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Interest in autonomous underwater vehicles is constantly increasing following the emerging needs of underwater exploration and military purposes. Thus, several new propulsion mechanisms are studied and developed. Fish swimming is a promising source of inspiration because they outperform conventional propellers in terms of energy efficiency and maneuvrability. Their advantages are not only due to the streamlined shape and their low-drag skin but also, above all, due to the particular fin motion, which makes thrust generation possible with small energy dissipation. This paper analyses the motion of batoid fishes that are considered highly efficient by biologists. Their motion is reproduced by different linkage mechanisms optimized to fit underwater robots. A bioinspired robot mimicking cownose ray locomotion is, then, designed and built. Numerical analysis of its dynamics allows us to measure the size of actuators and to estimate the robot behavior. Finally, the control algorithm that maintains the mechanism synchronization according to different strategies is described and some experimental results are presented.

Although plants are usually seen as static organisms, they exhibit a wide range of movements that only in recent years have been considered as a source of inspiration for robots. The motion of roots is one of the most interesting, because they are extraordinary diggers, able to navigate in unstructured environments, finding their way around obstacles. Moreover, root growth is featured by high energy efficiency because they penetrate the soil adding new material at their tip, without moving the already grown part, preventing friction from dissipating energy and reducing the inertia. A robot inspired to roots’ growth could be employed in search and rescue operations or in environmental monitoring. In this work the design of a soft robot inspired to root’s growth is presented. The body of the robot consists of a cylindrical plastic membrane folded inside itself. When air is blown from the base, the body of the robot is inflated, and its tip is everted increasing its length. On the external surface some Velcro stripes are mounted, which keep the membrane folded. Inside the tip a head is mounted, where the mechanism controlling the direction of growth is placed. It consists of a housing for some balloons, which can be inflated selectively, and their expansion exerts a pressure on the external surface able to open the Velcro stripes. The direction of growth is controlled by selecting which balloon to inflate. The robot has been built and a kinematic model of its motion in the plane has been developed and compared with experimental results.

One field in which nature outperforms current technology is fish swimming, because its efficiency, manoeuvrability and noise are far better than those of typical ship propellers. These advantages are not only due to the streamlined shape and the low-drag skin, but also and above all to the propulsion mechanism, which makes thrust generation possible with small energy dissipation in vortices. Nowadays the interest in autonomous underwater vehicles is in constant increase following the emerging needs of underwater mining and fish farming. Batoid fishes produce thrust with their pectoral fins, they essentially produce a wave travelling in the direction opposite to their motion, pushing water backwards and gaining thrust as a consequence of momentum conservation. The motion of the fin has been studied and reproduced with a series of articulated mechanisms. In this work the optimization of the mechanism’s geometry is described and the experimental results on the reconstructed fin are presented. Moreover, a bioinspired robot mimicking cownose ray locomotion has been designed and built. In this paper the functioning of this robot is shown.

Roots are extraordinary diggers because they penetrate the soil adding new material on their tip without moving the already grown part, preventing friction from dissipating too much energy and minimising inertial forces during motion. A robot exploiting this principle can assist operations of search and rescue digging in mud or snow to find people in danger. In this work a soft pneumatic robot inspired to roots’ growth is presented. The body of the robot consists of a cylindric plastic membrane folded inside out; one extremity is kept fixed to the base, whereas the other one is folded inside itself. When air is blown from the base, the body of the robot is inflated, and its tip is everted increasing its length. Inside the tip a head is mounted, where the mechanism controlling the direction of growth is placed. On the external surface of the membrane some hooks are mounted, and tensioned wires connects them longitudinally while they are folded before being everted. These wires are cut when they pass next to the head allowing the robot to unfold; since series of hooks are distributed radially on the body of the robot, the direction of growth is controlled by selecting which wires are to be cut. On the head of the robot can be mounted an infrared sensor or a video-camera needed for the specific application.

Professional players claim that stringed musical instruments exhibit better acoustic behaviour if they are frequently played. Although in literature there is no clear relationship between these phenomena, this work aims to develop a device capable of “making a violin sound” autonomously, so that it can always be kept in optimal conditions. The paper shows the design aspects of the magnetostrictive actuator, its operating principle, the prototype development and the experimental characterization. The prototype is then mounted on a new violin, simulating its continuous use for a week. During the test the acoustic measurements showed a large change in the acoustic response of the instrument, thus demonstrating the effectiveness of the magnetostrictive actuator in the training of a stringed instrument.

