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A Summary by Dr. Alexander Klemin of the Papers Presented Before the Fourteenth Meeting of the Institute held at Columbia University, New York, on January 29–31, 1946. AERODYNAMICS IN spite of increased wing loadings, the use of full span wing flaps has been delayed, because of inability to find a suitable aileron. The Development of a Lateral‐Control System for use with Large‐Span Flaps by I. L. Ashkenas (Northrop Aircraft), outlines the various steps in the aerodynamic development of a retractable aileron system well adapted to the full span flap and successfully employed on the Northrop P‐61. Included is a discussion of the basic data used, the design calculations made, and the effect of structural and mechanical considerations. Changes made as a result of preliminary flight tests are discussed and the final flight‐test results are presented. It is concluded that the use of this retractable aileron system has, in addition to the basic advantage of increased flap span, the following desirable control characteristics: (a) favourable yawing moments, (b) low wing‐torsional loads, (c) small pilot forces, even at high speed.

This paper gives a bibliographical review of the finite element methods (FEMs) applied to the analysis of ceramics and glass materials. The bibliography at the end of the paper contains references to papers, conference proceedings and theses/dissertations on the subject that were published between 1977‐1998. The following topics are included: ceramics – material and mechanical properties in general, ceramic coatings and joining problems, ceramic composites, ferrites, piezoceramics, ceramic tools and machining, material processing simulations, fracture mechanics and damage, applications of ceramic/composites in engineering; glass – material and mechanical properties in general, glass fiber composites, material processing simulations, fracture mechanics and damage, and applications of glasses in engineering.

Examines the fourteenth published year of the ITCRR. Runs the whole gamut of textile innovation, research and testing, some of which investigates hitherto untouched aspects. Subjects discussed include cotton fabric processing, asbestos substitutes, textile adjuncts to cardiovascular surgery, wet textile processes, hand evaluation, nanotechnology, thermoplastic composites, robotic ironing, protective clothing (agricultural and industrial), ecological aspects of fibre properties – to name but a few! There would appear to be no limit to the future potential for textile applications.

Nanopore-based molecular sensing and measurement, specifically DNA sequencing, is advancing at a fast pace. Some embodiments have matured from coarse particle counters to enabling full human genome assembly. This evolution has been powered not only by improvements in the sensors themselves, but also in the assisting microelectronic CMOS readout circuitry closely interfaced to them. In this light, this paper aims to review established and emerging nanopore-based sensing modalities considered for DNA sequencing and CMOS microelectronic methods currently being used.

Readout and amplifier circuits, which are potentially appropriate for conditioning and conversion of nanopore signals for downstream processing, are studied. Furthermore, arrayed CMOS readout implementations are focused on and the relevant status of the nanopore sensor technology is reviewed as well.

Ion channel nanopore devices have unique properties compared with other electrochemical cells. Currently biological nanopores are the only variants reported which can be used for actual DNA sequencing. The translocation rate of DNA through such pores, the current range at which these cells operate on and the cell capacitance effect, all impose the necessity of using low-noise circuits in the process of signal detection. The requirement of using in-pixel low-noise circuits in turn tends to impose challenges in the implementation of large size arrays.

The study presents an overview on the readout circuits used for signal acquisition in electrochemical cell arrays and investigates the specific requirements necessary for implementation of nanopore-type electrochemical cell amplifiers and their associated readout electronics.

This paper aims to propose a method for manufacturing multi-material monolithic structures with flexible materials to construct the elastic body by using a dual-nozzle three-dimensional printer to develop a piezoelectric (PZT)-driven micropositioning stage with three degrees of freedom (3-DOF) and flexure hinges.

Polylactic acid (PLA) and nylon were used for the lever structure’s frame and flexure hinge, respectively. Additionally, the stage consisted of three PZT actuators for fine movement in the nanometer scale in 3-DOF (x, y and θ-directions). For the design of the stage, the kinematic analysis model and the finite element method (FEM) analysis was undertaken for comparing between PLA with nylon (multi-material), PLA (single material) and aluminum (conventional-material). In addition, two verification experiments were implemented for the fabricated prototype stage. First, to evaluate various assessments (lever ratio, hysteresis, coupling error and resolution), a measurement is carried out using the three capacitive sensors. Then, a two-camera-vision measurement experiment was performed to verify the displacement and lever ratio over the full-scale working range of the fabricated positioning stage, and the results from the experimentation and the FEM analysis were compared.

