The first wireless camera pills created a revolutionary new perspective for engineers and physicians, demonstrating for the first time the feasibility of achieving medical objectives deep within the human body from a swallowable, wireless platform. The approximately 10 years since the first camera pill has been a period of great innovation in swallowable medical devices. Many modules and integrated systems have been devised to enable and enhance the diagnostic and even robotic capabilities of capsules working within the gastrointestinal (GI) tract. This article begins by reviewing the motivation and challenges of creating devices to work in the narrow, winding, and often inhospitable GI environment. Then the basic modules of modern swallowable wireless capsular devices are described, and the state of the art in each is discussed. This article is concluded with a perspective on the future potential of swallowable medical devices to enable advanced diagnostics beyond the capability of human visual perception, and even to directly deliver surgical tools and therapy non-invasively to interventional sites deep within the GI tract.

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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.

The design and development of a functional integrated system for gastroscopy is reported in this paper. The device takes advantage of four propellers enabling locomotion in a liquid environment and generating a maximum propulsive force of 25.5 mN. The capsule has been equipped with a miniaturized wireless vision system that acquires images with a frame rate of 30 fps (frames per second). The overall size of the capsule is 32 mm in length and 22 mm in diameter, with the possibility of decreasing the diameter to swallowable dimensions. The capsule is remotely controlled by the user who can intuitively drive the device by looking at the video streaming on the graphical interface. The average speed of the device is 1.5 cm/s that allows for a fine control of the capsule motion as demonstrated in experimental tasks consisting of passing through circular targets. The video system performances have been characterized by evaluating the contrast, the focus, and the capability of acquiring and perceiving different colors. The usability of the device has been tested on bench and on explanted tissues by three users in real time target-identification tasks, in order to assess the success of the integration process. The lifetime of the capsule with active motors and vision system is 13 min, that is, a timeframe consistent with traditional gastroscopic examinations.

Minimally invasive surgery (MIS) has been introduced\ud in the last decades with the goal of making scarless surgery\ud feasible. In general, an MIS approach allows concrete benefits in\ud terms of reduced trauma, quicker recovery times, and improved\ud cosmetics. On the other hand, in its current state, MIS introduces\ud more difficulties for surgeons, due to its intrinsic complexity. This\ud issue has inspired the major technological challenge of designing\ud miniaturized robots able to completely enter the body and to perform\ud surgical procedures under intuitive teleoperation. The dream\ud of achieving a completely minimally invasive therapeutic procedure,\ud while offering the typical advantages of traditional open\ud surgery, has brought to the complete elimination of external incisions\ud by gaining access to the peritoneal cavity through a natural\ud orifice. These scarless procedures are known as Natural Orifice\ud Transluminal Endoscopic Surgery (NOTES) interventions. In this\ud paper, novel approaches to NOTES instruments and platforms are\ud presented, in which modular robots measuring 12 mm in diameter\ud with basic functionalities (manipulation, cutting, vision, and\ud retraction) and multiple degrees of freedom are deployed inside a\ud human phantom and anchored on a supporting frame for the stable\ud execution of tasks. This paper illustrates the general concept, novel design guidelines for the modular robots, and two robotic units successfully assembled and tested with ten users, in order to assess the capabilities of the system in pick and place experiments and cutting tasks. Experiments for the assessing force and accuracy are described as well

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Abstract. This article presents the design of a newly developed 2DoF robotic arm with a novel statically balanced and bi-stable compliant grasper as the end effector for laparoscopic surgery application. The arm is based on internal motors actuating 2 rotational DoFs: pitch and roll. The positive stiffness of the monolithic grasper has been compensated using pre-curved straight guided beams that are preloaded collinear with the direction of actuation of the grasper. The result is a fully compliant statically balanced laparoscopic grasper. The grasper has been successfully adapted to a robotic arm. The maximum force and stiffness compensations were measured to be 94 % and 97 % (i.e. near zero stiffness) respectively. Furthermore, the feasibility of adjusting for bi-stable behavior has been shown. This research can be a preliminary step towards the design of a statically balanced fully compliant robotic arm for laparoscopic surgery and similar areas.

The rise of antibiotic resistance is the main cause for the failure of conventional antibiotic therapy of Helicobacter pylori infection, which is often associated with severe gastric diseases, including gastric cancer. In the last years, alternative non-pharmacological approaches have been considered in the treatment of H. pylori infection. Among these, antimicrobial PhotoDynamic Therapy (aPDT), a light-based treatment able to photoinactivate a wide range of bacteria, viruses, fungal and protozoan parasites, could represent a promising therapeutic strategy. In the case of H. pylori, aPDT can exploit photoactive endogenous porphyrins, such as protoporphyrin IX and coproporphyrin I and III, to induce photokilling, without any other exogenous photosensitizers. With the aim of developing an ingestible LED-based robotic pill for minimally invasive intragastric treatment of H. pylori infection, it is crucial to determine the best illumination parameters to activate the endogenous photosensitizers. In this study the photokilling effect on H. pylori has been evaluated by using a novel LED-based device, designed for testing the appropriate LEDs for the pill and suitable to perform in vitro irradiation experiments. Exposure to visible light induced bacterial photokilling most effectively at 405 nm and 460 nm. Sub-lethal light dose at 405 nm caused morphological changes on bacterial surface indicating the cell wall as one of the main targets of photodamage. For the first time endogenous photosensitizing molecules other than porphyrins, such as flavins, have been suggested to be involved in the 460 nm H. pylori photoinactivation.