Year after year, RoboJackets members continue to push the boundaries of what is possible in competition robotics. The latest iteration of our combat robot Hockii is no exception.
The 12-pound Hockii is a type of combat robot known as a “meltybrain”, which uses its drive to spin and hit opponents with the entire body [read more about the previous iteration here]. After last year’s competition, the team noticed that the weapon tooth was a major weakness. Additionally, the fact that it was integrated with the frame meant it was impossible to replace. Thus the team aimed to make a tooth that was both stronger and replaceable.
Mounting the tooth to the frame introduces additional challenges. An improperly-designed tooth or joint would result in the fasteners breaking and the robot ending up toothless. Hockii’s new tooth slots into the frame to help direct moment loads into the shell, while two large bolts keep it in place.
Team member Martha Leach took the tooth design to the next step. Through her internship at the Mayo Clinic Division of Engineering, she had the opportunity to research and utilize computational design and additive manufacturing tools. She led the team to develop experimental teeth which leverage two unique techniques: topology optimization and generative design.
Topology optimization is a computational technique where a model is iteratively modified to minimize an objective while still meeting a target constraint. In this case, the model was optimized to reduce material while still being able to withstand the load of impact.
Generative design is a newer technique where a designer starts by inputting constraints and features of a part. The software then explores the design space to generate multiple possible parts which satisfy the prescribed constraints.
These two teeth were then printed out of titanium using the Selective Laser Melting (SLM) printing process. The teeth are pictured below.
The team behind Hockii is hard at work preparing all robot systems for the March NHRL competition and hopes to put these new teeth to the test against some of the top 12lb combat robots in the nation.