Modular Sensor Research Articles

Using unmanned underwater vehicles as research platforms in coastal ocean studies

The advantages of using unmanned underwater vehicles in coastal ocean studies are emphasized. Two types of representative vehicles, remotely operated vehicle (ROV) and autonomous underwater vehicle (AUV) from University of South Florida, are discussed. Two individual modular sensor packages designed and tested for these platforms and field measurement results are also presented. The bottom classification and albedo package, BCAP, provides fast and accurate estimates of bottom albedos, along with other parameters such as in-water remotes sensing reflectance. The real-time ocean bottom optical topographer, ROBOT, reveals high-resolution 3-dimentional bottom topography for target identification. Field data and results from recent Coastal Benthic Optical Properties field campaign, 1999 and 2000, are presented. Advantages and limitations of these vehicles and applications of modular sensor packages are compared and discussed.

A Modular Electrochemical Sensor for Saccharides.

A modular electrochemical saccharide sensor using ferrocene has been prepared which contains two boronic acid receptor groups and hexamethylene linker.

Synthesis and Characterization of a Siderophore‐based Luminescent Sensor for Molybdate

AbstractBy connecting a bidentate siderophore to a luminescent tris(2, 2′‐bipyridyl)ruthenium(II) unit, a modular sensor reagent has been synthesised and characterised which selectively signals the presence of molybdate in solution through a decrease in emission intensity.

Complementary analytical measurements based upon gas chromatography-mass spectrometry, sensor system and human sensory panel: a case study dealing with packaging materials

In co-operation with packaging material suppliers and a food manufacturer the quality of different kinds of wrapping foils for chocolate bars was investigated by using the hybrid Modular Sensor System (MOSES II). To check the reproducibility and to deduce quantitative predictions a gas chromatograph-mass spectrometer (GC/MS)-unit connected to a headspace-sampler (HSS) was used as a well established analytical reference instrumentation. All analysed samples were also qualified by a human sensory panel according to the sniff-test. The different packaging material species could be distinguished in a principal component analysis (PCA). With the aid of a principal component regression (PCR) a correlation between human and technical odour perception was carried out. The odour prediction of MOSES II was very satisfying particularly if compared to the human sensory assessments. Additionally, in order to follow the sensor fluctuations the sensor responses upon exposure to a standard sample have been monitored for 5 months. The results of these measurements and the investigations of four different MOSES II units demonstrated the long-term stability of the individual sensors and the high reproducibility from system to system.

Selective signalling of molybdate by a siderophore derivative†

By connecting the siderophore aminochelin of Azotobacter vinelandii to a highly fluorescent tris(2,2′-bipyridyl)ruthenium(II)-type chromophore, a new modular sensor reagent has been synthesised and characterised, which selectively signals the presence of molybdate in solution through luminescence quenching.

Electronic nose: a useful tool for monitoring environmental contamination

The advances in the technology of multisensor arrays and neural computation have allowed the development of “electronic noses”, which has enabled the discrimination of compounds by their odours and consequently, has played a fundamental role in the environmental monitoring. An electronic nose MOSES II (MOdular SEnsor System) with two arrays of eight (tin oxide and quartz microblance) sensors, each one manufactured by Lennartz Electronic/MoTech, was employed in this work. The aim of this research was to discriminate the following factors by odours: (a) small concentrations (ppm) of lindane and nitrobenzene in water, (b) dry solid insecticides (synthetic pyrethroids) such as permethrin, deltamethrin and cypermethrin, (c) mixtures of different quantities of cypermethrin in an inert substance, and (d) solutions of these pyrethroids in an appropriate organic solvent. Contaminating residues of insecticides (lindane and syntethic pyrethroids) and products from the leather manufacture (phenols, nitrobenzene, anilines) are often offloaded into streams or rivers — despite the prohibition regulations — in heedless disregard of the danger they present to the health of the population and the survival of fish and flora.

Optimised sensor arrays with chromatographic preseparation: characterisation of alcoholic beverages

High concentrations of alcohol increase the difficulties in identifying different alcoholic beverages with sensor arrays, because odour-relevant species usually occur at much lower concentrations. In this study, the characterisation of different beer brands was possible with a modular sensor system (MOSES II). The latter was combined with a gas-chromatographic column thus enabling preseparation. The classification of beer brands was independent of the ethanol content. Fermentation by-products of the beer could also be detected and classified. In addition, different types of white wine and one red wine were investigated by the same method.

