The mobile supercomputer

Automobile crossing rope bridge

Automobile crossing rope bridge (Photo credit: The Field Museum Library)

Maybe it’s my fading memory, but I seem to remember that winters were much colder during my school years. It could be that I spent a lot more time standing around in the snow waiting for buses, but the cold used to seep up through my shoes and into my bones. You didn’t need to look out of the window to see whether it was a cold and frosty morning. The starter motors of the reluctant cars made a characteristic whining noise in a gradually slowing rhythm as the last dying remnants of the battery was eaten away.

In the early 1980s, the ignition systems in cars were mechanical in nature. This meant they had the annoying habit of wearing out at the most inconvenient moments. Not only that, but there wasn’t much adjustment available. It didn’t matter whether it was 30 degrees and sunny or -20 degrees with inches of snow on the ground, the components in the ignition system worked (or rather didn’t) in exactly the same way.

The only tool available to the driver was a little knob called a choke which pulled out of the dashboard and controlled the strength of the fuel mixture. On a cold and frosty morning a richer mixture was required. As the engine heated up, the choke could be pushed gradually back in returning the mixture to normal.

Ford assembly line, 1913.

Ford assembly line, 1913. (Photo credit: Wikipedia)

Electronics were not the only reason cars were unreliable. The assembly lines on which they were produced had not advanced significantly since Henry Ford came up with the idea. Although many parts were pressed out of steel using a massive die, almost everything was assembled by hand which meant that fit and finish were inconsistent. Some cars were more reliable than others and there was a suspicion that quality of assembly went significantly downhill towards the end of the working week. If you were unlucky enough to have bought an unreliable car, people would refer to it as a “Friday afternoon car”. The metals used in car construction were nowhere near the quality of those used today. In addition, galvanisation had yet to take off and few car manufacturers used sufficient rust protection. Even if your pride and joy was in fine fettle, the dreaded tinworm could have nibbled its way through crucial parts of your car’s anatomy.

Construction techniques have advanced and cars have undoubtedly made massive leaps forward in terms of comfort, reliability, efficiency and safety but the basic form factor has remained the same for about a hundred years. The biggest leap forward has been in terms of the sophistication of the electronic control systems watching over the engine, brakes and suspension. It is not uncommon for a premium car to have 20 – 30 micro controllers and 100 million lines of code buried under the considerable bonnet (or hood if you’re American).

Just to put those numbers in perspective,  according to the Mythical Man Month (required reading for anyone in software) it is estimated that developers on average produce 10 lines of code per working day. I’m assuming that car manufacturers must find more productive programmers otherwise writing the software for a car would take approximately 50,000 man years. Of course not everything is written from scratch and the same code must get reused between different components and different cars. Still, it’s an incredible amount of software and not only that, the quality seems very high which is a comfort when you stamp your feet on the brake pedal in the rain.

I’m just glad I don’t have to listen to that infernal racket on a cold and frosty morning.

One comment on “The mobile supercomputer

  1. I wonder how the Monday morning cars compared. After all, first shift going back after the weekend, was the quality really there in their work yet? Did they need to warm up to it? These are things I ponder. We’ve come a long way. We love to enjoy our old cars, but sometimes we don’t want to wait for them to warm up. Thanks for the link. 🙂

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