So you have some Raspberry Pi robots every now and then in the magazine. This may sound like a stupid question but… what is a Raspberry Pi robot?
It’s quite simply a robot that is powered, or can be powered, by a Raspberry Pi. Nothing too complicated to it – well, apart from actually making the robot and getting it to talk to the Pi. That can be very complicated.
So it’s not a special model of the Raspberry Pi?
No, it’s not a Model Bot Raspberry Pi or whatever they would call it. Just a plain Raspberry Pi Model B or B+, connected up to a robot chassis via the usual mount points or with a bit of sticky tack or glue depending on how cavalier you’re feeling.
What about the compute module?
Yeah the compute module works as well – in fact it can work a lot better as it has 200 GPIO pins when connected to the I/O board, compared to the 26 or 40 of the other Raspberry Pi models. Although with a bit of know-how and a fair few components you can get it to run a robot without actually needing the I/O board.
So the GPIO port is what powers these robots then?
The pins allow you to read data and activate circuits and motors, which is just about everything you need to do on a robot. You could use the camera port and USB ports for things like a video feed or connecting plug-and-play devices. However, the majority of what
you will be able to make a robot do will be via the GPIO.
Can these robots use anything else to power them?
Sure, some are pure Raspberry Pi, some are a mixture between Pi and Arduino and others can still be controlled by either a Pi or with an Arduino device like an Uno or Leonardo. The Arduino stuff is usually good for controlling servos as that’s what it’s designed for, whereas the Pi has more processing capabilities for analysing data.
Can all Arduino robots be controlled by a Pi and vice versa?
With enough wire, components and patience it probably can be, but there are varying levels of difficulty in that. Some of the robot parts will require more control than others, for example. The easy answer is no, not really.
Can any robot be powered by a Raspberry Pi?
That’s a similar answer to before really. The Raspberry Pi has a lot of connectivity options and there are a few robots we’ve seen that have been hacked to use the Pi instead of their original intended hardware. One of the limits you start to get is processing power on some robots.
Why is that a limit?
The more sophisticated the robot, the more inputs and input processing is needed. There’s also the hard limit on things to output to because of limited GPIO pins.
What do I need to get started with my very own robot then?
Well kits are usually the best idea. There are small, cheap ones and bigger, expensive ones that can do some really cool stuff. All of them involve varying levels of difficulty while building.