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Jose Breñosa, Manuel Ferre
Haptics force feedback based on current control loop for remote manipulation

This paper presents the development of a force control loop in a teleoperation system with master and slave robotic devices. The force control based on current control loop has been applied to a teleoperation open platform consisting on electric master device, hydraulic slave robot and equipment for data acquisition and control programming. This force control loop is applied in each master joint using a custom designed electronic board with current sensors for closing the control loop. This board gives information about the current consumption and the direction of rotation of each motor drive. For maintaining the correct relationship between current and torque in each motor some experiments were performed to obtain the curves with an force/torque sensor from ATI. Finally, an inexpensive force control is obtained in the master device, providing an accurate haptic feedback for the operator.

Gianmichele Siano, Luigi Glielmo
Low-Cost Mobile Robotics Platform for Active Teaching

This paper describes a series of projects developed for a Real-Time Control course addressed to CS and EE students. The objective of this work is to show the realization of robotics experiments using low cost hardware. During the course the students are immersed in a realistic design environment, where they can strengthen the theoretical principles while improving their abilities to think, analyse, and solve problems using "learning by doing" approach.

Alberto Pretto, Giorgio Grisetti
Calibration and performance evaluation of low-cost IMUs

IMUs (Inertial Measurement Units) are extensively used in many robotics applications such as navigation and mapping tasks. In almost all these systems, inertial measurements are fused with data coming from other sensors (e.g., GPS sensors, range finders, cameras, . . . ). For better results, the IMU should be carefully calibrated, in order to minimize the propagation of systematic errors. But what happens if for brief periods data coming from the other sensors are missing? Can we trust the IMU in these cases? In this paper, we present a robust and simple method to calibrate an IMU without any external equipment. We then use the calibration results to analyze the behavior of two types of MEMS based IMUs employed as a single sensor in full 3D orientation and egomotion estimation tasks.

Stefano Scheggi, Gionata Salvietti
Haptic Guidance in Urban Search and Rescue Scenarios with Reduced Visibility

The use of robots in Urban Search and Rescue (USAR) has been widely studied in the last two decades. This scenario offers a unique opportunity to investigate Human Robot Interaction (HRI) in unstructured environments. In this paper, we present a possible paradigm of communication between human and robot based on haptic guidance. In particular, we developed a HRI framework in which the human agent is guided by a robot through a vibrating bracelet. The robot has on-board the necessary sensors to localize itself on a map or to build a new map in case of debris or collapsed walls. Moreover, the robot can localize the human position using a RGB-D camera (e.g., the kinect sensor) and generate commands for the haptic guidance. This approach could be particularly suited in case of reduced visibility.

M. Pisco, F. Galeotti, R. Parente, G. Quero, A. Iadicicco, M. Giordano, A. Cusano
Fiber Optic Sensing Probes using Self-assembly techniques

The “Lab on Fiber” technology has been recently proposed as a valuable route for the realization of novel and highly functionalized technological platforms completely integrated in a single optical fiber in communication and sensing applications. As a follow up of the proposed technological approach, here, we present recent results on the fabrication of metallo-dielectric structures on the optical fiber tip by using a selfassembly technique. The pursued approach basically consists in the preliminary preparation of a patterned polymeric film by the breath figure technique, directly on the optical fiber tip, and in the successive metal deposition by evaporation. The experimental results demonstrate the successful creation of a metallodielectric honeycomb pattern on the optical fiber tip. The sensing properties of the optical fiber probes have been successfully explored in terms of sensitivity to the surrounding refractive index changes demonstrating their potentialities for chemical and biological sensing applications. Finally, we report the preliminary results on the ongoing activities aimed to develop novel fabrication approaches of optical fiber sensing probes based on the assembly of microspheres into 2D colloidal crystals.

