Hello all,
Been a few years since I actually built a robot and since I have never really tried to build anything with legs here we go.
Here is the plan so far:
- 12 DOF using MG90S microservos
- rpi zero w as brainz
- PCA9685 16 channel pwm driver for the many servos
- custom built battery pack out of two 3.6v li-ion cells with BMS
- an ubec to provide the 5v
- sensors TBD
I have all the parts in stock for a while now which is cool
Software wise (still in planning):
- the pi will run a custom build linux image
- the control software will be spawned from an earlier project I've been playing with written in golang using a framework called gobot.io
- more TBD
Currently I'm designing the chassis in FreeCAD, and I think I have a base to work with.

bot_base.png (25.25 kB . 859x751 - viewed 108 times)Of course this is all going to be 3d printed as usual

I'm going to create a github project and add all goodies in there once progress is made.
Enough for now I'll update once I have something to show.
27-11-2019 - First twitch Ok so it's been a while time for some updates.
SoftwareCustom linux - check !
I have managed to create a docker based buildroot system that eventually spits out a sdcard image with all the following goodies:
- by default the image boots configured as a WiFi AP mode so you can easily connect to it.
- you can set it up to connect to your own network by adding a file with network name and password in the boot vfat partitions (details in the readme in the repos I'll amb dd below)
- current filesystem size is about 250 MB
- it's fairly fast to boot I think under a minute
- it will automatically grow the root filesystem to use all the space available on the sd card
- it uses systemd as the init system so you get all the nice stuff
- it has the docker daemon built in in case you want to run docker images - to be figured out if it really helps on a single core system but it might do very well when I manage to build for the raspberry pi 3
- ssh daemon so you can ssh inside
- all the raspberry pi drivers are available however some tweaks are needed in the configuration of the raspberry bootloader to enable them
Now I'm sure I'll be forgetting stuff from the list but there you go.
The build system is hosted here:
https://github.com/TinHead/rpi-sd-builderThe actual sd card image is generated here:
https://github.com/TinHead/rpi-zero-w-generic-docker-sd-card and you can download the latest build here:
https://github.com/TinHead/rpi-zero-w-generic-docker-sd-card/releasesSo far I only got to write a small test program in golang to check all works so no detail on control software for now.
HardwareOk so currently I have the electronics connected, 4 motors (well 5 ish) on. Wiring is a mess but hey it's only the beginning
Pics:
Base and stuff:

DSC_0031.JPG (71.37 kB . 1024x576 - viewed 48 times)Current state:

DSC_0180.JPG (78.75 kB . 1024x576 - viewed 48 times)
DSC_0181.JPG (79.53 kB . 1024x576 - viewed 49 times)And it does move
Till the next one ...
Cheers!
TH