Measuring Torque and Temperature in a Rotating Shaft Using Commercial SAW Sensors

Real-time monitoring of torque in a rotating shaft is not easy to implement with technologies such as optic fiber sensors or strain gages. Surface acoustic wave (SAW) sensors are wireless and passive and can be used to monitor strain in moving parts. Commercial solutions (sensors, antennas and interrogation unit) can easily be purchased from some companies; however, they are not customized and may not meet the specificity of the measurements. In order to evaluate the adequacy of commercial off-the-shelf (COTS) solutions, temperature and strain sensors fabricated by SENSeOR (Besançon, France) were mounted on a load cell. The sensors were calibrated using a thermal chamber and a universal testing machine. The load cell was then assembled together with a steel shaft that rotated at different speeds inside an oven. The commercial antennas were replaced with an RF (radio frequency) coupler and the sensors were interrogated with the commercial interrogation unit. The influence of rotation in the accuracy on the measurements, as well as the adequacy of the sensors structure, was evaluated. It can be concluded that SAW sensors can be used to measure temperature or torque in a rotating environment; however, some customization of the components is required in order to overcome the limitations posed by COTS sensing solutions

Improved performance of motor-drive systems by SAW shaft torque feedback

The paper describes the application of a non-contact, high bandwidth, low cost, SAW-based torque measuring system for improving the dynamic performance of industrial process motor-drive systems. Background to the SAW technology and its motor integration is discussed and a resonance ratio control (RRC) technique for the coordinated motion control of multi-inertia mechanical systems, based on the measurement of shaft torque via a SAW-based torque sensor is proposed. Furthermore, a new controller structure, RRC plus disturbance feedback is proposed, which enables the controller to be designed to independently satisfy tracking and regulation performance. A tuning method for the RRC structure is given based on the ITAE index, normalized as a function of the mechanical parameters enabling a direct performance comparison between a basic proportional and integral (PI) controller. The use of a reduced-order state observer is presented to provide a dynamic estimate of the load-side disturbance torque for a multi-inertia mechanical system, with an appraisal of the composite closed-loop dynamics. The control structures are experimentally validated and demonstrate significant improvement in dynamic tracking performance, whilst additionally rejecting periodic load side disturbances, a feature previously unrealisable except by other, high-gain control schemes that impose small stability margins

Multi-Function Tribometer Design

ME450 Capstone Design and Manufacturing Experience: Winter 2010Friction and wear properties of many material combinations are becoming increasingly important as engineers look to create more durable and reduced-friction materials. Currently, there is no tribometer which can measure real world complex 2D wear patterns at speeds required by our sponsor. Because of this, our team has been asked to design a tribometer which will measure friction and wear in complex two-dimensional wear patterns to better model and test real world applications. Key design characteristics will include both closed-loop environmental control and closed-loop normal force application. A successful prototype must have each of the aforementioned functionalities among others.http://deepblue.lib.umich.edu/bitstream/2027.42/109387/1/me450w10project5_report.pdfhttp://deepblue.lib.umich.edu/bitstream/2027.42/109387/2/me450w10project5_photo.jp

Use of triple beam resonant gauges in torque measurement transfer standard

This thesis was submitted for the degree of Doctor of Philosophy and awarded by Brunel University.A new torque transfer standard using metallic TBTF resonant sensor was developed to overcome the overload capability problem which occurs with conventional metallic resistance strain gauges. Previous research work, however, has shown that the first prototype of the metallic TBTF resonant sensor was not suitable for use in a torque transfer standard due to its size and subsequent sensitivity to parasitic lateral forces. To maximize the benefits from this sensor, particularly overload capability and long-term stability, in the high accuracy torque measurement application area, there is a need to develop significantly smaller devices. The aim of this thesis is to research through FEA modelling and experimental characterisation the key performance parameters required to produce a miniaturised metallic TBTF resonant sensor that provides better performance when applied in a torque measurement system. For high accuracy any torque transducer using these sensors ought to have low sensitivity to parasitic influences such as bending moments and lateral forces, which can only be achieved with reduced size. The problems with the existing design, key design issues, possible configuration and packaging solutions of the metallic TBTF resonant sensor that could be used for achieving a higher accuracy torque transfer standard are considered. Two designs of miniaturised metallic TBTF resonant sensors, SL20 and SL12, are considered and experimentally investigated. The lateral forces are reduced by 52% for SL20 design and by 80% for SL12 design when compared to the original SL40 design. A torque transducer using the SL20 design was calibrated falling into the Torque Transfer Standard class of accuracy 1 category, uncertainty 0.8%. A torque transducer using the SL12 design was made and calibration showed a class of accuracy 0.5 category, uncertainty 0.2%. The results from this research indicate that the SL12 design is suitable for use in a torque transfer standard. The SL12 design is optimal and the smallest size possible based on the overload capability design criteria requiring the tine cross sectional area to remain constant

