Centaur stage

Volvo Construction Equipment's designers have turned their creative attentions towards imaging the articulated hauler of the future. The result is Centaur, a radical take on emergent technologies. Brian O'Sullivan kicks its imaginary tyres.

Some 'concept' vehicles are just plain silly. Walk around any motor show these days and you will see endless 'vehicles of the future' - complete with outlandish shapes, gull wing doors, sparkly exotic paint jobs, bubble cockpits and white leather. The chances of them actually becoming 'the vehicle of the future'? Zero. Zip, No chance.

But not all concepts are such childish distractions. Some actually signpost a credible future reality. Volvo Construction Equipment (Volvo CE) is one such manufacturer that takes concept vehicles extremely seriously. The launch in 2004 of its SFinX excavator caused a flurry of excitement in the press for its hybrid engine, quad tracks and lightweight lattice boom and stick. Then last year it unveiled Gryphin, the wheel loader of the future - sporting independent adjustable height suspension, electric drive, centre boom, moveable counterweight and commanding all round vision. Now comes the turn of the humble articulated hauler, the workhorse of so many large construction sites.

Like its mythical half man, half horse namesake, the Centaur hauler is swift, flexible, strong and intelligent. And while recognisably a Volvo, Centaur radically redraws the traditional hauler profile. With its ultra-compact front unit, arched back and super-sized wheels, there is no doubt that this is a strong, fast moving animal.

The project has been directed by Volvo CE's head of research and technology, Lorenzo Terreno, with the additional guiding hand of master designer Hans Philip Zachau of Lighthaus Industrial Design. But what makes Volvo's approach to concept vehicles so different to its competitors, is that engineering and production are also involved in the process - and critical to the outcome.

"We want everyone involved in this 'blue sky thinking'," says the charismatic Italian Terreno. "Of course we want to make a dramatic design statement of our innovative thinking, but we also want our creations to be rooted in engineering reality, and to be feasibly produced, if not today, then in the foreseeable tomorrow. What they must not be is the pointless imaginings of a sketch artist."

Radical reality

A good example of this 'realistically radical' approach is that the Centaur has wheels and not tracks. To make the machine look dramatic tracks would have been more visually surprising, different and 'futuristic'. But Centaur is intended to be a fast moving load carrier - and the fact is that wheels are better at this than tracks - and still will be in the year 2020 and beyond. So tracks are Out and wheels are In. For the same reason futuristic joysticks were considered but discarded, as it was thought that when moving at speed over rough ground operators find the traditional steering wheel easier to grab onto, more intuitive and confidence inspiring.

Centaur has an uncompromising focus on safety. Haulers move heavy loads at fast speeds over rough ground - so stability, visibility and traction are the project's guiding principles. Protected by an all-round lazer proximity scanner (okay, so there is some James Bond in here), the machine is always aware of people and objects in its immediate vicinity. This device is coupled with a proactive protection system that both tries to avert collision and comprehensively absorbs the forces of impact should one occur.

Nose job

The operator of the future will no longer have to clamber up ladders into the cab - the cab will 'kneel down' to ground level, allowing the operator to walk up a short flight of steps into his well-lit workplace - through the front door. In fact the whole 'tractor' unit is much more compact.

Today's haulers are roughly split 50/50 - half tractor unit and half haul body. Having a compact tractor unit not only reduces the amount of heavy metal moved, saving energy, but also makes the hauler shorter and therefore more maneuverable. The loss of the long 'nose' also aids front visibility. In fact the new design of the front unit combined with intelligent all-round glazing in the cab to give the operator commanding views - and a Heads-Up Display keeps his eye on the road ahead. Unfortunately there are no smoke screens or ejector seats. (Sorry James).

The operator's fingerprint becomes his 'key' and using this biometric data Centaur automatically adjusts all controls to suit that operator's preset preferences. The ride will be super smooth as the cab floats, levitating in mid-air using an electro-magnetic field like the Japanese Maglev bullet trains.

Sitting on a slightly arched chassis with its super sized wheel and low profile tyres, the Centaur is a proud looking beast. But despite the loudness of its appearance it moves almost silently thanks to its ultra efficient electric hybrid drive system, which is further helped by regenerative braking systems and solar panels to power auxiliary controls. Hydraulics are minimized on the Centaur, but where they do exist, they are filled with environmentally safe water rather than oil. Water is clean, cheap and plentiful, leakages would not be such a problem, there would be no nasty oil spills and maintenance and service costs would plummet.

Centaur uses its electrical generator to power independent motors inside each wheel. This liberates the wheels to move completely freely over rough surfaces. The suspension is also radically different. Each wheel hangs on a swing arm that works similarly to those found on modern motorbikes. Inside these lightweight and torsion resistant units can be found dampers. The swing arms allow far greater maneuverability of each wheel.

This new suspension system also allows the machine's ride height to be adjusted - raising it to offer greater clearance over rough ground and lowering it for easier loading and fast, safe hauling over smoother surfaces. And the Centaur is fast - despite the great weight upon its back - up to 70 km (45 miles) per hour is quite possible; drastically reducing haul cycle times. The adjustable ride height would also be useful in mining applications, removing much of the need for specialized mine hauler variants. The clever suspension system also has the knock on effect of reducing the stress on the articulating joint.

Delicate balancing act

Without doubt the most striking feature of the Centaur is its ability for the front 'unit' to uncouple from the 'trailer'. It balances using powerful computers and gyroscopes, and this ability to disconnect the trailer opens up the possibility to rapidly change the work application. This is not quite the science fiction it may seem at first. The Segway Personal Transporter uses this approach with great success.

The benefits of being able to disengage the tractor from the trailer are manifold. Using specialized trailers, Centaur can be a hauler one moment, converting to a pipe or log carrier - and then a liquid container the next. This would be a boon to the hauler rental sector. Another benefit of this feature is that as each wheel has its own electrically powered motor(rather than driven via a mechanical drive train from the tractor), the trailer can be operated remotely, only reconnecting to the tractor unit to recharge the onboard batteries. This solution would be useful in hazardous situations or where one operator can remotely control several trailers safely; considerably improving production efficiency. Having a two-part machine would also help with transport and shipping.

Safety and efficiency combine beautifully in the way the body empties its load. Centaur overcomes this with an ingenuous two-piece haul body. When tipping, the rear/highest section of the body slides down into the front section, compressing the load material out in a controlled manner. So the weight of the load stays low - greatly improving stability.

The Centaur design project is not just science fiction. The result of collaboration between Volvo's designers, engineers and production teams, Centaur is a serious attempt at predicting the evolution of the articulated hauler. Volvo is in a good position to make this prediction - it has been the leader in articulated haulers since it created the market in 1966. In the intervening years more than 50,000 machines have rolled off the production line; earning articulated haulers a legendary reputation for strength and unstoppable progress. Centaur - or a hauler very much like it - is simply the next generation.