Developing a flexible sheet forming system

Abstract Since the inception of sheet metal forming, matched tooling has been used for forming complex three-dimensional part shapes and, whilst it is economical in high-volume production applications, the lengthy and costly die development period has precluded the use of this technology for small lot production. In order to alleviate these two interrelated problems and make small lot production of three-dimensional parts economically viable, a flexible sheet forming system consisting of novel die development algorithms and new forming procedures has been developed and tested experimentally. This flexible sheet forming system combines an iterative control law, re-usable dies fashioned from low melting point alloys, automatic part measurements and CNC die machining methods to form a digital, closed-loop, die synthesis control system. This closed-loop controlled, flexible sheet forming system is capable of producing the desired part geometry in a fraction of the time required by previous die development methods, typically 2–4 days, thus effecting a considerable savings over previous methods. Furthermore, this prototyping or small batch technology can be combined easily with real-time binder force control and offered over the internet to multiple users as part of a sheet metal design and fabrication center, creating a new, inexpensive, rapid prototyping technology that has not previously been available.