Arc welding using the MetaTorch, a 2nd generation robot manufactured by Meta Machines Ltd. of Abingdon, England. The welder is mounted on a GMF robot arm. The robot's sense of sight is provided by a combination of lasers & miniature cameras, which look ahead of the welding torch to locate the precise position of the joint. This informat- ion is processed, & instructions passed to the robot arm & welding set. Consequently, the MetaTorch is able to cope with irregularities such as wear in locating pins, imperfect components & the unpredictable springback of pressed sheet metal: it can also compensate for the thermal distortions which occur during a weld.