{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,1,13]],"date-time":"2026-01-13T09:44:49Z","timestamp":1768297489067,"version":"3.49.0"},"reference-count":13,"publisher":"MDPI AG","issue":"4","license":[{"start":{"date-parts":[[2015,3,27]],"date-time":"2015-03-27T00:00:00Z","timestamp":1427414400000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Sensors"],"abstract":"<jats:p>The production of large and complex parts using fiber composite materials is costly due to the frequent formation of voids, porosity and waste products. By embedding different types of sensors and monitoring the process in real time, the amount of wastage can be significantly reduced. This work focuses on developing a knowledge-based method to improve and ensure complete impregnation of the fibers before initiation of the resin cure. Piezoresistive and capacitive pressure sensors were embedded in fiber composite laminates to measure the real-time the pressure values inside the laminate. A change of pressure indicates resin infusion. The sensors were placed in the laminate and the resin was infused by vacuum. The embedded piezoresistive pressure sensors were able to track the vacuum pressure in the fiber composite laminate setup, as well as the arrival of the resin at the sensor. The pressure increase due to closing the resin inlet was also measured. In contrast, the capacitive type of sensor was found to be inappropriate for measuring these quantities. The following study demonstrates real-time monitoring of pressure changes inside the fiber composite laminate, which validate the use of Darcy\u2019s law in porous media to control the resin flow during infusion.<\/jats:p>","DOI":"10.3390\/s150407499","type":"journal-article","created":{"date-parts":[[2015,3,27]],"date-time":"2015-03-27T17:12:08Z","timestamp":1427476328000},"page":"7499-7511","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":30,"title":["Embedding Piezoresistive Pressure Sensors to Obtain Online Pressure Profiles Inside Fiber Composite Laminates"],"prefix":"10.3390","volume":"15","author":[{"given":"Maryam","family":"Moghaddam","sequence":"first","affiliation":[{"name":"Institute for Microsensors, Actuators and Systems (IMSAS), University of Bremen,  Otto-Hahn-Allee, NW1, 28359 Bremen, Germany"}]},{"given":"Arne","family":"Breede","sequence":"additional","affiliation":[{"name":"Faserinstitut Bremen e.V. (FIBRE), Geb\u00e4ude IW3, Am Biologischen Garten 2, 28359 Bremen, Germany"}]},{"given":"Christian","family":"Brauner","sequence":"additional","affiliation":[{"name":"Faserinstitut Bremen e.V. (FIBRE), Geb\u00e4ude IW3, Am Biologischen Garten 2, 28359 Bremen, Germany"}]},{"given":"Walter","family":"Lang","sequence":"additional","affiliation":[{"name":"Institute for Microsensors, Actuators and Systems (IMSAS), University of Bremen,  Otto-Hahn-Allee, NW1, 28359 Bremen, Germany"}]}],"member":"1968","published-online":{"date-parts":[[2015,3,27]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"935","DOI":"10.1016\/j.compositesa.2012.01.003","article-title":"Out-of-autoclave cure cycle study of a resin film infusion process using in situ process monitoring","volume":"43","author":"Garschke","year":"2012","journal-title":"Compos. Part A Appl. Sci. Manuf."},{"key":"ref_2","doi-asserted-by":"crossref","first-page":"1433","DOI":"10.1016\/S1359-835X(00)00140-8","article-title":"Improving the resin transfer moulding process for fabric-reinforced composites by modification of the fabric architecture","volume":"31","author":"Pearce","year":"2000","journal-title":"Compos. Part A Appl. Sci. Manuf."