G-Sensor vs. Accelerometer... difference?

[WhiteBlazer01]

So, just out of curiosity, I read that we (TP2) have a G-Sensor, and iPhone has an Accelerometer. What is the difference, if any?

[ihavenoclue]

They're the same thing to my knowledge

[WhiteBlazer01]

That's what I was thinking too, but I wonder why they are called different names. Is G-Sensor patented by HTC? maybe just a branding thing? I'm just wondering. I know they essentially do the same thing. Also, I hear Wii controllers being referenced to having accelerometers. I never heard a Wii controller having a G-Sensor, so maybe there's something to it? I don't know...

[MordyT]

Wirelessly posted (HTC Touch Pro2: Opera/9.5(Microsoft Windows; PPC; Opera Mobi/16643; U; en) HTC_Touch_Pro2)

If I am not mistaking, the accelerometor can track motion and therby track orentation by seeing changes of motion while a Gsensor can tell oriantation as well as track motion from changes in orentations.

[sriiyyer]

G-sensor is a gyroscope, in other words an orientation sensor.
motion sensor is more accurate, it MAY or MAY not have G-sensor's capability, this depends on the software implementation. but the hardware itself is capable of detecting and reacting to all kinds of movement.

G-sensor needs _relatively_ sudden movements to activate the gyroscope (think of a marble in box), if the phones (the box) is in landscape, and you tilt it to portrait, the gryo detects it (ie marble rolls to one side). However, if you keep the phone/box's orientation the same, and move the phone closer or further from you (assumign you ar eholding the phone): now if you move it slowly, the marbles won't roll, this is g-sensor. becaue it can't detect this movement. but if you suddenly jerk the phone/box, even if the orientation is the same, the g-sensor should detect it (ie the marble will move). ummm.. just like those dice games on iphone/itouch (if you 've seen the latest itouch commercial).

motion sensor detects all kinds of movements, it's only up to the software to decide if all functionalities are implented or only "up till" the G-sensor capabilities are implemented or something else. best example, G1's compass view, slow movement with the phone in the same orientation will pan around the map.

that being said even the motion sensor has its limits, if you move the phone uber slowly, i bet it won't detect the motion, unless it's military grade (read: 007 gadget )

[Miami_Son]

Accelerometer and G-sensor are NOT the same as it applies to phones. The LG Incite (my last phone) has an accelerometer, but could not use programs or games designed for a G-sensor. The TP2, Tilt 2 has a true G-sensor. An accelerometer can only detect whether the phone is in portrait or landscape mode, basically it reads the phone orientation in 1 plane (horizontal or vertical), whereas a G-sensor reads orientation in 3D. It can tell if the phone is horizontal or vertical and by how many degrees each way and side to side.

Both terms are actually misused in this application. An accelerometer or G-sensor is a device used for measuring movement, particularly velocity and deceleration, not orientation.

[roz1]

Actually, I believe that accelerometer and G-sensor refer to the same thing.

G-sensor is a marketing-type name for accelerometers. An accelerometer can measure linear acceleration such as the force of gravity pulling it down (that's how it knows your orientation). This where they get the "G" from, or similarly G forces that a fighter pilot would feel. As Miami Son mentioned above, not all accelerometers are created equal, but most new phones have pretty decent accelerometers since they are now relatively cheap.

Gyroscopes measure the rate of rotation (i.e. twisting motions).

The TP2 has an accelerometer.
The iphone has an accelerometer. If I'm not mistaken, the iphone 4 also adds a gyroscope.

[bastian74]

The TP2 "g-sensor" is a 3-axis accelerometer. That is all.

[Miami_Son]

I think this is a case of manufacturers adopting a word, mistakenly, as a marketing tool. In my line of work we use accelerometers as measuring devices. They tell us things like velocity, deceleration, force, etc...all things related to actual movement and not static orientation.
If you look at the calibration app for the "accelerometer" on the TP2/Tilt 2 you will see a bubble level. When has a bubble level ever been referred to as an accelerometer? It isn't. It doesn't measure movement. In fact, it specifically is designed to be used on a non-moving surface to get an accurate reading. Calling it an accelerometer is a misnomer.
Unfortunately, phone manufacturers probably thought it sounded better than saying the phone has a gyroscope in it. Most people associate a gyro with those circular toys we played with as kids and would probably scratch their heads at the idea that there was one inside a phone. Few people know what an accelerometer is, so it sounded much better as a marketing phrase. G-Sensor is just an elevation of the marketing art.
Those of us who tinker with things like R/C helicopters know that electronic gyros exist that can be put into a package smaller than your thumb. We would never consider calling them accelerometers, though.

[bastian74]

It is an accelerometer. Holding the phone still does have an acceleration applied to it, the pull of the earth. If you throw the phone up and let it free fall the accelerometer will read zero on all 3 axis.

Download shocktester. It will print out acceleration in all 3 axis but will not show any rotation. The bubble level works by detecting the amount of acceleration in the horizontal plane, relative to the phone. A gyroscope would make a terrible level.

And a bubble level is in and of itself an accelerometer. If you hold one level and accelerate horizontally you'll see the bubble move towards the direction of acceleration.