Live data from Hacker News

Running Tesla Model 3's computer on my desk using parts from crashed cars

bugs.xdavidhu.me

151–160 of 356 posts

Re: Running Tesla Model 3's computer on my desk using parts from crashed cars

#151
post #109

Earlier quoted context omitted.

Yeah, max CV charging voltage is ~14V, max charging C rate is ~0.2C, open circuit voltage at 100% is that 13.x range. And lead acids like to stay at 100% unlike Li-ion which likes 50% +/-30%, so "12V" ICE cars just use a bus voltage of 13-14V and wire the battery there. At any given moment, the car's "12V" bus voltage MUST be above 13.x and below 14.4(absolute max). It's a bit perplexing that those lead acid systems…

The nominal range for automotive systems is 10-16v. If you are designing anything for automotive use that doesn’t work reliably in that range, you are manufacturing problems for people.

This. Most cars nowadays come with the so-called "smart" alternators that vary voltage wildly depending on the current driving conditions.

One minute you might be accelerating and the onboard voltage drops as the battery supplies most of electricity. Then, as you reach the crest of a hill and start engine-braking, the car frantically tries to convert all the available kinetic energy to electricity, raising the onboard voltage to quickly charge the battery.

Re: Running Tesla Model 3's computer on my desk using parts from crashed cars

#152
post #59
post #50

Congrats, OP has recreated a test/development bench, the bane of developers working on automotive software development all around the world. They're so close to being a real vehicle that you think you'll be able to get a lot of work done, but they're not, so you don't.

Honestly I love it. Few things develop a more fun camaraderie than a bringup bootcamp with two precious/priceless new samples on a large conference table, and everyone being very careful to keep cups/mugs very far away. And a soldering robot with a specialist a few rooms away to beam down the latest errata into physical form, at times. Tracy Kidder just died, and Soul of a New Machine was a favorite of my formative y…

Haha, don't forget your wristbands.

Re: Running Tesla Model 3's computer on my desk using parts from crashed cars

#153
post #99

From the article > Tesla offers a “Root access program” on their bug bounty program. Researchers who find at least one valid “rooting” vulnerability will receive a permanent SSH certificate for their own car, allowing them to log in as root and continue their research further. Pretty interesting. Sounds like Apple's Security Research Device Program[0], where you're loaned a rooted iPhone, but with a clear qualificati…

> Researchers who find at least one valid “rooting” vulnerability will receive a permanent SSH certificate for their own car It feels like this is something you should get by being owner of the car, and not have to do free speculative research for the manufacturer to get it.

As much as I tend to agree philosophically, could it not result in people making changes that endanger other road users?

Re: Running Tesla Model 3's computer on my desk using parts from crashed cars

#154
post #99

From the article > Tesla offers a “Root access program” on their bug bounty program. Researchers who find at least one valid “rooting” vulnerability will receive a permanent SSH certificate for their own car, allowing them to log in as root and continue their research further. Pretty interesting. Sounds like Apple's Security Research Device Program[0], where you're loaned a rooted iPhone, but with a clear qualificati…

> Researchers who find at least one valid “rooting” vulnerability will receive a permanent SSH certificate for their own car It feels like this is something you should get by being owner of the car, and not have to do free speculative research for the manufacturer to get it.

You can feel that way, but plenty of car configuration has always been locked away and walled off, and manufacturers make a tidy profit selling software licenses to dealers and mechanics to perform basic diagnostics. Proprietary software is big business what can you do.

Re: Running Tesla Model 3's computer on my desk using parts from crashed cars

#155

Earlier quoted context omitted.

> Researchers who find at least one valid “rooting” vulnerability will receive a permanent SSH certificate for their own car It feels like this is something you should get by being owner of the car, and not have to do free speculative research for the manufacturer to get it.

As much as I tend to agree philosophically, could it not result in people making changes that endanger other road users?

I don’t think that’s the reason, seeing as a car is already endangering everyone around it by existing. More likely about keeping the tooling to diagnose issues proprietary and expensive.

Re: Running Tesla Model 3's computer on my desk using parts from crashed cars

#156
post #99

From the article > Tesla offers a “Root access program” on their bug bounty program. Researchers who find at least one valid “rooting” vulnerability will receive a permanent SSH certificate for their own car, allowing them to log in as root and continue their research further. Pretty interesting. Sounds like Apple's Security Research Device Program[0], where you're loaned a rooted iPhone, but with a clear qualificati…

> Researchers who find at least one valid “rooting” vulnerability will receive a permanent SSH certificate for their own car It feels like this is something you should get by being owner of the car, and not have to do free speculative research for the manufacturer to get it.

You can translate that to corresponding car-purchases, i.e. vote with your wallet.

Re: Running Tesla Model 3's computer on my desk using parts from crashed cars

#157
post #99

From the article > Tesla offers a “Root access program” on their bug bounty program. Researchers who find at least one valid “rooting” vulnerability will receive a permanent SSH certificate for their own car, allowing them to log in as root and continue their research further. Pretty interesting. Sounds like Apple's Security Research Device Program[0], where you're loaned a rooted iPhone, but with a clear qualificati…

> Researchers who find at least one valid “rooting” vulnerability will receive a permanent SSH certificate for their own car It feels like this is something you should get by being owner of the car, and not have to do free speculative research for the manufacturer to get it.

[dead]

Re: Running Tesla Model 3's computer on my desk using parts from crashed cars

#159
post #99

From the article > Tesla offers a “Root access program” on their bug bounty program. Researchers who find at least one valid “rooting” vulnerability will receive a permanent SSH certificate for their own car, allowing them to log in as root and continue their research further. Pretty interesting. Sounds like Apple's Security Research Device Program[0], where you're loaned a rooted iPhone, but with a clear qualificati…

That’s quite a weak confidence in their own platform security if finding a root level vulnerability is not one-off event, but it’s a program expected to have multiple people routinely finding those.

Well it's a selection bias.

If an athlete breaks a world record, they're likely to do it again. Even though it's incredibly hard to break a world record.

Re: Running Tesla Model 3's computer on my desk using parts from crashed cars

#160

You can run QtCar (the Qt-based app that Tesla uses for their UIs) on QEMU - if you have the firmware. https://x.com/i/status/1722717318009041104 DM me if interested

Just put it online somewhere

It's on GitHub, but I want to avoid Tesla DMCA-ing it
Post reply on HN