Development of a shape memory alloy actuator using generative manufacturing.

A Nitinol hydraulic bellows actuator for the application in minimally invasive surgeries (MIS) has been designed and manufactured. Such application required the actuator to be elastically deformable. This paper explains how the actuator geometry is optimized for large deformations and shows the feasibility of an actuator manufactured by selective laser melting (SLM). Four different shapes were virtually tested using finite element analyses (FEA). Furthermore, multiple samples of the bellows actuator with a U-shaped deformation zone were simulated and manufactured. A test rig was developed to measure deformation and achievable force. Physical tests showed a sufficient performance of the actuator for typical applications in minimal invasive surgery. Technical challenges and potential solutions on the current state of development are discussed. [ABSTRACT FROM AUTHOR]