Characterization of Interdigital Capacitive Strain Gauges by Direct Write Technology

2005 ◽  
Author(s):  
Jinggao Li ◽  
Jon P. Longtin ◽  
Szymon Tankiewicz ◽  
Andrew Gouldstone ◽  
Sanjay Sampath
Keyword(s):  
Printed Circuit Boards ◽  
Thermal Spray Technology ◽  
Mechanical Tests ◽  
Ultrafast Laser ◽  
Strain Gauges ◽  
Gauge Factor ◽  
Direct Write ◽  
Circuit Boards ◽  
Capacitive Strain ◽  
Controlled Deposition

Interdigitated capacitive strain gauges have several distinct advantages over resistive-based strain gauges, particularly for applications in harsh environments, such as high-temperature environments. In this work capacitive strain gauges have been fabricated using thermal spray technology. Gauges are fabricated using both a direct-write approach where the gauge is fabricated using a computer-controlled deposition system and by ultrafast laser micromachining in which blanket coatings sprayed onto a substrate are subsequently laser micrornachined. Silver coatings were sprayed onto plastic, polymer, composites, fiberglass and alumina to form the strain gauges. An ultrafast laser machining technique was used to fabricate capacitive strain gauges on copper coated printed circuit boards as well as NiCr coatings on alumina substrate. The typical capacitance of strain gauge was in the range of 5∼25 pF. Mechanical tests included gauge factor, linearity and zero shift. Temperature-based measurements include the temperature coefficient of capacitance (TCC) measurements and thermal cycling tests. The devices show promise for use in wireless strain monitoring applications.

Interdigital capacitive strain gauges fabricated by direct-write thermal spray and ultrafast laser micromachining

2007 ◽  
Vol 133 (1) ◽  
pp. 1-8 ◽  
Author(s):  
Jinggao Li ◽  
Jon P. Longtin ◽  
Szymon Tankiewicz ◽  
Andrew Gouldstone ◽  
Sanjay Sampath
Keyword(s):  
Thermal Spray ◽  
Laser Micromachining ◽  
Ultrafast Laser ◽  
Strain Gauges ◽  
Direct Write ◽  
Capacitive Strain

Mechanical Test of FPCB and Failure Analysis by Simulation

2009 ◽  
Author(s):  
Jian Zhong ◽  
Ping Yang ◽  
Jian-ping Li ◽  
Hai-bo Sun ◽  
Quayle Chen ◽  
...  
Keyword(s):  
Failure Analysis ◽  
Printed Circuit Boards ◽  
Simulation Analysis ◽  
Mechanical Test ◽  
Mechanical Tests ◽  
Stress Distributions ◽  
Circuit Boards ◽  
Printed Circuit ◽  
Depth Analysis ◽  
Flexible Printed Circuit

The paper mainly presented mechanical test and failure analysis methods to reliability study of a new FPCB (Flexible Printed Circuit Boards). Mechanical tests include flexural test, tensile test and flexural fatigue and ductility test. As to simulation analysis, the stress distributions of FPCB under bending and tensile conditions were gained by simulations. Through in-depth analysis of the testing results, the mechanical reliability of FPCB was known detailed. The research provides an approach to improve FPCB performance.

Ultrafast Laser Micromachining and Patterning of Thermal Spray Multilayers for Novel Sensor Fabrication

2003 ◽  
Author(s):  
Q. Chen ◽  
J. P. Longtin ◽  
S. Sampath ◽  
R. J. Gambino
Keyword(s):  
Thermal Spray ◽  
Thermal Spray Technology ◽  
Laser Micromachining ◽  
Ultrafast Laser ◽  
Direct Write ◽  
Additive Process ◽  
Pattern Design ◽  
Wide Range ◽  
Functional Patterns ◽  
Rapid Prototyping And Manufacturing

Fabrication of structural and functional parts and components, especially at the micro and nano scales, is crucial to a wide range of applications in the electronics, communications, medical, aerospace, and military industries. This work presents an innovative conformal direct-write technique for rapid prototyping and manufacturing novel sensors. The technique combines thermal spray, which, as an additive process, produces blanket depositions of films and coatings, with ultrafast laser micromachining, a subtractive process to produce functional patterns. Several kinds of sensing components, such as microheaters and strain gauges, have been successfully fabricated in this work with thermal spray technology and a femtosecond laser, which demonstrates the feasibility and advantages of the proposed technique. The electrical and thermal property characterization of the sensors was also performed, and shows promise for sensors in micro-sensing systems. With minor modification to pattern design and processing procedures, various sensing structures and electronic components, for example, precision resistors and interdigitated capacitors, can be readily fabricated using the presented technique.

Performance Characteristics of Additively Printed Strain Gauges Under Different Conditions of Temperature and High Stress Loads

2021 ◽  
Author(s):  
Pradeep Lall ◽  
Tony Thomas ◽  
Jinesh Narangaparambil
Keyword(s):  
Strain Gauge ◽  
High Stress ◽  
Consumer Electronics ◽  
Performance Characteristics ◽  
Curing Temperature ◽  
Strain Gauges ◽  
Gauge Factor ◽  
Direct Write ◽  
Commercial Strain ◽  
Silver Ink

Abstract Applications of printed sensors have increased to industrial, consumer electronics, and medical fields with the advancements in the technology of printing and the adaptability of ink. These sensors are used to monitor a variety of measurements, including temperature, humidity, strain, and sweat, with different systems. This paper studies the performance characteristics of additively printed strain sensors using a nScrypt machine with a direct-write printing technique. The ink used in this study is silver ink which is thermally cured and also has a solderable property. The thermal curing temperature and trace width of the printed silver trace is optimized for better performance in the strain measurements, shear load to failure, and resistivity. Once the printing characteristics of the trace are defined, strain gauges are printed on printed wiring boards (PWB) and are tested at different loading and temperature environments. The sustainability and repeatability of the sensor measurements at high-stress conditions are studied using combined temperature and vibration loads of up to 50 degrees Celsius and 10g acceleration levels. The strain characteristics of the printed strain gauges are studied by comparing them to a commercial strain gauge at a similar position on the test substrate. The repeatability and variation of the strain profile are studied with different conditions of temperature and acceleration conditions at different time instants during vibration. The gauge factor of the printed strain gauge is quantified using a 3-point bending experiment with printed and commercial strain gauges at symmetrical locations of the substrate.

Sign in / Sign up

Export Citation Format

Share Document