Events, Raspberry Jams

Potton Pi & Pints Raspberry Jam – Saturday, 23rd November, 2019 from 1pm-5pm

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Fancy doing some Raspberry Pi, Arduino or micro:bit stuff in a relaxed, social atmosphere?
Fancy a chat with fellow geeky-type people?
Fancy finding out about the Raspberry Pi and other boards from first principles?
Then, the “Potton Pi & Pints” Raspberry Jam is for you!

What?

This is an informal family-friendly event from the same team that brings you the Cambridge Raspberry Jam and Pi Wars.
We start at lunchtime and encourage people to bring along their projects to Show and Tell or to come along and find out more about the Raspberry Pi, micro:bit or Arduino and what they can do. We set up some pi-topCEED Raspberry Pi workstations for general hacking, but you’re welcome to bring your own equipment along.

This event is an ideal opportunity to get some one-on-one help with setting your Pi up or to get assistance with an ongoing project.

If you want to drop in and learn something new, we supply some Raspberry Pis, worksheets and electronics so you (and your kids, if you have them!) can get hands-on.

Where?

The event is being held in Potton, a small town on the Bedfordshire/Cambridgeshire border, at The Rising Sun, a family-friendly, dog-friendly pub. Food is available all day and is of the pub-grub variety: generously-portioned and reasonably-priced. You can read more about The Rising Sun on their website.

We’ve arranged to use the upstairs function room which has tables and chairs and plenty of space for your projects or just for talking if that’s all you want to do.

This event is a real social for Pi enthusiasts and we’re hoping it will be nice and relaxed with none of the stress and frantic nature of the usual CamJam and Pi Wars! Kick back, unwind and do stuff with your Pi.

Equipment

We’ll be supplying a few Raspberry Pi workstations in the shape of pi-topCEEDs, keyboards and mice. All you have to do is come along. We’ll have some of our worksheets with us so there’ll be some activities for kids available.

Show and Tell

Feel free to bring your own Pi (or Arduino, micro:bit or other) project and whatever other electronic wizardry/gadgetry you happen to have. Please bring a 4-way adapter and extension cord just in case we run out! 🙂

Stay for a meal or a drink

At the end of the Jam (5pm-ish), feel free to join us for a meal/drink/chat. We generally go on into the evening! Everyone is welcome, so feel free to bring the whole family!

Safeguarding

Questions

Any questions can, as usual, be addressed to Tim Richardson (tim@potton.me.uk) and/or Michael Horne
Industry, Robotics

Raspberry Pi and micro:bit robot maker Dexter Industries acquired by Modular Robotics

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American educational robotics company Dexter Industries has been acquired by fellow American robotics company Modular Robotics. Dexter Industries, the company behind the excellent Raspberry Pi-based GoPiGo and the micro:bit-based Gigglebot as well as several others was merged into Modular Robotics back in July. Since then, they’ve been integrating their operations. Modular Robotics, based in Boulder, Colorado, make Cubelets – a fantastic way to get your kids into physical computing and robotics. You start off without a screen, assembling the blocks together, before moving on to using Blockly to program more advanced behaviour.

For now, both product lines are expected to continue, which is very welcome news for this blogger – the GoPiGo in particular is a brilliant robotics kit and the visual programming environment/software that goes with it (Bloxter) is first-rate, providing a user-friendly interface to help get you started with programming your robot. I reviewed the kit and the software a couple of years ago and it’s a great starting point.

It will be interesting to see how things progress as the companies innovate and work together to create new, exciting ways of encouraging kids of all ages to get into robotics.

Art, Making, Music, Tutorials

The answer, my friend, is written on a Raspberry Pi 3 in this wind chime installation

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At The Minories Galleries in Colchester, something is travelling on the wind. Sound artist Frazer Merrick has taken a set of wind chimes and connected them up to a Makey Makey board. The Makey Makey is then connected to a Raspberry Pi 3 which runs a Scratch script. The Scratch script interprets touches and movements of the chimes into additional sound, which are then player back through a set of headphones connected to the Pi. The effect is quite hypnotic:

Frazer has written up how he made it, and you can find the write-up on Instructables. You can read more about the project, and Frazer’s other work, over on his website.

 

Books, Reviews, Robotics

Book review – Learn Robotics with Raspberry Pi (by Matt Timmons-Brown)

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Sometimes, a book comes along that exceeds your expectations. When I saw that Matt Timmons Brown (“The Raspberry Pi Guy”) had teamed up with No Starch Press and that he had a very well-known and respected (though he’d never admit it) Technical Editor in Jim Darby, my expectations were sky high.

TL;DR – If you want a book on Raspberry Pi robotics, this is an excellent introduction, and much more.

