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This article presents the development of a new concept for an assistive robotic device that can help people as needed, considering their residual physical and cognitive abilities, and, at the same time, increase their cognitive and physical abilities in activities of daily living (ADLs), such as drinking, cooking, eating, personal hygiene, and grooming.

While minimally invasive surgery offers great benefits in terms of reduced patient trauma, bleeding, as well as faster recovery time, it still presents surgeons with major ergonomic challenges. Laparoscopic surgery requires the surgeon to bimanually control surgical instruments during the operation. A dedicated assistant is thus required to manoeuvre the camera, which is often difficult to synchronise with the surgeon's movements. This article introduces a robotic system in which a rigid endoscope held by a robotic arm is controlled via the surgeon's eye movement, thus forgoing the need for a camera assistant. Gaze gestures detected via a series of eye movements are used to convey the surgeon's intention to initiate gaze contingent camera control. Hidden Markov Models (HMMs) are used for real-time gaze gesture recognition, allowing the robotic camera to pan, tilt, and zoom, whilst immune to aberrant or unintentional eye movements. A novel online calibration method for the gaze tracker is proposed, which overcomes calibration drift and simplifies its clinical application. This robotic system has been validated by comprehensive user trials and a detailed analysis performed on usability metrics to assess the performance of the system. The results demonstrate that the surgeons can perform their tasks quicker and more efficiently when compared to the use of a camera assistant or foot switches.

This paper introduces a gaze contingent controlled robotic arm for laparoscopic surgery, based on gaze gestures. The method offers a natural and seamless communication channel between the surgeon and the robotic laparoscope. It offers several advantages in terms of reducing on-screen clutter and efficiently conveying visual intention. The proposed hands-free system enables the surgeon to be part of the robot control feedback loop, allowing user-friendly camera panning and zooming. The proposed platform avoids the limitations of using dwell-time camera control in previous gaze contingent camera control methods. The system represents a true hands-free setup without the need of obtrusive sensors mounted on the surgeon or the use of a foot pedal. Hidden Markov Models (HMMs) were used for real-time gaze gesture recognition. This method was evaluated with a cohort of 11 subjects by using the proposed system to complete a modified upper gastrointestinal staging laparoscopy and biopsy task on a phantom box trainer, with results demonstrating the potential clinical value of the proposed system.

This paper presents dynamic characterization and control of an upper-limb rehabilitation machine aimed at improving robot performance in the interaction with the patient. An integrated approach between mechanics and control is the key issue of the paper for the development of a robotic machine with desirable dynamic properties. Robot inertial and acceleration properties are studied in the workspace via a graphical representation based on ellipses. Robot friction is experimentally retrieved by means of a parametric identification procedure. A current-based impedance control is developed in order to compensate for friction and enhance control performance in the interaction with the patient by means of force feedback, without increasing system inertia. To this end, servo-amplifier motor currents are monitored to provide force feedback in the interaction, thus avoiding the need for force sensors mounted at the robot end-effector. Current-based impedance control is implemented on the robot; experimental results in free space as well as in constrained space are provided.

The paper presents a novel control approach for robot motion and interaction control that is inspired by neuroscientific studies on the intermittency nature of motor control in humans. Robot motion is generated by dynamic sequences of elementary motion units (called submovements) that, on-line modulated, can achieve accurate motion or else force regulation. The submovement sequence generation is grounded on the adaptive behaviour of four oscillators. Control performance in free space and in interaction with a purely elastic environment can be managed by dynamically changing features of motion units in the current sequence. The theoretical formulation of the control strategy and the application to robot point-to-point motion in free and in constrained space are provided in this paper. Finally, a comparative analysis with a traditional PD control is carried out.

Introduction: Menetrier’s disease (MD) is a fundus and body gastritis frequently associated with hypoalbuminemia secondary to protein loss through the gastricmucosa. Clinical findings include vomiting, diarrhoea, abdominal pain, anorexia and peripheral oedema inmost cases. In one third of cases Cytomegalovirus (CMV) it is demonstrated having a central role in the pathogenesis and in childhood MD is usually a benign and self-limiting condition, lasting for a few weeks. Patients and methods: We present a 2 yrs old girl with important protein-loss admitted to our Unit; we describe diagnosis and management discussing the causative role of CMV in MD. Results: Two yrs-old girl with a few days history of diarrhoea, cough and fever especially during the night, important peripheral and periorbital oedemas presented at our Unit. Serological tests revealed anemia, iron deficiency, WBC elevated, hyponatremia, hypocalcemia, low level of thyroid hormones, hypoproteinemia, hypoalbuminemia and she was treated by human albumin. Antigliadin, antiendomysial and anti-tissue transglutaminase antibodies were negative. Urinary protein loss was excluded and her liver synthetic function was normal. Abdominal ultrasonography was negative for abdominal ascitic fluid. Nephrological cause was excluded and gastrointestinal causes were studied. Upper gastrointestinal endoscopy was performed and it showed mild multinodular duodenitis and a widely bleeding mucosa with large areas of erosions in the gastric body and fundus. Histologic examination confirmed a profound chronic active hypertrophic gastritis with intense regenerative epithelial hyperplasia. Tissue culture for Helicobacter Pylori and intranuclear CMV inclusion bodies were negative. Duodenal biopsy revealed normal mucosa and villous that excluded coeliac syndrome. An infectious cause is hypothised and serological tests for virus, bacteria and parasites revealed positive serum IgM antibodies against CMV; CMV DNAwas detected in blood through polymerase chain reaction (PCR). During her stay in hospital, shewas treatedwith PPI and another human albuminwas not necessary because of the improvement of her clinical condition. Next upper endoscopy after 20 days showed healing of duodenitis and an erythematous mucosa in the gastric body and fundus without erosions. She continued therapy with PPI and at clinical follow-up 4weeks later shewas free of symptomswith satisfactory weight gain and her haemoglobin, serum electrolytes and serum protein levels were normal, including IgA levels that exclude any Ig deficit. Conclusions: One of the major causes of MD in children is the CMV infection that should be suspected in every childwhopresents with protein-losing gastropathy. Upper endoscopy with histological examination and PCR level should be performed. Usually only supportive care is required, according to literature that describes MD in children as a transient and self-limiting condition. PO26

Taking inspiration from neurophysiological studies on synergies in the human grasping action, this paper tries to demonstrate that it is possible to find a general rule for performing a stable, human-like cylindrical grasp with a robotic hand. To this purpose, the theoretical formulation and the experimental validation of a reach-and-grasp algorithm for determining the optimal hand position and the optimal finger configuration for grasping a cylindrical object with known features are presented. The proposed algorithm is based on the minimization of an objective function expressed by the sum of the distances of the hand joints from the object surface. Algorithm effectiveness has preliminarily been tested by means of simulation trials. Experimental trials on a real arm-hand robotic system have then been carried out in order to validate the approach and evaluate algorithm performance.