Software Development for Automatic Processing of Standard Platinum Resistance Thermometer Verification Data

In situ temperature monitoring of curved high-temperature components in extreme environments is challenging for a variety of applications in fields such as aero engines and gas turbines. Recently, extrusion-based direct ink writing (DIW) has been utilized to fabricate platinum (Pt) resistance temperature detectors (RTDs). However, the current Pt RTD prepared by DIW technology suffers from a limited temperature range and poor high-temperature stability. Here, DIW technology and yttria-stabilized zirconia (YSZ)-modified precursor ceramic film packaging have been used to build a Pt RTD with high-temperature resistance, small disturbance, and high stability. The results indicate that the protective layer formed by the liquid phase anchors the Pt particles and reduces the agglomeration and volatilization of the Pt sensitive layer at high temperature. Attributed to the SiCN/YSZ protective layer, the temperature resistance curve of the Pt RTD in the range of 50-800 °C has little deviation from the fitting curve, and the fitting correlation coefficient is above 0.9999. Interestingly, the Pt RTD also has high repeatability and stability. The high temperature resistance drift rate is only 0.05%/h after 100 h of long-term testing at 800 °C and can withstand butane flame up to ∼1300 °C without damage. Moreover, the Pt RTD can be conformally deposited on the outer ring of aerospace bearings by DIW technology and then realize on-site, nondestructive, and real-time monitoring of bearing temperature. The fabricated Pt RTD shows great potential for high-temperature applications, and the novel technology proposed provides a feasible pathway for temperature monitoring of aeroengine internal curved hot-end components.

Platinum resistance thermometers (PRTs) provide accurate temperature measurements over a wide temperature range and are used extensively on space missions due to their simplicity and linearity. A standard on spacecraft, PRTs are used to provide precision temperature control and vehicle health assessment. This paper reviews the extensive reliability testing of platinum resistor thermometer sensors (PRTs) and bonding methods used on the Mars Science Laboratory (MSL) mission and for the upcoming Soil Moisture Active Passive (SMAP) mission. During the Mars Exploration Rover (MER) mission, several key, JPL-packaged PRTs failed on those rovers prior to and within 1-Sol of landing due to thermally induced stresses. Similar failures can be traced back to other JPL missions dating back thirty years. As a result, MSL sought out a PRT more forgiving to the packaging configurations used at JPL, and extensively tested the Honeywell HRTS-5760-B-U-0-12 sensor to successfully demonstrate suitable robustness to thermal cycling. Specifically, this PRT was cycled 2,000 times, simulating three Martian winters and summers. The PRTs were bonded to six substrate materials (Aluminum 7050, treated Magnesium AZ231-B, Stainless Steel 304, Albemet, Titanium 6AL4V, and G-10), using four different aerospace adhesives--two epoxies and two silicones--that conformed to MSL's low out-gassing requirements. An additional epoxy was tested in a shorter environmental cycling test, when the need for a different temperature range adhesive was necessary for mobility and actuator hardware late in the fabrication process. All of this testing, along with electrostatic discharge (ESD) and destructive part analyses, demonstrate that this PRT is highly robust, and not subject to the failure of PRTs on previous missions. While there were two PRTs that failed during fabrication, to date there have been no in-flight PRT failures on MSL, including those on the Curiosity rover. Since MSL, the sensor has gone through a change in construction such that the manufacturer significantly restricts the minimum temperature. However, significant subsequent testing was performed with this new version of the part to show that it indeed is still robust to at least Mars minimum temperatures of -135(sup o)C. The additional completed testing will be described. This work has resulted in a successful sensor package qualification and a reliable bonding method suitable for use over large temperature extremes.

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Resistance temperature detectors are commonly used measurement sensors in heat transfer studies. In many resistance temperature detectors, the platinum resistance thermometer (PRT) is chemically stable, has a wide temperature measurement range and possesses high measurement accuracy. In phase change studies of carbon nanotubes, bi-porous structures for microelectronic thermal management, 100 nm thick PRTs are developed on silicon substrates with 10 nm titanium adhesive to achieve precise and interface-free temperature measurements. After an annealing at 375 °C, the PRT samples are calibrated at a temperature range from 20 to 180 °C. Measurement hysteresis of temperature appears in thermal cycles. Electrical resistance tends to become low during all heating periods, which establishes the maximum measurement deviation of 10 °C. Experimental results from two different thin-film PRTs indicate that accurate and repeatable temperature measurements can be achieved by either reducing heating speed or using data in the cooling period.

