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Ask HN: What would a car engine look like that was robot serviceable?

29 points by a3n ↗ HN
An ICE is a metal block containing a shaft and attached pistons, with various "peripherals."

What would an engine and its immediate surroundings look like to be totally robot serviceable, including diagnostics, adjustment, peripheral replacement, and total engine replacement.

Why don't we have that?

18 comments

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android2222
Perhaps wide and flatter to allow for easy access, and up higher in the engine bay? As to “why don’t we have that” - I think that by doing that you’d throw off the center of gravity, because an engine is made out of heavy strong metal to withstand the pressures it generates.
axaxs
Probably a lot like early cars, say 50s or prior.

The problem is that as safety and fuel regulations increase, design gets more clever and space gets tight.

Spooky23
Different companies have different approaches. My Honda is pretty easy to work on. I drove a 1993 Pontiac Bonneville in college that was a nightmare to work on as the tolerances were designed for robotic assembly. (And nothing else)
m463
So cars ARE designed for robots. Really.

Thing is, they're designed for assembly.

They're made on an assembly line, put together layer by layer with the inner parts going in first and outer parts later.

I remember reading about one assembly line where it was designed so the engine came into the car from underneath.

For example, I had to get in the trunk of my car once to replace a tail light. I had to remove a panel, and it had a fastener that looked like a christmas tree. It was really hard to get the panel off, but when I was done, just position it and push and it goes click click right into place.

So I think they're optimizing for a car that assembles quickly and cheaply, and is reliable enough so it doesn't have to come apart.

"reliable enough" might change with electric cars though, because it's looking like they will have a fraction of the moving parts and may last 5x or more what an ICE car will last.

If YOU will take them apart, get an old car. They less reliable so they were designed for people to work on them. Get one of those. Better yet, an old pre-electronics tractor. They were designed for farmers to work on with a small assortment of parts.

Or get a Humvee. The first one, the H1. They were designed to be taken apart and fixed in the field, with a small assortment of tools and lives depended on this capability.

whatever1
“... "reliable enough" might change with electric cars though, because it's looking like they will have a fraction of the moving parts and may last 5x or more what an ICE car will last.”

Just no.

Electric cars have rotors, brake pads, compressors, heat pumps, fans, water pumps all of the nice stuff that typically drive you to your ICE mechanic.

On top of that they have a battery that degrades from day 1 of the purchase and data from the Teslas don’t support your opinion that they can hold 5*12=60 years. I did not even mention their reliance on electronics, that fail as bad as they fail on ICE cars (sensors, microcontrollers, screens, capacitors, cable looms etc).

Pitch EVs for something else, but not for their reliability.

petertodd
Re: the battery lifetime, I think you're mistaking lifetime for reliability. You can have something with a moderate or even short lifetime that still has high reliability during that lifetime. Lithium batteries certainly do degrade over time - even in storage they degrade. But during their expected lifetime they are very reliable, and you can expect them to need no maintenance at all. The same goes for the power electronics and electric motors: if properly designed and operated within their specs they can last indefinitely as there are hardly any wear mechanisms.

Of course, Tesla has had a spotty history in actually achieving that, with the flash chips being a good example. At least when I was doing electronics a few years ago, I ran into quite a few automotive grade microcontrollers and flash chips advertising expected lifetimes of 25 or even 100 years(1) if used correctly with sufficient wear levelling. In that case, Tesla obviously didn't.

1) http://ww1.microchip.com/downloads/en/appnotes/91072a.pdf 40 years retention over full temperature range, 100 years at 25degC.

closeparen
The “unreliable” luxury brands are reputed to be just fine during their lease/warranty periods. If this defense works for Tesla it has to work across the board.
m463
You know what, I guess my thinking and writing was not clear.

I was thinking - with an EV you don't have to DO anything.

I had a leaf and was thinking I should take it in for maintenance, but looking at the manual there was coolant, but you changed it at 125k or something. The brakes wore very little. Tires maybe. maybe brake fluid since it's hygroscopic.

There was small stuff - windshield wipers and fluid. there was a cabin air filter. wash it.

As far as reliability, it worked fine daily.

oskarpearson
Having read that EVs are more reliable in the past, I was surprised at your response.

https://www.quora.com/Are-electric-cars-more-reliable/answer... seems quite comprehensive.

Overall, they should be more reliable, though it’s early days and there are teething problems. At the moment they are at least at a similar level to Petrol engines.

https://www.fleetnews.co.uk/news/latest-fleet-news/2019/09/0... supports this.

ICE cars contain a chunk of metal that is guaranteed to wear out from day 1 of the purchase due to friction and combustion effects. So overall not that different.

Spooky23
That’s really not true. Maintained gas engines average around 200k miles without overhaul, diesel 1.5M. The typical car’s life is governed by failure of suspension, braking and other components.

Tesla tends to dominate the electric conversation. Their quality is inconsistent and minor problems are major because they really suck when it comes to parts and controlling who can repair. (Ie a 48 hour repair in a Honda may be 48 days on a Tesla)

My former employer operated a fleet of Toyota Prius, which are more complex and had an expected service life of 190,000 miles.

Spooky23
People tend to hand wave about reliability, but the reality is that emissions standards drove ICE car reliability to a very high level. The reasons that cars are scrapped usually boil down to corrosion and stress related failures between 200-300k miles.

Electric cars eliminate belt failures. Everything else is driven by reliability engineering. 95% of Teslas or Chevy Bolts will be scrapped within 10 years or 250k miles, just like anything else.

sgt
Anything before 2003 BMW would be a reasonable choice too. E39 5-series and before. Preferably before that even, like E34 because the E39 had some bizarre design decisions like putting the ABS controller too close to the engine so that it would die. Getting a used one installed is fairly easy, except for the re-coding part which requires a laptop running BMW diagnostics software (readily available on TPB).
fuzzfactor
>What would a car engine look like

I know it would have to look way different.

>Thing is, they're designed for assembly.

Instead design for disassembly.

Seems to me the first single milestone would be to design for simple rapid robot removal of the whole engine.

No further disassembly required.

Even if replacement with a new freshly-tested engine needed significant manual intervention, it would still be a huge step. Especially if it was easy enough for a robot to remove to begin with.

Later upgrade the auto-removing robot to do the auto-diagnostics/auto-final-validation-before-deployment process.

Even if actual repairs still need to be done manually.

Reach this milestone without anyone ever wanting to step back, then maybe consider having the robot start removing your spark plugs rather than using an established expert.

quickthrower2
Good question. Although looking forward EVs are the more obvious choice and I’d imagine would naturally be easier to service and need fewer services.
phendrenad2
Robots are still in the dark ages. Doing anything with a robot arm requires massive amounts of human intervention to get the motion just right. Custom grippers have to be made for every part.

Anecdotally: Interviewed with a robotics company that claimed to be doing lots of AI/CV/ML to direct robot arms, but in the interview they admitted that they weren't able to use the ML in practice and had a bunch of traditional robot arm programming staff just to pay the bills. It seemed like they had inserted themselves as middlemen into another businesses process with the false promise of AI, like IBM Watson.

a3n
I imagine a regularish block, with all "peripherals" being blockish, and mounted into recesses on the main block. The functional interface would be at the block-peripheral meeting point.

That might make the robotic design task easier.

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2rsf
Watching my car getting fixed I think that part of the problem is that parts deteriorate over time making the robot's life very unpredictable.

More than once a hammer and chisel were used to take a part or put together parts, and in other places they needed to improvise or file a part so it fits better.