iPhone 4 "gyroscope"

#1 accelerometer only measures "the down direction" by earth graviation, while the gyro measures your actual angular momentum.

together they give you 6 degrees of freedom if you implemented all of them in your OS4+ game on iPhone 4+

#2 Cue clones of all those Nintendo wii motion plus games :)

#3 yeah likely ... but hey, thats just the revenge after we had to endure the iphone stuff on dsi / wii store :P

#4 I don't get it. I thought the accelerometer measured if I tilt it (device) left, right, up, down, or rotate. But ok, if that is the case, what is the main difference? Accuracy? And is it still a joystick command in Torque?

#5 Gyroscope PROPERLY measures ORIENTATION. Accelerometers merely measure their accelerations, you can compare that to gravity to get a tilt (of sorts).

Big difference is rotating a gyroscope AROUND the axis that gravity is aligned with at any given time

#6 so is the accelerometer gone? is this relevant? Maybe I need to wiki gyroscope.

:)(()

#7 Both present

#8 I can't wait to see what we'll actually be able to leverage on this new device. In addition to the new three-axis gyro, and the already present accelerometer, there is also the addition of the ambient light sensor. I wonder if we'll get API access to the events triggered by that component. I could see an app designed to determine proper lighting levels for a movie set, stage setting, showroom, or what have you.

When I first read "proximity sensor" under the Tech Specs section of the product page, I thought "Sweet! A built-in range finder!" Of course, I quickly realized that all this was is the functionality for turning off the screen when the device is raised to your ear during a call session.

Given this addition of the gyro, I wonder how effective the iPhone 4 would be as a makeshift mocap (motion capture) device.

#9 hmm, so this does really present some new options.
but still I would like to know,
"is it still a joystick command in Torque?"

#10 I can't see why this wouldn't be setup in the same fashion when the time comes.. Ultimately it is another analogue input.

#11 @Rennie - As Craig stated, both components are still present. The gyro will only give you an accurate orientation (along the 3 axes) with respect to the gravity normal. The accelerometer will give you the force associated with linear movement (swing your arm left/right/up/down) whereas the gyro will give you angular momentum (picture twirling a ball on the end of a string above your head).

#12 A good way of understanding an accelerometer is to sit in an office chair with the data visible to you on your device. Now spin.

See how the acceleration is constant? However a gyroscope could tell you were spinning.

#13 oh ok, so the gyro creates a virtual sphere.

#14 not really, it just realises it rotates.

The accelerometer only realizes if you rotate it in relation to the "down to center of earth" direction.
Thats why turning on a chair won't have any impact, down will always be down.

(thats also why its an awfull situation for you if it is held in parallel to a table / put it on it and you unhappily used the z axis to measure the angle of a steering wheel for example. it will actually not rotate for an accelerometer)

#15 hmm, i am slightly confused as to what it does. i was, previously imagining a sphere where, in theory I was thinking, create a window. Imagine if the iDevice was the window, to the outstide world, where I would look thru the device to see the world. I thought the world would stay fixed (in one example) and as I moved it up, down, left, right, what I would see on the screen would change appropriately.


I think there is an example that Steve Jobs performed, I will look that up.

#16 a good video
www.youtube.com/watch?v=ORcu-c-qnjg

#17 So it is actually the reverse of what I was thinking. Instead of looking out thru the device, you look in (to the center of the sphere) thru the device. Berry interesting.

#18 An accelerometer knows how fast you went in some direction. A gyroscope sort of knows where you are, too (and has more sensitivity to the pull of gravity). The Hubble telescope uses gyroscopes since a compass is pointless out there :)

#19 I hope GG don't jump on this one and spend too many resources and trying to outdo wii. I think they need to concentrate on improving performance for the basic things first ;).

#20 I have not made anything with the accelerometer yet, but do have future plans. I am wondering, how do people find the sensitivity?