A procedure for the precise determination and compensation of the lead-wire resistance of a resistance transducer is presented. The proposed technique is suitable for a two-wire resistance transducer, especially the resistance temperature detector (RTD). The proposed procedure provides a technique to compensate for the lead-wire resistance using a three-level pulse signal to excite the RTD via the long lead wire. In addition, the variation in the lead-wire resistance disturbed by the change in the ambient temperature can also be compensated by using the proposed technique. The determination of the lead-wire resistance from the proposed procedure requires a simple computation method performed by a digital signal processing unit. Therefore, the calculation of the RTD resistance and the lead-wire resistance can be achieved without the requirement of a high-speed digital signal processing unit. The proposed procedure is implemented on two platforms to confirm its effectiveness: the LabVIEW computer program and the microcontroller board. Experimental results show that the RTD resistance was accurately acquired, where the measured temperature varied from 0 °C to 300 °C and the lead-wire resistance varied from 0.2 Ω to 20 Ω, corresponding to the length of the 26 American wire gauge (AWG) lead wire from 1.5 m to 150 m. The average power dissipation to the RTD was very low and the self-heating of the RTD was minimized. The measurement error of the RTD resistance observed for pt100 was within ±0.98 Ω or ±0.27 °C when the lead wire of 30 m was placed in an environment with the ambient temperature varying from 30 °C to 70 °C. It is evident that the proposed procedure provided a performance that agreed with the theoretical expectation.

Metal-based sandwich type thick-film platinum resistance temperature detector for in-situ temperature monitoring of hot-end components

This experience report describes the successful application of statistical software testing to a large-scale realworld equipment replacement project. The Data Processing System at Dungeness B nuclear power station is obsolescent and needs to be replaced by a new system involving different technology. The new Data Processing and Control System (DPCS) involves a large amount of software code, with the potential for software failures, and therefore confidence needs to be established in the dependability of the new software-based system. Statistical software testing (ST) was used as one technique to do this. The aim was to support the claim that with high confidence the higher integrity parts of the replacement software have a failure probability of better than 10-2 failures per demand (fpd). This paper describes how this has been achieved by careful design of the statistical tests and by the development of a large number of supporting tools and procedures. A total of 395 statistical tests with no failure was achieved providing at least 98% confidence that the safety claim has been met.

Recent studies on dynamic temperature profiling and lithographic performance modeling of the post-exposure bake (PEB) process have demonstrated that the rate of heating and cooling may have an important influence on resist lithographic response. Measuring the transient surface temperature during the heating or cooling process with such accuracy can only be assured if the sensors embedded in or attached to the test wafer do not affect the temperature distribution in the bare wafer. In this paper we report on an experimental and analytical study to compare the transient response of embedded platinum resistance thermometer (PRT) sensors with surface-deposited, thin-film thermocouples (TFTC). The TFTCs on silicon wafers have been developed at NIST to measure wafer temperatures in other semiconductor thermal processes. Experiments are performed on a test bed built from a commercial, fab-qualified module with hot and chill plates using wafers that have been instrumented with calibrated type-E (NiCr/CuNi) TFTCs and commercial PRTs. Time constants were determined from an energy-balance analysis fitting the temperature-time derivative to the wafer temperature during the heating and cooling processes. The time constants for instrumented wafers ranged from 4.6 s to 5.1 s on heating for both the TFTC and PRT sensors, with an average difference less than 0.1 s between the TFTCs and PRTs and slightly greater differences on cooling.

Within the International Temperature Scale of 1990 (ITS-90) the platinum resistance thermometer (PRT) is used to realize the scale from approximately 13,8 K to 1 235 K. Such a temperature range is wider than the corresponding range in the International Practical Temperature Scale of 1968 (IPTS-68) because the PRT is used up to the freezing point of silver (1 234,93 K). In this way, the ITS-90 can be realized with much more precision than the IPTS-68, particularly between 901 K and 1 235 K where the standard Pt-10% Rh vs Pt thermocouple was previously used.This paper describes some important steps in the construction of the PRT reference function and the criteria for the selection of the PRT interpolating equations of the ITS-90. In contrast to previous international scales, the PRT range of the ITS-90 is based on two reference functions, one from 13,8 K to 273,16 K and the other from 273,15 K to 1 234,93 K. The two reference functions were obtained from two real PRTs.A set of interpolating equations is used to account for the differences of other real PRTs from those on which the reference functions are based. They provide flexibility of calibration and high precision as expressed, for instance, by non-uniqueness and sub-range inconsistency not exceeding 0,5 mK over the range from 13,8 K to 693 K. Such good properties are the consequence of the choice of suitable forms for the interpolating equations and of fine adjustments in the values assigned to some defining fixed points.

