Getting started with Duckietown

The Duckietown foundation aims to make self-driving technology more accessible by providing an open-source platform and teaching materials.

I backed the Kickstarter campaign and got the material to assemble two duckiebots and some road segments.

I’ve currently followed the steps in the duckiebot manual to assemble my duckiebots and have completed camera and wheel calibration.

Here’s a fairly unimpressive video of me testing the motor trim by seeing how closely the robot would follow the centre line when driven forward. It’s not great but probably good enough when combined with feedback from the camera.

Follow this link to see all posts about Duckietown

Review: Learn Robotics Programming by Danny Staple

There is a lot involved in building your own robot: sourcing adequate parts, knowing how to assemble them and then how to get the robot to do things by writing software. Buying a robot kit glosses over these steps as the parts are provided together with assembly instructions and often a software library to make programming simple. Going from building such a kit to your own robot can be quite a shock for this reason.

This is why this book is valuable. It covers a lot of ground! The author, Danny Staple, guides us through the process of building a wheeled robot without relying on a kit. Instead, Danny describes the components required and provides some recommendations but allows for variation. Step by step we are shown how to set up a Raspberry Pi and control motors & servos, read inputs from distance sensors, line sensors, and use the Raspberry Pi camera. Everything, hardware and software, is explained from scratch without assuming any prior knowledge and in an easy to read style. Instead of relying on a library of code Danny shows us how to implement everything required a small feature at a time. He also explains the principles behind why he structures the code as he does; so we learn how to extend the software on our own without it becoming a hard-to-maintain mess.

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Review: Tyrant's Throne by Sebastien de Castell

I can be a sentimental old fool and I’ve been known to shed a tear or two while watching a movie. Parts of “Tyrant’s Throne” by Sebastien de Castell had the same effect on me. I came to the Greatcoats series pretty much by accident not knowing what to expect and the story, world and most of all the characters within pulled me with them until finishing the fourth and final book in the series.

De Castell excels at characterization with engaging heroes with enough flaws to enable us to empathize with them and villains who are so much more interesting than just being pure evil. The first person narrative of Falcio val Mond, first cantor of the Greatcoats, a type of travelling magistrate and expert swordsman takes us on a journey that manages to avoid the classic fantasy quest tropes.

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Migrating from drupal to hexo

For an embarrassingly long time (2015!) I’ve been meaning to migrate my personal web site away from drupal to a static site generator like Hexo. There are several reasons why I wanted to do this:

  • Rather than having my content in a database managed by my service provider, I wanted to manage it the same way I manage source code using version control.
  • I got fed up having to upgrade the software than ran the site (drupal in this case) or pay my hosting provider to support older versions of PHP.
  • You can’t hack a static site and alter content unless the hosting provider’s security is broken or I disclose my credentials

I was running an old version of drupal (see point about my laziness updating the site) and there didn’t seem to be any automatic migration path, so I decided to write some code to do it.

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Moving comments to disqus

Update 26th October 2018
Looks like the article I linked to about migrating comments no longer exists. Disqus provides a number of tools to help with site migrations:

I’ve not been very active on this site this year - sorry!

I’m planning to migrate this site from drupal to hexo and
as a first part of that and also in an attempt to combat comment spam I’ve
moved all comments to disqus - we’ll see
if that helps.

I found the article Manually Migrating Comments from Drupal to
really helpful when working out how to export comments from drupal to

For anyone else thinking of trying out Hexo, John Stevenson has a helpful set
of articles on his blog:

ASK NAO guest blog post: Working with developers

ASK NAO is Aldebaran Robotics’
program to develop applications to help autistic children using the NAO robot.
On the project’s forums Aldebaran Robotics staff, teachers, parents,
caregivers and developers collaborate to produce applications that can be used
to help autistic children.

I was recently asked to write a guest blog post and chose to write something
aimed at helping people unsed to software development to work with developers: developers

Bastille day 2014-- Reading & robots

Last year Robbie and I attended the Bastille day festival in Reading. This year we’ll back back with reinforcements! Carl Clement with Byron and Mike McFarlane with Mistcalf will also be joining us. Carl, Byron, Robbie and I were in Reading recently for an interview and photoshoot with the local newspaper (for the record its Dr. Snowdon, not Mr. Snowden and Robbie not Robby )

Bastile day, Reading is on 12-13 July in Forbury Gardens