Anyone ever build a lap timer....?

[jxxxoxxxe]

So I've had this crazy idea that I want to build a lap timer for more accurate results than clicking the ol' stopwatch....I've got an idea, but thought i'd see what everyone else thought...

I was thinking of trying to use the eyes from a garage door opener as the trigger mechanism. I figure they work off mV, but haven't got the voltmeter out yet to test mine...I figure they could be ran to some sort of relay or transistor to start and stop a simple stop watch. I would power the eyes with a battery and resistors....Am I out of my mind? or would something like this work?

A normal garage is what, 16 feet wide, so that would be plenty of space to pass through...

 

[e-tek]

What are you timing?

 

[speed bump]

Never had the need to build one but its easy enough depending on what you want to do. If you just want one lap get a sensor that trips when you break the beam and then build a simple timer circuit that instead of a button turns on and off based on the sensor opening. If you want something slightly more complicated I would pick up a Programmable Logic Controller, put the code in it, wire it up with the controls you want and go from there.

If you really wanted to I bet you could also just take a stopwatch and replace the buttons functionality with set of photo resistors and maybe a a simple logic controller to make sure the right buttons always got pushed.

 

[Jack Olsen]

Would you be the only car on the track?
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box vaporizer

 

[Slick6]

If you're comfortable with electronics, you can pick up a light/dark detecting kit and do a little more external wiring and I think you'd have something workable. It would be much easier with a PLC, but the cheapest programmable logic relay device I know of is about $80. So we'll look at this.

The light on the left would be controlled by your garage door sensors as the switch for the light. From what I've seen, some sensors are normally open and some are normally closed. Providing your door sensors operate on about 12 VDC you could pick up a ~ 12V rechargeable drill battery to power it with and have a compact and moderatly cheap setup. But I wouldn't get too far without making sure your sensors can detect signals that far apart and out in broad day light.

And about midway through this I realized it's about a month old, but what the heck, I decided to just finish it.

Note: This is coming from material learned in a Electronic Devices course. It might work, it might not. But, the few bucks in material I think would be worth the learning experience even if it doesn't work.

EDIT* And then I realized that your rear wheel would restart the timer. I'd have to look into it a little more for that.

 

[crashbumper]

I haven't used one in a project yet, but I always see the Arduino mentioned as one of the most versatile platforms and easy to program and use.

Arduino.cc

 

[jxxxoxxxe]

EDIT* And then I realized that your rear wheel would restart the timer. I'd have to look into it a little more for that.

Thanks for the info...


You could actually put the sensors high enough that the car body broke them, and not the wheels/tires...

I need to look into this more...

 

[Slick6]

I'm going to check out those Arduino units. There's so much stuff out there that I have no idea about. (Just getting started in an electrical career.)

These are the PLR's I was mentioning with an LCD display and keypad.
http://www.factorymation.com/s.nl/sc.2/category.1296/.f

Raising the sensors to car panel height makes sense.

 

[toadjammer]

Slick
That is a cool picture, where did you find it at?

 

[Slick6]

On a truck website. www67-72chevytrucks.com

Here's a little bigger one. With a bonus Camaro & C-10 picture.

 

[Vernmotor]

gezz you think he might like chevys LOL

 

[crashbumper]

I just saw this; pretty darn close to what you are looking for!

Real-Time racing telemetry with the Make controller

http://blog.makezine.com/archive/2009/04/real-time_racing_telemetry_with_the.html

 

[Red Green]

http://www.longacreracing.com/catalog/item.asp?id=274&catid=10 I bought one from Longacre for myself it was more cost/time effective to buy one rather than try to build it.

 

[ilikebeer]

A plc would work great are you using the lap timer for quarter mile or a real complete lap? If you did the quarter mile you would need a eye for the start and finish if your doing a complete lap you could do a flip-flop circuit.
This brand of PLC has the programming software free also if you used the small panelview this software is free as well.

http://web6.automationdirect.com/adc/Shopping/Catalog/Programmable_Controllers/CLICK_Series_PLCs_(Stackable_Micro_Brick)/PLC_Units/C0-00DD2-D

and this
http://web6.automationdirect.com/ad...Graphic_Panels_-a-_Keypad_Bezels_(3_inch_only)

Whoa! by the time you by a photoeye or two you might be better off looking for a package deal unless you looking to experiment.

 

[Jack Olsen]

Hot Lap is ancient technology and overpriced. It also shakes apart and fails, sooner or later.

Ultralap is a huge improvement. Many more features than the Hotlap.

http://stores.sportbiketrackgear.com/Detail.bok?no=30
or
http://www.apexperformance.net/cartgenie/prod-1085.htm

Nowadays, though, there are iPhone apps that can gather a lot of data, including lap times.

http://tomatounion.com/
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silver surfer vaporizer