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Down to the wire

As the cost of electronics reduces, more and more sports are taking advantage of electronic timing systems. One area where electronics has been in common use for several decades is competitive water sports. Dave Elsy, consulting technical author, provides some background to NBS work section, W73, which deals with automated timing and scoring systems.

International competitive aquatic events are governed by the Federation Internationale de Natation (FINA) (www.fina.org). In the UK, competitions are controlled by the Amateur Swimming Association (ASA) (www.britishswimming.org). Both organizations incorporate automated timing and scoring systems in their rules, for swimming, competitive diving and synchronised swimming, which must be followed in order to ensure that timings can be officially ratified by these organizations. Automated timing and scoring systems (known as ‘automated officiating equipment’ by the ASA) consist of a microprocessor-controlled timing controller which accepts inputs from the starting system, finishing touch pads and timekeepers’ manual push buttons. For diving and synchronised swimming, inputs to the controller are provided from hand held scoring devices used by the judges. The timing controller provides outputs to the automated scoreboard and to a results printer.

Timing controller

The timing controller is started automatically by the starting system, operated by the starter. The starting system is usually situated next to the starting line and produces a loud acoustic signal reinforced by additional speakers local to each swimmer’s starting platform. A visual signal can also be connected to aid any competitors with impaired hearing. Timing controllers are normally fitted with a rechargeable battery-powered uninterruptible power supply (UPS) system (for international events there are usually two UPS systems) so that any interruption to the mains power does not affect the timing operation.

Starting signals

Swimmers start from special starting blocks which can be fitted with devices to indicate when the swimmer leaves the block. The timing controller can be programmed to display a ‘disqualified’ indication on the scoreboard if the swimmer leaves the block before the start signal. A similar arrangement is used for relay races to indicate if a swimmer starts before the preceding swimmer has contacted the touch pad.

Finishing signals

As the swimmers reach the end of the course, they contact the touch pads, which each send a signal to the timing controller. When the final swimmer finishes the race, the placing and timings of the swimmers are automatically computed and displayed on the scoreboard. As a back-up in case of failure of a touch pad, facilities for lane timekeepers’ manual push buttons (up to three) are usually provided, depending on the importance of the competition.

Whilst electronic touch pads have been available in the United States since the late 1950s, their acceptance in other parts of the world was slow. Finishing signals were usually provided by hand-held push buttons operated by the lane timekeepers, several of which were required at each lane. Touch pads did not become widely used until after an incident at the 1960 Olympic Games, when a swimmer clearly won but was officially judged second.

They have since become increasingly common and are now used in all major competitive swimming events. Indeed, world records can now only be ratified by FINA when an automated timing system is used. Touch pads are sized to suit lane widths, between 1950 mm and 2400 mm. The standard swimming length for international competition is 50 m, with 25 m used for lower class events. To allow for the touch pads to be set up in the pool (sometimes at both ends) the pool must be oversized by at least 20 mm.

Removable equipment

As very few swimming pools are continuously equipped for competitive swimming events, the equipment involved (with the exception of the scoreboard) is not permanently fixed. Whilst the cabling is permanently installed, the timing equipment is usually only installed for the duration of competitive swimming meetings, and is removed when the pool is available for leisure use. To facilitate this removal, equipment fixings and cable disconnection facilities are provided at the start and finish and at the timing console location. Wiring is usually routed in corrosion resistant (PVC-U) conduit concealed within the pool construction, with deck terminal boxes to allow each timing component to be interconnected, usually via a plug and socket arrangement.

Starting blocks are usually fixed to threaded sockets cast into the pool deck and touch pads are fixed in a similar manner or hung from the pool gutter. The timing controller and results printer sit on the timekeepers’ table, which is positioned at the side of the pool so that the proceedings can be observed by the timing system operator. In pools which regularly host major competitions, purpose-built air-conditioned control rooms are often provided for the timing controller and its associated equipment. Starting blocks and touch pads are sensitive electronic devices which need to be fixed, removed and stored with great care. Special trolleys are available to allow their convenient collection and transportation to storage.

Scoreboard

Finally, careful consideration needs to be given to the location and fixing of the scoreboard, as it should be clearly visible to all the spectators and typically weighs over 200 kg. Advice on scoreboard location, and on other issues to do with automated timing and scoring systems, can be obtained from the ASA.