The aim of this project is to lower the barrier of entry into dynamic robotics. After seeing Boston Dynamic's Wildcat I became interested in working on something similar, but was disappointed with what the hobbiest scene had to offer. They all used static locomotion. I wanted it to feel alive!
I hope that if people can see that this style of robotics is reproducible with basic development skills, it will attract a wider range of people to legged robots than just those who want to see a vaguely spider looking device re-implement the same kinematic equations over and over again.
The approach is based on the work of Fumiya Iida and Rolf Pfiefer at the University of Zurich in the mid 2000's. Dr. Pfeifer is well known in the field of embodied cognitive science, and these experiments were an attempt to generate movement in quadruped robots based on those principles.
I put the board together a couple of weeks ago, but have been unable to get it to work properly. I successfully installed the Arduino bootloader on the ATMega, but can't load sketches onto it. From what I can tell it's because the the reset pin is not being held at 5V (for reasons I don't understand). This is confusing as the master Arduino uses the reset pin of the slave Arduino to upload the bootloader.
The FTDI chip also doesn't work. It's hard to debug as I didn't create any test points on the board. It doesn't show up in the /dev directory, and using the FTDI utility doesn't lead me anywhere.
I'm going to leave this board as is for now and keep the failures in mind for the next revision. I will be using QFPs instead of QFNs in case bad solder connections were the cause of the failures (I have re-soldered both chips multiple times, each time inspecting with a microscope). I will also be adding test points to the FTDI chip to help with debugging.
Below are pictures of the soldered board (yes, those are bodge wires). At least it was fun to put together!
- Juicier battery traces with ring terminal connectors
The premise of the design was to keep the components as tight as possible (hence mostly surface mount), have the servo connectors / power connectors on the same side, and the USB connector opposite to the servos / power. This board will be mounted in the rear body of the robot (not much space!) so it needs to be concise and well organized.
I got lucky and the design was sent off the fab immediately after it was submitted, so the boards should be here in around a week. Alright!