"The egg model would make a nice dinosaur egg" I thought to myself, especially of a dinosaur hatchling could cautiously peep out of the cracked top of the egg. With the egg project as a starting point I had a look round the site for suitable mechanisms. The Watt Linkage is a simple but interesting way for creating straight line motion and the Geneva Drive would work as a nicely hesitant drive. Up a bit – stop, up a bit- stop, then down back into the shell. I kept the mechanisms basically the same as they were in the original download projects but changed the box sizes so that they matched up with each other.
That done it was just a case of joining them back to back.
Inside, I've added an arm to the Geneva Drive output wheel and a drive pin that locates in a slot on the watt linkage.
Next, I'll take the egg project…
…and fit it to the top of the two boxes.
The first draft seems to work well. Next, I'll be making a few tweaks to the base then adding an egg .
Check back for a progress report soon.