BOMAG has released a new "Oscillation-Assisted" steering system for its BW213 series heavy tandem vibratory rollers. In asphalt paving, compacting curves is a major challenge. Traditional articulated steering requires the operator to constantly correct the steering wheel to maintain the turning radius, and the rear drum often "pushes" straight, causing the machine to "crab walk" or damage the fresh asphalt mat.
The Oscillation-Assisted system uses an "Electro-Hydraulic Differential Lock" on the rear drive motor. The system uses a gyroscope to detect the steering angle of the front articulated joint. When the operator turns the wheel, the system calculates the required speed difference between the left and right rear wheels.
The core engineering breakthrough is the "Active Torque Vectoring." Instead of mechanically braking the inner wheel, the hydraulic motor on the inner side of the rear drum reduces its speed (increasing torque), while the outer motor speeds up. This actively "twists" the rear of the machine into the turn, following the path of the front drum.
This logic creates a "Neutral Turn" effect, significantly reducing the turning radius without damaging the asphalt. The system also features an "Anti-Slip Control." If the roller is on a slope and one drum begins to slip (spin), the hydraulic differential instantly locks, transferring torque to the drum with better traction. This ensures the machine can climb steep ramps on fresh asphalt without spinning the wheels and tearing the surface. The result is a smoother, tighter compaction pattern and a 30% reduction in steering effort for the operator.
