Volvo Trucks introduces dynamic steering system combining hydraulic power steering with electric motor
|Volvo Dynamic Steering. Click to enlarge.|
Volvo Trucks is introducing Volvo Dynamic Steering, which combines conventional hydraulic power-steering with an electronically-regulated electric motor fitted to the steering gear. The result is precise steering that gives a truck driver a safer and more comfortable working environment.
An electronically-controlled electric motor attached to the steering shaft is the technological innovation in Volvo Dynamic Steering. The electric motor, which works together with the truck’s hydraulic power steering, has a maximum of 25 N·m (18 lb-ft) of torque and is regulated thousands of times per second by the electronic control unit.
The task of the electric motor is to deliver perfect steering feel for every single moment of operation. For instance, the system’s sensors note that the driver wants to drive straight ahead and automatically ensures that no interference from the road surface is allowed to filter up through the steering wheel.
At low speeds the electric motor’s assistance makes the truck exceptionally easy to steer. Even a heavily-loaded construction truck operating off-road on a rough surface can be steered without the slightest effort. Truck drivers who’ve tested the system during the development process have all been highly impressed.—Gustav Neander, project manager for Volvo Dynamic Steering
The system offers four main benefits, Volvo says:
At low speeds, the electric motor takes over the work from the driver’s muscles. Instead, the driver can relax and steer without having to strain his or her shoulders and arms. Volvo Dynamic Steering also centers automatically even when reversing.
Irregularities in the road surface, such as cracks and pot-holes, are dampened by the system. This means that the steering feels more stable since the driver does not have to compensate with constant minor adjustments of the steering wheel.
On the highway this precise control leads to increased directional stability. The dynamic steering system eliminates virtually all small steering wheel movements that are unavoidable on today’s roads.
A steeply-cambered road surface or a side wind is quickly detected by the self-learning system, which automatically compensates so that the driver can steer straight ahead without having to tug the steering wheel to counteract any sideways movement.
Volvo says that Dynamic Steering addresses the most frequent occupational injuries suffered by heavy goods vehicle drivers. Official figures from the Swedish Work Environment Authority reveal that truck drivers are over-represented in occupational injury statistics.