Tesla Autopilot No Longer Breaks Speed Limit

John Lister's picture

Tesla's automatic car steering tool will now restrict the car to the local speed limit on most roads. Users had previously been able to set the system to run up to five miles over the limit.

The changes are to a feature which has the full title of Autopilot Traffic-Aware Cruise Control. It not only controls the car's speed as with normal cruise control, but automatically adjusts to keep a safe distance from surrounding vehicles and steers the car to keep in the lane. (Source: electrek.co)

Freeways an Exception to No-Speeding Policy

Once the latest update takes effect, the feature will adhere strictly to the speed limit on most roads. The only exception will be on freeways where there's a physical barrier between lanes running in opposite directions, meaning virtually no risk of hitting oncoming traffic. Here the software will still let the driver set limits of up to 90 miles per hour regardless of the legal speed limit. (Source: digitaltrends.com)

The news has fueled an ongoing debate about safety, practicality and the law. One argument goes that keeping automatic technologies within speed limits avoids encouraging or enabling dangerously fast (and illegal) driving. A counter argument goes that sometimes it safer to exceed the speed limit in order to keep up with the flow of traffic and that automated systems can't make skilled judgments about whether and when to do this.

Of course, there's nothing to stop drivers deciding to exceed the speed limit in such vehicles: they simply need to switch off the Autopilot feature and drive as normal.

Fatal Crash Sparked Rethink

The change is the latest in a series of tweaks Tesla has made to boost safety, prompted in part by a fatal crash involving a driver using the Autopilot technology in May. One was to put more emphasis on radar, rather than cameras when detecting other vehicles.

Another change was to deter drivers relying on the fact that it's physically possible to "drive" completely hands-free using the Autopilot. Drivers now get a visual and audible warning if they take their hands off the wheel for more than a minute while driving faster than 45 miles an hour. Ignoring three of these warnings inside an hour means the feature switches off until after the next time the car is parked.

What's Your Opinion?

Do you agree with Tesla's decision to stop Autopilot working above the speed limit? Is it a sensible balance to "enforce" the speed limit for Autopilot on ordinary roads while giving drivers leeway when on a freeway? Do you think the issue of which is safer, human or automated drivers, has a different answer at very fast speeds?

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Dennis Faas's picture

This may sound counter intuitive - but driving the speed limit often leads to crashes.

Based on my own experience, there is a highway close to where I live which connects the USA to Canada on the west side of Windsor, Ontario. That highway is known as Highway #3, and it stretches outside of Windsor and into surrounding counties. One particular stretch is near Essex, Ontario, which was notorious for fatal crashes for years (before they upgraded it) because it would reduce from 2 lanes down to 1 lane.

Because many people live out in the county, they would commute long distances to work. Truckers driving on Highway #3 (both ways) would drive the speed limit, however, many times commuters would want to drive faster in order to get to work on time. On a 2 lane highway this isn't much of an issue - you simply pass the truck in the faster lane. However, when Highway #3 got down to 1 lane, many times commuters would attempt to pass the truck only to find out they did not have enough time to complete the pass, then end up in a fatal crash.

Based on that, driving the speed limit - which often results in being stuck behind someone that is driving slower than the rest of the traffic on the road - can often lead to hastened thinking and bad decisions, hence more accidents on the road. I think they should at least make it 5 over the limit. I doubt any cops are going to pull anyone over for driving that much over the limit, and 5-10 km/h (and possibly mp/h) tends to be the sweet spot between driving too slow and keeping up with traffic.

gbruce40_3626's picture

On the Ontario 400 roads the speed limit is 100kph. Most cars drive at an average of 120kph other than trucks, which in Ontario, must have a speed limiter set to 105kph. Many trucks from the USA do not have those speed limiters and often go over 105kph.

To say that we should increase the speed limit to 120kph, as that is what most are doing, just means that cars will drive at 140kph. You can never solve the problem of drivers doing the speed limit and drivers exceeding it. It is the drivers going well over the speed limit that causes the accidents, together with the drivers under the influence and drivers who are on there cell phones, plus the souped up cars who's drivers are trying to prove something.

The only way to go is set a speed limit and strongly enforce it. The problem is that we do not have enough police or and it would be prohibitively expensive to police.

Try driving in any big city like Toronto, it is not pleasant and there are fatal accidents everyday. Self drive cars are just an additional hazard added to the mix.

blueboxer2's picture

In Ontario, the primary speed limit is "safe and appropriate to conditions". Signs indicate the limits of "safe" under normal conditions as determined by politicians catering to a populace of voters who know nothing about serious traffic safety issues. GBruce mentions some of the more popular mythologies.

Serious researchers using scientific methodologies have discovered that for some reason if the general traffic using a given stretch is timed and recorded, the best safety results come when the limit is set to the 85th percentile speed of the sample. Only the most enlightened jurisdictions set their speed limits this way.

In all other cases the numbers on the signs are too low or occasionally too high. A skilled and knowledgeable driver will generally and where possible do the safest speed. And where his experienced and expert judgment is being exercised, some self-righteous automaton should not be allowed to overrule him. Running at a knowledgeably judged speed under cruise control will likely produce the safest passage, and what the driver chooses should rule and overrule.

petershaw's picture

In the UK Government revenue from speed cameras is enormous. I can't help wondering if there might be political opposition to having automated speed limiting of cars that lowers this level of income.