Creating fully implantable robots that replace or restore physiological processes is a great challenge in medical robotics. Restoring blood glucose homeostasis in patients with type 1 diabetes is particularly interesting in this sense. Intraperitoneal insulin delivery could revolutionize type 1 diabetes treatment. At present, the intraperitoneal route is little used because it relies on accessing ports connecting intraperitoneal catheters to external reservoirs. Drug-loaded pills transported across the digestive system to refill an implantable reservoir in a minimally invasive fashion could open new possibilities in intraperitoneal delivery. Here, we describe PILLSID (PILl-refiLled implanted System for Intraperitoneal Delivery), a fully implantable robotic device refillable through ingestible magnetic pills carrying drugs. Once refilled, the device acts as a programmable microinfusion system for precise intraperitoneal delivery. The robotic device is grounded on a combination of magnetic switchable components, miniaturized mechatronic elements, a wireless powering system, and a control unit to implement the refilling and control the infusion processes. In this study, we describe the PILLSID prototyping. The device key blocks are validated as single components and within the integrated device at the preclinical level. We demonstrate that the refilling mechanism works efficiently in vivo and that the blood glucose level can be safely regulated in diabetic swine. The device weights 165 grams and is 78 millimeters by 63 millimeters by 35 millimeters, comparable with commercial implantable devices yet overcoming the urgent critical issues related to reservoir refilling and powering.

A fully implantable artificial pancreas (AP) still represents the holy grail for diabetes treatment. The quest for efficient miniaturized implantable insulin pumps, able to accurately regulate the blood glucose profile and to keep insulin stability, is still persistent. This work describes the design and testing of a microinjection system connected to a variable volume insulin reservoir devised to favor insulin stability during storage. The design, the constitutive materials, and the related fabrication techniques were selected to favor insulin stability by avoiding—or at least limiting—hormone aggregation. We compared substrates made of nylon 6 and Teflon, provided with different surface roughness values due to the employed fabrication procedures (i.e., standard machining and spray deposition). Insulin stability was tested in a worst case condition for 14 days, and pumping system reliability and repeatability in dosing were tested over an entire reservoir emptying cycle. We found that nylon 6 guarantees a higher insulin stability than Teflon and that independent of the material used, larger roughness determines a higher amount of insulin aggregates. A dedicated rotary pump featured by a 1-μL delivery resolution was developed and connected through a proper gear mechanism to a variable volume air-tight insulin reservoir. The microinjection system was also able to operate in a reverse mode to enable the refilling of the implanted reservoir. The developed system represents a fundamental building block toward the development of a fully implantable AP and could be advantageously integrated even in different implantable drug delivery apparatus (e.g., for pain management).

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Aortic heart valve replacement is a major surgical intervention, traditionally requiring a large thoracotomy. However, current advances in Minimally Invasive Surgery and Surgical Robotics can offer the possibility to perform the intervention through a narrow mini thoracotomy. The presented surgical robot and proposed surgical scenario aims to provide a highly controllable means for efficiently conducting valve replacement by endoscopic vision. The robot, consisting of a series of joints, is a cable actuated manipulator for reaching the operative site and delivering the valve at the required position. The robot is equipped with endoscopic cameras (to find the hinge points) and three stabilizing flaps (to stabilize the manipulator) for guarantying the proper valve placement. The manipulator is validated by experimental results of flaps' force and camera visions in artificial vessels.