Advances in ride control Getting up-to-speed on electronic suspension control By Mike Mavrigian
Magneto-rheological damper
Gateway control unit/CAN bus
Switch
Control unit with control algorithm
Status indicator on dash
Travel sensors
Example of the magneto-rheological (MR) fuid system shown here on an Audi TT.
34 | January/February 2014
Courtesy of Audi of America
O
nce upon a time, ride control simply referred to providing a vehicle with a comfortable driving experience while limiting excess body roll. This was primarily addressed by the automakers by the selection of the appropriate springs, shock absorbers that would dampen spring movement and anti-roll bars that somewhat tamed, or limited, excess body lean during turns or steering maneuvers. A properly controlled suspension system, or “ride control” system, is enlisted with the responsibilities of controlling spring and suspension movement, enhancing tire life, providing consistent and predictable handling and braking, maintaining wheel alignment, and minimizing excessive body lean and body dive.
It should come as no surprise that with today’s ever-advancing and ever-encroaching computer control and management systems, the once mechanically operated suspension systems have now entered the management-by-ECU realm. Generically, suspension systems that are “controlled” or “managed” by means of electronic aid may be referred to as “adaptive” or “active” suspensions. Examples of vehicles that feature some sort of adaptive suspension system include such models as the 2008 Lexus GS350 with its adaptive ride control (this uses small electric motors attached to the upper tips of the shock rods to rotate the rods, changing damping characteristics much in the way that was once handled by manual adjustment on some adjustable performance shocks), 2002 and later Cadillac STS, GMC
