Toward Medical Devices With Integrated Mechanisms, Sensors, and Actuators Via Printed-Circuit MEMS

Abstract

Recent advances in medical robotics have initiated a transition from rigid serial manipulators to flexible or continuum robots capable of navigating to confined anatomy within the body. A desire for further procedure minimization is a key accelerator for the development of these flexible systems where the end goal is to provide access to the previously inaccessible anatomical workspaces and enable new minimally invasive surgical (MIS) procedures. While sophisticated navigation and control capabilities have been demonstrated for such systems, existing manufacturing approaches have limited the capabilities of millimeter-scale end-effectors for these flexible systems to date and, to achieve next generation highly functional end-effectors for surgical robots, advanced manufacturing approaches are required. We address this challenge by utilizing a disruptive 2D layer-by-layer precision fabrication process (inspired by printed circuit board manufacturing) that can create functional 3D mechanisms by folding 2D layers of materials which may be structural, flexible, adhesive, or conductive. Such an approach enables actuation, sensing, and circuitry to be directly integrated with the articulating features by selecting the appropriate materials during the layer-by-layer manufacturing process. To demonstrate the efficacy of this technology, we use it to fabricate three modular robotic components at the millimeter-scale: (1) sensors, (2) mechanisms, and (3) actuators. These modules could potentially be implemented into transendoscopic systems, enabling bilateral grasping, retraction and cutting, and could potentially mitigate challenging MIS interventions performed via endoscopy or flexible means. This research lays the ground work for new mechanism, sensor and actuation technologies that can be readily integrated via new millimeter-scale layer-by-layer manufacturing approaches.

Compliant mechanosensory composite (CMC): a compliant mechanism with an embedded sensing ability based on electric contact resistance

“…A piezoelectric sensing foil in [16] was good at dynamic sensing, but its response was exponentially decayed to a zero in stationary sensing. The force/displacement sensors using PC-MEMS [17] were very compact, but they were not intended for curvature sensing. An origami tile module with a liquid metal based sensor in [18] showed noticeable nonlinearity upon bending.…”

A multifunctional soft robot for cardiac interventions

“…The robotic platform features a shape-locking, expandable stabilization mechanism manufactured with a 2D paradigm used in the fabrication of millimeter-scale mechanisms (57,(63)(64)(65). This stabilization mechanism is capable of shape-locking against the proximal superior vena cava (SVC) without puncturing it, preventing undue harm to the delicate SVC vasculature and the sinoatrial node.…”

Actuators for Implantable Devices: A Broad View

“…An external controller with knobs is maneuvered by skilled professionals for steering, flushing, and imaging ( Figure 3 a). Conventional miniatured actuators based on micro-electromechanical systems (MEMS) are used for tissue sampling and surgical purpose but this often requires operation at a high voltage or temperature [ 90 ]. Russo et al addresses this challenge by developing a low-cost fluid-driven robotic arm that enables safe interaction with surrounding tissues, shown in Figure 3 b [ 48 ].…”