ZF's semi-active Continuous Damping Control (CDC) system solved the problem of these conflicting objectives decades ago. Our semi-active damping system went into volume production for passenger cars in 1997. Using the signals from two wheel and body sensors for each spatial axis, plus additional information such as vehicle speed, lateral acceleration and steering angle stored in a control unit, the system continuously monitors driving conditions and calculates the optimum damping force for each wheel. The damper has either one or two electronically controlled solenoid valves that can change the oil flow in milliseconds to adjust the damping hardness. ZF chassis expert Dr. Elbers explains: “sMOTION takes things a step further. Using the basic design of our tried-and-tested CDC, we developed a damper that can actively pull up or push down the wheel.”
Until now, vehicle body excitation was tolerated or even desirable to a certain degree so as to give drivers perceptible feedback on conditions. But in highly automated or autonomous vehicles, all the occupants become passengers. And in that scenario, every vibration, impact, roll or pitch simply stops people from reading or working. This causes dispositions known as motion sickness, making these activities impossible,” says Dr. Elbers. “This effect is amplified by innovative seat arrangements in which driver and passengers may no longer have a view in the direction of travel.” A remedy can only be found in an active chassis. sMOTION is a ZF solution for the future that is already improving driving comfort today. Practically undisturbed by the driving process, passengers can spend their travel time working or relaxing.