Hexy's First Words

In order for Hexy to understand how to write, he had to be taught the alphabet. There are many ways to skin a cat and I figured that the easiest way to record the required letter paths was for me to write up some Matlab code. Pretty straightforward stuff, just lets the user click through the points that define a letter, which is then written to a text file as a Python if-elif statement.

NB I'm aware that this isn't an open-source offering (Matlab is a commercial product), but I'm no good with Python GUIs. If someone would like to port this, please be my guest :)

Once the if-elif statement has been generated, just needed to be packaged with my full robot IK code and made to step through a string, letter by letter.

The fully modified PoMoCo can be downloaded from my GitHub repo. It's not especially efficient with the code or packaged in a sensible manner, but it does muddle by to demonstrate the required functionality.

So here it is. Hexy writing his first words:

Now I know that a good metric for the simplicity of a programming language is the ease at which you can make a Hello World program. In the case of Hexy, I've got to admit it's fairly tricky. It's taken me two months to get to this stage and even so, Hexy as a console output method isn't great. Don't get me wrong, it's not as hard as Malbolge, but this really doesn't feel like Hexy's calling.

If you'd like your very own signed postcard by Hexy, please get in touch!

Inverse Kinematics: Part 4 - Full Robot Solution

Success! Final few sets of measurements later and I've got enough information to turn the full leg IK solution from my last kinematics post into a set of functions that allow placement of any leg to a co-ordinate defined in a Hexy body-centric co-ordinate system.

This should allow Hexy to use that pen he's learned to hold to write, also new walking gaits (with minimum programming effort), body rotations etc. I've included all the maths that I used to get to this position (referencing my previous posts where necessary), put in some new code snippets, plus there's a Moves attachment at the end that wraps it all up for an IK Hexy demo :-)

[WARNING: maths in post]
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Inverse Kinematics: Part 3 - Full Leg Solution

Quick progress this time! Given that the hip joint is orthogonal to the lower two joints (who's positional solution was wrapped up in the first post) it's an almost trivial step to extend the maths to cover three leg joints and a foot position in three dimensions. Complication is that this new set of leg solutions is just going to introduce another coordinate system. By the time I get to finishing up the whole of Hexy, I'm going to be knee-deep in them!
[WARNING: maths in post]
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Inverse Kinematics: Part 1

Pen was put to paper today (and yesterday) to start to understand exactly how Hexy moved. Because I'm well aware just how little maths can fit into my brain at any one time, I decided to reduce the scope of the problem considerably from a whole robot to just part of one leg. This means that instead of having equations of motion/ position that have 18 degrees of freedom, I only have two.

[WARNING: maths in post]
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