George Merlocco has taken gaming to extremes with his “Painsaw” project which involves a Raspberry Pi Zero, an Adafruit TFT, some other gubbinses and a blummin’ CHAINSAW. The chainsaw is an Echo Junior Chainsaw toy and you can find out more details and see more pics by visiting his blog. See it in action in the video below:
Chris Scott and Edwin Jones are running a Raspberry Jam in the Seminar Room of Guildford Library on the 4th June. The event runs from 11am-4pm and you can get more information and register for free tickets here. The video above is of their first Jam in March.
Some things just need to be made. This is obviously what Stephen Coyle must have thought when he created this simple Simpsons episode shuffler with a Raspberry Pi Zero. When you press the yellow (naturally) button on top, the Pi randomly selects an episode which it then plays. Read more here.
This weekend has given me time to work my way through my ‘review pile’. I’m almost to the bottom of the pile now – just one book to go. In the meantime, however, I tried out two motor controller boards from 4tronix.
At the moment, there is a certain saturation in the motor controller board (MCB) market. There are boards available in a variety of form-factors and from various vendors and re-sellers. So, what can a new motor controller board, or indeed two, have to offer?
To answer this question, I got hold of a couple of new MCBs from Gareth at 4tronix who are based in Derby. Gareth’s solution to the market saturation is to build boards that are simply loaded with features. It’s certainly a compelling argument, so let’s see what he’s come up with this time!
First up is the RoboHAT. This is a full HAT-sized, pre-assembled board with the following features:
That’s an awful lot of features, and an awful lot of motors, especially if you use all the outputs for servos.
Installing the HAT is just a case of plugging it in. It has an EEPROM which configures the necessary overlays and turns on I2C. The instructions are simple – download an installation script and run it. Included in the downloads is a Python library and several test scripts.
I used these test scripts to try the HAT out. I connected up a 4xAA battery pack, two DC motors and two servos and ran some of the scripts and off the motors went. Very simple, very well-featured and, for £24 (inc VAT), very good value. You can get hold of one from the 4tronix website.
Second on the review pile was the Picon Zero. This is, surprisingly enough, a Zero-form-factor board. It is pre-assembled and has the following features:
In my opinion, the Picon Zero is actually the superior board in comparison to the RoboHAT. Yes, there is a bit more manual configuration to do (in the form of a manual apt-get installation of the I2C libraries) and yes it is smaller and has fewer power options. And no, it doesn’t power the Pi from the battery pack.
However, it has more output channels (and therefore can be used to control more servo motors) and, intriguingly, it has analog inputs. The option to set the outputs to digital, PWM, servo or WS2812 is terrific and the ability to simply power motors from the Pi’s 5V power source gives you a lot of flexibility to ‘just use it’ without messing about with a battery pack if your motors are low-powered.
I plugged in two micro metal gear DC motors and four (!) servos into the board and powered them all from the Pi’s 5V line with no trouble.
Like the RoboHAT, the Picon Zero has an installation script that downloads a library and several example scripts. Using these scripts made my motors turn and I had a lovely little display of spinny things with very little effort.
The price is £16 (inc VAT), which is very reasonable, and you can get hold of one from the 4tronix website or from The Pi Hut.
These two boards from 4tronix are excellent. Sure, they are a little more expensive than some (but not all) other options, but the number of features on the boards, and the sheer technical beauty of the board design, are great compensation for that. Honestly, if I was looking for a motor controller board that could control loads of motors, there really isn’t much competition and I have no hesitation in recommending them.
Today has been all about trying new things. I tried out a great UPS board from Germany and then moved on to a new board from Alex Eames over at RasPiO.
The Analog Zero is a Pi Zero-sized board that will work with any 40-pin Raspberry Pi. It comes as a kit, to be soldered together. It’s easy enough soldering, even for a beginner with a steady hand. The central part of the kit is an MCP3008 analog to digital converter chip which pushes into a socket that you solder on. The MCP3008 gives you eight analog inputs to use.
So, what can you do with an analog to digital converter? You can use analog inputs and read them on the Raspberry Pi. Analog inputs include potentiometers, gas sensors, temperature sensors… in fact, an awful lot of sensors! As you probably know, one of my pet projects is the Picorder – a box full of sensors. It uses the same MCP3008 chip as the Analog Zero. So, I took some sensors (a soil moisture sensor and a pulse sensor) out of that project and added a new potentiometer and hooked them up with jumper wires.
I then wrote a simple script using GPIO Zero (which has in-built support for a variety of analog-to-digital converters) to read the inputs. To my delight, it just worked! I got readings from 0 to 1 for both sensors and the potentiometer.
So, you might guess by now that I think a lot of the Analog Zero. It makes reading analog sensors a piece of cake!
How can you get hold of one? Well, I’ve spoken to Alex and you can expect to hear news concerning availability in the next 2-3 weeks. I’ll let you know as soon as I know how to get hold of the board. Until then, feast your eyes on my test set-up, complete with messy table!
This time, the guys give their views on the new Pi camera, an IKEA Lack table retro gaming console, Pi Wars 2017 (about which, more later I hope!) and various other pieces of news. They also interview OKtoshi about his Pi distro ROKOS which deals with all kinds of cryptocurrencies. Listen to the podcast now. I really recommend The Pi Podcast – it’s the only one out there after all and, after 21 episodes (!), the guys seem to have hit their stride and relaxed into it.