Contents

Following a rather nice foreword from Raspberry Pi’s Eben Upton, the book is split into 8 chapters. They are:

  1. Getting up and running
    All about setting up your Pi and getting to a screen where you can start programming.
  2. Electronics basics
    A great chapter to help you understand basic components, how to light up LEDs, how to read button presses, etc. All basic knowledge for your journey into inputs, outputs and command-and-control.
  3. Building your robot
    Takes you through the physical construction using the components you’ve purchased. This includes making the Raspberry Pi and the robot run from the same power source using a cheap buck converter and running the motors using a cheap motor controller board.
  4. Making your robot move
    Includes sections on rudimentary, autonomous movement along a pre-defined route and, happily, turning your robot into a remote-controlled vehicle using a Wiimote.
  5. Avoiding obstacles
    A section about using an ultrasonic sensor to detect obstacles and autonomously drive away from them.
  6. Customising with lights and sound
    A fun chapter showing how to add LEDs and a speaker to your Raspberry Pi to make your robot more attractive and, well, loud!
  7. Line following
    This is all about using a purchased line detector module to follow a black line autonomously.
  8. Computer vision
    This chapter uses a Raspberry Pi camera module and OpenCV to detect and follow a coloured ball.

There are also appendices with a GPIO diagram, a guide to resistors and welcome tutorials on soldering and how to run code on start-up.

The tone of the book

I want to congratulate Matt and his editors on striking just the right tone with this book. It’s conversational, without being “chummy” and has detailed explanations, without getting so technical that you can’t understand anything.

Layout and quality

Remember those “high expectations” I mentioned earlier? As I said, this is a No Starch Press book, and it’s in full-colour, which really makes the diagrams “pop” out of the page. Congratulations to the publishers for producing a really excellent publication.

Here’s a sample page. You can see the quality I’m talking about:

Does it do what it sets out to do?

TL;DR: Yes.

The chapters of the book are well-ordered and their contents well-structured to take you, step-by-step, through the “bread and butter skills” you need as a robot creator. Each component is explained in detail (but not too much detail, as I said before) so that you learn why things work as well as how they work. In other words, it doesn’t tell you what to do to get something working without first telling you about the basic building blocks to get there. It’s a great approach, although it may prove too much for younger readers without adult guidance. I think that’s fine, though – robotics tends to be something which young people don’t get into until they are aged 11+, by which time the tone and content of the book should be within their grasp, albeit with a lot of concentration.

The remote-control section using a Wiimote is, of course, slightly basic (although it does get into using the on-board accelerometer to change the driving speed) but I’m glad it’s there – it will be something people will want to do.

The “meat” of the book, though, is those autonomous sections – distance sensing, line sensing and object following. These are excellent additions as it pulls you into the basic skills that you will need to take part in something like Pi Wars and also prepares you for taking your skills into professional industry.

Conclusion

This book really is an excellent introduction to Raspberry Pi robotics but is also for people who have built their robot already and want to move into autonomous sensing and movement. It is well-written and very accurate, thanks to Matt’s efforts and Jim’s technical editing and is stunning to look at, thanks to No Starch Press. Bravo to all concerned!

Buying it

In the UK, you can pick it up for around £17 at Amazon.

In the USA, you can pick it up for around $25 from No Starch Press (or Amazon).

Opinion, Reviews, Robotics, Shopping

Review of the 4tronix Pi2Go Mk 2 – an exquisite Raspberry Pi robot packed with features and fun

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Back in 2014, robotics specialist 4tronix released the Pi2Go and the Pi2Go Lite, great robotics kits using PCBs as the robot chassis, surrounding a Raspberry Pi.

Now, 5 years (and many products, including this year’s Pi Wars badge!) later, Gareth has designed the follow-up to the Pi2Go, conveniently called the Pi2Go Mk 2. He sent me one to put together and play with, so here goes.

TL;DR – It’s fabulous, it has everything and costs £72 (inc VAT). Get one from the 4tronix website. You can get 10% off everything at 4tronix by using code 4TXPARTY10.

What’s in the box?

The Pi2Go Mk 2 comes in an attractive retail box and contains all the components you need, apart from a Raspberry Pi (all main, 40-pin models are supported – the Zero is usable if you get yourself some extra spacers), an SD card and some rechargeable AA batteries.

The central piece of the puzzle is the Pi2Go main board. It has all the mounting points for the support structure, the motors etc and also has push-fit headers for the extra bits and pieces. It also houses the DRV8833, a standard motor controller, but a very reliable one.

