In many shipyards, shell plates having complex curvature are formed using line heating or a combination ofline heating and cold forming. These processes are effective but labor intensive. In this paper, we describe a newsystem that plans and carries out line heating automatically. This system, called IHI-Alpha, projects the desiredcurved geometry onto the original flat plate, and calculates a heating plan which includes the travel and heatinput rate of the heating head. Once calculated, this heating plan is forwarded to a special shop workstationwhere the final curved form is then produced directly, with no iteration. This differs from the conventionalprocess which is based on operator experience plus trial-and-error.The IHI-Alpha system has been employed in the construction of a number of vessels including bulk carriers,VLCC's, and containerships. In this paper, we introduce the system, its theoretical foundation, and how it worksincluding both software and hardware aspects. Examples of its use in actual ship production are described.Finally, ideas for future development of this technology are discussed.