Internet-based distributed measurement and control applications

The NIST DMC (distributed measurement-and-control) demonstration project that has been described spans all levels of the DMC system. This multilevel data communication capability is a viable one as a result of standardized networks, protocols, and transducer interfaces. Common Internet-based software technology was used to provide the ease of data migration between the various communication pathways. Standard and de facto software languages such as C and Java were used with off-the-shelf development tools to implement the embedded network node applications and the web-based application, respectively. Internet-based TCP/IP protocols and Ethernet technology were used to design the networking infrastructure. The distributed measurement and control concept with networking sensors and actuators should work quite well with advanced system design, particularly where sensor-based monitoring and control applications are important. Taking this approach in system design can reduce the total life-cycle cost of the system by use of modular sensor system design and commercially available smart transducers with standardized interfaces, and easy maintenance and upgrade via simple plug-and-play sensor and actuator components. In addition, using standardized components and interfaces will certainly reduce interoperability problems.

Hybrid modular sensor systems: A new generation of electronic noses

Hybrid modular sensor systems: A new generation of electronic noses

Odours and flavours identified with hybrid modular sensor systems

Hybrid sensor systems contain different types of chemical sensors whereby each type (transducer principle) contains an array of individual sensors. This leads to a large flexibility in the choice of transducers and sensor materials with the general aim of optimising the analytical performance of the total system. This concept makes it possible to optimise the quantitative analysis of mixtures of known gases as it will be demonstrated for mixtures of volatile organic compounds (VOCs). Alternatively this makes it possible to optimise the system for characterising odours and flavours. This will be demonstrated for different plastic as well as textile materials used in car industries and for different products of food industries, i.e. coffees, tobaccos, whiskeys, and olive oils. In our modular sensor systems we used arrays of different semiconductor gas sensors (based on metal oxides), of polymer coated quartz microbalance (QMB) sensors, of calorimetric sensors and of electrochemical sensors, with an option to add metal oxide semiconductor field effect transistor (MOSFET) sensors. These arrays are arranged as separate components in a modular sensor system ‘MOSES’. For the qualitative discrimination of different odour samples a headspace-autosampler was added and transient sensor signals were monitored. The use of different transducer principles is shown to be essential for an unequivocal identification of odours and flavours.

Error analysis of an acoustic current meter

Accuracies of the benthic acoustic stress sensor (BASS) and the proposed modular acoustic velocity sensor (MAVS) are evaluated. A simple model of the hydrodynamic sources of error for acoustic current meters is presented and compared with the measured performance of BASS in a tow-tank and in field deployments. The sources of error addressed include those due to ideal flow around the sensor cage, wake effects from the support structure and transducers, vortex shedding from the cage, and electronic zero-point offsets. Electronic error dominates at velocities less than 5-10 cm/s, while flow disturbance dominates at higher speeds. >

A Modular Approach to Sensor Integration in Robotic Assembly

We describe the use of functional abstraction for the design of modular sensor integration systems that provide task supervisors with the sensor information required to perform robotic assembly tasks or subtasks. We offer a versatile approach to high-performance sensor integration. This is consistent with the low-cost robotic assembly cells that will be needed to make automated assembly attractive to a wider sector of manufacturing industry.

Sensor interfaces for intelligent measurement

Varied changes in manufacturing methods and the increasing degree of automation have recently been the dominant factor in the demands imposed upon manufacturing integrated measurement techniques. For this special area, decentrally structured measuring systems with distributed intelligence and sensor functions can be used over an increasingly wide range of applications. For basic sensors to measure physical quantities as force, pressure, temperature, length, etc, a modular sensor system with an integrated microprocessor for signal converting and processing, as well as for building up standard interfaces at the output side, will be described. There are interface problems specific to the application of simple digitised standard measurement devices to microprocessors or personal computers. For this problem a logical interface shall be described in which all data have a fixed format and freely programmable contents. Finally, a system concept shall show how measurement technique is to include in computer-integrated manufacturing systems (CIM).