I saw one of those stores promote their new products and I always wondering what are those number stand for?
Such as: "±3 / 11g" Accelerometer or "±400° / s" Gyroscope..... What are those ± numbers and g or s means?
G is a measure of
G is a measure of acceleration, 1G = 9.8meters per second squared (I believe, whatever the acceleration of gravity is, I think it’s 9.8). the +/- x degrees/s is a measurement of how fast the gyro/accelerometer can be rotated (and still measure accurately). It is degrees per second, so +/- 400 deg/s means that it can be rotated 400 degrees in a second and still get accurate measurement. The +/- (or plus sign over minus sign, too lazy to figure out how to type it) means that it can be rotated in either direction. With a gyro if you’re holding it in front of you it means you can rotate it clockwise, and counterclockwise, at less than 400 degress per second and expect accurate readings. With the accelerometer you can move it up and down (or side to side), at less than 107.8 meters/second^2 and expect accurate readings. Does that help?
More reading for what a "G"
More reading for what a “G” is @ Wikipedia
http://en.wikipedia.org/wiki/G-force
Confirms my memory of 1G “9.80665 metres per second squared”