2015-05-042015-05-042014-10-14Constantinou, Michael C., Reinhorn, Andrei M., Sarlis, Apostolos A., Taylor, Douglas, Lee, David A., Nagarajaiah, Satish and Pasala, Dharma Theja R., "Negative stiffness device and method." Patent US8857110B2. issued 2014-10-14. Retrieved from https://hdl.handle.net/1911/80168.https://hdl.handle.net/1911/80168A negative stiffness device and method for seismic protection of a structure is described. In one embodiment, the device has an anchor frame and a movement frame laterally translatable relative to the anchor frame. The anchor frame and movement frame have respective extension portions. A linkage is pivotably connected to the extension portion of the anchor frame. A compressed spring has a first end is attached to the extension portion of the movement frame and a second end attached to the linkage. The compressed spring has a spring force. In a rest state, the compressed spring does not apply a lateral force to the movement frame. In an engaged state, the compressed spring is configured to apply a lateral force to displace the movement frame in a lateral direction of a seismic load. The spring force is amplified by the linkage when the movement frame is laterally displaced to an amplification point.14 ppengUtility patentUS8857110B2