Pub Date : 2024-09-12DOI: 10.1109/LSENS.2024.3459871
Jordan J. Wise;Lee Streeter
Time-of-flight (ToF) range imaging cameras perform full-field distance measurement, but require multiple frames to be captured sequentially in order to construct a single range image. When motion occurs during data acquisition, artifacts appear that limit the accuracy of range estimates. Analysis of these artifacts finds that they take the form of spatial waves whose frequency encodes motion information. We therefore propose a new technique for measuring motion in Time-of-Flight range imaging based on the continuous wavelet transform (CWT). Synchrosqueezing is explored as a means of improving the accuracy of velocity estimates.
{"title":"Towards Optical Flow in Time-of-Flight Range Imaging Using the Continuous Wavelet Transform","authors":"Jordan J. Wise;Lee Streeter","doi":"10.1109/LSENS.2024.3459871","DOIUrl":"https://doi.org/10.1109/LSENS.2024.3459871","url":null,"abstract":"Time-of-flight (ToF) range imaging cameras perform full-field distance measurement, but require multiple frames to be captured sequentially in order to construct a single range image. When motion occurs during data acquisition, artifacts appear that limit the accuracy of range estimates. Analysis of these artifacts finds that they take the form of spatial waves whose frequency encodes motion information. We therefore propose a new technique for measuring motion in Time-of-Flight range imaging based on the continuous wavelet transform (CWT). Synchrosqueezing is explored as a means of improving the accuracy of velocity estimates.","PeriodicalId":13014,"journal":{"name":"IEEE Sensors Letters","volume":null,"pages":null},"PeriodicalIF":2.2,"publicationDate":"2024-09-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142368460","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
This letter presents an on-chip scale crack sensor for solder joints using radio frequency signals, essential for enhancing the reliability of electronic packages. The sensor design includes a Class F power amplifier and an envelope detector, based on an equivalent circuit model of cracked solder joints. Circuit simulations reveal that as a crack initiate, a resonant dip in the S-parameter pattern appears, with the resonant frequency decreasing as the crack propagates. Leveraging the resonant dip as a prognostic factor, the sensor can accurately characterize cracks in solder joints with easy-to-handle dc output. The sensor, which provides a maximum crack length sensitivity of 0.05 GHz/ $upmu$