot glue and silicone.
– We needed a project for this summer’s vacation and what could be better than making a ROV? It was actually Frode Halvorsen, OAC’s cluster leader, that gave me the idea. Halvorsen has been working on a project called eduROV. This project was aimed towards students who wanted to build their own ROV. EduROV provides you with a whole list of components, where to buy them, and tutorials on how to build the ROV, says Angell.
Even though eduROV is open source, buying the parts and building the ROV wasn’t going as smoothly as Aida and Simen hoped.
– eduROV gave us a great starting point, but some of the components were out of date, or no longer available. The electronics manufacturing world can fluctuate from time to time, so it’s important to consider how long a product will be available when selecting components, not only if it fits your application. For example, the specialized pressure sensor the recipe called for was no longer available at Elfa Electronics, but Mouser luckily still had some stock. A lot of the smaller electronics components required were either out of production, or getting expensive when only making a single ROV. Therefore, we had to change some of the components, but we managed to figure out what components we needed. After we had mounted the whole system together, we had difficulties making the casing with all of the electronics waterproof, says Tinderholt.
The duo made more changes to the original ROV by modifying the software running on the ROV. They were able to implement gamepad support and more detailed adjustments to motor output, allowing the ROV to have more speed options, than the initial on/off keyboard controls allowed.
After a week of building, glueing, coding, soldering, and putting all of the pieces together, Angell and Tinderholt can present the final result, a small submersible ROV named ‘ROVert’. The ROV has four motors with a total of 0.129 bhp, 30m cord, weighs 3.8kg, 720p camera,1.2W headlights, and it supports a gamepad. With a smile around their mouth, they add that it is almost waterproof and it goes from 0-100 in never.
– Overall it has been really fun! I have learned a lot about electronics and how all the components on the PCB (Printed Circuit Board) work together. In addition to building the ROV, I documented the whole journey on Instagram and have received a lot of positive responses! People have been with us for the ups and downs, cheered us on, and some even wanted to make their own! I couldn’t have done this without Simen, we have been a good team, says Angell excitedly.
– The challenge of putting this all together, finding the right solutions and improving the ROV where it was possible has been really fun. There are lots of small things that can be better, especially on the electronics side, like adding transistor control on the motors, to enable more fine grained control, better integrating the Raspberry PI on the motherboard to make it simpler to mount, and prevent it from falling into the inevitable puddle of water in the bottom of the casing. Next year I hope we find the time to do this again with improvements, but overall it’s been a lot of fun, Tinderholt agrees.