PS3, Wii controllers go hi-tech
2006-11-21 13:35
New York - With a tilt of your wrists, the dragon you're riding dives toward the water below. With another movement of your hands, as if pulling back on imaginary reins, the scaly beast pulls out of the dive into level flight, flapping its wings.
That's how the unreleased game Lair will work on the Sony PlayStation 3. Like Nintendo's Wii console, which went on sale two days later, it uses a motion-sensitive controller in an effort to make games more intuitive to play.
The controllers make a higher level of realism possible, too: In the sports game bundled with the Wii in the US, the stick-shaped controller doubles as the handle of a virtual tennis racket or golf club.
The technology behind motion-sensing has been around for a while, but recent technical advances have radically brought down the price - and the size.
The new game controllers are the first gadgets that promise to bring the technology into the hands of millions of people, and manufacturers are now using motion sensors in other consumer products, including cellphones.
The technology is a wonder of miniaturisation and precision. Here's how Benedetto Vigna, head of the unit at Switzerland-based STMicroelectronics NV, which makes a motion-sensing chip for Nintendo, explains how it works:
'Movements are minute'
When you wave around the new Nintendo controller, two tiny, flat pieces of silicon inside it, each weighing about a millionth of a gram, flex against silicon springs that hold them in place.
The movements are minute, or to put it another way, they're on the scale of 10 to 100 hydrogen atoms stacked side by side.
But these tiny movements can be measured with incredible accuracy. A charge is applied between the moving pieces of silicon and two nearby sensors.
Faint fluctuations in that charge, as small as that of 10 electrons, are picked up by a chip that translates it into an understanding of how the controller is moving.
The two moving weights, which fit together on an area less than a millimetre square, have different roles. One has two sets of springs, which allow it to move from side to side and back and forth.
The other weight is a flat piece anchored almost like trampoline. It senses vertical movement. This way, the chip can distinguish motion in all three dimensions of space.
Analog Devices Inc of Norwood, Mass makes a similar chip, which goes into the main Wii controller, the stick-like Wii Remote.
According to Analog Devices, ST's chip is used in the auxiliary Freestyle controller (popularly known as the "Nunchuck") that connects to the larger controller for some games. ST said it was not allowed to say where exactly its chip is used.
Remote 'knows' where it is
Sony Corp's "Sixaxis" controller for the PS3 also has an accelerometer. The six axises the name refers to are the three dimensions of space, plus three axises of spin. The company hasn't revealed who makes the chip.
The Nintendo Wii Remote one-ups the Sony controller by including an infrared camera. It picks up signals from a sensor bar the owner attaches to the television set.
This enables the remote to "know" where it is in relation to the screen, so the player can use the controller to point to things on the screen - a useful feature in shooting games (and a lot of games are shooting games).
So where has this technology been until now?
Accelerometers have been used to guide missiles and aircraft, said Richard Marks, who worked on an underwater robot before his job as head of special projects at Sony Computer Entertainment America.
"We had a $25 000 inertial system that was probably comparable," to the one in the Sony controller, he said. "These things have become so much less expensive."
In the past, accelerometers were large mechanical devices, with springs or liquids that sensed orientation and movement. The reason they can go into game devices now is that they're made not by assembling mechanical components, but with the same techniques used to make computer chips.
Vigna described a method of successively adding and etching away layers of silicon on large platters with hundreds of individual chips to build up the mechanical part of the accelerometer.
The platters are then broken up into individual chips. That means the chips can be made consistently and cheaply with precision down to the micron - one millionth of a metre, or about one hundredth of the width of a human hair.
Other so-called microelectromechanical systems, or MEMS, that are made in similar ways include chips in video projectors (where they flip thousands of tiny mirrors to build up the image) and in inkjet heads. MEMS technology is seen as a fertile field and is related to another hyped area, nanotechnology (which deals with even smaller scales).
The auto industry started using silicon accelerometers in the late 1980s for the sensors that activate air bags, Vigna said, and each successive generation since then has become smaller and cheaper.
"What ST is doing now is bringing this from the automotive industry to the consumer," Vigna said.
Accelerometers have made their appearance in game equipment before. In the late 1990s, Microsoft put out a game controller with a limited "tilt" function, but it never did well. In 2001, Nintendo released a Game Boy Colour cartridge that sensed motion, but it worked only for the included game.
But with the Sony and Nintendo controller, accelerometers look set for a breakout in consumer devices.
- AP