A Fluidic Actuated Soft Robot for Improving Bronchoscopic Biopsy

Abstract

Lung cancer has long been one of the deadliest forms of cancer in large part due to the difficulty in diagnosis when at its earlier stages [1]. Because of their large diameter (i.e., ≈ 6 mm) preventing them from navigating in the peripheral lung, traditional bronchoscopes used in minimally invasive biopsy encounter difficulty when trying to reach smaller, deep-seated lesions [2]. Robotic solutions have been developed to address these limitations in surgical navigation. Commercial robotic bronchoscopy systems, like the Auris Monarch™ and Intuitive Ion™ , con- sist of tendon-actuated continuum robots which focus on navigation and biopsy deeper into the lung periphery [3]. Soft robots present a promising alternative to these commercial robotic systems due to their scalability, in- herent flexibility, and potential for safer interactions with biological tissue, making them well-suited for procedures in the peripheral lung [4]. Furthermore, the materials used in soft robotics are generally more economical and allow seamless integration of soft robotic actuation and sensing mechanisms. Exploration of various actuation methods, such as magnetic and fluidic, have demonstrated navigation capabilities in hard-to-reach areas of the lung and the ability to integrate useful tools, such as needles and cameras [5], [6]. However, with miniaturization, the ability of soft robots to transmit forces and interact with the surrounding biological tissue diminishes. We propose a 3.5 mm diameter soft robot with em- bedded degrees of freedom (DOFs) for tip steering, tip stabilization, and needle deployment for tissue biopsy in bronchoscopy procedures (Fig. 1). Via soft actuators embedded in its continuum body, the robot can navigate through the lung branches to the target lesion and anchor itself within an anatomical channel. After anchoring, a needle may be deployed from the robot tip using an origami-inspired soft actuator to puncture the target lesion and take a biopsy. The fluidic actuated DOFs embedded in the proposed robot seek to reach deeper into the lungs, actively increase force transmission at the millimeter scale, and distally control the biopsy needle laying the framework for enhanced surgical capabilities in minimally invasive bronchoscopy procedures.