High Efficiency 2 Channel Active Roll Control System

General Motors, ArvinMeritor and Pratt & Miller Engineering partnered in the development of a 2 Channel Active Roll Control (2ARC) system as a GM GATS (Global Advanced Technology Selection) project. The objective was to evaluate a 2ARC system using rotary actuators to generate auxiliary roll moment. The prototype system was designed with extra capacity so that it could be scaled back to identify ideal production roll control performance targets.

The active roll control system consists of two independently controlled active stabilizer bars. Each axle uses a brushless DC servo motor to drive a bidirectional gear pump which provides on demand hydraulic power to a single vane rotary actuator mounted in the center of the stabilizer bar. This hydraulic architecture was selected to improve overall system efficiency as compared to engine driven pump systems.

A model based systems engineering approach was taken with this development. The team established detailed vehicle performance targets using CarSim for roll couple distribution, roll gradient, and system response time. These vehicle performance requirements were cascaded to system performance requirements and eventually to component design and development. Components and subsystems were designed, built, bench tested, then checked against performance targets. The individual component test results were used to update the system model and eventually vehicle level testing was performed and correlated back to that system model.