Applied Measurement Systems

Measurement is a multidisciplinary experimental science. Measurement systems synergistically blend science, engineering and statistical methods to provide fundamental data for research, design and development, control of processes and operations, and facilitate safe and economic performance of systems. In recent years, measuring techniques have expanded rapidly and gained maturity, through extensive research activities and hardware advancements. With individual chapters authored by eminent professionals in their respective topics, Applied Measurement Systems attempts to provide a comprehensive presentation and in-depth guidance on some of the key applied and advanced topics in measurements for scientists, engineers and educators

Validação e instrumentação de sensores SAW para medição de binário e temperatura

Mestrado em Engenharia Eletrónica e TelecomunicaçõesThe work here presented is inserted in the framework of the RTMGear Project, that has the objective of measuring several physical parameters, such as torque and temperature, directly within the rotating parts present in a power reduction gearbox. The urge of this study comes from the aircraft industry demand for systems able to perform real-time monitoring of torque in the most critical components operating inside a gearbox. However, the existing sensing technologies have limitations in terms of accuracy. There are also considerable di culties to its implementation such as space constraints and very harsh conditions which make inappropriate the use of cables and electronic devices inside the gearbox. For this e ect, sensing devices based in SAW(Surface Acoustic Waves) technology were used. This devices are microelectromechanic (MEMS) systems whose characteristics are appropriate to the harsh conditions at hand. In order to proceed with the study two mechanical set- ups have been fabricated, to support the sensors evaluation tests. The rst consisted in a static set- up designed to proceed to the calibration of the strain sensors for torque measurement. The second was a dynamic set- up designed to reach rotation speed as high as 2500 rpm and with the capability of heating the sensors application area above its operating range. This set- up accommodated tests to evaluate the e ect of speed and temperature in the uncertainty of the measurements and nally, an experiment to perform torque measurement with temperature compensation was made. Tests to evaluate the curve dependence of the SAW sensors wrt temperature and the communication link established by two special antennas designated as RF rotary Couplers, used to establish wireless connection in rotative setups were also realized. The results obtained allowed the achievement of several conclusion regarding the work done and future improvements, given that a complete study on the sensors behaviour with respect to the physical quantities being analysed was made and conclusions about the e ect of speed and temperature in the measurements are obtained. However, in order to obtain validation of the technology for gearbox instrumentation, actual torque measurements in a broader range (0 to 250 Nm) with compensation of temperature and vibration, under broader ranges of speed (up to 3000 rpm) and temperature (between -25 oC up to 85o C or more) would have to be accomplished.O trabalho aqui apresentado está inserido no âmbito do projeto RTMGear, que visa a instrumentação e medição de grandezas físicas tais como binário e temperatura, diretamente a partir dos componentes rotativos da caixa de transmissão de testes, com a nalidade de validar a tecnologia usada para aplicação na indústria aeroespacial. A tecnologia estudada para realizar a monitorização em tempo real de tais grandezas são sensores SAW (sensores de onda acústica super cial) que se tratam de componentes microeletromecânicos (MEMS), com capacidade de medição em ambientes com condições difíceis como o que está a ser estudado. Com o objetivo de proceder ao estudo referido, dois set- ups mecânicos foram construídos e um conjunto de testes para estudar o comportamento dos sensores em tais condições foi efetuado: O primeiro, um set- up estático foi concebido para proceder à calibração dos sensores de binário para medição desta mesma grandeza, obtendo a curva de variação da sua resposta em função da gama de binário aplicada com recurso a uma máquina de testes universal. Foram ainda efetuados dois testes (um por tipo de sensor) com o intuito de obter as curvas de dependência dos sensores relativamente à temperatura. O segundo, um set- up dinâmico com capacidade de atingir rotação até próximo das 2500 rpm e com capacidade de proceder ao aquecimento da área de aplicação dos sensores até temperaturas superiores às compreendidas na sua gama de funcionamento. Neste Set- up testes para avaliar o efeito da aplicação de velocidade de rotação e temperatura no erro de medição e testes nais para apurar o binário medido com compensação do efeito da temperatura, após calibração prévia, foram efetuados. Os resultados obtidos com os procedimentos experimentais descritos permitiram retirar numerosas conclusões sobre o trabalho realizado mas são insu- cientes para validar a aplicação da tecnologia. Para tal, seriam necessários testes de medição de binário numa gama superior, com compensação de temperatura fossem realizados para valores de velocidade de rotação e temperatura signi cativamente superiores ao caso apresentado em que valores de binário foram efetivamente extraídos da realização experiemta

