Weld penetration control in robotic GTAW using an infrared sensor

Conference · Sat Dec 31 04:00:00 EST 1994

OSTI ID:115467

Govardhan, S M; Banerjee, P; Chin, B A ^[1]

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1. Auburn Univ., AL (United States)

This paper discusses recent developments in weld-penetration monitoring and control with the help of an infrared sensor. Recently developed signals based on infrared data were compared in order to select an efficient indicator for on-line weld-penetration control. The gradient technique developed recently uses the temperature gradient to determine penetration. This technique is a reliable indicator of penetration changes, as verified while monitoring induced-penetration changes resulting from either sudden variations in plate thickness or sulfur/aluminum concentration. The welding was performed using a gas tungsten arc welding (GTAW) torch on 0.25 in. (6.35 mm) thick AlSl 1008 steel plates. The success of this technique is bound to have a tremendous impact on the robotic welding industry. Current process control systems in robotic welding use multiple sensors. These sensors are used in combination to control torch offset, weld geometry variations, and other arc characteristics. It is easy to visualize the limitations on maneuverability caused by mounting several sensors on the welding torch. on the other hand, a single infrared sensor can be used to carry out seam tracking, detect weld geometry variations, and carry out on-line penetration control. The significance of infrared sensors is further realized when considering that these sensors can detect penetration changes from the front-side, unlike commercially available sensors that rely on back-side data acquisition.

• OSTI ID: 115467
• Report Number(s): CONF-9404233--
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
COMPUTER-AIDED MANUFACTURING
COMPUTERIZED CONTROL SYSTEMS
GAS TUNGSTEN-ARC WELDING
INFRARED SPECTRA
WELDING MACHINES