Observer-based controller for microrobot in pulsatile blood flow

We propose an observer-based controller for a magnetic microrobot immersed in the human vasculature. The drag force depends on the pulsatile blood velocity and specially acts on the microrobot dynamics. In the design of advanced control laws, the blood velocity is usually assumed to be known or set to a constant mean value to achieve the control objectives, whereas the sole robot position is measured. We prove the stability of the proposed observer-based controller combining a backstepping controller with a mean value theorem (MVT) based observer. The resulting estimation of the blood velocity is then illustrated and compared to high gain observer results through simulations.