Re: Accelerometer Control method games.. web browsing etc.
 

the camera could do that...

Re: Accelerometer Control method games.. web browsing etc.
 

Ah okay, that did cross my mind but didn't know how accurate it would be.

In that case... roll on :)

Re: Accelerometer Control method games.. web browsing etc.
 

I'm sorry if my comment is a bit dumb but, isn't the job of an accelerometer to detect movements? Thus detecting if you are turning your head?

Re: Accelerometer Control method games.. web browsing etc.
 

I think it's largely intended to detect the orientation of the device, and movement detection comes as a side benefit.

I've done a little reading up, but have no programming experience with the accelerometer , so I'd welcome correction ...

As I understand it, you can read out from the accelerometer at any time three values each of which tell you which way gravity is pulling at that time, relative to one of the three axes of our 3D universe - basically the roll, yaw, and pitch of the device.

However, when you accelerate, or start to move, the apparent force due to gravity changes - like how you get pulled back in your seat when a car accellerates quickly.

So working backwards you can use the "gravity" information to try and work out movement (integrate once) and position (integrate again) - this is known as dead-reckoning.

This is normally done with a gyroscope as well as an accelerometer, and is sometimes known as inertial navigation.

I do wonder though, whether the accelerometer can give you enough information to distinguish between an acceleration or movement and a change in orientation?

Tilting the device back should induce the same type of readings from the accelerometer as moving it suddenly forward while keeping the orientation the same, but if the reading is given as a vector, then the magnitude of the vector might be greater in the movement case, which would enable you to distinguish between an acceleration and a change in orientation.

Re: Accelerometer Control method games.. web browsing etc.
 

I was actually thinking of adding a tab and bar input utility this way. I have no experience using a device with an accelerometer, but it seems like there is huge potential for augmented input by tracking motion, screen touches, and the keyboard all together. There's also the proximity sensor.

I am excited to get a gadget with accelerometers so i can see if such a plan is even possible.

Re: Accelerometer Control method games.. web browsing etc.
 

An accelerometer measures acceleration. By integrating the acceleration one gets velocity and by integrating the velocity one gets postion relative to the starting position. If you have three axes of acceleration you can calculate the position and orientation of the device relative to the start point.

Re: Accelerometer Control method games.. web browsing etc.
 

I don't know anything about physics and stuff but, from what I see in other phones with accelerometer (one guy made an app where you could see 3D objects from different prespectives, as if it were a camera, by moving the phone), it should be possible to detect every movement of the phone. But, as I've said, since I don't know the technology, I might be very wrong...

I believe it depends on the number of "accelerometers" it has... Doesn't the N900 has 6 points from wich you can read?

Re: Accelerometer Control method games.. web browsing etc.
 

Accelerometers can detect which direction is down and also detect linear motion. To detect rotation you need gyroscopes. You could still detect rotation of your head, though, since the N900 wouldn't be centered on the axis of rotation, and hence would be accelerating linearly as well as rotating.

If anyone can point me to what accelerometer the N900 uses I'll do some calculations to see whether it's feasible to detect the side-to-side head motion.

I'll post a second message in a little while with more info about orientation/movement detection with accelerometers. (Wife wants to start our movie now. :))

Re: Accelerometer Control method games.. web browsing etc.
 

I was writing about this sort of possibilities in the Brainstorm: Make the browser feel more a part of the system. Please go and add/vote for your ideas there. Who knows, maybe Nokia or somebody from the community will implement them :rolleyes:

Re: Accelerometer Control method games.. web browsing etc.
 

The N900's accelerometer seems to be the LIS302DL both from searching on this site and the dmesg and lsmod output at http://www.smartnews.hu/2009/10/rend...k-az-n900-rol/

I think the possibilities for interface using accelerometer are very interesting. One idea I had was that the device could be it's own mouse - the cursor would remain physically in one place but move on the screen as you move the device.. :-) I've no idea whether this is possible with the N900 hardware but it would be fun to try!