A laser triangulation sensor for vibrational structural analysis and diagnostics

Abstract

The industrial progress has reached a level in which it is necessary to understand the behavior of mechanical components and to monitor their conditions without disassembling them. Nowadays, a suitable methodology is based on vibrational analysis usually performed through acceleration signals measured directly on the system to be tested. However, in the last years, the industrial scenario has deeply changed due to the need for time reduction, in particular, for the control operations at the end of the productive line. The genuine methods based on acceleration measurements, for example, through piezoelectric accelerometers, came into conflict with the industrial need as the sensors used for the quality control have to be easily and fastly mounted and unmounted. A valid alternative is represented by the exploitation of laser triangulation sensors that are able to measure the dynamic displacement in a contactless way, strongly reducing the (un)mounting time. The target of this paper is to highlight pros and cons of the contactless displacement analysis through laser triangulation sensors with respect to the contact one through genuine accelerometers by means of a comparison between the results obtained both for experimental modal analysis and vibrational diagnostics of rotating machines.

Using a Gauge Block for Derivation of Parameters of Four Laser Triangulation Sensors in a Local Coordinate System

“…However, the need of higher resolution comes into conflict with the measuring range of the transducer." -state the authors of [7].…”

“…1) using the laser triangulation principle described in [4,5]. Measurement setups using one LTS were already presented, e.g., a system for the real-time gauge measurement in a train [6] or a system for the contactless dynamic displacement measurement [7]. A measuring system for online quality control of car engine block has been presented in [8].…”

Automate Quality Prediction in an End-of-Line Test of a Highly Variant Production of Geared Motors – Discussion of a Full Concept

“…Some contact-free, laser-based measuring techniques exist. But position-based techniques, such as triangulation have resolution problems in the higher frequency range (Soave, D'Elia, & Mucchi, 2020). Acoustic measurements are an obvious choice, since quality issues reported by a customer are often associated to sound quality.…”

System parameter optimization with improved genetic algorithm for laser triangulation sensors

“…Laser triangulation systems, as non-contact measurement instruments with high accuracy, strong stability, and fast response, have been widely applied in various fields such as contour measurement reconstruction, 1 surface defect detection, 2 vibration structure analysis, 3 and diagnostics. In different measurement scenarios, users have varying demands for resolution and range in laser triangulation systems.…”