There is an extreme advantage to using an electronic finish line. Arguments over race results evaporate as the "human error" is removed and results are accurately determined, meaning that it is fairer to the racers. If you are interested in having an electronic finish line, then you are left with 2 choices, buy or build. Below is information on commercially available systems.
If you don't have someone in your organization that could build an electronic finish line, and you have the budget, here are some commercially available systems. I have no direct experience with some of these systems, so I just summarize information from their web sites.
Items to consider:
- Cost - The cost is generally dependent on the number of lanes, how the results are displayed, whether you want a computer interface, and other options. Some of these systems are available in kit form so you can do some of the assembly to help reduce the cost.
- Timer Precision - A timer should have a timing precision of 0.001 or 0.0001 seconds. To put that in perspective, 0.001 seconds equates to about 1/8" of separation between cars. Less of a timing resolution and you will get a higher chance of ties. With a higher resolution you increase the chance of measuring "noise", like variations in the operation of the start gate, bumps to the track, etc..
- How Results are Displayed - Some merely indicate the finish order via LED's or a single digit display, while others actually display the elapsed time. With these displays you don't need a computer interface to use the timer. If you can afford it, I would recommend using a system that indicates the finish order by single digit display or by elapsed time. Telling the finish order by simple LED's that are either on, flashing slowly or flashing quickly can be a bit confusing and you may end up spending a lot of time explaining what they mean to parents.
- No Display Systems - A couple of timer manufacturers have come out with inexpensive timers that doesn't display the race results at all. You must use a computer with these timers in order to see the race results. I'd caution about using one of these timers for a race. If you run into a problem with getting the timer to communicate with the computer, you have no Plan B fallback. If the timer had a results display, the worst case scenario would be that you could resort to paper and pencil to get through your race. Personally, I feel that these no display systems are more suitable for those people with their own test tracks, instead of being used at an actual race.
- Computer Interface - Some systems have the ability to interface via a computer's serial port, so you can use race management software to keep track of the times and manage the race, others systems don't. This option may come as an added charge.
Note: If your computer doesn't have a serial port, then you will need to get a USB to Serial Adapter. With these adapters there will be a driver that you must install on your computer which will get the USB port to behave like a regular serial port.
- Computer Software - Some timer manufacturers offer their own software at an additional charge or make their timers compatible with some commercially available software packages. Check if they have a free demo that you can try out before you buy, as no one program will fit everyone's needs.
- Type of Finish Sensors - To get the finish signal from the lane, these systems use infrared (IR) sensors, regular photo sensors, mechanical switches or sensor flags. Infrared sensors are the best option since these are less susceptible to interference by flash photography. Though, if you hold your race outdoors, an IR system may not work due to bright sunlight (the sun is a great IR source). Systems that require you to provide a light source for the sensors, do need sufficient incandescent lighting, so you may need to provide one or more light fixtures. I do recommend that you stay away from systems that use mechanical switches or sensor flags, as these have a higher likelihood of failure or alignment issues.
Electronic Timers: - In alphabetical order.
- Derby Timer - Derby Timer offers affordable 1 to 4 lane timers. Dual sided display (times and finish order on the front, finish order on the back). Compatible with GrandPrix Race Manager software.
- Fast Track - Micro Wizard offers 3 different models of their Fast Track timers. IR sensors are used and their newer timers time out to 0.0001 seconds. They are also available in kit form, if you want to save a bit of money and don't mind some simple assembly. Compatible with GrandPrix Race Manager and some other race management software.
- NewBold Products - Their Turbo timer use IR photosensors, while their Turbo Lite and DerbyStick timers require you to provide an incandescent light source for the photo sensors. With the Turbo, results are displayed with large numerals above each lane. The Turbo Lite displays results on a handheld unit. The DerbyStick has no results display at all, so you must use it with a computer. Claims a precision of 0.0001 seconds. With the Turbo Lite and DerbyStick, since the sensors are not mounted in an enclosure, you can use this timer for other types of races like Space Derby and Raingutter Regatta. Compatible with GrandPrix Race Manager and some other race management software.
- RaceMaster Timer - A 2 to 6 lane timing system, available through the Awana and Gospel Publishing House catalogs, fitting tracks with 3-3/8", 3-1/2" and 4" lane centers. Displays elapsed time, but only out to 0.01 seconds, however, when used with race software it will transmit times out to 0.0001 seconds. The RaceMaster IV model has the ability to interface with a computer's serial port, earlier models do not. Compatible with GrandPrix Race Manager (RaceMaster IV model only).
- SmartLine - Timers for 1 to 8 lane tracks. Claims a precision of 0.00005 seconds. They also carry a USB video capture device which snaps a photo finish picture at the instant the first car crosses the finish line.
- SuperTimer - Uses a mechanical sensor flag that is hit by the car as it crosses the finish line. They claim this sensor can withstand millions of hits without damage. However, from the pictures on their site the sensors can get slightly bent, so all of the sensor flags may not line up well, meaning that the lanes with the flags bent less actually have a slight advantage. Finish results and times are announced audibly, though they also support a computer interface. Only their software (rather expensive at $99) will work with their timer. Timer precision is claimed to be better than 0.0001 seconds.
- Swanberg Technologies - A very simple modular IR system where you build the housing for the electronics and then wire the units together. There is no computer interface available and timing precision is only 0.001 seconds.
- The Judge - An IR system that comes with a stopwatch or computer interface options that allow display of times out to 0.0001 seconds. They do also have their Transponder timer that is an inexpensive option and comes with or without a finish order display (I recommend getting the display). They offer used or older models at reduced cost, or you can rent a unit. They also offer a version that works in sunlight. Compatible with GrandPrix Race Manager and some other race management software.
- Timestoppers - They have a couple of models that use an incandescent light source (you provide) and regular photo sensors for finish line detection and one the uses photosensors with "collision blocks". The collision blocks have a flag on the bottom that blocks the photosensor. When the car hits the soft foam block, the sensor becomes unblocked. The blocks flying around would probably be cool for the kids, but you hope you don't lose them. They have added a computer interface to a couple of their models. Timing is out to 0.001 seconds.