Regenerative shock absorber system has taken a step to full commercialisation
By Rob McKay | September 3, 2013
Regenerative shock absorber system GenShock has taken a step to full commercialisation through a partnership between founding US company Levant Power Corp and German vehicle equipment firm ZF Friedrichshafen.
The partnership is at the proof-of-concept stage and the technology was unlikely to appear here for a year or more,
a ZF Services Australia spokesman says.
Developed by Massachusetts Institute of Technology students who went on to form Levant, the concept, which combines fully active damping with an integrated energy recovery system, was aimed at trucks and buses at inception, with car applications a longer-term goal.
However, it appears ZF is also looking to press on with its passenger vehicle applications.
“The objective is to develop the world’s first fully active and regenerative suspension, make it ready for volume production, and introduce it to the market,” Rolf Heinz Rüger, in charge of the suspension technology business unit of ZF’s car chassis technology division, says.
“Thus, we are promoting efficient innovations that are tailored to meet global requirements.”
According to ZF, at the heart of the GenShock system is a valve arrangement, where an integrated hydraulic motor can extract power, or perform work on the damper’s fluid.
Fitted to the outside of the ZF shock absorber, the compact system contains a control unit, an electric motor and an electrohydraulic gear pump.
The electronics behind the system uses sensors that update 10,000 times a second, and can switch the system rapidly between power regeneration and consumption.
As soon as the driving situation permits, the valve system uses the swaying motion of the damper piston to recover energy, by diverting the oil via the electric pump motor.
This in turn acts as a generator and converts the kinetic energy into electricity, which is fed into the vehicle’s power supply system.
“The system works at peak performance on bumpy roads, making it ideal for country Australian driving,” ZF says.
“From a handling perspective, the system automatically reacts and adapts to driving situations, which includes hard braking and evasive manoeuvres.”
