11 July 2023

Enligthening : How chronometry and measurement work

For this latest episode of lighting, let’s delve a little deeper into the technical side of things. For each competition, we need timing and distance measurement, otherwise we won’t have any results. Let’s find out how it works.

For these Para Athletics World Championships – PARIS’23, ATOS is managing all the race timing and measurements for the jumping and throwing events. Let’s start with timekeeping. It may seem complicated in practice, but it’s easy enough to understand.

The main element is the photo-finish camera. This is located at the level of the finish line and determines the “zero point” of the time. The timer starts when the gun is fired and stops as soon as the camera detects an athlete’s first bust.

For the 100m, 200m and 400m events, the software that records the times is programmed to recognise the lanes and therefore the athlete. However, beyond this distance, electronic chips are fitted to race numbers. When they cross the finish line, they are detected and the stopwatch is stopped.

And to measure jumps and throws?

For the long jump, two cameras are positioned in the stands. One frames the call board and creates a point “A” at the boundary of the red plate. The second frames the sandbox and creates a point “B” at the beginning of the first track left in the sand. A computer then calculates the distance between point A and point B to determine the distance. Measurement takes just five seconds.
For the visually impaired long jump, on the other hand, measurements are taken “the old-fashioned way”, using a measuring tape to measure the distance between the footprint on the lime and the first mark left in the sand.

A theodolite is used for throwing events. It is a measuring instrument used by surveyors to calculate angles to determine distance. Before the competition, the machines were calibrated on the line not to be bitten to validate their throw, in order to create a 0 point. After each throw, an official plants the theodolite in the mark left on the ground and in a few seconds the distance of the throw is measured.

It should be noted that these measurements are monitored by officials in order to validate them. In the event of any doubts or technical problems, the officials will always repeat the measurements with a metre.