Tesla is no longer making a right-hand drive version of its Model S and Model X electric vehicles. The decision means that customers in countries that drive on the other side of the road, like the UK, have had orders canceled, and potential buyers are being told to buy a different model, a car from inventory, or try a left-hand drive version.
About 30 percent of the world’s nations drive on the left side of the road, known confusingly as right-hand drive, as the driver’s seat is on the right side of the car. The UK is probably the best-known right-hand drive country, along with most of its former colonies. While most of these are small countries, the list also includes highly populous countries like Japan, Indonesia, and India.
Ars was contacted by a reader from New Zealand who ordered a right-hand drive Model X SUV almost three years ago because Tesla reached out to him yesterday to cancel his order:
Due to recent changes to the vehicle program, Model X will not be available in Right Hand Drive. Unfortunately this means your order is unable to be fulfilled and will be cancelled. You will receive a full refund for any payments made. We understand that this may be disappointing news to receive and want to apologise for any inconvenience caused.
Tesla offered our reader a NZD$3,200 credit toward a Model 3 or Model Y, although only if they purchase that new Tesla before October.
Higher levels do exist in aerospace (DAL-A) and industry (SIL-4), eg. an "if this thing fails, the airplane will break up in flight" or "if this thing fails, toxic gas will kill everyone within a mile" scenario.
Certifying mechanical systems to the equivalent of ASIL D (which is an electronics standard, not a mechanical one) is complex and expensive. Certifying electronic ones to ASIL D is very complex and very expensive. Add software to the mix and you're into horrifically complex and obscenely expensive.
Essentially, to prove a system to ASIL D, you need to enumerate every possible way in which any aspect of the thing can fail. For every one of those scenarios, you need to work down the entire fault tree to determine the likely consequences. Then you need to calculate the individual probabilities for every one of those failures, and the probabilities for multiple-failure scenarios that compound to make a bigger failure, and so on.
Then, when (not if) your resulting number shows the system to be too risky, you need to go back and redesign the whole thing to add redundancy, allow for "try-catch" scenarios in both hardware and software for every possible failure, and recalculate all the probabilities.
Rinse and repeat until you've proven that your design is safe enough to use. It's certainly doable, but it's tedious and very expensive.
Hence Infiniti's spring-loaded clutches. When the SBW craps its pants, it doesn't have to self-repair and heal its failure within milliseconds; it can just say "oops" and release a relay and then everything falls back to the way it worked in 1947 with shafts and U-joints. Most potential buyers hated the SBW anyway, so all that effort was wasted.
Proving a totally new system to ASIL D without such mechanical fail-safes is a very expensive engineering effort, and a company will only undertake such a thing if it sees the potential for very real revenue and profit improvements.