Re-calibrating acceleration using the iPhone

Help on issues you run into with LapTimer; in case you have a question on how to use LapTimer, use the forum "Using LapTimer" instead
Post Reply
jgalaxy
Fewer than 10 Posts
Fewer than 10 Posts
Posts: 1
Joined: Sat Jul 28, 2012 11:39 pm

Re-calibrating acceleration using the iPhone

Post by jgalaxy »

I've never been able to calibrate my iPhone, so today I decided that I would stubbornly follow instructions to a letter and be patient. Previous attempts had me giving up after 5 minutes.

I got through the the first two (orientation and standing still), but on the third step when it asked me to drive a steady straight line at a moderate speed it would check it off and ask to accelerate and from there would immediately return to the 3 step asking me accelerate in a straight line.

Sometimes it would check itself off and ask me to accelerate again, but would immediately return to the third step, drive in a straight line.

I gave up after 30 minutes.

Does anyone have any tips for me? I'm sure it cant be this difficult to calibrate.

Thanks
User avatar
Harry
Site Admin
Site Admin
Posts: 10518
Joined: Sun Sep 12, 2010 10:32 am
Location: Siegum, Germany
Contact:

Re-calibrating acceleration using the iPhone

Post by Harry »

During this step LapTimer tries to understand the rotation of your iPhone around the upward axis. To accomplish this, it tries to detect a straight line driven, and requires a hard acceleration / deceleration them. The straight line is detected by checking orientation GPS delivers, and acceleration from the built in accelerator.

The problem with this step is needs to be restrictive in terms of direction variation, and acceleration. Otherwise, LT will calibrate a wrong rotation.

You will hardly ever achieve step #3 on public roads. It typically calibrates the first time you go down the start / finish line, braking ahead of its end.

Last remark: the most relevant calibration step is the second.

Harry
Image Image Image Image
Post Reply