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Prediction is a dangerous game. As we have compiled this

millennium issue the most enjoyable aspect has been looking at past editions of CM to find out their predictions. Some have been startlingly accurate, but many have been hilariously off-beam. So this is a round-up of the technologies that could he making their way into trucks in the first few years of the next century. If you are laughing at this article in 2050 (and perhaps enjoying a cold Martini teleported direct from the American Bar at the Savoy) then allow us a little journalistic licence...

Toby Clark looks forward.

ith safety legislation becoming ever more draconian, and automation continuing apace, we must ask whether there will there be any truck dri vers in a few years' time. Mercedes-Benz has considered this, and has already demonstrated a prototype Actros tractive unit that can drive around a yard or dock side on its own. This vehicle, fitted with an automated Telligent gearbox, electronically

controlled brakes and electrically powered steering, can navigate to an accuracy of 25mm using a combination of two GPS (Global Positioning System) satellite networks. It is quite eerie to see the artic set off, negotiate a slalom of cones, steer around a group of other trucks and park in its original position, all without the aid of a driver

IN THE DRIVER'S SEAT

The Mercedes vehicle is clearly not sophisticated enough to take to a crowded road, with the myriad hazards of pedestrians, junctions and other vehicles, but the company is doubtless working on that (see "Size matters", page 70).

In the meantime, drivers can fight back. By becoming more skilled and more flexible, they may become indispensable—after all, it has become fashionable to refer to drivers as "asset managers" in charge of expensive capital goods (and the brand identity that goes with them). Training is an important part of this, and companies such as Thomson-CSF have demonstrated practical, simulator-based systems. Why risk an

0 expensive truck (and an even more precious driver) when you can teach winter driving techniques in the simulator?

Once you have found your valuable, highly trained driver, it makes sense to keep him. Driver retention has become an acute problem in the US—some fleets are suffering annual turnover rates of more than ro and operators want ever more comfortable trucks. Some new models incorporate cabins with room for a group of drivers to congregate and watch TV Things are unlikely to go that far in Europe (overall truck length restrictions make sure of that) but there is an undoubted trend for cabs to become more comfortable. Solo-driver layouts, like those introduced by Scania and Renault, look set to take off, and even panel vans have become noticeably more pleasant to drive.

One of the most important factors in driver comfort and fatigue is noise: high sound levels are simply exhausting, and manufacturers have done much to reduce in-cab noise. Stateof-the-art vehicles such as the Daf 95XF are quieter than most luxury cars, and our own tests indicate that a modem 40-tonner is about half as noisy inside as a truck of lip years ago. Electronic and hydraulic links have replaced mechanical linkages, and cut the number of paths that noise can take. But the next stage is likely to be active noise reduction. This would involve building flat panels into the cab which would radiate sound in the opposite phase to the offending sound to cancel it out. Noise cancellation has already been used in aircraft, and will become easier and cheaper, although the continually varying sounds within a truck cab are more challenging to deal with than the drone of an airliner.

The basic structure of a truck cab has changed little in 20 years, although improved moulding compounds and techniques have transformed the quality of limited-production "plastic" cabs (such as ERF's EC range).

Cab safety is not just about strength. The design of the driving position is equally important, and those nasty protruding steering wheels will have to go. Daimler-Benz has demonstrated an Actros with joystick control—in fact, a "sidestick" on each arm of the driver's seat. Each stick has full control of acceleration, braking and steering, using the same technology as the driverless Actros, and there is no wheel, steering column or pedals to injure the driver if the vehicle is in a crash. Driving this way is strange to begin with, although it is undeniably comfortable, and it feels very zist century!

ENGINES

The reciprocating internal-combustion engine—in particular, the diesel engine—is unlikely to be supplanted in heavy-truck applications for a few years yet, for good reasons. First, it is relatively powerful, in terms of specific power output for a given weight or size of engine (measured in kW per tonne, or kW per M3 volume). Second, derv, especially, gives excellent range for a given volume of fuel. Third, it is a known technology with an enormous infrastructure of facilities, services and experience behind it.

The main challenges to diesel are gaspowered engines, hybrid drives and fuel cell systems. Each is promising in its own way, but diesel engines have a fair bit of room for improvement and the key word here is control.

