Comparative study of the various control approaches for the navigation of untethered agents in the vascular network

Navigation of untethered agents such as microscale robots or therapeutic micro-carriers in the blood circulatory network has been an increasing research area in recent years. Indeed, it opens new applications such as surgical, diagnostic, imaging and therapeutic interventions being conducted in the human body. Although many propelling and actuation methods with potential navigation control algorithms have been proposed, very little has been done on proposing a list and a general assessment of potential navigation control approaches taking into consideration the physiological and technological constraints that impact such control implementations. This paper identifies and summarizes the various control approaches for navigation in various sections of the vascular network that present different physiological environments and technical challenges with their main advantages and disadvantages in a control point-of-view.