Remotely Controlled Double-Trailer Rig Parks Precisely at ZF Demo

July 10, 2014

By Tom Berg

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The tractor’s steering and movement are remotely controlled by a man with special app on a tablet computer. It sends the pup trailer in the proper path, and the semitrailer and tractor follow along, guided by the ZF app’s computations. Photo: ZF Freidrichshafen AG
The tractor’s steering and movement are remotely controlled by a man with special app on a tablet computer. It sends the pup trailer in the proper path, and the semitrailer and tractor follow along, guided by the ZF app’s computations. Photo: ZF Freidrichshafen AG

AACHEN, GERMANY -- The ZF Innovation Truck crept backwards as its second trailer, a tandem-axle pup hitched by drawbar to a semitrailer just ahead, moved along a row of orange cones on the vehicle’s blind side. The tractor and semitrailer followed and the entire rig was parallel-parked smartly.

This is a tricky maneuver involving two pivot points that not many drivers can accomplish, so the guy behind the steering wheel of the DAF tractor must’ve been pretty sharp. Not necessarily, because that pup was being aimed by a second man using a tablet computer with a special application that steered the tractor in response to electronic instructions.

Through its fifth wheel, the reversing tractor nudged the nose of the semitrailer left or right, moving its rear end in an opposite direction, causing the front of the drawbar to swing slightly and thus steer the pup trailer. No steerable axles were used.

The tractor’s driver was not touching the wheel; the power steering system’s electric motor was getting wireless orders from the tablet, whose app was computing the inputs needed by the semitrailer’s nose and the pup’s draw bar so the pup would move in the correct direction.

In fact, the tractor didn’t need anyone behind the wheel, and its driver could’ve been the guy with the tablet, walking along with the rig as he backed it into the parking space using the app on the tablet or his smart phone.

He could switch its automated transmission from reverse to neutral and drive, and move the truck fore and aft as required to complete the maneuver.

The value in this electronic remote control is efficiency -- backing and parking a rig quickly and precisely so it could be loaded and unloaded without delay, then get back on the road, ZF representatives told a troop of reporters from Europe and North America this week. In actual service, the driver would have the tablet and tell the pup trailer where to go.

This exercise, at a test track near Aachen in west-central Germany, for now is mostly theoretical, as combinations like this are seldom used in Europe and no customer has asked for such capabilities, company reps said. ZF’s purpose is to suggest that rigs with cargo capacity greater than current tractor-trailers are entirely feasible.

And the demonstration showed what the creative engineers employed by ZF Friedrichshafen AG, which bills itself as a technology company, are capable of, company officials said. It was among a number of current and future products for commercial trucks and buses showcased by ZF at the press event on Wednesday.

Transmission Coming to North America?

ZF is a developer and maker of chassis and drivetrain components for vehicle builders around the world, particularly in Europe, Asia and South America. It has 37,000 employees and 120 manufacturing plants.

In North America, ZF supplies steering parts and automatic transmissions for cars and light trucks, mostly models from Chrysler Group. It operates a plant in the Carolinas.

Its AS Tronic automated manual transmissions are used in heavy and medium-duty trucks and large buses built and sold in overseas markets. Some of them were shown and driven by reporters at the event.

Also shown were self-steering rear axles on trucks and a trailer; an independent front suspension with rack-and-pinion steering, and a high-performance cab suspension.

A number of years ago, ZF’s AS Tronic was sold briefly in North America by a joint venture with Meritor Inc., which called the 12-speed self-shifting gearbox FreedomLine. The product was withdrawn as a result of an anti-trust battle with Eaton Corp., whom Meritor sued.

In a protracted series of filings and a trial in federal court, followed by appeals, Meritor won the case and, just recently, a $500 million judgment. Presumably, it could return to the transmission business, but probably won’t.

ZF is not likely to return to North America with the AS Tronic, said spokesman Bryan Johnson. But it might send the TraXon, its next-generation automated transmission also displayed at the press event.

TraXon uses a modular design that allows it to function with an automated dry clutch; with dual clutches so it acts as a powershift transmission; with a torque converter, for use in vocational trucks and transit buses; or as part of an electric-drive hybrid.

Sales of TraXon will begin in Europe and perhaps elsewhere next year, ZF officials said.

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  1. 1. Train Driver [ July 11, 2014 @ 06:45AM ]

    unless you have backed up doubles before you can not fully appreciate the skill involved here.
    I drove gravel trains in Michigan for a few years.
    semi trailer pulling a pup with a steerable dolly
    the closest thing i can equate it to is trying to back up two grain wagons with a tractor.


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