Even now, emissions are being cut by more precise fuel metering, higher injection pressures, low-sulphur fuel and catalytic converters. MAN has introduced Euro-3 engines

with exhaust gas recirculation (EGR), and several manufacturers are working on exhaust after-treatment systems ready for Euro-4 in 2005 and beyond. But these systems may need a reagent chemical such as urea to reduce NOx emissions to the required levels, which means a further change in infrastructure—perhaps then some other technology will come to the fore.

For example, electronic control can be applied to more aspects of the fuelling than ever before, as shown by Caterpillar with its latest HEUI -B electronic unit injectors. These are actuated by a high-pressure hydraulic system, controlled using a couple of solenoid valves, to give variable injection pressures and flow rates, pre-injection and variable shut-off. All these characteristics—a total of zz variables—can be optimised according to engine speed, load and accelerator position.

Once there is completely variable injection timing, it would be good to be able to control valve timing. Mechanical systems have come and gone, but the way forward seems to be a hydraulically actuated valve-train. This would use some of the same technology as HEUIit requires no great breakthrough in engineering—and it is known that both Caterpillar and Jacobs are working on such a system. Under electronic control, the hydraulic valve-train can vary the opening and closing of inlet and exhaust valves independently, allowing a cylinder to freewheel under light load or turning it into a highly effective compression brake on overrun. In normal running, the

engine will be able to P D deliver high torque and efficiency at any point in the rev range.

Another idea for improving the flexibility of a turbo-diesel is the variable-geometry turbocharging system, as demonstrated in production by iveco's Cursor range of engines.

The idea is to keep the turbocharger operating at peak efficiency even when engine revs are low. But there is a more novel way to achieve this—the electric turbocharger. Most engineers dismiss this idea as snake oil. Where is the efficiency gain in powering a turbocharger impeller electrically, when the losses through the electrical system will be crippling?

Again, the key is control: by powering the turbine at low engine speeds, engine response and thermodynamic efficiency remain high; at high engine speeds (when a waste-gate or a variable-geometry housing might be used to limit turbine speed and boost pressure) the turbine can be slowed using dynamic braking. This would have the welcome effect of acting as a high-speed generator, producing electric ity to charge the batteries. BMW is the first manufacturer to apply this system to a production car---its new V8 turbo-diesel—although Turbodyne Technologies of California has been producing a more basic aftermarket kit for heavy vehicles (mainly buses) for years. Neither of these, however, incorporates the charging function.

One of the main objections to alternative fuels in heavy vehicles is their sheer inefficiency—it is a fact that an Ottocycle (spark-ignition) engine, with its relatively low compression ratio, cannot be as thermally efficient as a diesel.

But there is a way to enable even natural gas (methane) to burn without a spark plug: Caterpillar's dual-fuel engines are basically diesel units which start on derv, then introduce increasing proportions of gas into the mixture until it is 8o% oil and 2o% gas, and can be ignited simply by compression.

Current models have been criticised on grounds of driveability, but the ultimate aim must be to reduce the requirement for fuel oil to the minimum, perhaps with a tank that is simply replenished along with the engine oil.

Fuel cells convert chemical fuel directly into electricity, and are regarded as the "clean" power source of the future. A hydrogen/air fuel cell, for example, produces only pure water from its exhaust. The problem with hydrogen is its lack of density—as the lightest element it requires bulky storage tanks or expensive, high-pressure tanks. An alternative is to use metal hydrides, with hydrogen stored in a light metallic "sponge".

But there is another problem, in that hydrogen has to be man-made. Although some can be produced by "pyrolysing" organic waste, and some by electrolysis of water using wave or wind energy, it would still be difficult to meet a significant part of the world's transport energy needs. Several manufacturers are looking at fuel cells that run on methanol, ethanol or other liquid fuels, Though not quite as clean as hydrogen, these fuels could be easily made from plant matter, and offer energy densities similar to that of diesel fuel.

Hybrid power looks to be the most efficient use of present technology—combining an internal-combustion or gas-turbine power unit with an electric drive system, usually supplemented with batteries. This means complexity and weight, but ingenious solutions have been proposed—for instance, building a

traction motor into the flywheel and using it as a combined starter/generator, or a more radical solution which combines a highly efficient constant-speed engine with hub. mounted motors. This revolution is now upon us, as the first practical hybrid vehicles have entered production (see the Toyota Prius driving impressions on page 68).

