Special Issue "Instrumentation, Signal Treatment and Uncertainty Estimation in Sensors"

Guest Editor
Prof. Dr. Jesus de Vicente
Universidad Politecnica de Madrid, ETSI Industriales, Calle Jose Gutierrez Abascal 2, 28006 Madrid, Spain
E-Mail:
Interests: nanometrology; uncertainty estimation; confocal microscopy; laser interferometry; coordinate metrology at the nanoscale

Guest Editor
Prof. Dr. Wilmar Hernandez
Department of Circuits and Systems, E.U.I.T. de Telecomunicacion, Universidad Politecnica de Madrid, Campus Sur UPM, Ctra. Valencia km7, 28031 Madrid, Spain
Website: http://www.euitt.upm.es/17.Perso/directorio.php?coddep=ICS
E-Mail:
Interests: intelligent sensors; mechanical sensors; electronics; instrumentation; optimal signal processing; robust and optimal control

Submission

• sensors
• actuators
• automotive sensors
• intelligent sensors
• intelligent materials,
• electronic instrumentation for sensors
• robust and optimal control and signal processing applied to improve the performance of sensor systems
• calibration
• measurement uncertainty estimation
• mathematical modelling of sensors

Type of Paper: Article
Title: A New Myohaptic Instrument to Assess Wrist Motion Dynamically
Authors: G. Grimaldi, P. Lammertse, N. Van Den Braber and M. Manto; E-Mails: mmanto@ulb.ac.be, giulianagrim@yahoo.it
Abstract: Assessment of joint properties remains a challenge. Several tools have been developed, but so far most of these tools have remained confined to laboratories, with a lack of standardization. We report on a new device which combines the use of electromyographic sensors (EMG) with the haptic technology for the dynamic investigation of wrist properties. The instrument is composed of a drivetrain, a haptic controller and a signal acquisition unit. Angular accuracy is 0.35 deg, nominal torque is 6 Nm, maximal rotation velocity is 2000 degrees/sec, with a range of motion of -60 to +60 degrees. The inertia of the motor and handgrip is 0.004 kg x m². This is the first instrument allowing the dynamic characterization of wrist properties, including under the condition of artificial damping.

Type of Paper: Review
Title: Measurement Uncertainty Estimation in Amperometric Sensors
Author: Ivo Leito
Affiliation: Institute of Chemistry, University of Tartu; E-mail: ivo.leito@ut.ee
Abstract: This tutorial focuses on measurement uncertainty estimation in amperometric sensors (both for liquid and gas-phase measurements). The main uncertainty sources are reviewed and linked to the principles of operation of the sensors and properties of the measured samples. The approximate magnitudes of the uncertainty sources are assessed and discussed in connection with sensor type, analyte properties and measurement conditions. As a result, a generic approach for uncertainty estimation in amperometric sensors is presented and its application is illustrated by examples.

Type of Paper: Article
Title: Biosensors for Environmental Applications
Authors: Andrea Medeiros Salgado et al.
Affiliation: Department Bioquemistry Engineering, Universidade Federal do Rio de Janeiro- Gávea, Rio de Janeiro - RJ, 22631-180, Brazil; E-Mail: andrea@eq.ufrj.br
Abstract: Biosensors are detection devices that incorporate either an live organism or derivated products of biological systems and a transducer that provides indication, signal or any other recognition form of a specific substance in the environment. The biosensors development is a multidisciplinary area, and these instruments can be applied in environmental monitoring. Although the use of biosensors in environmental monitoring are not so widespread as in the medical and clinical areas, investments and applications in the environmental context have been growing due to their characteristics: provides results in real time, specificity, portability, low cost and less toxic waste generation per analysis. Some examples of biosensors in advanced stage of development, which have been applied to real samples, as well as of commercial devices, are given. The aim of this article is to reflect the advances and describes the trends on biosensors for environmental applications.

Type of Paper: Article
Title: 3D Optical Laser Triangulation Sensor and Six Axes Anthropomorphic Robot Manipulator Modelling for the Measurement of Complex Geometry Parts
Authors: Francisco Javier Brosed, Jorge Santolaria and Juan José Aguilar
Affiliation: Design and Manufacturing Engineering Department, University of Zaragoza. María de Luna, 3; E-50018 – Zaragoza (SPAIN) E-Mail: jsmazo@unizar.es (J.S.)
Abstract: A 3D Optical laser triangulation sensor and six axis manipulator mathematical modelling for the measurement of complex geometry parts will be show in the article. Integrated system model covers the optical sensor, the geometry of the manipulator and the relative positions of the components along the measurement process. The article outlines the basic parameters of the model and the method used to obtain the values of these parameters. Plane surfaces with holes and termination of tubes placed in different orientations will be measured and the accuracy of the integrated system (sensor & robot) will be presented.