Development of a space qualified high reliability rotary actuator. Volume 1: Technical report

A space-qualified, high reliability, 150 ft-lb rated torque rotary acutator based on the Bendix Dynavector drive concept was developed. This drive is an integrated variable reluctance orbit motor-epicyclic transmission actuator. The performance goals were based on future control moment gyro torquer applications and represent a significant advancement in the torque-to-weight ratio, backlash, inertia and response characteristics of electric rotary drives. The program accomplishments have been in two areas: (1) the development of two high ratio (818:1) actuator configurations (breadboard and flightweight), and (2) the invention of a reliable proximity switch sensor system for self-commutation without use of optical or electrical brush techniques

Design and implementation of UAV performance validation system

Abstract. This thesis aims for design and implementation of a system for drone performance measurements, which can be used for validation of different drones for research projects accordingly. Additionally, the device should be able to be used as a part of a hardware-in-loop -system with simulators in drone research. The primary goal for this thesis is to build a system which helps to document different drone properties efficiently and safely. This is done with a system that consists of a robust frame, a force and torque measuring transducer, a drone stabilizing unit, a data logging system, and a remote-control power supply. For controlling the system, user interface was created to control the data stream, the drone stabilizing unit, and the power supply. This thesis includes a literature review of drone general classification properties and legal regulations. Short review of drone usage and selection criteria in industry and research is conducted, as well as in-depth review of the drone components and their relation to overall performance of the drone. The thesis also contains literature review of force and torque measuring theory, and other drone performance measuring units. The functionality of the designed unit is tested by building a drone from spare components, and valuating its performance based on e.g., lift generation, power consumption and visual behavior of the drone. Measured data is documented, and with the documents, drone’s suitability for future research projects can be assessed. According to the results, the unit can be used to evaluate drone’s performance, and groundwork for Hardware-in-loop simulator connection for drone research. The testing unit and the data recordings as well as the built testing drone stays within the research facility for further development.UAV testausjärjestelmän suunnittelu ja toteutus. Tiivistelmä. Tässä diplomityössä suunnitellaan ja valmistetaan droonien suorituskykyä mittaava tutkimuslaitteisto, jonka avulla voidaan arvioida erilaisten droonien soveltuvuutta tutkimusprojekteihin tapauskohtaisesti. Työssä tavoitellaan helppokäyttöistä järjestelmää, jonka avulla itse tehtyjen droonien ominaisuuksia voidaan dokumentoida turvallisesti ja tehokkaasti. Työssä perehdytään droonien luokitteluun tutustumalla voimassa oleviin säädöksiin, sekä droonin suorituskykyä kuvaaviin ominaisuuksiin. Työssä tarkastellaan droonien käyttöä eri aloilla arvioiden esiin nousseita droonin valintaperusteita ja ominaisuuksia. Tämän jälkeen tutustutaan droonien rakenteeseen ja ominaisuuksiin. Voiman mittauksen teoriaan sekä kehitettyihin mittausmenetelmiin tutustutaan tukemaan anturivalintaa. Suunniteltu järjestelmä koostuu tukevasta rungosta, voiman mittaukseen soveltuvasta anturista, droonin vakauttamisen kokonaisuudesta, datan keräysjärjestelmästä sekä etäohjattavasta virtalähteestä. Laitteiston ohjaukseen luotiin rajapinta, jonka kautta järjestelmää voidaan hallita. Järjestelmän toimivuus todettiin kahdella mittauskäyttöön soveltuvalla droonilla, joiden suorituskykyä arvioitiin droonien ominaisuuksien, sekä visuaalisen käyttäytymisen avulla. Mittauksien tulokset dokumentoitiin, ja dokumentaation perusteella voidaan arvioida sekä tutkimuslaitteiston toimivuutta, että mitattujen droonien soveltuvuutta tulevissa tutkimusprojekteissa. Mittausten perusteella voidaan todeta laitteen soveltuvan droonien suorituskyvyn mittaamiseen, sekä pohjatyöksi simulaattorikytkentään. Mittalaitteisto sekä mittaustulokset jäävät Biomimetiikka ja älykkäät järjestelmät -tutkimusyksikön käyttöön droonitutkimuksen tueksi