Low-cost home-made timing system and tape switches

[Pat Chewning]

I'll follow up with more details later, but I just finished up building a two-lane timing system for our races.

Attributes:
Low-cost
Electronic circuit to ignore the back wheels and only trigger on the front wheels.
Disected stop watches are the source of the timing. These are matched in time and voltage source so they don't differ by more than .01 second over a 5-minute timeframe.

Home-made tape switches which are very low in profile and will trigger at approx 30 lbs of loading on a skateboard. These are constructed from two strips of .006" thick stainless steel separated by a .060" thick mat used for kitchen cupboard lining (with holes to let the strips come in contact under pressure). This is then sandwiched between .006" thick vinyl sheets and glued together.

The START of the timing system has a dual-mode switch, MODE A is to trigger both starts simultaneously with a tone. MODE B is to trigger each start independently with a tape switch.

It works on my kitchen floor -- we'll have to see how it works out on the hill. My daughter and I are timing each other on trips around the cooking island.


PS: No, I will not build you one. I will give you the plans for it though. The documentation should be done in about a week.

The full documentation for the timing system is at: http://www.pgrass.00sports.com under the "Links/Contacts" page -- at the bottom.
-- Pat

<font size=-1>[ This Message was edited by: Pat Chewning on 2003-05-13 01:35 ]</font>

<font size=-1>[ This Message was edited by: Pat Chewning on 2003-05-13 01:36 ]</font>

[Tom Blankley]

Pat, your timing system sounds great. I'd like to see the specs. so I can build one.
I'll see you June 28th, The races sound like a lot of fun.

Tom

[Leonardo Ojeda]

I am definitly IN for that kind of timer!

how much do u think it will cost to build?

leo

[Pat Chewning]

The timing system has been to the hill a couple of times, and I'm pleased to say that it works well.

I finished documenting the construction of this system and will make it available on http://www.slalomskateboarder.com as soon as I figure out how to get a MS WORD document to show up here on the site.

A couple of things I did learn:

1) 500' is not enough wire
2) Wire is expensive, but will work with any timing system (should I ever upgrade to a Trackmate system).
3) Duct tape, when run over with several dozen skateboard wheels will stick like glue to soft materials (e.g. the outside of a tape switch)and will be nearly impossible to peel off.

Article to appear here soon, somehow.

In the mean time, send me email if you want documentation on the build-it-yourself timing system and tape switches.

-- Pat

The timing system documentation is at: http://www.pgrass.00sports.com under the "Links/Contacts" page -- at the bottom.



<font size=-1>[ This Message was edited by: Pat Chewning on 2003-05-13 01:38 ]</font>

[Glenn S]

<a href=http://www.slalomskateboarder.com/Stuff ... System.doc> Timing System MS Word Document</a>

<font size=-1>[ This Message was edited by: Glenn on 2003-07-14 01:58 ]</font>

[Dan Loveland]

I just wanted to vouch for Pat Chewning's Home Made Timing System. Super cool!
It works everytime we go out skating!
It is so nice to know your time so you can make improvements. It is the only way to tell if you are getting better. Thanks, Pat

[Pat Chewning]

I am just about finished with a prototype of a new timing system, better than the 1st one I built. This new one has several improvements that will make it easier to process the results, more versatile, and easier to change. I'm calling it Chrono-Cone 2003 .

One of the big problems I had in running our 1st race was accurate recording, summing, applying cone penalties, selecting best times, and ordering of racers based on the results. It made me think that a computerized system is the only way to go. So I brushed up my Visual Basic programming skills, wrote some code, tore apart a keyboard to interface to tape switches, and came up with "Chrono Cone 2003" -- a much improved homemade timing system.

1) Laptop computer based system.
2) Uses the same tape switches and wiring as version 1.0
3) MUCH easier to wire and build. (4 wires go into a disected keyboard).
4) Other than the laptop, MUCH less expensive. (Keyboard only costs $13)
5) Extensible for future functions: Tone race starts, false start detection, etc.
6) Automatically gathers racer's names from an ordered input list, stores the raw time, cone penalty, resulting time, and DQ into an Excell spreadsheet for further automatic processing.

The code is written for Version 1, and works using simulated starts/stops from a keyboard. The keyboard wiring to the tape switches should be done by the weekend, then I can give it a try.

As with the 1st timing system, I will make the resultant documentation available here once it is more perfected. I MIGHT be convinced to build some of the keyboard/tapeswitch interfaces and customizations to the program in trade for skateboard equipment.

I've been reading the posts about starting individually or commonly, with X number of tones, false start detection, etc. I can say with confidence that all of these things are "simply a matter of code" for Chrono-Cone 2003 and can be added with a couple of hours of programming effort.

But first -- let's see how it works on the hill.

-- Pat

<font size=-1>[ This Message was edited by: Pat Chewning on 2003-05-13 01:56 ]</font>

[Dan Loveland]

Pat the plans do not load on the grassroots website. Maybe you new this. Please post the circuit that is used to make the switches not trigger on the back wheel. It is killing me trying to figure this out. Thanks, Dan

[Glenn S]

I asked Jani to host the original Word.doc that Pat sent me. The link to the download is above.