I've owned my 1999 Mercury Grand Marquis LS for a little over a year now. Before that, I drove a 1992 of the same make and model. The '92 had the digital instrumentation panel, whereas my current car does not. I found the digital panel easier to read, as I learned to be able to read my speed out of the corner of my eye, since the numbers were large and glowed bright green. For this reason, and the fact that my car has no tachometer (which I would like to have for no particular reason), I have decided to build and install a HUD (or Heads-Up Display) into my car. Aside from providing more info and having cool factor, the HUD should increase safety since all pertinent dashboard information will become the same field of view as the road, increasing reaction times. However, should the HUD prove distracting/illegal in certain areas, it will be able to be switched off, and the original instrumentation should not be tampered with.
| Project completion & status: | ||
| Initial Design: | 10% | Some thought has been put into how a HUD might work, and fit on the dashboard. |
| Overall: | ?% | I have no clue how this will work yet, and so I can't quantify progress. |
In the last few days I have acquired some limited information about other cars which come stock with HUD's, and how they work. I have also seen two or three aftermarket kits, although all of those have been for turbo timing and such. All of them seem to use some sort of diffusive plastic or tint on the windshield to facilitate consistant display conditions. I believe all of them use LED's as the light source, although I'm going to look into a scanning laser-type system as well.
I've discovered that all vehicles sold in the U.S. after 1996 have a feature connector in them which is fairly standard and links a serial port device directly to the car's ECM (Electronic Control Module) bus. This can provide valuable data such as vehicle speed, engine speed, engine load, fuel mixture settings, and others. I'm uncertain if fuel level is provided on this bus or not yet. If not, it will simply not be included on the HUD, as fuel level does not need to be constantly checked while driving.
I've also purchased some LED's from Radio Shack, along with some batteries and resistors, and I've tried out a 3000mcd red LED and a 1500mcd yellow-green LED. The red, running at full power, was fairly visible on my bare windshield during overcast conditions, and incredibly visible at night. The green LED was barely visible in daylight, but subtly noticable in darkness. A side effect noticed from the LED's reflection is that my windshield apparently has more than one layer of material (glass, etc...) in it, since the reflected image has a tendency to "ghost" two or three times. I am currently hoping that some tint or other form of translucent surface will reduce or eliminate the ghosting.