Last Laboratory Session

On Friday we had our last laboratory session. A lot of this time was spent neatening the circuit by shortening wires, making sure everything was on veroboard and soldered correctly ready to be placed inside the submarine body.

Testing and altering the sonar took most of the laboratory session we had to calculate the speed of sound underwater compared to air, this was approximately ¼ of the speed and so we have to alter the Arduino UNO code. However with these calculations and changing other variables within the code we still struggled to get the sonar working underwater. It is too late to get another component but the team agreed we should have got a sonar device specifically for underwater use rather than choosing a cheaper component.

The rest of the session was spent adding the circuit into the UAV and sealing it in and waterproofing it. Due to the sonar problems it has been left out of the circuit and we have put the backup code on the Arduino.

Finished result:

Unfortunately we have had problems with buoyancy and hoping to sort them out before the bench inspection.

It's Alive!

The submarine is now taking shape and looking more and more like a finished product. Since the last laboratory session the motors have been placed in film canisters with Vaseline and sealed in. Two of these have then been attached to the back of what is to be the submarine, what is currently the top of a plastic bottle. After being sealed using epoxy and PVA glue (as an extra precautionary layer) it was then wrapped in red electrical tape and drawn on for aesthetic purposes.

In the laboratory session an additional power supply and switch were added to the circuit, the diagram of which is in the previous blog post. This was then tested, with it working we are now neatening and finishing the circuit for it to be implemented in the submarine.

We also waterproofed and tested the ultrasound component in the water, though this didn't return good results and so we need to come up with a solution for the next laboratory session

We also successfully sealed and filled the tank we are testing the submarine in. This was done by filled all the holes with cork, both ends then sealed with white tac and then on the outside tape was added for added security.

Below is a video of the motors being tested in the water.

Tasks for next week:

Finish submarine casing

Neaten and finalise circuit

Test AUV as a final product in tank

Evaluate progress and final result