Example of working robot from my desktop

When I use the robot, I connect using SSH. I can also see live camera feed from the webcam. My desktop looks like this:

The window on the left is the camera feed. The window on the right my SSH session on Mac Terminal. Using SSH, I am the Raspberry Pi from my laptop. I can send commands to move the robot, or even write or adapt programs in case the robot gets stuck.

I will post later about exactly how to program the robot using SSH.

Batteries / Battery Power

When I first started out I used the normal Raspberry Pi power supply:

 but as I quickly found out, it is not enough voltage to turn the LEGO Mindstorms motors:

Then I figured out BrickPi had me covered:

That worked but I could still do better (by not using disposable batteries and having the battery last longer):

This is a remote-controlled car battery with a homemade adapter (the construction of the adapter will be in another post). The most important things were:

• the voltage is not above 12v (this would overload the Raspberry Pi) or below 5v (this would cause the Raspberry Pi to restart if the motors used too much power).
• the polarity must be correct (the inside of the connector is positive).
• measure the actual voltage using a multimeter (the battery marked 8.4v actually puts out over 10v).

Getting Started

My name is Leo and I'm in seventh grade.

My robot is now almost completed. Periodically, I will post the steps that I took to build it.

Starting with the hardware: This is my Raspberry Pi with the BrickPi attached in the case that comes with the BrickPi.

I duct-taped an old webcam to the top. It happens to be from Logitech but most webcams will do:

I started out using 8xAA batteries and the BrickPi battery holder but I have since upgraded to a 3000mAh NiMH 8.4v battery that I salvaged from a radio-controlled car. I will do a separate post about power and batteries.

Right now, the robot looks like this:

The worldwide BrickPi robot challenge

The challenge:

Build a robot that can function, be re-programmed, and be controlled from a computer no matter where the robot or computer is located.

(as long as each one is connected to the internet)

The hardware:

• Raspberry Pi
• BrickPi shield
• LEGO Mindstorms motors and LEGO parts
• leftover digital webcam
• battery pack (either 8xAA or repurposed from r/c car)
• USB wifi adapter

The software:

• Dexter Industries' Raspbian for Robots
• Python
• motion (for the webcam)
• OpenVPN (to connect to the internet using Amazon Web Services)