Simplified Least Expensive Timer(with images)

DIY timing systems
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Pack11SanDiego
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Joined: Sat Feb 11, 2006 8:58 am

Simplified Least Expensive Timer(with images)

Post by Pack11SanDiego »

Hello Gang; nice forum here!

This is a simplified version of the World's Least Expensive Pinewood Derby Timer, by James H. Brown, found at
http://pinewood.hmpg.net/

When used with Mark Logan's free Racetimer software, it nicely automates many of the routine tasks of running a race. You can even
import heats generated by Stan Pope and Cory Young's HeatGenerator webpage.

There is a discussion and support group with free copies of software and many knowledgeable people to help with any questions at
http://groups.yahoo.com/group/PinewoodTimer/

**************************************

When I built my first setup, I learned I could use the +5v off a USB port to power the pull-up resistors and actually solder those resistors inside the printer plug, completely eliminating a separate power supply/circuit board.

Then I forgot to plug in the USB power pigtail one day, and it worked just fine. I discovered that most modern(WIN98>) computers already have the pull-ups included with the printer port. I have tried the setup without pullups/power supply on various laptops and desktops
running at least WIN98, and it worked on every one.

**************************************

Parts List(suitable ones pictured in accompanying image)

-Infrared Phototransistor(light sensor) Radio Shack #276-145. One for each lane.

-Start switch

-Modular(stranded) telephone wire; 100'. For lane sensors and start switch.

-Parallel printer port plug. It's made up of two parts; a DB-25 male/solder connector, and an accompanying hood.

-Soldering iron(very small) plus solder(rosin core)

-Some heat shrink tubing(to insulate switch pins/sensor leads)

-A regular 100w light bulb in a clip-on receptacle. We attach ours to a sloped receiver box which automatically returns the cars, and houses our monitor stand for finish line results.

Here is a picture of all that you need(besides a computer) to build your own timer setup.

Image

You can solder both the start switch cable and the sensor array cable directly to the printer plug. The correct pin numbers and plug orientation are included in the images. We have a 3-lane track.

It is possible to support up to 7 lanes using what are called the "status" bits, or up to 4 lanes using the "data" bits of the parallel port. The status bits require that the port be "ECP" capable, which most computers from WIN98-onward are.

Here are the pin numbers:

START pin 2 or 15
LANE1 pin 3 or 13
LANE2 pin 4 or 12
LANE3 pin 5 or 10
LANE4 pin 6 or 11
LANE5 pin 7
LANE6 pin 8
LANE7 pin 9
GROUND pin 25

Note that the plug illustration is the female(on your computer) from the front, so this is the same perspective that you will use to solder the male connector from the back. Easy.

The back of the phototransistor package shows which lead is the collector(without the arrow on it in the schematic; the short lead/flat edge on the plastic housing) Each collector wire and the
start switch are soldered to the appropriate signal pin. All the emitters are then tied together(along with the other side of the start
switch) and soldered to ground pin 25.

Be sure and slide a piece of heat shrink tube down one side of the sensor/start switch leads BEFORE you solder them. Heh.

FABRICATION

The *first* thing you want to do is decide where your computer will sit, as this will determine the lengths of your sensor and start switch cables. We locate ours at the start end, so our sensor cable is about 40' and our switch cable is about 15'.

Here is a photo of perhaps the trickiest part; stripping the stranded phone wire before soldering. It's very easy to break a few of the
strands, so you'll have to practice a little to get the hang of it.

Be sure to count the strands after you strip; one or two missing might still work. For Sure you're going to want every one present on the ground wire, which is usually colored BLACK.

Image

Here you see pin 25 about to be soldered(the plug is inverted) with both the sensor array ground, and the start switch grounds(I twisted
together 2 wires each for the start switch signal/ground, since only two wires are necessary there.)

Image

Here is the printer plug just about to be closed up; note the strain relief fitting which grabs the wires tightly and fits into a recess. It keeps jerks on the cable from pulling on the solder joints; important.

Image

Here is the completed cable assembly with printer plug, start switch, and sensor array. A clip-on light provides illumination to test the array; Racetimer is running in the background.

Image



To install the sensors in your track, drill holes the EXACT diameter of the light sensor bodies in the middle of each lane, and press the sensors into the hole. You must provide about 1/2" of clearance underneath to allow for the bend you will put in the sensor leads themselves.

We did this by taking a 1/2" piece of plywood the width of our track, and routing out a space to accept the sensor array.

Here is a photo of it being placed on our track.

