Vecorder

Impress your friends by showing them how smart your smart phone can be! Use this app to estimate the height of objects by using the built-in acceleration sensors of your device. View the demonstration video to get an impression of the mechanics of this tool!

The Vecorder (Vertical Extent Recorder) is a tool to scan objects for their vertical height. Move the device along the object bottom-to-top (or vice versa) to perform a height scan. Note that the accuracy of the scan is dependent on the acceleration sensor accuracy of your device and the user input. Though the Vecorder contains techniques to compensate sensor errors it is vital to conform to some rules to obtain satisfying results:

1. Try to move your device smoothly but determined straight from the start to the end position with well-defined acceleration impulses.
2. Avoid acceleration spikes e.g. by dropping the device or hitting it on other objects. Even slight hits can reduce the accuracy significantly!
3. Only move vertically (along or contrary to the force of gravity).
4. Do not change orientation of the device while performing a scan.
5. Try to keep the recording phase as short as possible (typically several seconds) to reduce error-accumulation of the acceleration sensors.

By following these rules the typical relative error rate of scans range between 1cm and 5cm per 1 meter. If your device exhibits deviating error rates or if you have other comments or suggestions please write a feedback to vecorder@mathfactorysoftware.com with your device model included.

Vecorder Procedure Description

The recording procedure consists of several phases:

Phase 1 (Initial Position Averaging Phase): Steady your device at the initial record position and hold it until the start signal occurs.
Phase 2 (Recording Phase): Move your device vertically up or down to the record end position. See above for accuracy improvent tips in this phase.
Phase 3 (End Position Averaging Phase): Steady your device at the end position of the recording until the end signal occurs.
Phase 4 (Error Compensation Phase): Potential errors of the recording will be detected and the result will immediately be compensated.