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Well, hybrids sometimes get to replace the transmission with EV bits, like Toyota's system. Imagine an engine and exhaust system; now multiply the complexity by
by pkulak 2y ago
Well, hybrids sometimes get to replace the transmission with EV bits, like Toyota's system. Imagine an engine and exhaust system; now multiply the complexity by 100 and you have a modern transmission. Toyota hybrids (and GM/Chrystler/Honda) replace all that with a single planetary gearset, or with Honda, one clutch.
Other systems, think Volvo, pop the EV bits in the back of the car and replace where the drive shaft used to be with batteries. That seems like a decent trade to me as well. Still have a transmission, but at least it's not purely additive.
AND one man's added complexity is another's redundancy. If the charging module goes bad in a hybrid, you can still drive. Or if you run out of gas.
All that said... I still prefer EVs to hybrids. Do one thing, do it well, I say!
- mulmen 2y agoModern transmissions can’t be two orders of magnitude more complicated than a modern ICE. If they are then I need to get into transmission design. An automatic transmission is basically just a series of planetary gears anyway. I would expect the marginal complexity between an ICE transmission and a hybrid transmission to be within a multiple of 2, but closer to parity. They’re both extremely reliable but an EV transmission (gearbox) will be even simpler.
- hnav 2y agoThe thing that mechanically totals modern crap cars (think cheap Nissans and Subarus) is often the CVT. Ford and GM have transmission problems pretty often. GP is totally right that the planetary eCVTs actually make cars way simpler. Look at Ford's (horrendous reputation with small cars) hybrids from the 2010s, lots of them running around with 300k on the clock.
- SmellTheGlove 2y ago> (think cheap Nissans and Subarus) You don't even need to limit it to the lower end models with Subaru. The top trim Outback and Ascent have a CVT these days. If you want an automatic transmission in your WRX, same thing - a CVT. Anyway, you're not wrong.
- mulmen 2y agoA CVT is even simpler than an automatic. They may be less reliable but not necessarily more complicated.
- pkulak 2y agoI dunno, maybe 100x was an exaggeration, but not by much! Take a look at this transmission from 2007. They haven't gotten simpler. Lot's of cars are sporting 10-speeds these days. https://en.wikipedia.org/wiki/Automatic_transmission#/media/File:Automatic_transmission_cut.jpg https://en.wikipedia.org/wiki/Automatic_transmission#/media/...
- mulmen 2y agoThe number of speeds is a function of the number of planetary gearsets. They’re just connected in series. More speeds isn’t more complex, it’s only a larger part count. By the time the transmission is computer controlled and has two speeds it’s as complex as it’s going to be. Modern ICE are also extremely complex. Turbo systems, sensors, air management, heat management, the list goes on. So yeah, a modern transmission is complex but a modern ICE isn’t simple. By comparison they’re very similar in terms of complexity, the ICE possibly being even more complex.
- serf 2y ago>By the time the transmission is computer controlled and has two speeds it’s as complex as it’s going to be. I don't disagree with your posts greater point, but I disagree with this. There is an endless amount of variable complexity in the engineering behind friction materials, actuation styles, the control systems within the computer control, the material selections.. the list goes on. I mean entire branches of metallurgy were more or less founded in the pursuit of finding stronger alloys for gearbox work. entire branches of metrology were developed for the sake of gearbox failure analysis -- there is a lot of complexity. It's stupid to get into a pissing contest between engines and transmissions, they're both astoundingly complex.
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- mulmen 2y agoI don’t buy that transmissions are somehow unique or even exceptional in motivating improvements in design and materials science. The ICE will benefit from the same improvements and has even more opportunities to utilize those improvements.
- robocat 2y agoLook at a workshop maintenance manual to get a rough idea. One car I had, about a third of the book was dedicated to the automatic transmission. Auto transmissions are very complex.
- mulmen 2y agoYes, in a past life I rebuilt automatic transmissions so I am familiar with their complexity. Transmissions are complex but so are a lot of things. Internal combustion engines are more complex than transmissions. Pages in a shop manual are a proxy for the complexity of service, not of the component itself.