PH Origins: Electronic trip computers


In the 1970s, General Motors was forced into making bold moves. The oil crisis had caused both the government and buyers to focus on efficiency and, in an effort to meet the rising demand and requirements for smaller and more economical cars, GM set about downsizing its entire line-up.

GM's downsizing plans didn't just entail ditching cylinders and cubic capacity - but also physically shrinking the footprint of each of its models. It was a huge gamble; the downsizing scheme was announced in the early 1970s and the company reputedly ploughed $15 billion, over the course of five years, into redesigning all of its cars by 1980.

The changes were significant. GM's brand Cadillac, for example, launched its all-new Seville in 1976. This 'internationally sized' saloon was designed to tackle high-class European imports and, thanks to its smaller proportions, it was easier to drive than preceding full-fat Cadillacs. It was even offered with a diesel, in an effort to appeal to more economically minded buyers.

Not that the diesel was a particularly good effort, mind. The naturally aspirated 5.7-litre V8 pounded out an underwhelming 120hp and just 220lb ft - and the engine itself suffered from several prominent flaws, including a tendency to stretch head bolts and blow gaskets.

The diesel's sole saving grace was that, reputedly, it could average 29 imperial miles to the gallon. The injected 5.7-litre petrol V8, on the other hand, racked up 19mpg. It wasn't just the all-new derivatives and powertrains that were dramatically different, though; the eighth-generation Cadillac Eldorado - introduced in 1979 - was 50cm shorter and 22cm narrower than its predecessor.


This was not going to be an easy sell for a luxury brand such as Cadillac, given that its customers were acclimatised to plush land yachts. It consequently set about employing plenty of tricks to ensure the new models didn't fall short of the expected standards, including design cues that increased the perceived visual size of its cars.

Another key weapon in its armoury was technology. Parent company GM, and Cadillac itself, had a penchant for utilising cutting-edge hardware, ranging from electronic fuel injection through to climate control. After all, perhaps if it couldn't edge out its European rivals on the efficiency or dynamic fronts, cars equipped with the latest and greatest creature comforts could help sway customers back in the brand's direction.

At the time, the availability and capability of microprocessors was increasing exponentially - and the number of home computers was growing at a similarly vast rate of knots. Cadillac was well versed in the hardware, with microprocessors being put to use in the company's fuel injection, ignition and suspension systems.

Showing potential buyers how efficient the car was, and further simplifying life with the car, seemed like sensible propositions - and the application of new, affordable processing power posed one solution: an electronic trip computer. Besides displaying instantaneous economy, the system's capability to indicate factors such as remaining range would help cut down driver workload and stress.

No longer would an owner have to work out potential range and consumption, or other journey details; instead, the computerised system would do it for all them. GM and Cadillac were also of the mindset that, ultimately, all of a car's systems would become computerised and automated - and this would be another step along that path, forming a central point of access for the driver.

The project that subsequently emerged was dubbed 'Trip-master'. The production version, simply called 'Trip Computer' in Cadillac's advertising materials, was an electronic system that could instantaneously report on fuel consumption, range, fuel level, distance travelled, temperature, engine speed, voltage and more.


'Trip Computer for Seville can help make you a more confident driver by providing you with useful information,' proclaimed the adverts. 'How long have I been on the road? What's my average speed? Cadillac's new Trip Computer... answers all these questions and more, with the touch of a button.'

A Motorola 68000-series microprocessor provided the required computing power and opting for the Trip Computer, which was first offered in the 1978 Seville, also replaced the analogue speedometer and fuel gauge with digital readouts. This further modernised the compact Cadillac's interior but you'd pay a hefty premium for the privilege; new, a 1978 Seville cost $14,710. The cost of the optional Trip Computer? A mighty $920. Unsurprisingly, few rushed to take it up.

As hardware prices fell it wasn't long before rival brands began offering similar systems, all of which followed the features and functions laid down by Cadillac's set-up. Mercedes, for example, watched Cadillac's developments with interest - and subsequently set about developing a more refined version in 1984. Even lower-specification cars began to benefit from simplified electronic trip computers, often indicating a remaining range or average consumption.

Even today, electronic trip computers still have their place - and, as electric cars continue to grow in number, that remaining range function is once again becoming increasingly important.

 

 

 

P.H. O'meter

Join the PH rating wars with your marks out of 10 for the article (Your ratings will be shown in your profile if you have one!)

  • 1
  • 2
  • 3
  • 4
  • 5
  • 6
  • 7
  • 8
  • 9
  • 10
Rate this article

Comments (31) Join the discussion on the forum

  • adricmarsh 21 May 2018

    Motorola 68000 went one better in the 1990s when Sega started putting them in thier MegaDrive console nerd

  • Turbobanana 21 May 2018

    "that all-important remaining range function is once again becoming increasingly important"

    It's important to realise how important it is to use the word "important" when reporting important articles like this. This is important. Its importance cannot be overstated.

  • Lewis Kingston 21 May 2018

    Turbobanana said:
    "that all-important remaining range function is once again becoming increasingly important"
    D'oh! Haha. Serves me right for rewriting that final sentence and then not processing it properly in my head. Thanks for the heads-up! I've passed that on for correction in due course. beer

  • Lewis Kingston 21 May 2018

    adricmarsh said:
    Motorola 68000 went one better in the 1990s when Sega ...
    Now there's a far more entertaining application! cool

  • Turbobanana 21 May 2018

    Lewis Kingston said:
    Turbobanana said:
    "that all-important remaining range function is once again becoming increasingly important"
    D'oh! Haha. Serves me right for rewriting that final sentence and then not processing it properly in my head. Thanks for the heads-up! I've passed that on for correction in due course. beer
    In all seriousness Lewis, it's an interesting article and I wasn't aware that the technology had been around for so long. It's also interesting that a cheap, eBay OBD II adaptor and a Bluetooth-enabled smartphone can provide so much more real-time information nowadays.

    The march of innovation - it's important. Sorry...

View all comments in the forums Make a comment