SHAPE MEMORY ALLOY TENDONS ACTUATED TENTACLE ROBOTIC STRUCTURE Models and Control

摘要

A tentacle manipulator is a manipulator with a great flexibility, with a distributed mass and torque that can take any arbitrary shape. Technologically, such systems can be obtained by using a cellular structure for each element of the arm. Shape memory alloy actuation offers an interesting solution, using the shape transformation of the wire/structure in the moment of applying a thermal type transformation able to offer the martensitic temperature. In order to assure an efficient control of SMA actuator applied to inverted pendulum, a mathematical model and numerical simulation of the resulting model is required. Due a particular possibility SMA actuator connection, a modified dynamics for wire or tendon actuation is presented. For an efficient study a Simulink block set is developed (block for user configurable shape memory alloy material, configurable block for dynamics of single link robotic structure, block for user configurable wire/tendon actuation). As conventional control possibilities were explored, the fuzzy control structure applied in this paper, offer an improved response. A more compact SMA actuation is proposed and experimented. The results are commented.