Carlo Edoardo Campanella, Lorenzo Mastronardi, Francesco De Leonardis, Vittorio M.N. Passaro
Pi-shifted fiber Bragg grating ring resonator as a splitting mode resonant sensor

In this paper we report on a splitting mode resonant sensor based on a ring cavity formed by closing on itself a pi-shifted fiber Bragg grating. In particular, this cavity allows to obtain a spectral response characterized by a splitting mode structure, composed by both symmetric and antisymmetric resonances. The modal splitting occurs very close to the Bragg wavelength, where the pi-shifted fiber Bragg grating shows its transmission resonant maximum. In this region, for particular index modulation depths of the fiber Bragg grating, the linewidth of the two antysimmetrical modes suffers of an opposite behaviour because the symmetrical resonance linewidth is enlarged while the antisymmetrical resonance linewidth is reduced. Thus, we demonstrate that, near the Bragg wavelength, the splitting magnitude only depends on the index modulation depth of the fiber Bragg grating and it is independent from the device length. In this way, being the splitting magnitude insensitive to the length variations associated to any external perturbation, the proposed device can be used for those sensing applications requiring a sensing mechanism immune to the environmental noise sources.

Elena Pettinelli, Elisabetta Mattei, Barbara Cosciotti, Federico di Paolo, Sebastian Emauel Lauro
Laboratory and field Ground Penetrating Radar measurements for buried weapons detection

In this work we present the results obtained in two different experiments aimed at evaluating the capability of Ground Penetrating Radar to detect buried metal weapons. The first experiment was conducted acquiring radar data on a layer of synthetic sand in which a metal gun was hidden at shallow depth. The second experiment was conducted in the field, collecting radar data in an area where four different objects were buried (at about 30cm) in sandy volcanic soil. The radar survey was performed for different soil water contents (dry and wet conditions). The results show how the capability to detect the targets and define their depth and shape is strongly dependent on the target depth and orientation with respect to the antenna electric field, as well as to the host material dielectric properties.

Stefano Di Pasquale, Sabino Giarnetti, Fabio Leccese, Daniele Trinca, Maurizio Caciotta
A New Platform for High Accuracy Power Quality Measurements: the Forensic Point of View

A new platform for Power Quality measurement based on PIC 32 family microcontroller has been realized and tested. The board is able to determine the frequency of the mains implementing the Curve Fitting Algorithm and is able to detect punctual events as short interruptions. The device allows performing high accuracy measurements and is a good candidate as platform to use in civil suit in the subject of Power Quality analysis.

Giuseppe Schirripa Spagnolo, Lorenzo Cozzella, Maurizio Caciotta, Roberto Colasanti, Gianluca Ferrari
Analogue Fingerprinting for painting authentication

Artwork counterfeiting is a wide problem in the art market, both for private subject and museums. In this paper an innovative system based on smartphone acquisition and mobile application is depicted to verify artwork authenticity based on random intrinsic object characteristics. This approach is based on biometry paradigm (analogue fingerprinting). The paper present a stand-alone solution, and an internet-based one, necessary for granting security verification also in case of problem with the used RFID tag. The proposed method uses an RFID Tag and a 2D barcode, in conjunction with an Internet-based Authentication Archive.

Giuseppe Schirripa Spagnolo, Donato Papalillo, Lorenzo Cozzella, Fabio Leccese
Forensic Metrology: Uncertainty of Measurements in Forensic Analysis

In many cases, forensic scientists rely on measurements as a basis for their opinions. In the past, forensic scientists, testifying about such measurements, have often presented the court with a single point value. The problem is that there is an unavoidable and an inherent element of uncertainty in every measurement. The metrology has developed several methods of quantifying a measurement’s margin of error or uncertainty. By using these methods, the testifying expert can put the trier in a much better position to determine the appropriate evidentiary weight of the measurement. The purpose of this paper is to describe the problem of uncertainty in forensic science and in particular uncertainty in measurements by forensic scientists. In this paper, the problem of uncertainty is described in a relatively non-technical way. In other words, the discussion will focus on concepts rather than on analytical analysis.

Page 456 of 977 Results 4551 - 4560 of 9762