Accelerometer in Video Overlay-Lineal Acceleration Reversed?

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marchewitt
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Accelerometer in Video Overlay-Lineal Acceleration Reversed?

Post by marchewitt »

Hi, I just set up LapTimer v18.3.7 on my iPhone 5 (no external sensors). Great product! I'm still testing it out, but I created a practice video with data overlay, and I noticed that the lineal acceleration display seems to be reversed. When I brake, the dot goes down, and when I accelerate, the dot moves up. I noticed there was a toggle to "reverse lateral acceleration" in Expert Settings, but not lineal. Is the display configurable?

The lateral acceleration seems to be OK (e.g., when I turn right, the dot moves left). Also, when I have the phone in "Acceleration" view, the display seems OK (when I tip the phone forward simulating braking force, the red arrow and green areas move up/forward of the car). The only thing that appears to be affected is the accelerometer in the video overlay.

FYI, I had my iPhone mounted in landscape mode, with the screen facing me, toward the rear of the car.

I appreciate any help you can give. Danke!

-marc
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Harry
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Re: Accelerometer in Video Overlay-Lineal Acceleration Rever

Post by Harry »

The only reason I can think of is the device has been rotated after the stand still calibration has been finished. There is no reason LapTimer should display the same data in video overlays different than in the real time view. I'd suggest you rerun the process and make sure you keep this order:

Mount the device in landscape and switch to Video View. In case the green dot is not centered (wrong calibration), touch the circle and LapTimer will start calibration over. Now, record a short drive manually (i.e. using the red / green buttons in Video View) and make sure you get correct displays while driving. Back home, create an overlay and check if everything is fine.

- Harry
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marchewitt
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Re: Accelerometer in Video Overlay-Lineal Acceleration Rever

Post by marchewitt »

Thanks for the reply and sorry for the slow response.

I've recorded another couple of test videos and the issue hasn't repeated itself - in the subsequent test videos the accelerometer seems to act correctly.

Thanks again for the follow up, and I'm really enjoying the app.

-marc
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