Accelerometers and PDAs

Tilt Sensors

If you think that the accelerometers that comes with the latest PDAs are cool and high tech, think again. Accelerometers and tilt-sensors has been around for a while (think Nintendoo Wii). However, accelerometers are finding themselves in many consumer electronic products nowadays.

An accelerometer measures acceleration and gravity induced reaction forces, while a tilt sensor usually deploys an encapsulated fluid to measure, well, tilt.

The earlier orientation sensing technology was first used in aircrafts. Gryoscopes was installed to allow pilots to know their orientation (so that they are not flying upside down) in zero visibility conditions.

Patented by Gyration, miniature gyroscopes was then introduced into the humble computer mouse. This allows the mouse to be used in mid air (usually wireless) and interact with the PC. And these, for obvious reasons, are called gyromouses.

According to an internet article, Samsung may be the first to introduce accelerometers into mobile phones back in 2005. But the technology used is slightly different from gyroscopes. The accelerometer was used, which provides tri-axis (X, Y and Z axis) sensing. This technology was also announced by Nintendo in the same year as they released the Wii Remote (or 'Wiimote'), and thus introduced orientation sensing into the world of gaming.

Either the accelerometer or tilt sensor are commonly used nowadays in laptops and tablets such as the Fujitsu T4020 Table PC as a shock sensor to protect the harddisk. And not to forget the latest cameras (Canon Powershot SD750) to provide automated screen orientation rotation. (Perhaps I should install a tilt sensor to my coffee cup to minimize spilling... )

Here is a video of a simple game on an accelerometer enabled PDA.


HTC Diamond's Teeter Game


Due to the accelerometer's ability to detech and emulate physical motion, this technology may be useful in encouraging students to explore physics related topics through interaction and games. Here's an article from Physorg.com showing how the Nintendo Wii was rigged to teach stuents mechanics.