Implementation ofaDecentralized Adaptive Control System forthe 12-TETWalker
Philip D. Olivier · 2007
Thepurpose oftheTetrahedral Walker (Tetwalker) project istoextend current spaceexploration into regions currently inaccessible bytraditional wheeled or humanoid robots. TheTetwalker consists ofarms,orstruts, thatjoin atnodestoformatetrahedron. Thestruts will beable tolengthen andshorten, thereby giving theTetrahedron shape- shifting abilities. Therobot will movebychanging thestrut length tochange its center ofmass,causing ittotumble. Another benefit ofsucharobot isthatwhenmultiple units are combined, itisabletoassumemorecomplex shapes. This project focuses specifically onthethird generation Tetwalker (the 12-Tetwalker), whichconsists oftwelve tetrahedral robots combined toformacubewiththeability tocarryapayload in thecenter. Theintention istousethis robot fortheexploration ofextremeenvironments, suchastheMartian andLunar surfaces. Thefocus ofthis subset oftheproject wasto implement HomayounSeraji's Decentralized Adaptive Controller (DAC)totherobot. Thiswouldlessen the needforacentralized brain thatwouldcontrol each strut, whichwouldbeverycomplicated andimpractical toimplement forsuchadevice. TheDAC wouldallow eachstrut toindependently extend toits properposition inthecurrent gait. TheDAC wastobeimplemented in MATLAB aswellasinCforthePIC18F6627 microcontroller. TheDAC wouldbetested byusing the PUMA 560modelpresented inSeraji's paper. After this initial testing oftheDAC,theDAC will betested ona modelforthe12-Tetwalker.