Related Experiment Video
Updated: Feb 6, 2026

Hybrid Printing for the Fabrication of Smart Sensors
Published on: January 31, 2019
Design, Fabrication and Testing of a High-Sensitive Fibre Sensor for Tip Clearance Measurements
Gaizka Durana1, Josu Amorebieta2, Ruben Fernandez3
1Communications Engineering Department, University of the Basque Country (UPV/EHU), Ingeniero Torres Quevedo Plaza 1, E-48013 Bilbao, Spain. gaizka.durana@ehu.eus.
Abstract:
A highly sensitive fibre bundle-based reflective optical sensor has been designed and fabricated for Tip Clearance measurements in a turbine rig. The sensor offers high spatial and temporal resolution. The sensor probe consists of a single-mode transmitting fibre and two concentric rings of receiving multimode fibres that collect reflected light in a differential detection gain configuration, yielding a highly linear calibration curve for distance measurements. The clearance measurement range is approximately 2 mm around the central point fixed at 3.2 mm from the probe tip, and the sensitivity of the probe is 61.73 mm-1. The fibre bundle has been designed to ensure that the distance security specifications required for the experimental program of the turbine are met. The optical sensor has operated under demanding conditions set by the blade and casing design. The experimental results obtained so far are promising and lead us to think that the optical sensor has great potential for online clearance measurements with high precision.
Related Concept Videos
Design Example: Measuring Distance Between Two Points with Obstructions
Group Design
Hepatic Drug Clearance: Restrictive and Nonrestrictive Clearance
Most drugs undergo restrictive clearance, which is proportional to the...
Renal Clearance
Renal clearance refers to the volume of plasma cleared of a specific substance, such as creatinine, per unit of time. To measure clearance, urine samples are collected over a 24-hour period during each bladder voiding, followed by a single blood sample at the...
Drug Dosing in Renal Diseases: Measurement of Serum Creatinine Concentration and Clearance
Bioequivalence Experimental Study Designs: Repeated Measures, Cross-Over, Carry-Over, and Latin Square Designs

