Metal forming by a moving heat source is both an efficient and an economical method for forming flat metal plates into three dimensional curved shapes. However, Existing line heating systems rely heavily on empirical techniques, and require more accurate modeling. The objective of this project is to develop an automatic system of forming curved metal plates by line heating. The problem is defined as follows: Given the design of a final curved metal plate, determine the initial shape of the flat plate and the heating paths together with the heating conditions to form the curved plate by line heating.

Metal forming by a moving heat source is both an efficient and an economical method for forming flat metal plates into three dimensional curved shapes. It has been an active research topic in manufacturing, especially in shipbuilding for more than thirty years. However, up to now, no general process planning scheme for general curved shapes nor automatic control of the forming process is available. Therefore, current state-of-the-art laser or flame forming procedures are far from automatic.

The objective of this project is to develop an automatic system of forming curved metal plates by line heating. The problem is defined as follows: Given the design of a final curved metal plate, determine the initial shape of the flat plate and the heating paths together with the heating conditions to form the curved plate by line heating. Existing line heating systems rely heavily on empirical techniques, and require more accurate modeling.

We are developing the following technologies for planing the heating paths, prediction and measurement of the bending and shrinkage, and control of the heating process: (1) An optimal surface development algorithm based on differential geometry and nonlinear optimization theory; (2) A path planning algorithm for minimum-time forming; (3) An efficient FEM thermo-mechanical analysis method using rezoning technique; (4) A simplified model for real time control of the forming process.

The collaborators in this project include: Ocean Engineering Design Laboratory and Fabrication Laboratory of Massachusetts Institute of Technology.