ELECTRONICS

With electronic control seeping into every aspect of the truck, it is becoming possible to link systems together for greater effect: combine anti-lock braking (ABS) with engine management and there is the potential for traction control and anti-skid systems (ASR). Add a yaw sensor, and it is possible to create automatic stability control (ASC), braking individual wheels to keep the vehicle in a straight line. An electronic braking controller (EBC) linked to acceleration sensors can "learn" the weight of a trailer, adjusting brake predominance to suit.

Sophisticated cruM control, retarders and automated gearboxes (like ZF's AS-Ironic and Eaton's AutoShift) will add more complexity, while the future will bring active suspension, collision sensing, driver wakefulness detection and much more.

Linking these devices requires a "bus"

system such as CAN (Controller Area Network). This standard is working well so far, but next-generation trucks may have a more sophisticated network, rather like a PC, with different components running under the same "operating system".

All these systems can create problems: first there is interference—each digital device emits electronic "noise" which can disrupt other devices, and much design effort has to go into making systems compatible. Next, there is the sheer strain on the vehicle's electrical system. Car manufacturers are working on a standard for high-voltage (at least 36V DC) electrical circuits, and an equivalent standard will be needed for trucks—higher voltages mean lower current, and will enable lighter wiring harnesses to be used.

If you think that all these systems are at the cutting edge of technology, just look at the CM report that Citroen had patented a radarcontrolled active suspension system in February 5962. Clearly the automotive industry has never been short of ideas, and relatively cheap electronics have made it easier than ever to put them into practice. III Many of the new technologies in the automotive world have a tendency to stay tantalisingly out of reach. But one manufacturer. Toyota, already has its view of the future on the road. CM has driven the Prius petrol/electric car on British roads, and was impressed,

Its hybrid technology uses a more-or-less conventional 1.5-litre 57hp petrol engine to share the driving with a 30kW electric motor. Once the system is at normal operating

temperature the electric motor provides drive through the continuously variable transmission (CVT) until 20km/h, when the petrol engine takes over. The transition from electric to petrol power is seamless, only noticeable by reference to the power flow display on the dash. This also indicates the status of the key to the Toyota's success—the regenerative charging system. Surplus power on the over-run or under braking is

diverted by the electronics to the metal hydride batteries, which consequently never need external charging. In the Prius, the batteries occupy about 80mm of the space between the rear seat backrest and the boot.

The petrol engine is not entirely conventional, though. Operating as it does in a relatively narrow speed range, and with backup power provided by the motor, it can be tuned with the compromise much nearer to economy than flexibility. Variable valve timing and a compression ratio of 13.51 (an amazingly high figure for a roadgoing petrol engine) combine to create a highly efficient unit.

Although the Pries tested was a home market example with a chassis tuned to Japanese tastes, and performance optimised for 100km/h cruising, it was perfectly usable on UK roads. Performance was a match for any comparable family saloon, mixing it happily with town and motorway traffic alike. The only differences were the uncanny smoothness and the fact that each gallon of unleaded could propel the car for up to 80 miles (128km). And

unlike some vehicles of the future, it needed no allowances to be made. The Prius has been on sale in Japan for two years and now sells about 2,000 units a month.

A "Europeanised" version goes on sale in the UK soon, and Honda has its own hybrid car ready for production, while other applications are being developed in Japan.

GemId the petrol-electric or diesel-electric hybrid be the ideal urban delivery vehicle for the new century?

by Colin Barnett Far left: Prius' hybrid driveline is little more bulky than a conventional unit. Above: A dashboard display shows the flow of energy from the engine through the batteries to the electric motor.

Railways are environmentally friendly—wile can argue with that? Trains, travelling at moderate speeds on gently sloping, low-friction tracks, are an energy-efficient way to transport large loads over long distances. But, unlike trucks, they are inflexible and they involve enormous capital cost. So designers are looking at ways to give trucks some of the advantages of trains—and the most obvious of these is size.

Trailer builder Don-Bur has designed a triaxle steering bogie to improve the manoeuvrability of extra-long semi-trailers.

