Land Rover’s ACE
LAND Rover’s Discovery II (1998) offered ‘active’ sway bars, called Active Cornering Enhancement (ACE), on some models. ACE used a high-volume, high-pressure pump and hydraulic rams, placed between the chassis and the sway bars, to tension or relax the sway bars depending on whether the vehicle was travelling straight or around a corner.
When travelling straight, the hydraulic rams placed no resistance on the ends of the bars, which gave the effect of not having a rollbar at all. Once the vehicle entered a corner the hydraulic rams tensioned the sway bars by an amount proportional to the vehicle’s lateral acceleration, as measured by two accelerometers. In essence, ACE is a more complex (pump-driven) version of Toyota’s KDSS system. It came out nearly 10 years before KDSS first appeared on the then-new Land Cruiser 200, in 2007.