Bikers speed on a virtual road

HOW CAN can one ride the world's most powerful motorcycle and roar along twisting open roads at breakneck speed in perfect safety? Virtual reality, of course.

A group of engineers from Pisa's Santa Anna engineering institute is designing a complex machine, a motorbike simulator, which will enable the rider to alter virtually every variable involved in the construction and dynamics of a two-wheel vehicle as he or she goes along, and to test these adjustments on a variety of roads and road surfaces.

The purpose is not, at least for the time being, entertainment. Rather, the new machine will be used for designing scooters, mopeds and motorbikes.

Project coordinator Massimo Bergamasco, said: "The tester who is riding our machine will be able to alter almost everything. We can simulate changes in centres of gravity, steering geometry, size of wheels, shape and type of tyres, engine power, gearing, acceleration, spring rates and shock absorbers. We can even create head winds and cross winds."

The Santa Anna institute is one of Pisa's three universities, atypical in that it has a population of only 100 students, 20 of them postgraduate researchers, and a staff of 14 full-time lecturer-researchers plus about 20 researchers on various types of contract.

While engineering is also taught at the other two universities, Santa Anna specialises in applied engineering and is in close contact with industrial firms.

The project for the "virtual motorbike" is largely financed by the European Union and has the collaboration of the University of Bochum, near Dusseldorf, which is working on the acoustic software.

The project is also supported by Piaggio, the Italian firm that produces the Vespa scooter and a variety of other two-wheeled vehicles. Piaggio has provided a building in its manufacturing complex near Pisa and is supplying much of the mechanical hardware and technical facilities.

"The machine is based on a Stewart platform, which is controlled with the same type of system of prismatic pistons used in flight simulators," said Mr Bergamasco.

"The rider has a seat, handlebars with controls and footrests, all adjustable, and he or she will have all the visual, physical and acoustic feedback involved in actually riding a machine in a certain set of conditions: wind, noise, acceleration in all directions.

"The key is computerised control which harmonises all the stimuli into a single experience. Acceleration will be simulated by tilting the whole platform. Backwards for acceleration, forward for deceleration," he said. "We will be able, for instance, to create a virtual machine of a specific type and then test it in different conditions, altering its characteristics.

"The simplest example is to find an ideal compromise of suspension rates which will make travel comfortable on bumpy roads, but will give acceptable stability on high-speed curves."

The virtual motorbike is not working yet but design is well advanced and Mr Bergamasco's team is already negotiating with outside suppliers for the many, and varied components which are required.

There seems nothing that the Santa Anna machine will not be able to simulate. But anyone who has ridden a BMW or a Moto Guzzi, in which the engine turns along a longitudinal axis, might wonder about the "torque effect" of the rotating masses inside the engine on the machine as a whole.

"We have not got that one solved yet," admits Mr Bergamasco. "But we are working on it."