Precise position control of shape memory alloy–actuated continuum modules through fuzzy algorithm

Abstract

Development of a fuzzy precise controller for the continuum modules utilizing shape memory alloy actuators is the main focus of this study. To this end, two continuum and flexible shape memory alloy–actuated modules, containing shape memory alloy wires or shape memory alloy springs, are considered as the testbed of the control problem to be tackled. The fuzzy controllers in this application are developed using two strategies in this research. In the first technique, the position errors of the two motion variables of the system are considered in the controller design process. The resulted controller is referred as “error-based fuzzy controller.” In the second technique, which is called as “improved fuzzy controller,” the parameters of the desired configuration of the system, in addition to their errors, are considered in controller design process. This procedure makes it possible to overcome the error-based fuzzy controller drawbacks. In order to validate the simulation results, experimental tests are conducted. Both simulation and experimental results reveal the performance of the developed novel two-stage improved fuzzy controller against error-based fuzzy controller and traditional proportional–integral–derivative controller.