TWI Industrial Member Report Summary 817/2005
S J Mulligan
Background
A novel system has been developed. The 6-axis welding robot is brought to the part that has been placed at random within a working area using an autonomous robot transport vehicle (RTV). The RTV has all equipment and consumables for welding mounted on board. Four cameras above the welding cell detect global part location and orientation, and help to navigate the RTV into position for welding. This approach will allow for parts to be tack welded and robotically welded in the same location, which will reduce the need for transport of these large structures between workstations. Simulation software has been customised to allow automated generation of joint finding, following and welding process information, as well as the robot arm motion program, to automate manufacture from an electronic model of the part.
In this report, an overview of the system and its operation is presented. The innovative approach adopted in the NOMAD project places significant demands on the welding technology and the use of sensors to achieve the requirements for program automation, accuracy and weld quality. Whilst several of the challenges faced are unique to the project, much of the technology and expertise developed has wider applicability to conventional robotic manufacture, remote operations and a range of components, materials and joint designs across all industry sectors.
Objectives
- To develop strategies for applying methods of joint finding, seam tracking and adaptive arc welding process control for autonomous manufacture.
- To develop positional welding procedures using metal-cored wires for a range of joint types and material thickness, including single and multipass fillet and butt joints.