Prognostication and health monitoring of leaded and lead free electronic and MEMS packages in harsh environments

2005 ◽  
Author(s):  
P. Lall ◽  
N. Islam ◽  
J. Suhling
Keyword(s):  
Health Monitoring ◽  
Lead Free ◽  
Harsh Environments

scholarly journals Infrared Thermography Measurement for Vibration-Based Structural Health Monitoring in Low-Visibility Harsh Environments

Sensors ◽  
2020 ◽  
Vol 20 (24) ◽  
pp. 7067
Author(s):  
Jia-Hao He ◽  
Ding-Peng Liu ◽  
Cheng-Hsien Chung ◽  
Hsin-Haou Huang
Keyword(s):  
Structural Health Monitoring ◽  
Infrared Thermography ◽  
Mode Shape ◽  
Health Monitoring ◽  
Large Scale ◽  
Frame Structure ◽  
Harsh Environments ◽  
Thermal Imager ◽  
Heat Sources ◽  
Structural Health

In this study, infrared thermography is used for vibration-based structural health monitoring (SHM). Heat sources are employed as sensors. An acrylic frame structure was experimentally investigated using the heat sources as structural marker points to record the vibration response. The effectiveness of the infrared thermography measurement system was verified by comparing the results obtained using an infrared thermal imager with those obtained using accelerometers. The average error in natural frequency was between only 0.64% and 3.84%. To guarantee the applicability of the system, this study employed the mode shape curvature method to locate damage on a structure under harsh environments, for instance, in dark, hindered, and hazy conditions. Moreover, we propose the mode shape recombination method (MSRM) to realize large-scale structural measurement. The partial mode shapes of the 3D frame structure are combined using the MSRM to obtain the entire mode shape with a satisfactory model assurance criterion. Experimental results confirmed the feasibility of using heat sources as sensors and indicated that the proposed methods are suitable for overcoming the numerous inherent limitations associated with SHM in harsh or remote environments as well as the limitations associated with the SHM of large-scale structures.

scholarly journals Development of a Novel Sensor for Gear Teeth Wear and Damage Detection

2021 ◽  
Vol 12 (3) ◽  
Author(s):  
Vikram Sridhar ◽  
Kam Chana
Keyword(s):  
Damage Detection ◽  
Eddy Current ◽  
Health Monitoring ◽  
Harsh Environments ◽  
Tooth Surface ◽  
Mechanical Transmission ◽  
Transmission Systems ◽  
Gear Teeth ◽  
Gear Box ◽  
Current Sensors

Health monitoring of mechanical transmission systems is an important area of research. Mechanical transmission systems, especially gear boxes in aircraft, automobiles, and wind turbines etc. account for many of the maintenance costs due to repairs, replacements and downtime. Gear boxes can experience high level of failure due to varied load conditions and harsh environments. Replacing the gear box is quite an expensive process and has significant downtime. Current gear box monitoring involves mainly measuring vibrations, however vibrations occur when the fault in the gear has already progressed significantly. Gear teeth monitoring lacks sensor technology to successfully detect tooth damage and misalignment. This paper presents a new concept gear teeth damage detection using eddy current sensors fitted on to the teeth of an idler gear at various locations. These sensors detect various faults encountered in a gear such as micro and macro pitting of the tooth surface, contact wear etc. Eddy current sensors are already being used to detect turbomachinery blade vibrations and tip clearance as they are robust and immune to contamination. In the present case, we use an idler gear that incorporates miniature eddy current sensors and state of the art electronics with wireless data transmission to enable the device to operate remotely and in harsh environments. A rotating rig with gears (spur and helical) and oil supply was built to test and validate the sensor by seeding various faults on the tooth surface. The results show that the idler sensor gear was able to detect various faults. The new eddy current sensor idler gear concept will enable health monitoring of the gearbox and ensure timely maintenance and reduction in operation costs.

