Jungheinrich has introduced the "Curve-Control" safety system for its ETV series 3-wheel electric forklifts. In narrow-aisle warehouses, operators often corner aggressively to save time. However, 3-wheel forklifts (which have a pivot point on the rear axle) have a higher risk of lateral tip-over during high-speed turns compared to 4-wheel models.
The Curve-Control system uses a "MEMS Gyroscope" (Micro-Electro-Mechanical System) mounted on the chassis frame. This sensor detects the "Roll Rate" (angular velocity of the chassis tilting sideways). The system is linked to the traction controller via a high-speed CAN bus. The logic operates on a "Dynamic Threshold."
If the forklift travels below 5 km/h, the system is inactive, allowing sharp turns. However, as speed increases, the system monitors the roll rate. If the operator turns the steering wheel sharply at 10 km/h, the gyroscope detects the rapid lateral acceleration. The traction controller instantly cuts the motor current and applies a small amount of regenerative braking, reducing the speed to a safe 5 km/h. This intervention is imperceptible to the operator as a "jerk," feeling instead like the machine is naturally slowing down. The system also monitors the "Castor Angle" of the rear axle. If the rear axle oscillates (shimmies), the system dampens the steering motor. This active logic prevents the "pendulum effect" that leads to tip-overs, significantly enhancing safety in multi-shift logistics operations.
