A validation study was performed in 2016 and presented at the University of Nebraska-Omaha Biomechanics Symposium. The conference poster is attached and the citation is:
Palmowski JC, Pfeifer CM, Frederick TP (2016). Motion Timing Gates using Break-Beam Technology and App User-Interface. University of Nebraska-Omaha Biomechanics Symposium, Oct 13, Omaha, NE.
In summary, Dashr timing gates communicate via Bluetooth to your phone or tablet. Every phone/tablet is different, even the same model of phone/tablet - due to minor nuances in the hardware/electronics to what apps are installed/open. In order to account for this, we have developed a complex algorithm that takes numerous variables into account in order account for clock drift on both the lasers and the phone/tablet.
In this study a high speed camera (250 Hz) was used to test the dash and the 5-10-5. Results showed that the Dashr system measurements differed from the high speed camera measurements by 0.001 +/- 0.001 sec. This means that the Dashr system is accurate to within 0.000-0.002 sec (on average) though time rounded and presented at the hundredths place (0.01 sec) - per industry standard.
Given that the algorithm takes into account phone/tablet specific variables along with the lasers themselves to account for clock drift, connecting the lasers to multiple phones/tablets may result in slight differences in measurements as only one of the phones/tablets is used in the algorithm - the other is not accounted for.