The system was demonstrated on a scale model at this year's CV Show, and the firm is building an 18.65m trailer to prove the concept; this should have the turning circle of a 16.5m trailer, while staying within overall drawbar lengths.

A good example of thinking big is Scania's latest concept vehicle, said to be a vision of road transport in 2010. ft is a development of the Seania/Krone concept vehicle seen at the Hanover Show in 1998, and shows how a 28m, 60-tonne combination can be as manoeuvrable as a conventional 16.5m antic.

Its sheer length makes it aerodynamically efficient, and this is helped by sideskirts, wheelmounted mudguards on the steering axles and "boat-tail" flaps which pop out at speed to smooth the airflow. This last feature alone is said to reduce air drag by 10%.

Other features of the Scania concept include single tyres on all axles and air suspension to keep axle loadings down to eight tonnes. Four of the eight axles are steered: the first and third prime mover axles, one dolly axle and the rearmost trailer axle. Less convincing features include the vestigial "bonnet" at the front— apparently there to help aerodynamics and to act as a crumple zone—and the "bellows" between prime mover and trailer.

The problem, as ever, will be public opinion: the thought of "juggernauts" that are 50% heavier and longer than the largest trucks at present is enough to send any transport minister into a cold sweat.

So the way forward may be by stealth: instead of larger individual trucks, what about a "train" of trucks?

Mercedes-Benz is at the forefront of this idea, with an "electronic drawbar" system known as Promote-Chauffeur. The system lets one artic follow another automatically along a motorway, controlling speed and steering to maintain a safe distance. instantaneously when the lead vehicle is about to brake, the minimum distance between vehicles can be reduced (from around 20m to as little as 15m when running at 130km/h). This, in turn, reduces air turbulence and drag between the trucks and reduces fuel consumption by as much as 15%. Even the lead vehicle, which bears the brunt of the wind, will save some fuel.

Legislation does not permit such systems at the moment—and the thought of "driverless" trucks may be even more frightening than larger trucks—but the benefits of such a system are clear, from reducing driver fatigue to increasing traffic density.

HE NUMBERS CAME _

• With information technology invading every aspect of road haulage, operators and customers are able to look at efficiency in ever more sophisticated ways—miles per gallon and pallets per load are not enough.

Measuring the performance of the truck may not be all that useful: it Is the cost of operation that matters. Operators are starting to use more advanced assessment tools, modelling truck usage in terms of turnround times, volume usage and driver effectiveness in order to make the best use of what they already have. Combined tracking, engine monitoring and fleet management—as used in Charterway's "pay as you drive" contract-hire system—enable precise cost management.

Environmental legislation is likely to put the emphasis on the whole-life costs of vehicles, and may cause operators to look at the "well-to-wheels" Impact of different fuels.

The battleground of truck efficiency in the next few years is likely to be weight. Despite incremental advances In every Iaspect of truck technology, the basic layout of the steel ladderframe chassis remains the same, and the kerb weight of a truck has changed little—extra sound insulation, emissions controls, larger cabs and added electrical systems all detract from the payload.

Trailer manufacturers have experimented with composite chassis, and monocoque bodywork makes an occasional appearance—but it has done so for at least 50 years. We are still waiting for a dramatic change in the structure of truck chassis.

AND THEN THERE WERE...?

:Y. Whatever trucks look like in 20 years' time, one thing that is likely to have changed dramatically is the badge on the front. The industry is going through a convulsive period of "rationalisation", with Volvo buying Scania (subject to EU approval) and rumours suggesting that other manufacturers are about to be snapped up. Will VW buy MAN? Will MAN buy Western Star? At least it's unlikely that Western Star will buy VW..

The Volvo/Scania deal is particularly interesting, as both firms have espoused modular design concepts, with one basic cab being adapted to nearly every model in the range. When the next generations of Volvo and Scania trucks emerge they will probably share a common platform—and the cab (the most identifiable part of a-truck) will be the same. It will take ingenious marketing and design work to convince buyers that there is a worthwhile difference between the Swedish brands, but it can be done: after all, Steyrt middleweight cab design has (with a fair bit of modification) served MAN and ERF well for years now, and Daf's 85CF cab can be seen on a Foden.

Whatever happens, it seems unlikely that there will be more than five major international truck builders in 20 years' time.