Wednesday, 18 September 2013

Rearming - Part 1

Decided it would be really nice to attend this months Raspberry Jam at Bletchley Park and take my Armdroid along to demonstrate....

This will be a tall order with less than two weeks to go, and considering the nature of the venue, we should be controlling all this from a Raspberry Pi !   Until this weekend, very little consideration has been given to this aspect of the project work.

So on that note, we're going to start reassembly...

Installation of motor pulleys - replacements made over the weekend installed into front, and originals at rear, carefully checking for end-float in the motor shafts as we proceed:

I've been applying Thread Lock to all grub screws

The cracked reduction gearing is still an issue... however with a little drop of superglue to reinforce things, this will allow me to reinstall them for now.   I'm still waiting for the new spur gears to arrive, so this is only a temporary measure:

New timing belts roughly placed in order - Medium, Short, Long, Short, and finally Medium.  Although they have a tendency to spring about the place, they can be easily repositioned once the axle is bolted in place.  All moving parts are lubricated with WD-40, but I also have a Precision Oiler pen for hard to reach parts such as bearings.

As you can see, they went in pretty easily after tweaking things about:

Last job for the evening - installing the reed-switch sensors:

Starting with the motor support bar stiffener - this was fitted loosely, and was not tightened until the switch support bar and sensors had been re-fitted.

Further adjustments will definitely be required - one sensor is touching a reduction gear which means friction will rear it's ugly head

Final adjustments will have to wait until the arm is installed !


Here are a few pictures of the Armdroid shoulder so far :-


Tomorrow, the arm will be bolted into place, and that means I can start fine tuning everything.   If all is well, I'll do another bench test, this time posting the video on YouTube.

I've also been busy setting up my Raspberry Pi with a development environment to start writing the controlling software.   I'll update the blog later with more details on that....