Soluciones para la medición de par y velocidad en bancos de ensayos de controladores de máquinas eléctricas

The continuous search for improvement in electromechanical developments requires a clear understanding of the torque measurement required in each application. The decisions made will have a profound impact on the quality and cost of the results. This article presents the principles normally used for sensing mechanical torque on a shaft and the reasons for the widespread use of strain gauges. The importance of differentiation between static and dynamic measurements and the current technologies used in each case are discussed. The relevant factors that define a transducer are described and a comparative analysis between them is carried out, to then examine the possible mounting methods, with their benefits and limitations. Finally, different low-cost solutions are proposed for the design of the torque and speed measurement section without sacrificing system performance, for different test benches for electrical machine controllers, including the necessary signal conditioning electronics. The article aims to be a tutorial compendium of topics to study to successfully implement a test bench without damaging the torque transducer or introducing measurement errors, since the information on these topics is scattered and it is difficult to access knowledge of the selection criteria and project procedures.La continua búsqueda de la mejora en los desarrollos electromecánicos impone una clara comprensión de la medición de par necesaria en cada aplicación. Las decisiones tomadas tendrán un profundo impacto en la calidad y el costo de los resultados. En este artículo se presentan los principios comúnmente empleados para el sensado de par mecánico en un eje y el porqué de la utilización extendida de las galgas extensiométricas. Se discuten la importancia en la diferenciación entre las mediciones estáticas y dinámicas, y las tecnologías actuales utilizadas en cada caso. Se describen los factores relevantes que definen a un transductor y se realiza un análisis comparativo entre ellos, para luego examinar los posibles métodos de montaje, con sus beneficios y limitaciones. Finalmente se proponen distintas soluciones de bajo costo para el diseño de la sección de medición de par y velocidad sin sacrificar el rendimiento del sistema, para diferentes bancos de ensayos para controladores de máquinas eléctricas, incluyendo la electrónica de acondicionamiento de señal necesaria. El articulo pretende ser un compendio tutorial de temas a estudiar para implementar con éxito un banco de ensayos sin dañar al transductor de par ni introducir errores de medición, ya que la información sobre esos temas está dispersa y es difícil acceder al conocimiento de los criterios de selección y procedimientos de proyecto

NASA patent abstracts bibliography: A continuing bibliography. Section 1: Abstracts (supplement 08)

This bibliography is issued in two sections; abstracts and indexes. The Abstract Section cites 180 patents and applications for patents introduced into the NASA scientific and technical information system during the period of July 1975 through December 1975. Each entry in the Abstract Section consists of a citation, an abstract, and in most cases, a key illustration selected from the patent or application for patent. The index Section contains entries for 2,905 patents and applications for patent citations covering the period May 1969 through December 1975. The Index Section contains five indexes -- subject, inventor, source, number and accession number

Cumulative index to NASA Tech Briefs, 1963-1967

Cumulative index to NASA survey on technology utilization of aerospace research outpu

Ninteenth Aerospace Mechanisms Symposium

The proceedings of the 19th Aerospace Mechanisms Symposium are reported. Technological areas covered include space lubrication, bearings, aerodynamic devices, spacecraft/Shuttle latches, deployment, positioning, and pointing. Devices for spacecraft docking and manipulator and teleoperator mechanisms are also described

Active magnetic bearing for ultra precision flexible electronics production system

Roll-to-roll printing on continuous plastic films could enable the production of flexible electronics at high speed and low cost, but the granularity of feature sizes is limited by the system accuracy. Technologies such as gravure printing and nanoimprint lithography demand a level of rotary motion precision that cannot be achieved with rolling element bearings. Manufacturing tolerances of the rotating parts, thermal drift and process forces in combination with structural compliance add up to additional error motions. In this master by research an active magnetic bearing (AMB) solution is designed for a new, super-sized roll-to-roll flexible electronics production machine, which was so far based on hydrostatic bearings. The magnetic bearing could actively compensate the accumulated synchronous error and maintain high accuracy under all conditions. However, the asynchronous error of a conventional AMB with the required size and power is a problem. In order to reduce the relatively high positioning uncertainty of active magnetic bearings an innovative radial position measurement based on linear, incremental encoders with optical conversion principle is proposed. A commercial encoder scanning head faces a round scale with concentric, coplanar lines on its face. By counting these lines the radial position can be measured. Because such a scale is not readily available, it is made by micro-machining. In experiments, different machining methods are compared. Then a magnetic bearing is built to demonstrate the efficacy of the proposed sensor. As a result, the best measurement noise is 3.5nm at 10kHz and a position uncertainty of approximately 0.25µm has been achieved for the magnetic bearing. These promising results are especially interesting for applications with high precision requirements at low speed of rotation

Particle detection experiment for Applications Technology Satellite 1 /ATS-1/ Final report

Applications technology satellite particle detection experiment for measuring energy spectra of earth magnetic fiel

Application of precision engineering for nanometre focussing of hard X-rays in synchrotron beam lines

This thesis was submitted for the degree of Master of Philosophy and awarded by Brunel University.Many modern synchrotron beamlines are able to focus X-rays to a few microns in size. Although the technology to achieve this is well established, performing routine experiments with such beams is still time consuming and requires careful set up. Furthermore there is a need to be able to carry out experiments using hard X-ray beams with even smaller beams of between 100nm and 10nm. There are focussing optics that are able to do this but integrating these optics into a stable and a usable experimental set up are challenging. Experiments can often take some hours and any change in position of the beam on the sample will adversely affect the quality of the results. Experiments will often require scanning of the beam across the sample and so mechanisms suitable for high resolution but stable scanning are required. Performing routine experiments with nanometre sized beams requires mechanical systems to be able to position the sample, focussing optics, detectors and diagnostics with significantly higher levels of stability and motion resolution than is required from so called micro focus beam lines. This dissertation critically reviews precision engineering and associated technologies that are relevant for building nano focus beamlines, and the following key issues are explored: • Long term position stability due to thermal effects • Short term position stability due to vibration • Position motion with nanometre incremental motion • Results of some tests are presented and recommendations given. Some test results are presented and guidance on designing nano focus beamlines presented.Diamond Light Sourc

NASA patent abstracts bibliography: A continuing bibliography. Section 1: Abstracts (supplement 06)

Patents and applications for patent introduced into the NASA scientific and technical information system are cited. Each entry consists of a citation, an abstract, and a key illustration selected from the patent or application for patent. The patent and application for patent citations are indexed according to subject, inventor, source, number, and accession number

Rogue Rotary - Modular Robotic Rotary Joint Design

This paper describes the design process from ideation to test validation for a singular robotic joint to be configured into a myriad of system level of robots

Estimating hand-grip forces causing Cumulative Trauma Disorder

Wearable sensors have garnered considerable interest because of their potential for various applications. However, much less has been studied about the Stretchsense pressure sensor characteristics and its workability for industrial application to prevent potential risk situations such as accidents and injuries. The proposed study helps investigate Stretchsense pressure sensors\u27 applicability for measuring hand-handle interface forces under static and dynamic conditions. The BendLabs sensors - a multi-axis, soft, flexible sensing system was attached to the wrist to evaluate the wrist angle deviations. In addition, the StretchSense stretch sensors were attached to the elbow joint to help estimate the elbow flexion/extension. The research tests and evaluates the real-time pressure distribution across the hand while performing given tasks and investigates the relationship between the wrist and elbow position and grip strength. The research provides objective means to assess the magnitudes of high pressures that may cause pressure-induced discomfort and pain, thereby increasing the hand\u27s stress. The experiment\u27s most significant benefit lies in its applicability to the actual tool handles outside the laboratory settings