Urinary Tract Infections (UTIs) are a severe public health problem, accounting for more than eight million visits to health care providers each year. High recurrence rates and increasing antimicrobial resistance among uropathogens threaten to greatly increase the economic burden of these infections. Normally, UTIs are diagnosed by traditional methods, based on cultivation of bacteria on Petri dishes, followed by a visual evaluation by human experts. The need of achieving faster and more accurate results, in order to set a targeted and sudden therapy, motivates the design of an automatic solution in place of the standard procedure. In this paper, we propose an algorithm that combines a “bag–of–words” approach with machine learning techniques to recognize infected plates and provide the automatic classification of the bacterial species. Preliminary experimental results are promising and motivate the introduction of a visual word dictionary with respect to using low level visual features.

A new CMS tracker is scheduled to become operational for the LHC Phase 2 upgrade in the early 2020's. tkLayout is a software package developed to create 3d models for the design of the CMS tracker and to evaluate its fundamental performance figures. The new tracker will have to cope with much higher luminosity conditions, resulting in increased track density, harsher radiation exposure and, especially, much higher data acquisition bandwidth, such that equipping the tracker with triggering capabilities is envisaged. The design of an innovative detector involves deciding on an architecture offering the best trade-off among many figures of merit, such as tracking resolution, power dissipation, bandwidth, cost and so on. Quantitatively evaluating these figures of merit as early as possible in the design phase is of capital importance and it is best done with the aid of software models. tkLayout is a flexible modeling tool: new performance estimates and support for different detector geometries can be quickly added, thanks to its modular structure. Besides, the software executes very quickly (about two minutes), so that many possible architectural variations can be rapidly modeled and compared, to help in the choice of a viable detector layout and then to optimize it. A tracker geometry is generated from simple configuration files, defining the module types, layout and materials. Support structures are automatically added and services routed to provide a realistic tracker description. The tracker geometries thus generated can be exported to the standard CMS simulation framework (CMSSW) for full Monte Carlo studies. tkLayout has proven essential in giving guidance to CMS in studying different detector layouts and exploring the feasibility of innovative solutions for tracking detectors, in terms of design, performance and projected costs. This tool has been one of the keys to making important design decisions for over five years now and has also enabled project engineers and simulation experts to focus their efforts on other important or specific issues. Even if tkLayout was designed for the CMS tracker upgrade project, its flexibility makes it experiment-agnostic, so that it could be easily adapted to model other tracking detectors. The technology behind tkLayout is presented, as well as some of the results obtained in the context of the CMS silicon tracker design studies.

The dragonfly’s ability of gliding and performing dexterous maneuvers during flight attracts the interest of scientists and engineers who aim at replicating its performances in micro air vehicles. The great efficiency of its flight is achieved thanks to the vortices generated by wing movements and thanks to the corrugations on their surfaces. The high freedom of control of each wing has been proved to be the secret behind the dragonfly capability to carry out incredible flight manoeuvers. The study presented in this paper analyzes two of the most common flight regimes of the dragonfly. Firstly, some CFD simulations of gliding are performed and drag and lift coefficients have been calculated, showing a good match with experimental data found in literature. Then, hovering has been studied using a methodology inspired to the Blade Element Momentum (BEM) theory, which is usually applied in the context of wind turbines design. The lift force calculated with this simulation corresponds to the weight of dragonfly, suggesting the correctness of this analysis.

This paper presents a control method for scaled teleoperation where the slave workspace is larger than the master one. In future, the results of this paper will be employed in a joystick for excavator controlling. The whole system is made up of a haptic master device and a virtual slave one. The master device consists in an 1 D.o.F. joystick provided with a shaft mounted torque sensor. The scaled force the human operator exerts on the master device commands the slave device input force. Conversely, the master position follows the slave position. In this way, a realistic feeling of the remote environment is provided. A virtual damping force proportional to the slave speed is introduced into the slave control in order to improve the teleoperation. The theoretical approach has been validated with experimental results.

In this paper we describe the feasibility analysis and the prototyping of a 3-D optical measurement system. The system is a catadioptric one, consisting of a combination of refracting (camera lens) and reflecting (mirror) elements. Employing mirrors in order to increase efficiency in camera CCD exploitation, is the innovative idea we propose. An accurate study of camera calibration and distortion correction algorithm have been carried out. Moreover, we propose a closed-form solution for camera calibration. This method has been integrated with the Newton-Raphson algorithm. Eventually, experimental results are given.

This paper presents the design of a PID controller for a flexible planar manipulator, based on a very accurate dynamic model of the system. The model is employed to test a classical PID regulator in simulation, in order to be able to control a flexible five-bar closed-chain planar manipulator. The chosen PID controller is described, and the most significant simulation results are presented and discussed.