Adding gesture control to the Raspberry Pi with Flick

27 November 2017

Flick, from Pi Supply, is a series of add-ons for the Raspberry Pi that you can use to detect taps, touches and finger movements. There are three devices in the series:

  • The Flick HAT for Raspberry Pi sits on the GPIO pins of a full-size Pi. It's about 6.5cm by 5.5cm
  • The Flick Zero for Raspberry Pi Zero sits on the GPIO pins of a Pi Zero. It's about 6.5cm by 3cm. You can also use the main Flick HAT on the Pi Zero, but the Flick Zero matches the Pi Zero's board size.
  • The Flick Large connects to the Pi's GPIO pins using wires. It's about 15cm by 10.5cm, so you would typically put it on the desk or mount it on a wall.

The Flick HAT for Raspberry Pi Zero, shown mounted on the Pi Zero

The board can be used to detect touches, taps and double taps. The ability to detect taps in five positions (north, south, east, west, centre) means it can be used as a simple five-button interface. It can also detect airwheel gestures (spinning your finger above the board) and the finger position above the board, including height. In my experience, the device can detect heights of up to about 7cm or 8cm above the board. Height detection still works through the case (there's a set of cases available to compliment the device), although the contact gestures (tap and touch) don't work when the device is in the case.

The Flick can also be used to detect flick gestures (hence the name!), swiping across the board from top to bottom or left to right (or in the other directions). This seems to work at a slightly lower height than the maximum height for finger position detection, based on my setup.

There are lots of potential applications for the Flick. The swiping gesture lends itself well to scrolling through options, and the airwheel could be used as a control for volume or similar parameters. The Pi Zero form factor could be used to make a remote control for a robot or other device. The first thing anyone thinks of is probably a theremin, but that remains a cool project and the Flick could be a nice way to add one discreetly to an existing object. Robot projects could use Flick to add the ability to detect touch. One of the endearing things about the commercial Pepper robot is that it responds when you stroke its head, and that kind of feature could be easily implemented using the Flick.

The most promising format is the Flick Large, because it could give you greater freedom for expressive movements, and so open up new creative possibilities. There's lots of potential in creating robot control panels by putting a decorated sheet of paper in front of the Flick Large, indicating where the virtual controls are for tapping or hovering over. If it works through your desk, the Flick Large could be used to add an invisible touch interface to your furniture. Pi Supply has thought of this and designed a case that enables it to be mounted under the desk in this way.

A Python API is in development, and this will be a big help. The flick-demo program is good for testing the Flick and provides some hackable code, but a few "hello world" examples and a documented API would make it more accessible and easier to build into projects. Here's my "hello world" program for position detection, based on stripping down the flick-demo program:

#!/usr/bin/env python

import flicklib
import time
import os

x_pos, y_pos, z_pos = 0, 0, 0

def move(x, y, z):
     global x_pos, y_pos, z_pos
     x_pos = x
     y_pos = y
     z_pos = z

while True:
     print("X:", x_pos)
     print("Y:", y_pos)
     print("Z:", z_pos)

If you're looking to add gesture controls to your projects, or are interested in innovative new interfaces, Flick can be a great addition to your Raspberry Pi. Find out more about the Flick family at the Pi Supply website here. Thanks to Aaron, Francesco and John at Pi Supply for their help with this review.

Permanent link for this post | Blog Home | Website Home | Email feedback

How to Code shortlisted for Educational Writers' award

15 November 2017

Book cover: How to CodeI am delighted to say that my book Super Skills: How to Code has been shortlisted for the ALCS 2017 Educational Writers’ Award. The book was illustrated by Venitia Dean and published by QED Publishing/Quarto.

Each chapter covers a different super skill in coding, using Scratch to make interactive programs and HTML for website design. The book includes one of my favourite Scratch games of those I've created, a platform game called Treetop Catnap.

The judges said: "Providing a lively way into an exciting new subject for all age groups, this book approaches complex ideas with both humour, and beautiful clarity. Full of handy tips and easy-to-understand instructions, it succeeds in making coding a fun activity for both boys and girls."

The other shortlisted entries are:

  • Secrets Of The Sea (Author: Kate Baker; Illustrator: Eleanor Taylor)
  • Fluttering Minibeast Adventures (Author: Jess French; Illustrator: Jonathan Woodward)
  • Genius! The Most Astonishing Inventions Of All Time (Author: Deborah Kespert; Designer: Karen Wilks)
  • Tree Of Wonder: The Many Marvelous Lives Of A Rainforest Tree (Author: Kate Messner; Illustrator: Simona Mulazzani)
  • The Book Of Bees (Author: Wojciech Grajkowski; Illustrator: Piotr Socha; Translator: Agnes Monod-Gayraud)

The winner will be announced at the All Party Writers Group (APWG) Winter Reception at the House of Commons on Tuesday 5th December.

I'd like to thank the team at QED and illustrator Venitia Dean for all their great work on How to Code, and the judging panel and organisers for reviewing and shortlisting the book. You can find out more about How to Code here, and you can play Treetop Catnap below if you have a compatible browser (click flag to start; cursor keys move, space jumps):

[UPDATE: Congratulations to Piotr Socha, Wojciech Grajkowski and Agnes Monod-Gayraud on winning with The Book of Bees! Many thanks to ALCS, the Society of Authors and the APWG for a lovely evening on the Terrace at the House of Commons, and for shortlisting How to Code for the award.]