The other big part of the structure is the battery pack. The battery pack comes in several flavours. The default one that comes with the Pi2Go is for 6 rechargeable AA batteries. There is also an option for 7 AAs to give a bit of extra grunt and also a board for two 18650 rechargeable lithium cells which are more resilient to the current used for the motors and, specifically, for the Raspberry Pi 4 (if that’s what you’re using) which uses more juice.

Bit by bit, step by step, putting it together

I decided to put together my Pi2Go using the 7-battery plate, just because.

A full assembly instruction guide is available on the 4tronix website. I followed the guide to the letter. I got a little confused at one point because there were some extra screws provided, but I soldiered on. Everything fitted together “just so” – I would suggest children who are lacking in fine motor skills would need some assistance, but slightly older children with more control would have no problem. It comes with a screwdriver and a hex-nut tool, which was handy.

I particularly like the little motor mounts that hold the motors/wheels to the assembly. Speaking of which, the included wheels are of a new type – very nice, very grippy. I also liked the way that power is delivered to the main board – through the pillar stand-offs – and I really appreciated that no soldering was involved – I could do the whole thing on the kitchen table without worrying about scorch marks!

In about 45 minutes to an hour I’d built up the robot which looked as below:

Another option available is to convert the base model into a 4-wheel drive vehicle by adding two extra motors and wheels. I’ll no doubt do that later, so for now here’s a picture of the made-up 4-wheel drive robot:

Features

The battery boards all have 10 Neopixel-compatible LEDs (SK6812-3535) on them, all programmable. This is a nice addition – everyone likes blinkies, after all 🙂 It just goes to show how much thought is given by Gareth to his designs. He’s even added an on-off switch for the battery pack, which is very convenient!

The main Pi2Go board has, as I mentioned before, push-fit headers for “extra bits”. These are “edge connectors” and there are three of them. In the pack, you’re given an Ultrasonic sensor breakout and an IP address read-out. These plug in as you can see above. The spare edge connector is a great addition because it’s compatible with the Pimoroni Breakout Garden I2C boards. What a terrific idea, and I would say that the 6DoF Motion Sensor Breakout is the one to go for so that you know how the robot is orientated.

Also on-board the robot are 2 infra-red obstacle sensors (on the front corners), 4 light sensors (on all four corners) and 2 line-follower sensors (tucked under the ball-caster assembly on the front).

Handily, Gareth’s added a tactile switch, which I would suggest should be used to safely shut the Raspberry Pi down, although obviously it has other uses, such as starting a series of robot movements. Other features of the robot include 20-slot encoder wheels attached to the motors (and optical wheel sensors to track them) and also four servo connectors on the side of the robot.

This robot kit really does have everything!

In use

After building the kit, I slipped the SD card in, which I had already set-up with SSH and wifi and switched it on. I knew what the IP address was already (I’d paid attention) and SSH’d in from my laptop. I followed the instructions to install the software. The software is a Python library (Python 2, but one can’t have everything) and a collection of scripts. Most importantly, you get a script pre-installed that starts up on boot that shows the IP address on the plug-in display. Other scripts include demos to control the robot using the cursor keys, using the wheel encoders (and without). The scripts basically go through all the capabilities of the main board, but don’t put it together in “one neat package” for you. This is great, because it encourages you to learn how to do it yourself. Documentation is on this page and on there it shows you how to use all the functions in the library.

You can also use Simon Walters’ ScratchGPIO to program the robot – you’ll need to go to his website to find out more, but it’s great that it has that support already!

The costs

The Pi2Go is currently only available from the 4tronix website and costs £72 (including VAT). You’ll need to add a 40-pin Pi, batteries and an SD card on top of that. You may already have all those, though!

As the robot is compatible with all 40-pin models of Raspberry Pi, if you have a spare original B+ knocking around, that’ll do the job, or you can do what I did and use a Raspberry Pi 3A+ to keep the costs down a bit.

The verdict

I am so impressed. Gareth has greatly improved upon his original, already-great Pi2Go series, added feature upon feature, blinky upon blinky and come up with an awesome product. The PCB chassis concept is as good as it ever was and the no-solder assembly is easy enough to do. The use of the edge connectors is a great idea and the compatibility with Pimoroni’s Breakout Garden is a nice addition, giving lots of scope for expansion. The sheer variety of sensors on-board should provide a lot of learning opportunities and the software, in the way it gives pointers rather than full solutions, is a good accompaniment.

The price is, in my opinion, about right. It’s not a cheap kit but it is a sturdy, well-manufactured robot platform sure to give a lot of joy to whoever buys it. I cannot recommend it highly enough as either an introduction to robotics, or as that next move from a simpler kit.

Get your Pi2Go kit here. Don’t forget: For the time being, you can get 10% off everything at 4tronix by using code 4TXPARTY10.