The basic layout of vehicles on the road (in North America, anyhow) is amazingly homogenous. Think about it: there are cars with four wheels, motorcycles with two, and trucks with anywhere from four to twenty-plus wheels (in two varieties – attached and detached cabs).

The last time I saw a three-wheeled T-Rex, it looked so outlandishly exotic, that a crowd gathered around it (the owner had parked it on the sidewalk outside a store). You don’t usually see that even with exotic Italian supercars.

There’s actually a lot of experimentation with wheel plans (i.e. the vehicle equivalent of room plans in a home), but we don’t see it much on a day-to-day basis.

A number of examples that I’ve found were pretty cool (if largely impractical), so I’ll include them here for your amusement:

• Dicycles – yes, that’s right; a bicycle has the wheels arranged front and back, while a dicycle has them side by side; the most famous example being the Segway – an amusing but impractical example can be found here. In theory though, there’s no reason why a larger Segway-type vehicle with a cabin couldn’t work.
• Trikes – like the T-Rex and the Zap Alias.
• An old-fashioned five-wheeled car.
• Larger numbers of wheels – like these or this (awesome!) or this.
• Half-tracked vehicles and other non-wheel-based plans (okay, I don’t really think we’re going to see hovercraft on the roads any time soon, but it bears mentioning).

The reason that I mention these occasionally bizarre examples above has to do with VW.

VW has been very much in the news in the past couple of years for its platform-based approach to building vehicles. You can see the two primary examples here and here. Not all of their cars are based on those two platforms, but they’re heading in that general direction. VW’s approach is powering them to market leading profitability, and many other manufacturers are considering similar standardization.

Here’s the thing though – in simplifying the manufacturing process, they may be creating a lock-in issue for the future. I’ve written about the danger of lock-in before; it occurs when technical decisions made in the past make it difficult to make changes in the future, with all of the consequent results.

VW’s platforms are extremely flexible – they can add or reduce length and make many other changes while remaining within specifications. In theory, they can allow for construction of anything from an ultra-mini up to an SUV. There are some obvious things that they can’t do though – engine placement has to be the same (so no wheel hub motor city cars), and obviously the vehicles all have to have four wheels.

The reason this may be important is because it is very difficult to tell in advance what will work in the auto industry. Few people predicted the success of minivans, SUVs, crossovers, or oddball one-off hits like the PT Cruiser. There’s a lot of experimentation that goes on in the background, with some hits and also some costly flops.

What VW is doing is smart, in the sense that they’re limiting themselves to a subset of vehicles that they can build more cheaply and with better quality than many other manufacturers. However, the resulting higher cost of experimentation may result in a lack of desire to innovate outside of that box. If consumer tastes change rapidly in a direction that is difficult to implement with their platform, they may consequently have a steep curve to catch up. This isn’t something that is likely in the near future, but it may be a problem five or ten years down the road.