Patent ID: 8354608

Claim:
A method for control of a fusion welding process by maintaining a controlled weld pool volume, comprising: (a) generating a weld pool using a welding machine tool having a plurality of process variable settings, (b) making a thermal measurement of a weld pool using a thermal sensor, (c) using a thermal inverse model to predict the thermal response of the weld pool to the plurality of process variable settings, wherein the thermal inverse model comprises a reduced order thermal model that runs forwards in time together with an optimization method that changes parameters in the reduced order thermal model until the reduced order thermal model predictions match a set of observed thermal profiles from the welding process; (d) comparing the predicted thermal response of the weld pool to the thermal measurement of the weld pool, and (e) changing at least one process variable setting of the welding machine tool in response to the comparison of the predicted thermal response and the thermal measurement of the weld pool.