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

Progress

We have successfully completed the complete circuit diagrams for the UAV:

Here you can see the three motors connected to the two h-bridges which are in turn connected to the Arduino UNO, this also has the sonar attachment and has a voltage supplied to it.

The start of the laboratory session began by using a track cutter and testing the h-bridge soldered last week. We soon discovered it wasn't working and presumed we blew the h-bridge by attempting to test it without the tracks cut last week. Therefore we needed to solder a new h-bridge, this was quickly done and tested, working correctly with the motors on patchboard. Once we were sure of it working a second was produced.

Code also got developed, a blog post containing the current code will be posted shortly. The sonar/ultrasound code was tested using a green and red LED[1]:

Holes were placed into film canisters to house the motor, with one hole for the wires and one for the shaft of the motor[2]. Our plan is to recreate waterproofing recommended on several hobby websites, an example video is below. 

https://www.youtube.com/watch?v=wIcCz5m9LwQ

After tweaking the code and switching the h-bridges and motors from the patchboard to a DC power supply we tested the circuit all together:

Tasks for next meeting:

Complete testing of the circuit

Start waterproofing motors

Implement solution to propeller/shaft connections

Use an external supply (9v) batteries

Think about buoyancy.


References:
[1]Arduino and HC-SR04 Example, http://www.instructables.com/id/Simple-Arduino-and-HC-SR04-Example/, Feb 2014
[2]MIT Sea Pearch Construction Manual, http://seaperch.mit.edu/docs/seaperch-build-october2011.pdf, Feb 2014