Image

You also need to install the start switch in a manner consistent with your track's start gate.


Once you have your cables/plug soldered and set to go, you can download the 3 pieces of software(and a webpage for heat generation)
from the yahoo group(separate URL for the heat generator.)

The 3 pieces are the Racetimer.exe itself, some .dlls used by it(you will have to unzip them using Winzip or similar into the SAME FOLDER
as Racetimer.exe; there are 4 of them unzipped), and a program called port95nt.exe, which is run just once to install it on the machine. It allows the Racetimer software to access your printer port.

You also need a copy of Initialization.htm, which is the file format your results are saved in.

For a copy of the latest version of Racetimer.exe(172kb)(which
supports heat imports), the .dlls(1346kb), and the initialization.htm(1kb) file.
http://groups.yahoo.com/group/PinewoodT ... 0Software/

For a copy of port95nt.exe, which allows parallel port access for Racetimer.exe.
http://groups.yahoo.com/group/PinewoodT ... RaceTimer/

For a copy of the Heat Generator(which is actually a webpage>>>click file, save as, webpage complete, and put it in a folder. Javascript must be enabled in your browser for it to work.)
http://members.aol.com/StanDCmr/ppngen.html


USING RACETIMER PINEWOOD DERBY SOFTWARE FOR WINDOWS

The way you use the program is pretty straightforward. When you open the RaceTimer.exe executable you must specify an existing .xml file in the open file dialogue(If you specify the executable instead in the open file dialogue, the program bombs.)

Make a copy of the existing one(in the Racetimer folder) marked Initialization.htm and select that copy to open when the program asks. That way you still have the "master" initialization file to run with next year.

Proceed from left to right using five different tabs, which are Track Setup, Edit Racers, Edit Schedules(heats), Race, and Results.

Use the "Test" function under the "Track Setup" tab to verify the software sees the light sensors/start switch change states, enter all
your racers, import heats, and you're set to race.

When you exit the program all the results are saved in an .xml file, with the file name you specify using File>New.

HEAT GENERATION

To generate a chart: Use the generator located at
http://members.aol.com/StanDCmr/ppngen.html

Save it in a folder as a complete webpage, and you will be able to use it offline. We generated a chart for each possible number of kids in a den from 3 to 10, and keep each of those text files ready to go in a folder. That way we don't have to mess around with generation at Race Time; we just select one of the pre-prepared text files.

It opens with either IE or Firefox browser; javascript enabled.

1) Title doesn't matter; only the text generated by it is used by Racetimer.

2) Enter # of lanes. We currently have three.

3) Enter # of cars FOR THE DEN YOU ARE SCHEDULING. You generate separate schedules for each den.

4) Enter # of rounds. This is equivalent to the # of times a racer is in each lane. We use two.

5) Choose the "Tab-delimited Text" option.

6) We use "medium" weights for all three "Heat Ordering Options", with excellent results.

7) Copy and Paste the 'heat' information ONLY into a text file.

Be careful to grab the data as tight as you can, as it bombed the program when I included the little numbers above the table. Likewise
if I didn't save the text file before attempting the import.

Remember where it is.

IMPORTING HEATS

8)Run RaceTimer.exe and add all of the racers (if not already done).

9) Go to the "Edit Schedules" tab, choose group and round.

10) Hit the 'Import' button and choose Partial Perfect-N (Tab Delimited)

11) Select one of the pre-prepared files or the file you just created and hit OK.

12) Have a look at your newly created heats - nice aren't they?



EXTERNAL MONITOR

Use an external monitor for the kids/parents to watch!

At the finish line we have a table to set up a big monitor, with the laptop controlling the race from the starting end.

Everyone likes to watch the monitor to see who wins and what the scale "speed" is. You can usually toggle the display by hitting F3 on a laptop.

Here is a photo of our finish line setup, with the lamp holder for the sensors, and a monitor stand.

Image

Cheap source for 50' monitor cable.

Image


I hope somebody finds this useful. The images are hosted at pixpond.com, which dumps them once a month. Please let me know if anybody would like them re-loaded.

Mark M.
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Cory
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Re: Simplified Least Expensive Timer(with images)

Post by Cory »

Pack11SanDiego wrote: You can even import heats generated by Stan Pope and Cory Young's Heat Generator
Just an FYI...the functionality contained in the web based generator also exists in a Win32 dynamic link library. The DLL is freely available. It's already being used by a number of race managers, both commercial and non-commercial.

Get in touch w/ Stan or me if you're interested.
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