TY - GEN

T1 - 3D geometry measurement of hot cylindric specimen using structured light

AU - Quentin, Lorenz

AU - Beermann, Rüdiger

AU - Pösch, Andreas

AU - Reithmeier, Eduard

AU - Kästner, Markus

N1 - Funding information: The results presented in this paper were obtained within the Collaborative Research Centre 1153 Process chain to produce hybrid high performance components by Tailored Forming in the subproject C5 Multiscale Geometry Inspection of Joining Zones. The authors would like to thank the German Research Foundation (DFG) for the financial and organisational support of this project. The authors would also like to thank Mr. Thomas Müller, Mr. Armin Dietz and Mr. Christopher Schindlbeck for their helpful input.

PY - 2017/6/26

Y1 - 2017/6/26

N2 - We present a fringe projection system to measure glowing hot hybrid components in between production processes. For this a high power green light projector, based on TI DLP technology, is used to create the highest possible contrast between fringes on the red glowing specimen. It has a resolution of 1140 x 912 pixels with a maximum frame rate of 120 images per second for fast measurement. We use a green bandpass filter (525 nm) on the camera lens to block unwanted incoming radiation from the specimen caused by self-emission. Commercial measurement standards are not calibrated for temperatures other than 20° C, so they cannot be used to validate measurement data at the required temperatures of up to 1000°C since thermal expansion invalidates the geometry specification from the calibration data sheet. In our first development we use a uniformly heated pipe made of stainless steel as a dummy specimen to examine the measured geometry data. A pyrometer measures the temperature of the pipe so the expansion can be easily calculated using the thermal expansion coefficient. Different impact and triangulation angles are investigated to identify the effects of hot ambient air on the measurement. The impact of the induced refractive index gradient is examined to check the need for pre-processing steps in the measurement routine.

AB - We present a fringe projection system to measure glowing hot hybrid components in between production processes. For this a high power green light projector, based on TI DLP technology, is used to create the highest possible contrast between fringes on the red glowing specimen. It has a resolution of 1140 x 912 pixels with a maximum frame rate of 120 images per second for fast measurement. We use a green bandpass filter (525 nm) on the camera lens to block unwanted incoming radiation from the specimen caused by self-emission. Commercial measurement standards are not calibrated for temperatures other than 20° C, so they cannot be used to validate measurement data at the required temperatures of up to 1000°C since thermal expansion invalidates the geometry specification from the calibration data sheet. In our first development we use a uniformly heated pipe made of stainless steel as a dummy specimen to examine the measured geometry data. A pyrometer measures the temperature of the pipe so the expansion can be easily calculated using the thermal expansion coefficient. Different impact and triangulation angles are investigated to identify the effects of hot ambient air on the measurement. The impact of the induced refractive index gradient is examined to check the need for pre-processing steps in the measurement routine.

KW - 3D measurement

KW - fringe projection

KW - hot measurement object

KW - inline inspection

KW - optics

KW - structured light

UR - http://www.scopus.com/inward/record.url?scp=85029147043&partnerID=8YFLogxK

U2 - 10.1117/12.2269607

DO - 10.1117/12.2269607

M3 - Conference contribution

AN - SCOPUS:85029147043

T3 - Proceedings of SPIE - The International Society for Optical Engineering

BT - Optical Measurement Systems for Industrial Inspection X

A2 - Lehmann, Peter

A2 - Goncalves, Armando Albertazzi

A2 - Osten, Wolfgang

PB - SPIE

T2 - Optical Measurement Systems for Industrial Inspection X 2017

Y2 - 26 June 2017 through 29 June 2017

ER -