‘Smart steering’ reduces at-the-wheel effort

Driving a truck has always been the easy part of truck driving, because dealing with heavy traffic, delivery deadlines and sometimes nasty people at loading docks, inspection stations and other places can make the profession difficult.

Modern equipment like roomy, quiet cabs, powerful engines, effective HVAC systems, strong brakes, and self-shifting transmissions have made the driving part so easy that I wonder how I survived my many behind-the-wheel hours in the early 1960s. Now we have steering-assist features that go beyond power steering – “smart steering,” we call it.

None of the systems now available are meant to replace a driver’s guiding hands on the wheel. You’re still in charge but don’t need to constantly pull the wheel left or right to counter sloping or uneven pavement, crosswinds and inadvertent wandering within your lane. You still move the wheel, and an electric motor added to the steering gear adds torque to help you. Off-road travel at construction sites and on rough trails is also easier. On some systems, if you drop your hands off the wheel for more than a few seconds, you’ll hear buzzing, dinging or chirping that’ll remind you to get your hands back on the wheel and take charge.

There are several products now on the market.

Bendix Lane Keep Assist

Part of Wingman Fusion with Advanced Feature Set, the system detects when the vehicle drifts from its lane, then adds steering torque to help guide the vehicle back toward the lane’s center. If you use your turn signal while changing lanes, the system temporarily cancels. At low speeds, the active steering system aids in parking lot maneuvering and lining up a rig to a loading dock. “Active return” helps center the wheel, like after making a hard right or left turn. In fact, it’ll return the wheel to center with no input from you. “Active damping” reduces road vibrations felt through the steering wheel and improves feel.

Bendix’s active steering assistance is built on existing steering gears from Bendix’s R.H. Sheppard subsidiary.

Navistar has made Bendix’s Wingman Fusion with Advanced Feature Set standard on International LT and RH highway tractors and optional on other International models. Other truck builders may soon be offering it.

Detroit Assurance 5.0 Lane Keeping Assist

As its name says (and like the Bendix system), this works to keep the truck centered in its lane. It uses a forward-facing camera to watch lane markings and nudges the steering wheel slightly left or right as often as needed. Its camera looks for lane markings and sends signals via an electronic controller to the steering column’s motor to adjust steering. If the painted lane stripes are obscured or badly worn, or they simply disappear, like when pavement is patched or overlaid but not restriped, you’ll get an audible and visual signal to completely take over the steering. If you try to steer out of your lane without using a turn signal, it will fight you a little by nudging the wheel toward the lane’s center and sound a “burrp!” warning.

The system works best in straight-line driving or through gradual curves. You’ll have to provide more steering effort in sharper curves or on city streets, which you would want to do anyway.

Lane Keeping Assist and the rest of the Detroit Assurance driver-assist packages are available on Freightliner and Western Star trucks.

Volvo Dynamic Steering

Developed by Volvo Group engineers in Sweden, the system adds torque to reduce steering strain at low speed, both in forward and reverse. The system also makes adjustments to improve stability at road speeds when encountering crosswinds, highway crowning, soft shoulders, or emergency situations like tire failure. Dynamic Steering uses an electric motor mounted above the hydraulic steering gear to add additional torque when necessary. It receives input 2,000 times per second from sensors throughout the truck monitoring yaw rate, steering angle, wheel speed and the driver’s own actions. Optimal steering input is constantly calculated based on the conditions. After a turn, it returns the steering to center – “neutral,” Volvo calls it – and filters out vibration from rough pavement and uneven terrain.

Dynamic Steering is available on Volvo’s VNL and VNR highway tractors and VHD vocational trucks.

Mack Command Steer

The Volvo system by another name, Mack’s Command Steering offers the same advantages.

Mack sells a lot of dump and concrete mixer trucks, so the company emphasizes Command Steering’s benefits while moving over job sites and rough trails, where holes, dips and ruts can cause steering-wheel “kicks.” When such irregularities are detected, the system reacts to counter the steering force, smoothing feedback through the wheel. Under such conditions, Command Steer cuts fatigue and muscle strain by up to 85%, Mack claims. On paved roads, driver effort is cut by up to 30%. Command Steer is offered on Anthem highway tractors and Granite vocational trucks.

Personal take

In the past few years I’ve briefly driven the Bendix, Detroit and Volvo-Mack systems during sponsored equipment demonstrations. I went in skeptical – “does a driver really need this?” – but ended up liking each one.

They really do reduce steering effort, making low-speed maneuvering easier and, with the Bendix and Detroit systems, keeping trucks within their lanes. I can imagine they would be helpful while cruising on interstate highways where pavement is sloped left or right to facilitate water drainage. I can see where they improve driver comfort and safety. When they’re part of electronic active-safety systems, they use sensors, cameras and other devices, including the electric motor, that might occasionally fail. Even so, I’d rather have these features than not. LL

In This Issue: