The new version (technically the next iteration, as it is far from ‘finished’) of the talking ruler is almost ready. New parts have been printed, the stripboard has been soldered together and connectors added to the various parts.
As there needs to be a wire for each of the touch points on the ruler, which is every 10mm, then it required 16 different ports on the Pico, and therefore 16 single core wires soldered onto the board:
I actually removed the two connectors at the end of the board and replaced them with ones which pointed upwards, as there was not enough space to insert both plugs. I also added connectors for the speakers. It was quite a challenge adding the plugs, as the speaker wires are only about as thick as a few human hairs:
I photographed the set of components that need to go inside the housing, which you can see will be a challenge to fit – an exercise in shoe-horning:
The new battery and charger unit have been added to the housing, as well as the on-off switch:
The on-off switch:
Once the new housing has finished printing, it’s time for assembly and to see if it all fits together. Note that I chose multi colour filament to make the numbers stand out:
The assembly of the talking ruler was a little tricky, given the number of wires and components that had to be crammed inside:
The working version is shown below:
You might have noticed that the playback sometimes repeats when holding the pencil onto the contact. This is a limitation of the software – the next version (if there is one) will use a different MP3 player module and be more controllable.
The next thing to do is find a collection of suitable candidates to try the ruler out and see how well it works, get feedback on possible improvements and write up. If you’d like to participate, or know of someone with a sight impairment that would like to participate, then please do contact me. The user tests will be held in East London (at UEL) and also in Norfolk UK.