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

It's business time!

We've now had our first lab session!

We began by checking that we had received all of the correct components that we had ordered before Christmas. At first glance it seemed like we had everything that we asked for, however we soon realised that we had ordered the wrong sized thread for the propellers so the motors couldn't be attached and we had also not received the cell holder for the batteries which we had requested. Another problem quickly arose when we realised the Arduino Uno we had ordered did not come with the USB A/B cable needed to connect it to a computer. Thankfully this was soon remedied thanks to the laboratory technicians who kindly found a cable we could borrow.

Once we finished checking the components we began implementing our designs and then subsequently testing them. Starting with the h-bridges (10 pin L293E) on a logic patchboard, we simulated how the motors would work by receiving a high and low voltage. The motors were then attached and operated as intended. Correctly spinning the motors in a certain direction depending on the input to the h-bridge.

By midday we had tested all of our components aside from the Arduino, we installed the Arduino environment on my surface and uploaded an example program to confirm that it operated correctly. This also allowed us to begin getting to grips with the coding language and environment we would use to implement the logic control and the sonar sensor. The example code can be accessed from inside the Arduino environment website and was used to fade in and out a single LED.

We wanted to confirm that the Arduino would work with the previously mentioned h-bridge so we used a sample code from this website to see how the code effected the motors movement and how/if our components worked together[1].

After lunch we separated our tasks: Drawing the circuit diagram and soldering one of the H-bridges, coding the Sonar component for the Arduino, and began soldering the other H-bridge's 10 pin mounts to some veroboard and the connecting wires. I then tested the soldered component on the logic patchboard to ensure it worked as intended. 

The day ended with the soldering of all 10 pins and its wired connections for one H-bridge finished whilst the other requires the wired connections to be added next week. Ideas on propeller solutions and general water proofing were mooted and some of the programming was done. The circuit diagram will be ready for the next lab session.

Our plans for next week:

1.  Likhitha and Steven will test the sonar and begin the main body of coding.

        2.  Both veroboards will be completed and tested with motors.
3.   Motors will be made waterproof.
4.   Buoyancy and infrastructure of submarine will begin. 


References: 
 [1] Arduino two way motor control, http://www.instructables.com/id/Simple-2-way-motor-control-for-the-arduino/#step3, Feb 2014