Provided is a bending apparatus for a plate-shaped metal workpiece, including: a suction device (suction pad) configured to suck a surface of a plate-shaped metal workpiece in a removable manner; a plurality of expansion and contraction devices (servo screw jacks) each including the suction device mounted on a distal end thereof and being capable of expanding and contracting a length ranging from a proximal end thereof to the suction device; and an apparatus base (bed) on which the proximal end of each of the expansion and contraction devices is mounted. The bending apparatus is configured to form the plate-shaped metal workpiece under bending deformation by expanding and contracting the expansion and contraction devices under a state in which the suction device sucks the surface of the plate-shaped metal workpiece.

Provided is a bending apparatus for a plate-shaped metal workpiece, including: a suction device (suction pad) configured to suck a surface of a plate-shaped metal workpiece in a removable manner; a plurality of expansion and contraction devices (servo screw jacks) each including the suction device mounted on a distal end thereof and being capable of expanding and contracting a length ranging from a proximal end thereof to the suction device; and an apparatus base (bed) on which the proximal end of each of the expansion and contraction devices is mounted. The bending apparatus is configured to form the plate-shaped metal workpiece under bending deformation by expanding and contracting the expansion and contraction devices under a state in which the suction device sucks the surface of the plate-shaped metal workpiece.

A method of stretch forming a double curvature panel having corrugations or other surface features formed therein includes providing a reconfigurable forming surface defined by a flexible interpolator sheet mounted on an array of height adjustable pins, the interpolator sheet having a profiled upper surface adapted to form corrugations or other surface features in a workpiece as it is stretched over the forming surface, adjusting the height of each pin to suit the shape of the panel to be produced, placing a workpiece onto the forming surface, and stretching the workpiece over the forming surface such that the profiled upper surface of the interpolator sheet forms the desired corrugations or other surface features in the workpiece.

Apparatus and methods for forming three dimensional structures from a sheet of material of a desired medium are described. Examples described include an apparatus for folding a sheet of material to create a folded structure, the apparatus having a first and second array of creasing elements, and at least one actuator for causing relative movement of the first and second array of creasing elements from a first position to a second position.

Apparatus and methods for forming three dimensional structures from a sheet of material of a desired medium are described. Examples described include an apparatus for folding a sheet of material to create a folded structure, the apparatus having a first and second array of creasing elements, and at least one actuator for causing relative movement of the first and second array of creasing elements from a first position to a second position.

A flexible but strong universal die is disclosed, that is flexible enough to be elastically deflected into different curvatures by actuating forces and moments, while being strong enough to support the die forces and moments that it has to apply to parts to form them to the shape corresponding to its shape. A design of the die and actuation locations that makes it easy to deflect it into different constant curvatures, as well as into shapes with gradients of curvature along the length of the die, and the use of these dies for stretch roll forming are disclosed.

A flexible but strong universal die is disclosed, that is flexible enough to be elastically deflected into different curvatures by actuating forces and moments, while being strong enough to support the die forces and moments that it has to apply to parts to form them to the shape corresponding to its shape. A design of the die and actuation locations that makes it easy to deflect it into different constant curvatures, as well as into shapes with gradients of curvature along the length of the die, and the use of these dies for stretch roll forming are disclosed.

A flexible but strong universal die is disclosed, that is flexible enough to be elastically deflected into different curvatures by actuating forces and moments, while being strong enough to support the die forces and moments that it has to apply to parts to form them to the shape corresponding to its shape. A design of the die and actuation locations that makes it easy to deflect it into different constant curvatures, as well as into shapes with gradients of curvature along the length of the die, and the use of these dies for stretch roll forming are disclosed.

A flexible but strong universal die is disclosed, that is flexible enough to be elastically deflected into different curvatures by actuating forces and moments, while being strong enough to support the die forces and moments that it has to apply to parts to form them to the shape corresponding to its shape. A design of the die and actuation locations that makes it easy to deflect it into different constant curvatures, as well as into shapes with gradients of curvature along the length of the die, and the use of these dies for stretch roll forming are disclosed.

A method of making a vehicular subassembly includes a step for providing a roof header comprising a hollow member having a long axis, a short axis, and an outer surface that includes a flange. The method also includes a step of stretch bending the member such that the outer surface is substantially in tension and curved in the short axis direction. The method further includes a step of cutting a plurality of notched elements into the flange to reduce strain from the stretch bending step. In some aspects, the step of cutting can be conducted before the stretch bending to reduce strain in the header associated with the subsequent stretch bending.