Race timing equipment ideas

[East Bay Rich]

With the Sandhill Spring series right around the corner, I've been thinking about their grassroots-style timing. It's usually a person w/ a stopwatch. This leads me to ask:

What alternate methods could be implemented?

Idea #1 Instant Replay:
I came across a DIY instant replay system comprising of a TV, DVR/TiVo, & video camera. Set the video camera as the DVR input and you can have instant reply. Set up a large digital clock w/ milliseconds in the foreground of the camera and you can check to see exactly when a racer crosses the finish line. However, the review time would be slow and would require quick math to calculate the true differential. It would also depend on the replay & slo-mo ability of the DVR.


Idea #2 Electronic Finish Line:
What if we took a stopwatch, and modified the start/stop button? Instead of the signal coming from the little button that you push, it could come from a strip of Ribbon Switch:
Tapeswitch Corporation Online Store - Safety, sensing, and signaling products
The big problem is that bikes would press the switch twice, once per wheel. This student had a solution:
Bicycle timing system for sprints and time trials
If we were to eliminate the double input from two wheels, it might even be possible to wire a start-input at the start gate.

Idea #3 CPU timing system:
This would take ideas from #2, but add in a digital timer program. Perhaps the program could be written to ignor the rear wheel input.



De-Bouncing elimination ideas:
1.) What if the switch is held down after the first wheel passes over, and is released when the rear wheel clears the swtich? Perhaps 2 pieces of flat wood that sandwich the switch?

2.) What if the switch ran lengthwise or diagonally under a piece of wood that was longer than your average bike wheelbase? It wouldn't be depressed until the bike clears the board, right?

Well, if you have any ideas PLEASE post! This comes from a racer that has won and lost heats by fractions of a second ; )

Thanks,
Rich

[mudanoman]

Those are some good ideas!

Stop watch and instant reply could be used in combination if there are times that are close calls [times that are within the same second]

I was thinking about the physically triggered switch but that could have limitations if the rider does not trigger it for whatever reason (pedal wheelies at the finish, does not apply enough pressure to trigger it). Also will need to be built to withstand extreme use.

Another idea could be using laser triggered timers. The circuit should be pretty straightforward (idea: EVENT TIMER PRO). The drawback is the laser's operation in daylight or lack thereof.

Best case is if there is a trigger unit at the start and at the finish. Times are recorded and the difference is the rider's time, all done seamlessly in Excel or similar program.

Then again depending on the size of the race there will always be the need to have human supervision in the case of passed riders / dropped out riders which will inevitably introduce human induced errors.

Perhaps the basic stopwatch in combination with instant replay is a worthy contender given the simplicity and accuracy when needed.

Btw, sucks to lose by msecs :-P

[Nemesis Gnat]

freelap timer system? why reinvent the wheel?

[East Bay Rich]

Cycle Logic :: Freelap
True, solutions already exist, but I'm looking at budget ideas. A used DVR runs $20-30 on CL. The TV and Video camera I can use for free at work. Seeing how funds are low, I'm looking at low-to-no-cost solutions. That's a good point that Instant Reply could be used to check for human-error or lag.

I'm also thinking a budget system could be used for "Dash-for-Cash" events through the rhythm section on the SHR 4x course.

Thanks for the replies so far-

-Rich

[Brian B.]

Have you tried posting at mtbr? I figure someone there would know of something that would work.

I've seen them set up some sort of timing system at the PAL track using a laser, I am guessing, at the bottom of the starting hill to see who could do the fastest gate start.

typed in timing system on ebay and saw this

ACCUTRACK Track & Field Timing System ~ Speed Trap ???? - eBay (item 300291279735 end time Feb-08-09 08:47:36 PST)



how about this???

Tutorial: How to Make a Cheap Personal Lap Timer - Mini-ZRacer.com Forums

[East Bay Rich]

I finally found a cheap TiVo, but read up online and discovered that I'd need a subscription just to operate it. Blah.

I couldn't sleep last night and at 4 am, I realized I could use a freebie stopwatch program and two mice. I found one called XNote Stopwatch:
XNote Stopwatch - Free software downloads and reviews - CNET Download.com
This program has a de-bounce feature, so it might be able to account for two wheels.

Interestingly, I can connect a Serial input, so the tapeswitch idea might still work, but they're $35-$40. Using free, old mice appeals more to me.
I'm dismantling old mice to try to build a switch of my own. Wish me luck : )

[mudanoman]

Interesting. You could sync the computer time and start time, have predefined start time slots, record the finish times on laptop. Plug into Excel and do some subtraction. Still some error however.

How would the mouse button be triggered?

Also I think all you need to record is the first trigger time which will most likely be entered immediately into some sort of spreadsheet by the race official since there is usually some time in between riders. De-bounce is nice but probably not needed as it can introduce other headaches if its doesnt work properly.

Just my .02 -- stuck at the office waiting for files to arrive :0

[East Bay Rich]

I haven't figured out the trigger for the mouse yet.
It occured to me that I can probably use garage door sensors at the finish line. I can probably hack a serial COM cable, and connect the leads to the sensors. My concern is that the Photo cell senso will trigger off and on as the bike passes through the light field. Maybe I'll track down a used on on eBay and test out the theory.
-Rich

[Nemesis Gnat]

will that still fit your objective of being cheaper than an existing off-the-shelf timing system?

[East Bay Rich]

Originally Posted by Nemesis Gnat

will that still fit your objective of being cheaper than an existing off-the-shelf timing system?

So far, yes- it will be cheaper. A garage door sensor is $20-40. The software is free to try, $24 to buy. I got a COM serial cable from work for free and can probably hook up one for the blue and one for the red lane. I'm still looking for laser/photo sensors (Event Timer Pro sells their kit for $50). The wiring looks reasonable.

Event Timer Pro and Freelap timers systems would cost over $300.

The tough part would be coordinating the start time at the top of the hill. Running wires to the top would be impractical, and remote start timers would require more technology. Predetermined start times seems like the best solution if we were to record top-to-bottom run times as opposed to lane split times.

Thanks for all the input so far!
-Rich