generate from magnet

Regenerative shock absorbers(magnetostatice)
The regenerative electromagnetic shock absorber uses an electromagnetic linear generator to convert variable frequency, repetitive intermittent linear displacement motion to useful electrical power. The regenerative electromagnetic shock absorber technology was developed by Tufts University engineering professor emeritus Ronald Goldner and colleague Peter Zerigian within the School of Engineering and received additional support in subsequent years from Argonne National Laboratory. While Goldner and Zerigian have patented the idea, it also appears that an almost identical concept was developed in the same period by David Oxenreiderof Boiling Springs, PA, a design which took out Second Prize in the 2005 Emhart "Create the Future" Design Contest.


How it works
A conventional automotive shock absorber dampens suspension movement to produce a controlled action that keeps the tire firmly on the road. This is done by converting the kinetic energy into heat energy, which is then absorbed by the shock’s oil. The Power-Generating Shock Absorber converts this kinetic energy into electricity instead of heat through the use of a linear electric motor. The electricity generated by each PGSA can then be combined with electricity from other power generation systems (e.g. regenerative braking) and stored in the vehicle’s batteries.
The motor is usually a cylindrical 3-phase brushless permanent magnet linear electric motor that is sometimes referred to as a ServoRam. Early ServoRams were developed in the 1990s to replace hydraulic rams in entertainment motion simulators. Bose have also developed an Active Suspension System that uses linear stepper motors to replace standard shocks/springs. Bose claim they have been working on the software (algorithm as they call it) for 24 years (since 1980). The difference between the Bose system and power generating or regenerative shock absorbers is that the later retain standard coil springs to suspend the static load of the vehicle while Bose have deleted springs altogether.
Linear motors as replacement ‘shock absorbers’ are a much cheaper solution with more regenerative potential and have enormous potential in motorsport, where shock absorbers could be constantly variable. An electromagnetic shock absorber could be tuned to respond to virtually any input. With regenerative shock absorbers connected to a microprocessor system with any number of inputs such as on-chip gyro, accelerometer, ride height and steering angle a 4-shock system can actively control a vehicles pitch, roll and yaw.
Since the technology actively uses the weight of a vehicle for energy recovery, it could help speed the expansion of the hybrid and battery electric vehicle market from cars to vehicles of greater size, weight and payloads, such as SUVs, pickup and delivery trucks, mail trucks, school and city buses and other light and medium duty trucks