After a long hiatus, I decided to resume working on this project.
I bought a USB power supply, that easily powers the Pi with the camera module and wifi dongle running. The 6xAA battery pack is now dedicated to the motors.
I also wrote an android app that communicates with the Pi over wifi. The video shows the current state of my project. I made the app with a smaller screen in mind, so it looks a bit strange on a tablet. The laptop shown at the end of the clip shows the server software running on the Pi.
The next step will be to make use of the Pi's camera module. The plan is to either include a live feed in the android app, or to write a web interface instead.
Update: After a few failed attempts, I decided to ditch the lego. This is what i ended with.
Update: Camera module mounted on a small servo motor.
Actuators / output devices: Two 7.2V 50:1 gear motors
Control method: WiFi
CPU: Raspberry Pi
Operating system: Raspbian Wheezy
Power source: 4 AA batteries powering the Pi, 6 AA batteries for the motors
Good to see another pi project here! cant wait to see your robot moving around.
I never did anything in python, so i have no idea of its capabilites, but software PWM will work fine. The Pi runs so fast, you can PWM from a shell script if you want and still get pretty good results.
I’ll definitely upload a video of it in action, as soon as I solve the power issue.
Yes, software PWM was surprisingly easy to implement. When I was researching the matter, I read several posts from people saying the only solution involved compiling kernel modules designed for software PWM. I guess It’s a recently added feature in the RPi.GPIO library.
Python is a very powerful - yet easy to learn - language. I’ve coded in a few languages, but python is the one I always return to. You should try, if you get a chance :)
So, do you have a web server running on the Pi, and that’s how you control it? I’m looking to do something similar, but am having issues with the control interface.
I don’t know if it’s still relevant, but not, I’m not running a web server. I wrote a very simple tcp server in python that runs on the Pi, and clients communicate with it over wifi.
