All posts by Gerrick Ruffner

GPS Code

Matthew and I have successfully formatted the GPS code for the Arduino into a simple-to-use code. We’ve fixed all of the previous issues regarding the orientation of the compass, and the logic it uses to determine your heading. We’ve also turned what used to be a very convoluted and painfully tedious ‘loop’ into several separate functions. You can view this code from my partner’s post:

http://octomesters.org/robotics/?p=354

Relays

Relay and Blueprint

 

I unfortunately missed posting last week, so I’m getting this one up early.

The majority of my work, so far, has been on creating an efficient and effective H-Bridge circuit for use on the GPS car, the automated drum if necessary, and any future projects that may call for it.

Pictured above, is the layout of the H-Bridge circuit and and the first completed circuit (minus its jacks). Matthew and I worked together to create both the layout and the prototype circuit.

H-Bridge Circuit

Using relays (the big black and white parts) to control the direction of the electric current, this can be used with an arduino to alternate the direction of a motor, since most simple motors in circuits can only be turned on and off. Whereas this one can change direction.

Ink and Solder

And this featured part is an art piece created by Austin “Tony” Shaffer, titled “Ink and Solder”.

Relay

It turns out getting the steering to work on the Arduino is a lot more difficult than I had expected. I’ve had to use a series of relays to control both the steering and the big motor as well.

Unfinished Relay for steering
Unfinished Relay for steering

In troubleshooting the steering relay, Mr. Bahn and I found that, in most likelihood, the Arduino was not grounded. Now that I’ve fixed that, I can solder the circuit together.

Finished Relay for the motor.
Finished Relay for the motor.

GPS Car Update

The GPS Car is coming along nicely. With the smaller switches, we can easily fit them along the the side of the turning arm.

Steering Switches Pic 2

We still need to modify how they will fit in there (the side crushes and bunches up the wires, the switch part is too long, it doesn’t sit high enough to contact the rotating bolt, etc.).  But one step at a time.

Once we have these switches working with the Arduino, we’ll be able to test our code for actually running the car and the steering. A big problem with the programming is that we really don’t have a good way to test whether or not it does what we’re telling it to do. Like a Shakespearean Tragedy, the code comes in three parts right; A setup and calibration establishing the parameters for our steering, then the meat of the code which spews untested logic that may-or-may-not work, then sums itself up with defining certain functions (Drive, Back, Turn, etc).

Hopefully, by this time next week, we’ll be testing our steering.