At Christmas I was lucky enough to get my hands on one of the elusive Raspberry Pi Zeros. I didn’t get mine off of the front cover of a copy of the MagPi Magazine as like many people I missed that boat but I did quickly manage to purchase one from thePiHut. The small form factor has presented some opportiunities for my desire to create small form factor mobile robot using the Raspberry Pi but has brought some challenges that have required some further research and development.
In order to use the Raspberry Pi Zero as a controller the first thing I have had to do is learn how to use the device headless (without a monitor.) I did purchase the essentials kit from thePiHut and solder the header connections on following this video, I then watched these two tutorials on how to configure the wifi adapter and ensure that the device can be found without needing to know the IP address. Actually, I have now started doing this to all my raspberry pis. This should mean that if I can purchase more Raspberry Pi Zeros then I should be able to do so without the need for micro HDMI connectors.
So, What’s the plan?
I’ve been granted a sum of money to improve one of our courses that we offer as part of our enrichment courses. At school we currently offer a SQA NPA award in Games Programming this sounds attractive and the pupils like it well enough but they can usually achieve the qualification easily enough but hate every minute of the evidence gathering aspect of this qualification. We also have a surplus of time left over which we use to build other skills and have in the past used our Lego Robotics kits to develop their programming skills. The pupils really love this, creating devices that follow black lines and navigate mazes and leave all sorts of programming opportunities.
I would like to take this further and suppliement these skills using the Raspberry Pis to allow pupils to develop projects from scratch to the point that we could even have our own PiWars.
So, what’s the plan? I’d like to develop my own robot with 4 micro gear motors powered by 4 AA batteries. Have the Pi Zero powered by a battery power pack and other than that I will need to mount an H-bridge motor controller. Extra features which I would like to add are an RGB LED which I plan to have displaying one of 4 colours – flashing orange for forward normal operations, flashing red for turning to port (left), flashing green for starboard (right) and flashing white for astern (backwards.). I would also like to fit an HC-SR04 Ultrasonic Sensor so that the robot could be programmed to run autonomously.
Issues?
So, there are many issues which I can work on and some which are more problematic. I will work on ensuring that I have enough GPIO pins for all the functions as well as the programming Python to thread so that I can run the lights as well as the motors however the current supply of Raspberry Pi Zeros mean that I wouldn’t be able to get devices for a class load of these projects and I am wrestling in my brain about this. It seems that their availability seems to be more of an issue than was seen at first.
When will they be available in sufficient numbers? Will they be supplied by a main manufacturer. So, it’s quite nice at one level that smaller retailers seem to be leading the way with the supply of the Pi Zeros however this isn’t ideal for schools as Local Authorities have approved lists of suppliers and none of these suppliers are on the approved lists. Adding suppliers requires significant financial information from the retailer and takes a significant amount of effort from somebody (e.g. me) rendering this an almost impossible task when you have other things needing done at the same time.
So, will RS components, CPC, Farnell and other similarly large retailers supply the Raspberry Pi Zero so that schools can buy them or not? Otherwise I will need to significantly modify my plans.
Has the $5 price point ruined the viability of an otherwise attractive device?
As sometimes the form factor is the attraction and the price could be the stumbling block if it’s preventing manufacturers from developing the Raspberry Pi Zero.