Now, this is cool. A few weeks ago, I discussed how a digital instrument cluster can provide
visual cues to help drivers avoid speeding. For instance:
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Well, guess what. Engineers for Chryler's now-defunct Plymouth division came up with this concept years ago — in 1939, to be exact. That's the year Plymouth introduced its "safety speedometer" in the
P8 model line.
From what I've read, these speedometers switch from green to amber to red, depending on the car's speed. I've only seen still photos of these speedometers, but allow me to invoke the magic of PhotoShop and reconstruct how I think they work.
The safety speedometer has a rotating bezel. Embedded in this bezel is a small glass bulb. At speeds from 0 to 30 mph, the bulb glows green:
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At speeds from 30 to 50 mph, the bulb turns amber:
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And at over 60 mph, the bulb turns red:
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Of course, given the limitations of 1939 technology, the Plymouth safety speedometer can't take driving conditions or the current speed limit into account. The speedometer glows amber at 30 mph, regardless of whether you're driving down a quiet neighborhood or on a busy highway.
Compare this to a software-controlled digital speedometer, which can take input from multiple sources, both within and outside the car, to provide feedback that dynamically changes with driving conditions. For instance, a digital speedometer can acquire the current speed limit from a navigation database and change its display accordingly.
Also, a digital speedometer can intelligently deemphasize unnecessary information to reduce driver distraction. For instance, it can dim any gauge that is displaying values in the normal operating range. Like so:
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Mind you, I'm just scratching the surface of what a digital instrument cluster can do. Check out
Andy Gryc's new whitepaper to get a better idea of how automakers can implement — and benefit from — this technology.
p.s. I can't locate the website that contains the original, pre-PhotoShopped photo of the safety speedometer depicted in this blog post. If you recognize the photo and it's yours, let me know, and I'll give you the photo credit and link to your page.