Track Boxes have integrated motion sensors which allow them to determine whether they are currently moving, or stationary, which has an impact on the way they manage trackpings sent by nearby transponders.

Stationary Algorithm

When a Track Box considers itself stationary, it tries to calculate and send the most accurate time possible, much in the same way as our traditional timing systems.

For Active Trackpings there are 2 values to consider:

• Maximum Observation Time (30s): The maximum length of time a transponder is monitored for before sending a passing. This minimises delays in receiving passings if a transponder is in range of a track box for long period of time.
• Reaction Time (10s): How long the device will wait for a TrackPing with a higher RSSI value before sending the data, except if the Maximum Observation Time is reached. This behaves in a similar manner to the Reaction Time of a Decoder. 

If a Trackping with a higher RSSi is received within 10s of the previous strongest signal then the transponder will continue to be monitored, unless 30s has elapsed from the first TrackPing received from the transponder. After a passing is stored then the Maximum Observation Time will reset.

In this mode, you may expect the detection to be accurate to approx 1 second, if the participants are traveling fast enough. If the participants are traveling slow and staying in range of the Track Box for a long time, you are likely to receive several passings. 

Moving Algorithm

A Track Box will switch to the moving algorithm as soon as it detects that it has been traveling at over 5 km/h.

When the Track Box considers it is moving, it does not make sense anymore to follow the transponders for a certain time to try and determine the highest signal strength, since both the Track Box and transponders are moving.

The Track Box then groups all the trackpings received and sends them every 10 s.

If the Track Box stops moving for over 1 minute, it will switch back to the stationary algorithm.

For every trackping, the Track Box indicates which algorithm was used. More information about this is available in the TrackBox Protocol.

For timing purposes, you obviously need your Track Boxes to be stationary at the timing location. Placing Track Boxes on an object that is moving slightly (e.g. on a tree, or on a floating boat or buoy) should not be a problem, as Track Boxes are able to ignore small movements.