This is my first attempt a building a robot powered by a Raspberry Pi.
The base is a Runt Rover Whippersnapper by Actobotics. It was cheap and very easy to put together, and I wanted it to have 4 wheels. My idea was to basically build a Mouse Droid from Starwars, but I'm not interested in making it identical to the ones in the movies. I just want a small autonomous robot.
I was able to get the basic robot working with Python code I wrote myself by using:
- a 2000 mA Powerbank (used for charging cell phones) to power the Raspberry Pi wirelessly.
- a Edimax Wifi dongle to connect to the Pi... though I may try and convert to Bluetooth in the future.
- a L298 Dual H-Bridge motor controller to drive the motors.
- 4, AA 1.5V batteries to power the L298.
This works perfectly and I am very happy about it. I was even able to get the servor working on a testing board, I just haven't connected it yet. I plan to add the PING sensor in the future for collision avoidance.
April 25, 2016:
I am trying to fix the turning problem by replacing the L298 with an Adafruit DC Motor Pi Hat. I'm just learning about all this and I had a couple of messages posted on the Adafruit board but I think I figured it out. With the Pi Hat which I accidentally bought from Robotshop when I was trying to buy the 16 Channel PWM Hat, I will be able to control 4 motors but no servos. So I'll have to get the PWM Hat to control any other servos it looks like. The hats are stackable, but I'll also need to order a taller header bus/thingy/doey to stack them properly.
Of course, I have practicaly 0 soldering experience and I want to practice a few small items first before I try and solder a GPIO header onto a $30 controller board.
Alternatively I might be able to use the PWM at with the L298, but I think the Motor Hat plus the PWM servo hat will make a better solution.
Please let me know if I'm completely screwing up here and if you have any better ideas please tell me!
Videos:
The built in video tool seems to not like my embed codes.
Rover moving back and forth: https://youtu.be/EtUPPmMu4y4
Rover failing to turn properly: https://youtu.be/CWzI2EXhmxQ
Currently travels programmatically, but will add ultrasonic navigation and autonomy.
- Actuators / output devices: 4 motors
- Control method: Pre-programmed, WiFi
- Operating system: Raspbian Wheezy
- Power source: power pack
- Programming language: Python
- Target environment: indoor, outdoor
This is a companion discussion topic for the original entry at https://community.robotshop.com/robots/show/mouse-droid-based-on-runt-rover-whippersnapper-with-raspberry-pi