Dynamic Modelling and Control of a Robotic Intracardiac Echo Catheter

Objectives: Currently, the treatment of atrial fibrillation with intracardiac echo (ICE) guidance is tedious and requires simultaneous manipulation of the ablation and ICE catheters. The objective of this work is to develop a robotic ICE catheter, dynamic model and control algorithm to robustly control the ICE catheter inside a beating heart.

Methods: We have developed a model for the robotic ICE catheter based on the Cosserat rod theory that relies on strain parametrization while accounting for the actuator motions, motor and tendon frictions, and the external loads along the catheter body which arise during the cardiac procedure. Parameter estimation of the dynamic model was performed using weight release experiments. Optimal control design (LQR and H-infinity) was simulated to regulate the dynamics of the catheter’s tip position.

Results: The parameters of the catheter were consistent for differing weights and catheters. Preliminary simulation results demonstrate an accurate and robust control of the distal end of the catheter. Experimental validation using an EM sensor feedback and tendons actuation for closed-loop control is currently underway.

Conclusion: The simulation results show that our approach can robustly regulate the dynamics of the robotic ICE catheter in the presence of uncertainties and disturbances within the beating heart environment.