In a recent paper on deviations from Matthiessen's rule for platinum Klemens and Lowenthal (1961) classified the deviation patterns, calculated for a number of different platinum resistance thermometers, into three groups, and reported that only one of these groups followed the pattern predicted by Sondheimer and Wilson's (1947) two-band conduction theory. They suggested that if resistors belonging to one particular group (though no matter which group) were selected for use in low temperature platinum resistance thermometry then the resistance-temperature relationship could be expressed accurately by a relatively simple formula. We believe that Klemens and Lowenthal's method of classifying the resistors into groups is open to serious objection and that consequently some of their important conclusions are not necessarily valid.

This article indicates the status of platinum resistance thermometry in temperature definition and measurement and outlines some potential sources of error. Perhaps the most important factor requiring consideration is the influence of thermometer structural materials on conformity with the IPTS-68. An analysis of calibration measurements, including data reported in earlier work, strengthens the hypothesis that stem heat transmission can contribute discrepancies greater than those that would arise as a result of applying the IPTS-68 to thermometers having low temperature coefficients of resistance (e g, 3.850 x 10-3 per K). Indeed, with the available data it is impossible to discern any systematic effect of temperature coefficient on deviation from the IPTS-68. Quantitative illustration of the various features discussed is included where appropriate.

This paper presents a new experimental method and algorithm for the determination of self-heating of platinum resistance thermometer (PRT) when the temperature instability of medium of interest would prevent an accurate self-heating determination using standard methods. In temperature measurements performed by PRT, self-heating is one of the most common sources of error and arises from the increase in sensor temperature caused by the dissipation of electrical heat when measurement current is applied to the temperature sensing element. This increase depends mainly on the applied current and the thermal resistances between thermometer sensing element and the environment surrounding the thermometer. The method is used for determination of self-heating of a 100 $$\Omega $$ industrial PRT which is intended for measurement of air temperature inside the saturation chamber of the primary dew/frost point generator at the Laboratory for Process Measurement (HMI/FSB-LPM). Self-heating is first determined for conditions present during the comparison calibration of the thermometer, using the calibration bath. The measurements were then repeated with thermometer being placed in an air stream inside the saturation chamber. The experiment covers the temperature range between $$-65{\,}^{{\circ }}\hbox {C}$$ and $$10{\,}^{{\circ }}\hbox {C}$$ . Self-heating is determined for two different air velocities and two different vertical positions of PRT in relation to the chamber bottom.

A novel temperature difference-to-frequency (TD/F) converter using two platinum resistance temperature detectors (RTDs) has been developed. The resistance difference of two RTDs is converted into a DC current to control the simulated inductor, which is designed so that its inductance is inversely proportional to the square of the current. The simulated inductor forms the resonant circuit of a Colpitts oscillator and hence the oscillation frequency becomes directly proportional to the resistance difference. A conversion sensitivity of 16 Hz/ degrees C and a residual nonlinearity of less than 2% over the temperature difference range of 35 degrees C to 155 degrees C are obtained by the prototype converter which oscillates at 667 Hz at a 51 degrees C temperature difference. The minimum detectable temperature difference is estimated to be +or-0.013 degrees C. The power dissipations in the RTDs are about 2 mu W. The proposed converter, except for the RTDs, can be fabricated in a monolithic IC form by scaling the component values. >

Thin-film platinum resistance thermometer for use at low temperatures and in high magnetic fields

In this paper, we propose a novel automatic approach for personalized music sports video generation. Two research challenges, semantic sports video content selection and automatic video composition, are addressed. For the first challenge, we propose to use multi-modal (audio, video and text) feature analysis and alignment to detect the semantic of events in sports video. For the second challenge, we propose video-centric and music-centric music video composition schemes to automatically generate personalized music sports video based on user's preference. The experimental results and user evaluations are promising and show that our system's generated music sports video is comparable to manually generated ones. The proposed approach greatly facilitates the automatic music sports video generation for both professionals and amateurs.