• KillingTimeItself
    link
    fedilink
    English
    0
    edit-2
    8 months ago

    tesla makes interesting cars, but i wait for the day they stop producing drive units, and start producing wheel drives. Hub motors are definitely the objectively correct solution when it comes to EVs IMO. There are so many more things you can do, and so many more options you’re opened up to.

    oh and they stop being proprietary garbage, perhaps one day we will get opentesla firmware, as a hack.

    • @evergreen
      link
      68 months ago

      Nobody uses hub motors on production EVs yet as far as I’m aware due to the much higher unsprung mass this creates. That is to say it is a bunch more weight flopping around on the opposite end of the suspension from the frame. This leads to handling, ride quality and reliability issues. Rivian does at least use a 4 motor system though.

      • KillingTimeItself
        link
        fedilink
        English
        18 months ago

        yeah that’s definitely a potential problem. Even then drive units aren’t particularly helpful. They do isolate half the drive train on AWD vehicles, but that’s about it.

      • KillingTimeItself
        link
        fedilink
        English
        18 months ago

        im not super familiar with it, but having skimmed the one article im willing to read about it, it seems interesting, im not entirely sure what it intends to do, but that’s a fault of the article for not fucking explaining it lol.

        If you have a very concise technical TL;DR that would be very appreciated. I genuinely cannot read the majority of content on the web because it has nothing of actual value to me. Reading documentation that actually explains things and technical papers has ruined me.

        Shits all marketing speak primarily these days, i don’t care, tell me what it is, and show me a demonstration or a diagram. Nothing more needs to be said IMO.

          • KillingTimeItself
            link
            fedilink
            English
            18 months ago

            ok, to be clear, im not educated in this field, but im a hyper nerd in this kind of shit, so i feel like i have some pre-existing understanding here.

            notably, this is a take on planetary gear sets, which are notoriously, gear sets. They’re fine. There’s nothing weird about them, except for the fact that they reduce on an axial measure, which is really weird but super useful for things like wind turbines.

            Functionally, it’s pretty clever, the vertical motion is obviously useful, the side to side deflection is also going to be pretty important because nothing is perfectly rigid. I’m curious to know how maintenance is going to go, it might be a bit of a nightmare. I assume it’s not that bad though, probably easier than a transmission. Which we no longer have in an EV.

            If it can be made in volume, reliably, and for a reasonable price, this is definitely the future. Yeah, i mean really my only concern would be maintaining it. Which im guessing it’s just an enclosed gearset in an oil bath, so probably pretty trivial. Just replace the oil every so often (or as per every modern vehicle, throw it out and replace every 100,000 miles or so)

            Curious how they’re going to seal the enclosure to the environments though, probably a boot, im sure that’s going to be equally as problematic as every CV boot ever has always been so nothing new there really.

            • @[email protected]
              link
              fedilink
              08 months ago

              Thanks for the insight! My uninformed view was that from a moving parts perspective it was a lot fewer than a transmission and traditional drivetrain, so it seemed like there would be fewer points of failure and less complicated maintenance. It also seemed easy to produce, even with tight tolerances it’s pretty mechanically simple.

              It was hard for me to see if it was just marketing hype though. It’s interesting that wind turbines use planetary gear sets! I never thought about it before beyond “wind spin blade= electricity.”

              • KillingTimeItself
                link
                fedilink
                English
                18 months ago

                oh yeah no, it’s vastly simpler than an ICE engine,a clutch ,a transmission, a transfer case, the drivetrain, the differentials, and then the CV joints to the wheels.

                It’s certainly going to be easier to access than that whole drivetrain, that’s for sure. And if you lose the proverbial first gear here, you still have 1-3 other motors taking up the slack.

                wind turbines are pretty interesting, it makes sense that they use planetary sets though. It simplifies construction, and minimizes the surface area facing the wind (more power generation) There’s a lot of weird things you can do with planetary sets. The two speed transmission in a drill for example? That’s a planetary set, where the speed setting just locks a ring gear set to it’s planets and sun gear. Thus nullifying a stage of reduction, I.E. giving you go fast speed. And then unlocking it gives you another set of reduction, I.E. slow speed for more torque.

                like i said, if they can tackle the fundamentals there, which seem very possible to me. This is definitely how this stuff is going to work in the future.