The authors confirmed enhancements in the properties of the lever structure frame, which requires stiffness and of the hinge, which requires flexibility for elastic deformation. Comparing FEM analysis and experimental results, although the performance as shown by experimental results was lower: the maximum difference being 3.4% within the end-point working range; this difference was sufficient to be a plausible alternative for the aluminum-based stage.

Multi-material monolithic-structure fabrication has an effective advantage in improving the performance of the stage, by using a combination of materials capable of reinforcing the desired characteristics in the necessary parts. It was verified that the fabricated stage can substitute the aluminum-based stage and can achieve a higher performance than single-material stages. Thus, precise-positioning stages can be manufactured in many kinds of structures with various properties and contribute to weight reduction and low costs for application equipment.

Generally, the motion range of the micro scale operation is within several hundreds of microns, and the conventional joints cannot satisfy the requirements due to manufacturing and assembling errors, hysteresis and backlash in the joints. The paper aims to discuss these issues.

The following issues should be considered: a micromanipulation stage should be designed using a small-dimensional scale driven by the small size of piezoelectric actuator and the components can be replaced due to fatigue failure caused by repeated cyclic loading. This paper proposes a modular design of a flexure-based 2-DOF precision stage made using aluminum (T6-7075) material and Acrylonitrile Butadiene Styrene plastic material. The piezoelectric actuator is adopted to drive the stage for the fast response and large output force. To compensate the stroke of piezoelectric actuator, a bridge-type amplifier is designed with optimized structure.

The simulation results validate the advantages of modular positioning stage fabricated by two different materials.

The stage can be used in micro scale precision’s applications. If it will be used in nanoscale precision, then some sensors in nanoscale of measurement should be used.

The designed stage can be used in biomedical engineering, such as cell injection testing, etc.

The designed stage will be used in micro/nanoengineering field, such as micro/nanomanufacturing or assembly, manipulation of cell, etc., which will push forward high technology to a higher level.

Two kinds of materials have been selected to make the positioning stage, which are seldomly found in literature on compliant mechanism field. A modular design concept is proposed for the positioning stage design.

Examines the thirteenth published year of the ITCRR. Runs the whole gamut of textile innovation, research and testing, some of which investigates hitherto untouched aspects. Subjects discussed include cotton fabric processing, asbestos substitutes, textile adjuncts to cardiovascular surgery, wet textile processes, hand evaluation, nanotechnology, thermoplastic composites, robotic ironing, protective clothing (agricultural and industrial), ecological aspects of fibre properties – to name but a few! There would appear to be no limit to the future potential for textile applications.

The purpose of this study concerns numerical studies and experimental validation of the mechanical behavior of hybrid specimens. These kinds of composite specimens are made up of thin carbon and glass substrates on which some Macro Fiber Composite^® (MFC) piezoelectric patches are glued. A proper design and manufacturing of the hybrid specimens as well as testing activities have been performed. The research activity has been carried out under the FutureWings project, funded by the European Commission within the 7th Framework.

The paper describes the basic assumptions made to define specimen geometries and to carry out experimental tests. Finite element (FE) results and experimental data (laser technique measurements) have been compared: it shows very good agreement for the displacements’ distribution along the specimens.

Within the objectives of the project, the study of passive and active deformation characteristics of the hybrid composite material has provided reference technical data and has allowed for the correct adaptation of the FE models. More in particular, using the hybrid specimens, both the bending deformations and the torsion deformations have been studied.

The deformation capability of the hybrid specimens will be used in the development of prototypical three-dimensional structures, that, through the electrical control of the MFC patches, will be able to change the curvature of their cross section or will be able to change the angle of torsion along their longitudinal axis.

The design of nonstandard specimens and the tests executed represent a novelty in the field of structures using piezoelectric actuators. The numerical and experimental data of the present research constitute a small step forward in the field of smart materials technology.

WHEN John I. Snyder Jr. flew over from the United States he probably did not relish the Cassandra rôle into which circumstances had forced him. As president of U.S. Industries he gave one of the most depressing addresses of modern times. Since his firm is a large manufacturer of automation machines it was probably natural that he should say: ‘Automation is inevitable. Its use is rapidly increasing. Positive action by the makers of automation machines must be taken now to preserve the human values which could otherwise become cannon fodder of the automation barrage.’

EVER SINCE the invention of the gas turbine engine accurate measurement and indication of the working temperature of the turbine has been a prime requirement, in order to limit the environmental stresses of the very hot components in that area. It is now recognised by most authorities that a radiation pyrometer viewing the rotor blades offers considerable potential advantages as an engine temperature sensor over the use of a thermocouple array in the exhaust gas.