Noncontact ultrasonic sensing for seam tracking in arc welding processes

S. B. Zhang, Y. M. Zhang

Research output: Contribution to journalArticlepeer-review

18 Scopus citations


A novel seam tracking technology based on high frequency ultrasound is developed in order to achieve high accuracy in weld seam identification. The transmission efficiency of the ultrasound is critical for obtaining a sufficient echo amplitude. Since the transmission efficiency is determined by the difference in impedance between the piezoelectric ceramic and air, match layers are designed to optimize the transmission efficiency by matching impedance. Since the air impedance depends on the density and velocity of the ultrasound, which both depend on the temperature, the optimization has been done for a wide bandwidth. Also, the receiving circuit is designed so that its resonance frequency matches the frequency of the ultrasound. As a result, the sensitivity of the noncontact ultrasonic sensor is improved 80-fold. By properly designing the focal length of the transducer, a high resolution ultrasound beam, 0.5 mm in diameter, is achieved. Based on the proposed sensing technology, a noncontact seam tracking system has been developed. Applications of the developed system in gas tungsten arc welding (GTAW) and C02 gas metal arc welding (GMAW) processes show that a tracking accuracy of 0.5 mm is guaranteed despite the arc light, spatter, high temperature, joint configuration, small gap, etc.

Original languageEnglish
Pages (from-to)600-608
Number of pages9
JournalJournal of Manufacturing Science and Engineering, Transactions of the ASME
Issue number3
StatePublished - Aug 1998

ASJC Scopus subject areas

  • Control and Systems Engineering
  • Mechanical Engineering
  • Computer Science Applications
  • Industrial and Manufacturing Engineering


Dive into the research topics of 'Noncontact ultrasonic sensing for seam tracking in arc welding processes'. Together they form a unique fingerprint.

Cite this