It is certainly not the first hexapod robot based on HXT900 servos, but it is a first for me. The end goal for this bot is to develop the hardware and software on a smaller scale in preparation for a much larger and more complex bot in the future.
It's a lie, this isn't really step 1.. I have iterated several servo layouts (in fact you can see glue marks from past failures in one of the pictures). I started thinking about this years before home 3D printers were even a reality and have failed cutting reliably 2 sheets of ABS, dozens of chop sticks, and even wood on numerous occasions. I honestly gave up on this for about a year due to seeing no way to fulfill my desires of symmetry. Forward to November 2016 and welcoming a Ultimaker 3 into my home and all the sudden the prospect of completing this isn't doomed.
So far I have lied and now I must admit I cheated on the project already, too. However in my defense I wanted to test my new printer, my Solidworks skills are limited , and so I came across a project on thingverse(quite by accident) that was exactly the style and shape I wanted and designed to fit my servos. So I began printing the lower leg portion. The printer passed my test with 6 prints, 0 failures, and only one little corner that didn't stick right on one leg.
I started with the lower leg portion because I am of the belief that it is the most important part of any walking robot. Well the feet more so than leg but on a hexapod it is basically the same thing.
The legs are attached to their servo using 2*(2Mx10mm Bolts & Nuts)
In truth step 1 should probably be drawing out some designs and perhaps doing some math etc etc etc... and I have made some crude cave man like drawings; more suited to use of crayon than pencil, calipers, protractors, straight edges, and other fancy implements. However I wasn't settled on what 3d software until recently and even still I am fighting Solidworks vs Inventor.
Now step 2 will become the actual planning phase, because I must begin looking at leg length and gait.
My current working plan is to use upper leg length equal to the entire length of lower leg.
My "hip" is created with 2 servos glued together, at least at this point. This was a stupid idea really... but at the time I had no idea that I would have a 3d printer to do this. I have 3 of them completed so I need to contemplate if I should try to undo them and print something or just make the other 3 in the same way.
TL;DR = I all but randomly chose some leg piece and printed it 6 times. Time to design around them.