Propeller-based wireless device for active capsular endoscopy in the gastric district

Abstract

An innovative approach to active locomotion for capsular endoscopy in the gastric district is reported in this paper. Taking advantage of the ingestion of 500 ml of transparent liquid by the patient, an effective distension of the stomach is safely achieved for a timeframe of approximately 30 minutes. Given such a scenario, an active swallowable capsule able to navigate inside the stomach thanks to a four propeller system has been developed. The capsule is 15 mm in diameter and 30 mm in length, and it is composed of a supporting shell containing a wireless microcontroller, a battery and four motors. The motors enable the rotation of propellers located in the rear side of the device, thus obtaining a reliable locomotion and steering of the capsule in all directions in a liquid. The power consumption has been properly optimized in order to achieve an operative lifetime consistent with the time of the diagnostic inspection of the gastric district, assumed to be no more than 30 minutes. The capsule can be easily remotely controlled by the endoscopist using a joystick together with a purposely developed graphical user interface. The capsule design, prototyping, in vitro, ex vivo and preliminary in vivo tests are described in this work.

Magnetically guided capsule endoscopy

“…Due to the micrometer dimensions of these robots, the flow regime is viscous dominated (low-Reynold's number), unlike the motion of millimeter-sized GI robots in the liquid-distended stomach, where inertial-forces dominant the viscous forces and propeller-based locomotion has been found to be useful. 40 Abbott et al 185 have compared various low-Reynold's number robotic swimming strategies in their article "How should microrobots swim?" In a follow-up article, Peyer et al reviewed bio-inspired magnetic swimming microrobots for biomedical applications.…”

“…24,40 It encapsulates a wireless microcontroller, a battery, and a magnetic turn on/off switch. This blind neutralbuoyancy prototype is wirelessly controlled by a joystick input device and can reach speeds of up to 7 cm s…”

SMAC — A Modular Open Source Architecture for Medical Capsule Robots

“…In Minimally Invasive Surgery (MIS) [1], the MCR must fit the internal diameter of a surgical port, typically from 3 mm to 12 mm. For GI applications [15,16,26,27], we can assume the diameter of commercially available Wireless Capsule Endoscopes (WCEs), (i.e., 11 mm) as the benchmark [28]. Adopting these size constraints as a reference, all of the SMAC hardware modules presented in Section 3.1 have been designed with a round-shaped Printed Circuit Board (PCB) having a maximum external diameter of 9.8 mm.…”

“…This laid the groundwork for the implementation of a number of devices based on one-time hardware prototyping with the support of reconfigurable firmware architecture [6,[15][16][17][18]. By adopting this approach, the firmware development time can be reduced drastically by software layering, but reconfiguring the hardware still requires substantial effort.…”

Inductive-Based Wireless Power Recharging System for an Innovative Endoscopic Capsule

“…However, commercially available pills are limited to screening and are purely passive devices that rely on peristalsis for the propulsion onto important medical target areas, such as the esophagus, stomach, small bowel and colon. In the last decade, many solutions have been explored to embed active locomotion mechanisms onto these devices and allow accurate and controlled navigation [3][4][5][6][7].…”