LOCOMOTIVE UNDERACTUATED IMPLEMENT GUIDED VIA ELASTIC ELEMENTS (L.U.I.G.E.E): A PRELIMINARY DESIGN

This paper presents the simulation and fabricationof a bipedal humanoid system actuatedwith linear springsto producea standing equilibrium position. The humanoid system iscomprised of two leg assemblies connected by a hip bracket. Elevenpairs of springs were attached to the system in locations designedto simulate themuscles and tendons in a humanbody. The assembly was modeled in the multi-body dynamicssimulation software SimWise 4D. Simulations were performed to determine the springs’stiffnessand naturallengths using a top-down heuristicapproach. After a set of springs werefound to produce a good simulated stable position, theywere cross referenced to standard commercially-available parts. Afinalsimulation was then performed toverify that the real-world spring values produced astable system. Working in tandem with SimWise4D, the humanoid assembly was fabricated usingPLA plastic via an extrusion-type rapid prototyping machine. From the results of the simulation, theset of workingsprings were implementedonto the plasticmodel. After final modifications, the assembly then produced astanding equilibrium position. Finally, the assembly was perturbed in several directions to ensure that after the system experienced a displacement it wouldthen return to its original position.