Type of Paper: Article
Title: Field Evaluation of Polymer Capacitive Humidity Sensors for Bowen Ratio Energy Balance Flux Measurements
Author: Michael J. Savage
Affiliation: Agrometeorology School of Environmental Sciences, Soil-Plant-Atmosphere Continuum Research Unit, University of KwaZulu-Natal, Pietermaritzburg, 3209 South Africa; E-Mail: savage@ukzn.ac.za
Abstract: In order to obtain reliable and reasonably accurate estimates of sensible heat and latent energy fluxes using the Bowen ratio energy balance (BREB) method, use of a commercial combination thin-film polymer capacitive relative humidity and adjacent temperature sensor instrument, for long-term and unattended measurement of water vapour pressure profile differences, as opposed to a cooled dewpoint mirror hygrometer often used with such systems, was investigated. The main disadvantage of a combination capacitive humidity instrument is that two measurements are required for estimation of air stream water vapour pressure as opposed to one measurement for a dewpoint hygrometer. In a laboratory experiment using an automated procedure, water vapour pressure differences generated using a reference dewpoint generator were measured using a dewpoint hygrometer and a combination capacitive humidity instrument. These results show that, potentially, an inexpensive combination capacitive humidity instrument, or more likely a slightly more expensive model, could substitute for the more expensive dewpoint hygrometer. In a field study, the water vapour pressure measurement noise for two different models of a combination capacitive humidity instrument was greater than that for a dewpoint hygrometer. The average water vapour pressure profile difference for the more expensive combination capacitive humidity instrument tested was highly correlated with that from the dewpoint hygrometer (slope of 0.9334, correlation coefficient r of 0.9949). The more expensive of the two capacitive humidity instruments used was not as accurate, compared to the dewpoint hygrometer, but its resolution magnitude for measurement of the profile differences was less than the minimum of 0.01 kPa required for BREB measurements when averaged over 20 min. A comparison of the two different combination capacitive humidity models used for measurement of the profile water vapour pressure differences yielded a slope of 1.0236 (r = 0.9978). However, the less expensive model exhibited a greater variation in measured water vapour pressure mainly as a consequence of greater variation in its temperature measurements. A field comparison, in a mesic grassland, between 20-min BREB sensible heat flux obtained using the more expensive model capacitive humidity instrument and a dewpoint hygrometer yielded a slope of 1.0178 (r = 0.9941). BREB sensible heat flux measured using the combination capacitive humidity instrument was reasonably well correlated with fluxes obtained using a surface-layer scintillometer and eddy covariance (slope of 0.806 and 0.834 respectively and r = 0.8849 and 0.8818). This reasonable agreement shows that this capacitive humidity instrument, or one with similar relative humidity and temperature accuracy and sensor time responses, would be an adequate and less expensive substitute for the dewpoint hygrometer. Furthermore, this combination capacitive humidity instrument requires no servicing compared to a dewpoint hygrometer which requires a bias adjustment and mirror cleaning each week. These findings make unattended BREB measurements of evaporation cheaper and more reliable with the system easier to assemble and service and with reduced power.

Type of Paper: Article
Title: Performance Evaluation of Triangulation Based Range Sensors
Authors: Gabriele Guidi, Michele Russo, Grazia Magrassi, Monica Bordegoni
Affiliation: Department of Industrial Design, Art, Communication and Fashion (INDACO) - Politecnico di Milano, Via Durando 38/A, 20158, Milan, Italy; Department of Mechanical Engineering - Politecnico di Milano, Via La Masa 34, 20156, Milan, Italy; Email: gabriele.guidi@polimi.it (G.G.)
Abstract: The performances of 2D digital imaging systems depend on several factors related with both optical and electronic processing. These concepts originated standards, conceived for photographic equipment and bi-dimensional scanning systems, for calculating different parameters such as resolution, noise or dynamic range. On the other hand no standard test protocols currently exist for evaluating the corresponding performances of 3D imaging systems such as laser scanners or pattern projection range cameras. This paper is focused on investigating an experimental process that allows to evaluate some critical parameters of a 3D equipment, extending concepts defined by the ISO standards to the 3D domain. The experimental core of this paper is focused on characterizing different range sensors through the extraction of resolution, accuracy and uncertainly parameters from 3D acquisitions of specifically designed target objects whose geometrical characteristics are known in advance. The general aim of this contribution is to suggest an easy characterization process for generating a reliable comparison between different range sensors performances’ or check if the performances of a particular equipment are compliant with the expected ones.
Keywords: metrological characterization, 3D measurement, laser scanner, pattern projection, resolution, uncertainty, accuracy