Mojo - A Compliant Quadruped Robot (#3) - Mk3 Leg

I have gone through another design cycle on Mojo the Robot Dog.  This time a quick iteration through the leg design and a new print to test out ideas.  This version is 30% shorter, I am going with 70mm on the leg sections this time.  I trimmed some unneeded weight and bulk on the Tibia. Created a new paw (which I forgot to shorten - so I now have a 'big foot'!).  and to try some ideas around a better compression actuator - which still needs some improvement.

Mojo Leg mk3 w/servo frame

On top you will notice my first sketch at a frame for the robot.  This was a quick sketch to see how things will fit together and get some ideas on how best to scope out the support for servos and controllers.

Many learnings from this iterations - so there will be some design tweaks to come.

• Screw sizes need refined - Rainer at the Inventors meet up gave me some good ideas on how to tune my 3D printer for this.
• the Serial Actuator is going to need an overhaul.  This prototype is not working and more resembles a mock up.  It fits, but is not functional.
• the Frame will need to be wider, longer, and space for the knee actuators and controllers.
• On the Up side, a bit more practice with the CAD is yielding better results in my builds.  Practice always helps - and you get this only from trying!

With a little more success I am working to have a test with the servos to see if they can lift the legs.  I have thought that these 9gm servos will be too weak for the end result, but good enough to start.