Ammann has introduced its proprietary "Ammann Compaction Expert" (ACE) system to its new line of ART 280 articulated tandem rollers. A common issue in asphalt compaction is over-rolling, which can crush the aggregate, or under-rolling, which leaves voids. The ACE system solves this by mounting a high-precision accelerometer (an inertial measurement unit) on the drum frame.
As the roller vibrates, the drum interacts with the ground. If the material is soft, the drum movement is erratic; if the material is stiff, the drum movement is restricted and uniform. The ACE system measures this damping effect 100 times per second and calculates the "Stiffness Modulus" of the ground. This data is displayed to the operator as a color-coded heat map on the console. Green indicates target stiffness has been reached, while red indicates loose spots requiring more passes.
A critical engineering feature is the "Automatic Amplitude Adjustment." If the system detects the stiffness increasing rapidly (indicating the material is compacting well), it automatically reduces the vibration amplitude. This prevents the drum from "bouncing" on the hard surface, a phenomenon that creates ripples in the asphalt (corrugation) and damages the roller's bearings. This closed-loop control ensures uniform density across the entire mat, regardless of operator skill level.
