document: Nonlinear control of a shape memory alloy actuated manipulator This paper presents a nonlinear , robust control algorithm for accurate positioning of a single degree of freedom rotary manipulator actuated by Shape Memory Alloy -LRB- SMA -RRB- . A model for an SMA actuated manipulator is presented . The model includes nonlinear dynamics of the manipulator , a constitutive model of Shape Memory Alloy , and electrical and heat transfer behavior of SMA wire . This model is used for open and closed loop motion simulations of the manipulator . Experiments are presented that show results similar to both closed and open loop simulation results . Due to modeling uncertainty and nonlinear behavior of the system , classic control methods such as Proportional-Integral-Derivative control are not able to present fast and accurate performance . Hence a nonlinear , robust control algorithm is presented based on Variable Structure Control . This algorithm is a control gain switching technique based on the weighted average of position and velocity feedbacks . This method has been designed through simulation and tested experimentally . Results show fast , accurate , and robust performance of the control system . Computer simulation and experimental results for different stabilization and tracking situations are also presented
doc_bio_tags: B I O O B I I O B O O O O O O O O O O O B O O O O O O O B O O B I I O O O O O O O O O O B O O O O O O B I O O B O O O O O B I I O O O O O O O O O O O O O O O O O O B I O O O O B O O O O O O O O O O O O B I O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O B I I O O O O O B I I O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O B O B O O O O
extractive_keyphrases: shape memory alloy manipulator open loop closed loop variable structure control control gain switching nonlinear control stabilization tracking positioning nonlinear dynamics
abstractive_keyphrases: feedback