Driving the Robot

Quick Update: I ordered some USB A ports, short USB A to Micro-USB B cables, and breakout kits for the Raspberry Pi so I can proceed in my project.

My next (small) hurdle is to actually get the software running for the robot. The issue right now is that the Raspberry Pi takes a while to actually start up, and at the moment I have to enter in a username and password, then execute the file I want to run, all which requires interaction from me. Ideally, I would just be able to plug in the Pi and have it start running the code which I write, and I think I can easily do this. (find somebody who has already done it and follow what they did)

The issue still remains for actually starting / stopping the program on the Raspberry Pi without unplugging it or having it start when I don't want it to. An easy solution to this would be to have the program automatically start (as I said above) but have nothing happen until I press a button on the robot, which would act as a way to start/stop the robot's program. This is pretty simple to do once I have the Raspberry Pi GPIO pins hooked up to the breadboard, I just need to get a couple buttons. (Not hard to find, I think Radio Shack even has them)

I've decided I'm going to code for the robots in Python, since I have a little experience with it, and somebody wrote a nice library called RPi.GPIO which makes it simple to control the Pi's GPIO pins. More on this in the coming weeks.

Powering the Raspberry Pi

The Raspberry Pi has two options for giving it power: either using the the Micro-USB B port or the GPIO header pins. However, the header pins don't have any protection on them, so if you aren't careful then you could do damage to the Raspberry Pi (which I don't want to do), so I'd rather use the USB B port to power it. The issue is that I will be using a battery pack, so I have to come up with a way to connect the + and - cables from the battery pack to the Micro-USB B port. I only really have two options:

1. Cut a Micro-USB B cable in half, and solder the leads from the battery pack in to the cable, and plug the cable in to the Raspberry Pi
2. Get a USB-A port to hook up to my breadboard, and just use a standard USB-A to Micro-USB B cable to connect the breadboard to the Raspberry Pi

The first option is difficult because each of the individual wires in a USB cable are tiny, and I'm still not that great at soldering. Also, it wouldn't look that nice, and could possibly break if the cable is bent. Therefore, I think the second option would be the better choice, but I don't have a part to do that, so I need to find and order one.

Until I have this part ordered, the bot won't be able to drive itself around, since it will be have to be connected to a USB port.

Robo-building

Quick update this week, since I don't have much to share.

I'm working on getting the raspberry pi setup to run the program to control the robot, hooking up the pins from the pi to the breadboard. Once I have the robot driving on its own, I'll upload a video.