Structural Health Monitoring Using Iot

2019 ◽  
pp. 144-147
Author(s):  
Sureshkumar M.P ◽  
Vennila G.
Keyword(s):  
Structural Health Monitoring ◽  
Construction Industry ◽  
Health Monitoring ◽  
Continuous Monitoring ◽  
Processing Technique ◽  
Harsh Environments ◽  
Signal Processing Technique ◽  
Computing Technique ◽  
Structural Health ◽  
The World

In construction industry maintenance should be given utmost importance and focus. For continuous monitoring of maintenance Internet of Things (IoT) can be used. IoT can be used to monitor the structure from anywhere. Structural health monitoring using IoT is the latest technique employed all over the world, especially the buildings exposed to harsh environments. Sensors were used to collect the data from the structure from which we can identify the deterioration and the method to rectify. Cloud computing technique was also employed. A simple signal processing technique helps us to interact with buildings, which was the blessing of IoT.  This paper presents the state of art survey about current research and implementations put into practice.

scholarly journals State-of-the-Art and Practical Guide to Ultrasonic Transducers for Harsh Environments Including Temperatures above 2120 °F (1000 °C) and Neutron Flux above 1013 n/cm2

Sensors ◽  
2019 ◽  
Vol 19 (21) ◽  
pp. 4755 ◽  
Author(s):  
Tittmann ◽  
Batista ◽  
Trivedi ◽  
Lissenden III ◽  
Reinhardt
Keyword(s):  
High Temperature ◽  
Lithium Niobate ◽  
Thick Film ◽  
Health Monitoring ◽  
Thermal Flux ◽  
Ultrasonic Transducers ◽  
Nuclear Radiation ◽  
Harsh Environments ◽  
Harsh Environment ◽  
Weiss Temperature

In field applications currently used for health monitoring and nondestructive testing, ultrasonic transducers primarily employ PZT5-H as the piezoelectric element for ultrasound transmission and detection. This material has a Curie–Weiss temperature that limits its use to about 210 °C. Some industrial applications require much higher temperatures, i.e., 1000–1200 °C and possible nuclear radiation up to 1020 n/cm2 when performance is required in a reactor environment. The goal of this paper is the survey and review of piezoelectric elements for use in harsh environments for the ultimate purpose for structural health monitoring (SHM), non-destructive evaluation (NDE) and material characterization (NDMC). The survey comprises the following categories: 1. High-temperature applications with single crystals, thick-film ceramics, and composite ceramics, 2. Radiation-tolerant materials, and 3. Spray-on transducers for harsh-environment applications. In each category the known characteristics are listed, and examples are given of performance in harsh environments. Highlighting some examples, the performance of single-crystal lithium niobate wafers is demonstrated up to 1100 °C. The wafers with the C-direction normal to the wafer plane were mounted on steel cylinders with high-temperature Sauereisen and silver paste wire mountings and tested in air. In another example, the practical use in harsh radiation environments aluminum nitride (AlN) was found to be a good candidate operating well in two different nuclear reactors. The radiation hardness of AlN was evident from the unaltered piezoelectric coefficient after a fast and thermal neutron exposure in a nuclear reactor core (thermal flux = 2.12 × 1013 ncm−2; fast flux 2 (>1.0 MeV) = 4.05 × 1013 ncm−2; gamma dose rate: 1 × 109 r/h; temperature: 400–500 °C). Additionally, some of the high-temperature transducers are shown to be capable of mounting without requiring coupling material. Pulse-echo signal amplitudes (peak-to-peak) for the first two reflections as a function of the temperature for lithium niobate thick-film, spray-on transducers were observed to temperatures of about 900 °C. Guided-wave send-and-receive operation in the 2–4 MHz range was demonstrated on 2–3 mm thick Aluminum (6061) structures for possible field deployable applications where standard ultrasonic coupling media do not survive because of the harsh environment. This approach would benefit steam generators and steam pipes where temperatures are above 210 °C. In summary, there are several promising approaches to ultrasonic transducers for harsh environments and this paper presents a survey based on literature searches and in-house laboratory observations.

Poling effects on the performance of a lead-free piezoelectric nanofiber in a structural health monitoring sensor

2017 ◽  
Vol 263 ◽  
pp. 633-638 ◽  
Author(s):  
Sang Hyun Ji ◽  
Jeong Ho Cho ◽  
Jong-Hoo Paik ◽  
Jondo Yun ◽  
Ji Sun Yun
Keyword(s):  
Structural Health Monitoring ◽  
Health Monitoring ◽  
Lead Free ◽  
Structural Health
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