I agree. When I first started reading this thread, I thought that some reporter made up the “autopilot” name. Having read Car & Driver, I already this wasn’t a true autopilot system, but rather a set of features that assist drivers. Tesla should have known better than choose the name autopilot, as people would really think they didn’t need to do anything.
The four cars C&D tested contained features named:
BMW 750i xDrive: Driver Assistance Plus, Active Driving Assistant Plus
Infiniti Q50S: Intelligent Cruise Control, Predictive Forward Collision Warning, Forward Emergency Braking, Lane Departure
Mercedes-Benz S65 AMG: Distronic Plus with Steering Assist, Adaptive Brake Technology, Active Lane-Keeping Assist
Tesla Model S P85D: Autopilot, Autosteer, Auto Lane Change, Autopark, Traffic-Aware Cruise Control
That was exactly their intent. If there is a flaw is in the name, it’s that they did not realize the public massively overestimates what a real autopilot can do.
An actual autopilot, like for planes, is not “press a button and it flies you to your destination”. What it does is fly the heading and speed you give it. It may have basic collision avoidance systems, but only under certain conditions. At all times the pilot in command is still flying the plane–what the autopilot does is reduce the pilot workload so she can pay more attention to other things and to reduce fatigue. If anything unusual happens the pilot must step in.
That is what’s going on here. When Tesla has actual self-driving, they’ll call it that.
That was my first thought too. If you don’t already know what “cruise control” is, doesn’t that sound like it should be doing a lot more than just maintaining speed?
The idiot who died watching TV while operating a car deserves a nomination for the Darwinian Award. However, 29 lane deviations in 50 miles and “semi-autonomous” certainly deserve some kind of award for car options.
Note that in this latest case, Tesla said that autopilot was not being used. From their statement, “We can confirm from the car’s logs that Autopilot was not engaged at any time during the drive cycle and that, consistent with the damage that was observed after the vehicle struck the tree, the vehicle was being driven at more than 155 km/h.”
that’s a real plus. Not sure what to make of the fire.
smash an ICE car and it’s a fireball. Bring marshmallows. Otherwise smaller fires are easily dealt with with an extinguisher. Smash an electric car and what needs to be done differently by the fire department?
Most electrics have a cable in a prominent spot that can be cut by the FD. On the Model S, there is a loop at the base of the windshield, on the passenger side (see page 13). This disconnects the battery and generally safes the vehicle.
The lithium battery can only discharge at a certain maximum rate, so even though it is relatively hi DC voltage (375 V) the amperage is such that it isn’t going to arc dramatically. As Dr. Strangelove notes, the vehicle can be inerted by cutting the main power feed. The battery, absent of power distribution or leads isn’t going to electrocute anyone, although if one or more cells are shorting internally without a dissipative element it can undergo thermal overload.
The lithium-ion batteries can burn quite energetically if ruptured, and once enough adjacent cells start thermal overload it will consume the entire pack. Lithium metal batteries (lithium-iron, lithium copper oxide, lithium manganese, et ectera) can react violently to a water flame suppressant and should be treated with Class D fire extinguishers, but the lithium polymer batteries in the Tesla have relatively little lithium, and what there is bound up (intercalcated) in the polymer matrix, so Class ABC or even plain freshwater can be used. However, once ignited the energy density is such that fire crews are generally advised to let it burn out and only suppress secondary fires.
After a handful of initial incidents, Tesla reinforced the underside of the Model S to protect against road debris penetration and instituted. more robust battery management system that shunts around cells that show abnormal voltage performance, but like any dense energy storage medium, the batteries do have a potential for energetic release. As noted, the drverdid not have the Autopilot system engaged (sensationalist rhetoric of the linked story aside) and would not,have been using it appropriately if he had.
That’s fine for minor accidents but this wasn’t a fender bender. You smash up a battery pack and it catches fire it’s a twisted mass of interconnected batteries.
Do you throw water on it or will fire departments have to adapt to a different method of fire suppression.
The linked instruction is an instruction manual for First Responders.
IIRC, they say to use lots of water - not to only extinguish current fire, but to cool the battery pack to keep it form re-igniting.
It seems the rule is “Take your time and bring lots of protection, and maybe your own air to breath”.
Yeah–it basically says to use large amounts of water or none at all. Letting it burn is an option if you can protect against toxic vapors. Otherwise, use large amounts of water to cool the battery. They don’t say exactly what happens if you only use small amounts of water, but I can imagine various bad things happening if the water pools in a way that it doesn’t significantly cool the battery, but can still flash to steam quickly when it drains in a certain way.
An electrochemical battery is not like a capacitor and doesn’t storage energy in the form of fully developed electrical charge; it has to undergo an electrochemical transfer from cathode to anode to generate current and develop a voltage potential. It cannot just suddenly develop and generate electrical charge. A set of cells functioning in parallel can develop a potentially hazardous amount of voltage (as previously mentioned, the battery of the Tesla Model S develops a 375 V potential) hence the need to deactivate the battery before doing something intrustive to the car but cells that are ruptured or damaged generally develop little or no voltage and are burning and caustic hazard rather than an electrical one.
Batteries don’t suddenly develop a charge, they either have a charge or they don’t. If a car is severely damaged then there are banks of batteries with their interconnections ripped apart and exposed. This is an electrical hazard. You can weld metal with a standard car battery.
I’ve never understood the idea that we’re safer putting people who don’t understand the technology and who will suffer no consequence if it fails in charge of telling the people who do understand the technology and will suffer consequences if it fails how to implement that technology.
You don’t seem to understand how electrochemical batteries work. Cells cannot suddenly develop the large voltage potentials that you envision, and rupturing a cell isn’t going to cause it to discharge lightning bolts. It may start combusting, venting noxious gas, or spray caustic electrolyte, but it won’t start throwing off bolts of electricity.