},{"key":"ref_3","doi-asserted-by":"crossref","first-page":"3281","DOI":"10.1016\/j.compscitech.2005.07.008","article-title":"Analysis and minimization of void formation during resin transfer molding process","volume":"66","author":"Lee","year":"2006","journal-title":"Compos. Sci. Technol."},{"key":"ref_4","doi-asserted-by":"crossref","first-page":"2427","DOI":"10.1016\/S0266-3538(00)00036-1","article-title":"Formation of microvoids during resin-transfer molding process","volume":"60","author":"Kang","year":"2000","journal-title":"Compos. Sci. Technol."},{"key":"ref_5","doi-asserted-by":"crossref","first-page":"2156","DOI":"10.1063\/1.1148065","article-title":"Fiber optic sensors for use in monitoring flow front in vacuum resin transfer molding processes","volume":"68","author":"Bernstein","year":"1997","journal-title":"Rev. Sci. Instrum."},{"key":"ref_6","doi-asserted-by":"crossref","unstructured":"Mrad, N., Sidharan, A., and Kazemi, A. (2014, January 17). Pressure sensitivity of fiber bragg grating sensors. Proceedings of the Conference on Photonics Applications for Aviation, Aerospace, Commercial, and Harsh Environments V, San Diego, CA, USA.","DOI":"10.1117\/12.2063103"},{"key":"ref_7","doi-asserted-by":"crossref","first-page":"1","DOI":"10.1063\/1.2432258","article-title":"Ultrasonic torsional guided wave sensor for flow front monitoring inside molds","volume":"78","author":"Visvanathan","year":"2007","journal-title":"Rev. Sci. Instrum."},{"key":"ref_8","first-page":"25","article-title":"1D-permeability measurements based on ultrasound and linear direct current resistance monitoring techniques","volume":"10","author":"Luthy","year":"2001","journal-title":"J. Mater. Process. Manuf. Sci."},{"key":"ref_9","first-page":"691","article-title":"A Prediction Method for in-Plane Permeability and Manufacturing Applications in the VARTM Process","volume":"3","author":"Lee","year":"2011","journal-title":"Sci. Res."},{"key":"ref_10","doi-asserted-by":"crossref","first-page":"476","DOI":"10.1016\/j.compositesa.2009.01.014","article-title":"A Grid of Dielectric Sensors to Monitor Mold Filling and Resin Cure in Resin Transfer molding","volume":"40","author":"Yenilmez","year":"2009","journal-title":"Compos. Part A Appl. Sci. Manuf."},{"key":"ref_11","doi-asserted-by":"crossref","first-page":"1363","DOI":"10.1016\/j.compositesa.2006.10.009","article-title":"Constraints on monitoring resin flow in the resin transfer molding (RTM) process by using thermocouple sensors","volume":"38","author":"Tuncol","year":"2007","journal-title":"Compos. Part A Appl. Sci. Manuf."},{"key":"ref_12","doi-asserted-by":"crossref","unstructured":"Dave, R.S., and Loos, A.C. (2000). Processing of Composites, Hanser\/Gardner Publications.","DOI":"10.3139\/9783446401778.fm"},{"key":"ref_13","doi-asserted-by":"crossref","first-page":"1","DOI":"10.1016\/j.compositesa.2012.11.008","article-title":"A methodology for flow-front estimation in LCM processes based on pressure sensors","volume":"47","author":"Klunker","year":"2013","journal-title":"Compos. Part A Appl. Sci. Manuf."}],"container-title":["Sensors"],"original-title":[],"language":"en","link":[{"URL":"https:\/\/www.mdpi.com\/1424-8220\/15\/4\/7499\/pdf","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2025,10,11]],"date-time":"2025-10-11T20:44:03Z","timestamp":1760215443000},"score":1,"resource":{"primary":{"URL":"https:\/\/www.mdpi.com\/1424-8220\/15\/4\/7499"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2015,3,27]]},"references-count":13,"journal-issue":{"issue":"4","published-online":{"date-parts":[[2015,4]]}},"alternative-id":["s150407499"],"URL":"https:\/\/doi.org\/10.3390\/s150407499","relation":{},"ISSN":["1424-8220"],"issn-type":[{"value":"1424-8220","type":"electronic"}],"subject":[],"published":{"date-parts":[[2015,3,27]]}}}