11.7 - Conclusions & Future Work

Accomplishments

The broad goal of our team was to create a functioning robot dog leg that could feasibly be installed on a full robot dog to enable walking and jumping motions. Some of the specific criteria we had towards our design was being able to do a 20 mm jump and have a forward walking motion. Our design while not having fully met our criteria, did manage to launch itself from the ground accomplishing a jump of approximately 6 mm off the starting position. It also in addition was able to do a walking motion while supported in the air. Although we did not manage to reach our main height goal, we still managed to create a leg that succeeds qualitatively at its stated goals; jumping and full range of motion walking .

Lessons Learned

• Take into account servo motor torque

  • Test to verify and don't necessarily trust the manufacturer provided voltage-torque curve

• Fabricate parts early to do multiple testing rounds

  • Minimize mechanical slop to get better control of linkage

• Research alternate materials rather than 3D printing

  • 3D printed plastic is weak across its layer lines (broke 3x times!)

• Start ideas small before adding to them

  • Build one leg before you build a whole robot dog

• Make sure you have proper weight distribution and minimize friction

  • Heavy things are hard to lift with servos! Make sure your assembly is up to the task before you have to redesign it. Add washers and WD40 where you can (TLDR WD40 dissolves PLA plastic!).

Future Improvements

Moving forward with our project we would take further into account weight distribution as the major flaw in our design was servo motor weight and the friction on the stand it came with pushing down our robot dog leg not allowing smooth high jumps. Another improvement would be on materials used such that we do not 3D print components of our robot dog leg. Moving forward our team would like to look into fully building a robot dog knowing these constraints and tribulations we faced while building our own, while also adding to our design by introducing features like the hip abductor motors for another additional degree of freedom.

Tips for Future Groups

• Schedule meeting times efficiently

• Make sure size of your design scales with weight of your components

• Double check all specs of your components - test before you fly!

• Do not leave final build until last few weeks of classes have a functional prototype early on

Acknowledgements

We would further like to thank our professor ,Dr. Symmank, and our TA ,Jesus Moreno, on their help and advice getting this project started and the tips which led to our project designs success. In addition, we would like to thank any staff at TIW which helped with trainings and keeping the lab open and ready to use.