At CloudTimer we are doing a lot of lab and field tests to test & prove the accuracy of our sports timing app. While doing so we felt the need to clarify what this means: accuracy. Because a system can be extremely accurate, but that doesn’t necessarily mean that the timing of an athlete will be accurate. In this article we aim to give a high level explanation of the several factors involved in this topic.
In accuracy there are two things to separate: timing accuracy and system accuracy. The two will be further explained below.
What is timing accuracy?
Timing accuracy tells us something about the quality of the final results. It is a combination of the technical system, the operator of the system and the sport that is timed. A lot of effort always goes into the perfect system, to measure at a very high resolution or sample rate, but what happens in the field can have a great impact on the result.
System accuracy describes the quality of the clock in the timing system. When working with only one clock, the sample rate, and clock drift play an important role (i.e. when the clock indicates a minute has past, is this really a minute or maybe slightly more or less than a minute). When working with multiple clocks in a timing system, then not only sample rate and clock drift but also the synchronisation between the clocks play a role.
As was already above mentioned, timing accuracy is a combination of the technical system (with a system accuracy), the operator of the system and the sport that is timed. The operator can have a big influence on the timing accuracy when push button timing is concerned for instance. In this case the observational capacity [A] (when does the athlete cross the start/finish line), reaction speed [B] (how quick is the button pushed after an observation is made) and the reproducibility (will [A] and [B] be the same for all 100 athletes) of the timing operator have a very big influence on the timing accuracy. Finally also the sport in question has a influence on the timing accuracy. In cycling the front wheel is a very distinct marker to cross the start/finish beam (which will always be the same). In contrary in Canoe Slalom it is sometimes unclear if the bow of the canoe, the paddle, arm, body or water drop triggered a start/finish beam.
The question is, whether a very accurate system is needed to have a good race result. As CloudTimer (in stopwatch mode) is a manual timing system, the timing accuracy can be considered to be at 0.1 to 0.05 of a second. This accuracy mainly depends on the operator, not the CloudTimer system. The system should be at least capable of timing well within this timing accuracy. It must therefore be at least twice as accurate as the timing accuracy, which is between 0.05 and 0.025 seconds. Already in a previous article we showed preliminary results of our lab timing tests. In a next article we will show more results on to what extend CloudTimer is able to time in this range!