Starting light working group

[walterclark]

I now have the IO board (the interface between everything and the micro-controller) built, tested and installed in the traffic light along with the micro-controller and the LED lights. It works beautifully and looks GREAT! I built troubleshooting LEDS onto the IO board so one can see the controller operating the big lights before the drivers and relays, the start switch operating and the electric eye operating. I also built in a spare driver and relay (the only electro-mechanical things in this traffic light and thus the most likely thing wear out over time) so if one fails all you need to do is change a jumper on the one that is failing and move a wire on a screw terminal to swap in the spare.

I am going to install an eyebolt in the top of the light (in place of the original pipe-T) for the stand Joey is making and I will be making a plate for the 3" hole in the bottom and the electrical connector will be recessed on that plate. When done, the traffic light will be water tight and with just one plug a snap to put up and take down. I am planning to lead the single electrical cable (with 9 conductors) coming from the traffic light up to the top of the stand (for a drip loop and to keep the wire from providing any mechanical support for the light) then down to where the battery tray is located. There the cable will split out for the battery power, Start button, electric eye and comm wire connection. All the connectors will be different so cant be confused.

Some pics:
Traffic light with LED lights installed

Top board is the micro-controller, the bottom is the IO board. It was shot with the electric eye tripped and you can barely see 2 red LEDs on the IO board ON (the eye tripped input and the Red LED light driver on).

The Red LED light ON

I couldnt catch he yellow when it was on...

The Green LED light ON

[jkale]

WOW Walter!! Nice work! I'm pumped for this method of starting cars this year...

[sachilles]

pretty damn cool!

[Mopar 151]

There just ain't enough "Attaboys" for this!

[walterclark]

Info on the hanging eye and bottom connector:

This is the eyebolt installed. It is 1/2" rod. It is 5.5" from top of light to top of eyebolt.

Overall height of the light from bottom of light to inside top of eyebolt.

Connector on bottom is recessed so it wont get damaged when handling or in storage so long as cable is removed first.

[3rdgendennis]

Looks great Walter!

[DaveEstey]

Attaboy!

[jkale]

what are we all thinking for overall height on this stand?

Im thinking the green light at about eye level while sitting in your car...maybe a little lower...

inputs?

[walterclark]

That would seem about right to me. Made me think of something...how are the lights "aimed" in the enclosure, and how does it hang right now?

The LED light units have a fairly narrow viewing area where their intensity is high - a combination of the directional characteristics of the individual LEDS as well as the lens over each light. And the light assemblies have a built-in tilt (as can be seen below). I noticed that the sun shades are mounted at different angles too - with the red being a little more tipped down in front than the green, but I think this could be changed. So, it looks like there is some inherent "aim" to these lights, designed on the assumption they are all mounted above motorists heads. I will do some experiments soon to see if this is true, and what we might do to compensate.

[walterclark]

So, I did some testing.

The lights aim the center of intensity down 7 degrees from horizontal. This is measured when the traffic light is free hanging from its eye and thus includes the fact that that with the sun shades in place the light doesnt hang exactly vertically, rather it tilts the light beams slightly down. The vertical field of max intensity is a vertical area about 8" either side of the center of the beam as seen from about 15' away. Outside that, over the next foot up and down, the intensity drops fairly rapidly from almost-painful-to-stare-directly-into, to gently illuminated (which might not be visible in direct sunlight). Hanging the light with the green lamp at a drivers eye seated height, and positioned 15' away, centers the green beam about 22" below the drivers eye, and the yellow 12" below. To compensate, I cantilevered a 5 pound weight from the traffic light rear at the bottom and found when I moved it 6" away from the back of the light, the beam center angle was reduced to 2 degrees down or about 6" below eye level at 15'.

Conclusions. Ideally, we have a vertical area of 12-18" for best visibility of the lights so we will want to choose a drivers eye height that is in the middle of say where Butch King sits to where Bob D'Amore sits (to pick the probable high and low seating positions in the current crowd). The best solution for light height would be so the beams are horizontal (or parallel to the pavement) and thus not distance-to-light sensitive).

Misc observation. Adding the weight outboard of the light to re-balance it increases the pendulum effect of the light so it swings a lot in still air once moved. I cant see it ever not swinging outside when there is any wind and even without the added weight it will have some tendency to swing. Given the limited vertical viewing angle, we want to minimize or eliminate swinging. Maybe we need to entertain a rigid but limited tilt-angle-adjustable mounting scheme...hmmm