Robot bands playing jazz standards and a dazzling display of strange and intelligent vehicles met Judith Crosbie at Japan's Aichi Expo 2005

The theme for Japan's Aichi Expo 2005 must have bamboozled the various countries and companies when they sat down to come up with their exhibition ideas. "Nature's Wisdom" is not exactly what would come to mind for many when thinking back on the various world expositions there have been to date.

In particular, no other country has become such a byword for fast-paced industrial development as Japan. So how would a world expo with such a theme work - and in Japan of all places?

The task may strike some as near impossible for a big Japanese corporation like Toyota. Three years in the making, its exhibition organisers must have been keen to put on a good show given that its corporate headquarters are in Aichi province.

The Toyota pavilion might be wowing the crowds a bit too much, however, as the estimated queuing time for the exhibition is sometimes three hours.

Visitors are entertained by a show which kicks off with a robot brass band. Not only do they walk and move in time to the music, but these robots also play the musical notes, blowing into saxophones and trombones with artificial lungs and lips - all to the tune of When the Saints Go Marching In.

Then a different part to the show begins with a group of (human) dancers depicted as wretched beings writhing around a scorched earth with flames leaping into the air. These tormented beings are only taken out of their misery by the introduction of the car. But this is no ordinary gas-guzzling vehicle, this is the "i-unit".

The i-unit is Toyota's vision for the future - a personal driving machine, not much taller than a person, which is light and compact. The vehicle approaches the driver when called; it recognises them and lights up with a welcome.

It is designed in an upright position, allowing eye-level contact with those walking around but can also collapse into a lower high-speed mode. As it can communicate with other i-units, there are no crashes.

Though not whizzing around the pavilion like the i-unit, other Toyota ideas for the future show-cased include: the "i-foot", an egg-like structure on legs that carries people around streets; the "f-unit", for road transport of more than one person; the sports car "s-unit"; and even an "i-taxi" and "i-truck".

Transporting visitors around the expo, Toyota manufactured the Fuel Cell Hybrid Vehicle or FCHV-Bus which generates power using a hydrogen and oxygen chemical reaction with water as the only by-product. There is also the Intelligent Multimode Transit System which is a system of "intelligent" buses that can gauge time and distance between themselves and the next bus, thereby cutting down on accidents and increasing punctuality.

There is no shiny, artistic style to the outside structure of the Japanese pavilion: it looks for all the world like one huge half of a peanut. But the bamboo making up the structure will be able to regulate the heat, especially in the summer when Aichi is expected to reach over 35 degrees.

Then comes the part where expo theme meets expo expectation. Visitors enter a spherical room and stand on a partially glass floor suspended in the middle. All around there are clouds, and slowly the scene begins to drop to where birds are flying and skyscrapers reach. In a few seconds, we are plunged into a sea and as the oxygen bubbles above us fish swim around.

The scene is made entirely realistic by the visuals, sound effects and all-encompassing shape of the room. We then emerge from the sea and travel into space, getting a look at our tired, worn and polluted planet from afar.

Other national pavilions lost their way in the new expo vision about sustainable development. Many such as India and China are little more than tourist promotions with a few buzzwords about "getting power from the soil and the earth".

Canada is basically a beautifully filmed documentary depicting scenes from that country's beautiful natural environment.

Ireland's exhibition is small and short on the technological flaunting but it makes visitors think. Five replica high crosses - ranging in height from four to seven metres - based on crosses dating from the 8th and 12th centuries dominate the exhibition. Visitors can walk around the outside of the crosses and learn about Ireland from the perspective of its ancient landscape, its music and its people. There is a replica of the Book of Kells, a Kells crozier, an Ardagh brooch, a harp and uilleann pipes among other artefacts for visitors.

Perhaps the nicest thing about the Irish entry is that, after all the running about from exhibition to exhibition, you can relax - there are specially designed seats that are tilted so that when the visitor sits back, they focus on a screen above which shows scenes from Ireland.