Parallelogram articulated lattice mast for passive (self) deployment
A self-deployable mast, typically for supporting a payload. The mast has top longerons, bottom longerons, and hinge linkages that form a series of moveable parallelograms operable to fold and unfold. The mast further has springs and truss diagonals, with at least one spring and one truss diagonal associated with each of the parallelograms. The springs are operable to deploy the mast from a folded position to a deployed position. Each truss diagonal is operable to become in tension diagonally across its associated parallelogram once the mast is deployed into a final position. In other embodiments, motors may be used instead of springs.
1 . A passively deployable mast, comprising:
a series of bottom longerons;
a series of top longerons;
hinge linkages operable to attach the bottom longerons to the top longerons of adjacent sections, such that pairs of bottom longerons and top longerons form a series of parallelogram sections operable to fold and unfold as accordion pleats fold and unfold;
at least one spring associated with each parallelogram section, each spring attached diagonally from at or near one end of a top longeron to at or near an opposing end of a bottom longeron;
wherein the springs are battens configured to be placed in a loaded state by being buckled;
at least one diagonal associated with each parallelogram section;
wherein the springs are operable to deploy the mast from a folded position to a deployed position; and
wherein each diagonal is operable to become in tension diagonally in response to a force of an associated spring, which diagonal will then extend across a respective parallelogram section by the action of the springs when the mast is deployed into a final deployed position.
2 . The mast of claim 1 , wherein the diagonals are implemented with flexible wire, cable, cord, or rod.
3 . The mast of claim 1 , wherein the longerons of each section have a first side and a second side and at least one spring and one diagonal on each side.
4 . The mast of claim 1 , wherein each hinge linkage comprises a first hinge connecting two adjacent longerons, a second hinge connecting the other two adjacent longerons, and a pair of linkage arms, and wherein the second hinge is an offset hinge.
5 . A method of deploying a mast, comprising:
providing a folded mast comprising:
a series of bottom longerons;
a series of top longerons;
hinge linkages operable to attach the bottom longerons to the top longerons of adjacent sections, such that pairs of bottom longerons and top longerons form a series of parallelogram sections operable to fold and unfold as accordion pleats fold and unfold;
at least one spring associated with each parallelogram section each spring attached diagonally from at or near one end of a top longeron to at or near an opposing end of a bottom longeron;
wherein the springs are battens configured to be placed in a loaded state by being buckled;
at least one diagonal associated with each parallelogram section;
wherein the springs are operable to deploy the mast from a folded position to a deployed position; and
wherein each diagonal is operable to become in tension diagonally, in response to a force of an associated spring, which diagonal will then extend across a respective parallelogram section by the action of the springs when the mast is deployed into a final deployed position; and
actuating the mast such that the springs are operable to deploy the mast from a folded position to a deployed position, and such that each diagonal is operable to become in tension diagonally across a respective parallelogram by the action of the springs when the mast is deployed into a final position.
6 . The method of claim 5 , further comprising damping the actuating step.
7 . The method of claim 5 , wherein the diagonals are implemented with flexible wire, cable, cord, or rod.
8 . The method of claim 5 , wherein each of the pairs of bottom longerons and top longerons have a first side and a second side and at least one spring and one diagonal on each side.