Modeling and experimental analysis of a new bellow type actuators for active catheter end-effector

The aim of this project is to model a flexible catheter end-effector such as the bellow type actuator developed by Francois (2000). This represents a new type of microactuators. Initially this system was developed for minimally invasive surgery (MIS) in special endovascular treatments of abdominal aortic aneurysms and integrated in a framework of computer assisted surgery. More generally, this type of microactuator can be applied to various kinds of microrobots, such as walking machines, robot hands or any kind of steerable end-effector. The basic principle of the microactuator consists of the control of a moving platform, which is interconnected by three flexible bellows; deformation is controlled independently by internal pressure. The configurations obtained enable the microactuator to follow the desired orientation or position of the catheter end-effector during surgery intervention. In this paper we will begin by developing a theoretical model for the microactuator, dependent on structural parameters. Then we have adjusted the parameters in order to match the theoretical results with the experimental results issued from a 4-scale prototype.