Abstract: Embodiments of this disclosure are directed to devices that allow for adjusting of device parameters in a manner that does not involve power dissipation in an essential way. Thus, power demands when such devices are used in applications can be insignificant. This applies to both springs and inerters, which constitute basic lossless building blocks of mechanical device systems, and are analogues of inductors and capacitors in electrical circuits. Embodiments of this disclosure are also directed to a lossless adjustable 2-port transformer, and realization of mechanical translational and rotary transformers are set forth in the following. Embodiments of this disclosure allow for reduction of power demands in adjusting device parameters.

Abstract: A method of optimizing electricity use from an electric grid is disclosed. The method includes formulating a target load using a cost function for the electric grid, broadcasting a cost signal to the electric device based on the target load, receiving a charging profile from the electric device based on the cost signal, aggregating a demand profile for the electricity use based on the charging profile, determining an updated cost signal based on the demand profile, and broadcasting the updated cost signal to another electric device. The electric device is chargeable electric device, such as a plug-in electric vehicle (PEV). The electric device determines the charging profile only once based on the cost signal, and is charged at maximum power.

Abstract: A method of optimizing electricity use from an electric grid is disclosed. The method includes formulating a target load using a cost function for the electric grid, broadcasting a cost signal to the electric device based on the target load, receiving a charging profile from the electric device based on the cost signal, aggregating a demand profile for the electricity use based on the charging profile, determining an updated cost signal based on the demand profile, and broadcasting the updated cost signal to another electric device. The electric device is chargeable electric device, such as a plug-in electric vehicle (PEV). The electric device determines the charging profile only once based on the cost signal, and is charged at maximum power.

Abstract: In order to meet the demands of simplicity and reliability in active control systems for flexible structures, an inexpensive active truss element and control law has been developed. A decentralized switching control law is used along with a compressible fluid in the truss element in order to dissipate energy during the motion of the structure. However, the energy is not absorbed in the same manner as a conventional viscous damper. The truss element retains its maximum stiffness, but has a resettable nominal unstressed length. Energy is absorbed in the working fluid of the truss element through heat transfer to the environment when the nominal length is reset at the proper switching times. The control law is insensitive to changes in structural parameters such as mass, stiffness, and damping.