Manipulable seat bolster utilizing active material actuation
A manipulable seat bolster including an active material actuator configured to selectively cause or enable a condition, such as the geometric configuration, or position of the bolster to be modified, when the active material is activated.
1. A manipulable seat bolster adapted for use with a seat defining an exterior surface presenting a condition, and for autonomously changing the condition, said bolster comprising:
an actuator communicatively coupled to the surface, and including an active material element operable to undergo a reversible change in fundamental property when exposed to or occluded from an activation signal;
a signal source communicatively coupled to the element and operable to generate the signal, so as to activate the element,
said actuator being configured to cause or enable the condition of the surface to be modified, when the element is activated; and
a reconfigurable structure disposed within the seat, and modifiable between a plurality of structure configurations relative to the surface, wherein the condition is the geometric configuration of the surface, and each of the structure configurations causes the surface to present a different geometric configuration;
said actuator being drivenly coupled to the structure, and operable to modify the structure so as to achieve one of the configurations, when the element is activated,
wherein the actuator further includes an overload protector connected to the element opposite the structure, and configured to present a secondary work output path, when the element is activated and the structure is unable to be moved.
2. The bolster as claimed in claim 1 , wherein the actuator further includes a stored energy element communicatively coupled to the active material element, the stored energy element is operable to release stored energy when the active material element is activated, and configured to change the condition, as a result of releasing the energy.
3. The bolster as claimed in claim 1 , further comprising:
at least one sensor communicatively coupled to the source, operable to detect a condition, and configured to selectively cause the source to activate the material element, when the condition is detected.
4. The bolster as claimed in claim 3 , wherein the condition is an actual or imminent crash event.
5. The bolster as claimed in claim 3 , wherein the sensor is a load cell operably positioned relative to the surface, and the condition is a minimum force applied to the surface.
6. The bolster as claimed in claim 3 , wherein the condition is a minimum yaw or lateral acceleration rate.
7. The bolster as claimed in claim 1 , wherein the element is a shape memory alloy wire.
8. The bolster as claimed in claim 1 , further comprising:
a return mechanism drivenly coupled to the structure antagonistically to the actuator, and producing a biasing force less than the actuation force, such that the mechanism causes the structure to move to the first position when the element is deactivated and allows the actuator to drive the structure to the second position when the element is activated.
9. The bolster as claimed in claim 8 , wherein the return mechanism is selected from the group consisting essentially of compression, extension, leaf, pneumatic/hydraulic and torsion springs, shape memory alloy wires operating in the martensitic mode, and shape memory alloy wires operating in the superelastic mode.
10. A manipulable seat bolster adapted for use with a seat defining an exterior surface, and for changing the geometric configuration of the surface, said bolster comprising:
a moveable structure disposed within the seat, and moveable between a plurality of positions relative to the surface, wherein each of said positions causes the surface to present a different geometric configuration; and
a locking mechanism operable to selectively engage, so as to prevent motion in at least one direction by, the structure in each of said plurality of positions, and including an active material element operable to undergo a reversible change in fundamental property when exposed to or occluded from an activation signal,
said element being configured to cause the mechanism to move to one of engaged and disengaged conditions, when activated, and said structure and mechanism being cooperatively configured such that the structure is moveable in the direction only when the mechanism is in the disengaged condition,
wherein the structure defines a pivot axis, and the mechanism includes a ratchet concentrically aligned with the axis and fixedly coupled to the structure, and a pawl configured to selectively engage the ratchet so as to prevent rotation.
11. The bolster as claimed in claim 10 , wherein the structure is causable to rotate about a rotation axis and defines a plurality of sloped teeth corresponding to the plurality of positions, and each of said teeth are operable to slidingly engage the mechanism in a first direction of rotation and catch the mechanism in the other direction of rotation, so as to enable relative rotation only in the first direction and hold the structure in a selected one of the positions, when the mechanism is in the engaged condition.