Permanent link for this post | Blog Home | Website Home | Email feedback

Hear me chat about coding on the Fun Kids Science Podcast

12 November 2017

Last week I dropped in to the London studio of Fun Kids to be interviewed for the Science Weekly podcast. Host Dan asked me about computer code, where it comes from, and how computer languages work. It was a lot of fun taking part in the interview, and I would like to thank host Dan and producer Imogen for having me along. As always with these things, I thought of better answers to some of the questions on the tube home!

Dan and Sean in the studio, with a copy of Coder Academy in Sean's hand

Dan and Sean in the studio

The interview was recorded to coincide with the publication of Coder Academy, which is out now and provides an introduction to Scratch programming and simple web design. The book is aimed at children aged 7-10 years old, and includes lots of interactive activities on the page. You can take Scratch further with Scratch Programming in Easy Steps and Cool Scratch Projects in Easy Steps. Follow those links to get free chapters and bonus content.

You can hear the podcast using the player below. For more episodes, or to find a link to play this one in your favourite player, check out the Fun Kids Science Weekly here.

Permanent link for this post | Blog Home | Website Home | Email feedback

Dip into the blog archive

June 2005 | September 2005 | January 2006 | March 2006 | April 2006 | May 2006 | June 2006 | July 2006 | August 2006 | September 2006 | October 2006 | November 2006 | December 2006 | February 2007 | March 2007 | April 2007 | May 2007 | June 2007 | July 2007 | August 2007 | September 2007 | October 2007 | November 2007 | December 2007 | January 2008 | February 2008 | March 2008 | April 2008 | May 2008 | June 2008 | July 2008 | August 2008 | September 2008 | October 2008 | November 2008 | December 2008 | January 2009 | February 2009 | March 2009 | April 2009 | May 2009 | June 2009 | July 2009 | August 2009 | September 2009 | October 2009 | November 2009 | December 2009 | January 2010 | February 2010 | March 2010 | April 2010 | May 2010 | June 2010 | August 2010 | September 2010 | October 2010 | November 2010 | December 2010 | March 2011 | April 2011 | May 2011 | June 2011 | July 2011 | August 2011 | September 2011 | October 2011 | November 2011 | December 2011 | January 2012 | February 2012 | March 2012 | June 2012 | July 2012 | August 2012 | September 2012 | October 2012 | December 2012 | January 2013 | February 2013 | March 2013 | April 2013 | June 2013 | July 2013 | August 2013 | September 2013 | October 2013 | November 2013 | December 2013 | January 2014 | February 2014 | March 2014 | April 2014 | May 2014 | June 2014 | July 2014 | August 2014 | September 2014 | October 2014 | November 2014 | December 2014 | January 2015 | February 2015 | March 2015 | April 2015 | May 2015 | June 2015 | September 2015 | October 2015 | December 2015 | January 2016 | February 2016 | March 2016 | May 2016 | July 2016 | August 2016 | September 2016 | October 2016 | November 2016 | December 2016 | January 2017 | July 2017 | August 2017 | October 2017 | November 2017 | January 2018 | February 2018 | August 2018 | October 2018 | November 2018 | December 2018 | January 2019 | March 2019 | June 2019 | August 2019 | September 2019 | October 2019 | January 2020 | February 2020 | March 2020 | April 2020 | May 2020 | June 2020 | September 2020 | October 2020 | December 2020 | January 2021 | February 2021 | May 2021 | June 2021 | October 2021 | November 2021 | December 2021 | January 2022 | February 2022 | March 2022 | May 2022 | July 2022 | August 2022 | September 2022 | December 2022 | March 2023 | April 2023 | May 2023 | June 2023 | October 2023 | November 2023 | January 2024 | February 2024 | May 2024 | June 2024 | Top of this page | RSS


© Sean McManus. All rights reserved.

Visit for free chapters from Sean's coding books (including Mission Python, Scratch Programming in Easy Steps and Coder Academy) and more!

Discover my latest books

100 Top Tips: Microsoft Excel

100 Top Tips: Microsoft Excel

Power up your Microsoft Excel skills with this powerful pocket-sized book of tips that will save you time and help you learn more from your spreadsheets.

Scratch Programming in Easy Steps

Scratch Programming IES

This book, now fully updated for Scratch 3, will take you from the basics of the Scratch language into the depths of its more advanced features. A great way to start programming.

Mission Python book

Mission Python

Code a space adventure game in this Python programming book published by No Starch Press.

Cool Scratch Projects in Easy Steps book

Cool Scratch Projects in Easy Steps

Discover how to make 3D games, create mazes, build a drum machine, make a game with cartoon animals and more!

Raspberry Pi For Dummies

Raspberry Pi For Dummies

Set up your Raspberry Pi, then learn how to use the Linux command line, Scratch, Python, Sonic Pi, Minecraft and electronics projects with it.



In this entertaining techno-thriller, Sean McManus takes a slice through the music industry: from the boardroom to the stage; from the studio to the record fair.

Walking astronaut from Mission Python book Top | Search | Help | Privacy | Access Keys | Contact me
Home | Newsletter | Blog | Copywriting Services | Books | Free book chapters | Articles | Music | Photos | Games | Shop | About