• trash80@lemmy.dbzer0.com
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    1 year ago

    This mechanism does not allow angular deflection between the motor and hub, as it’s shown, without a CV joint. Lateral displacement, yes, but not angular - as in it can’t steer.

    The axis of the motor doesn’t need to be parallel to the axis of the wheel.

    If the axis of the motor is vertical, you could use a ring and pinion gear to transfer the torque to the driveshaft running out to the wheel, and have the steering wheels pivot around the axis of the motor.

    • XeroxCool@lemmy.world
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      1 year ago

      The steering wheels’ hubs rotate in two directions. The steering action rotates through a vertical axis while the typical suspension rotates in a front-to-back axis pinned approximately through the other side of the car. So unless they abandoned common suspension design to let tires lean in turns more than a reasonable amount, there needs to be an allowance for angular deflection. A pinion gear arrangement sounds like it would take up a lot of the space they’re trying to save but still not solve the multi-axis problem found at all 4 wheels. I’m trying to not take their video so literally but it’s not like it’s a dealership rep spouting incomplete info here

    • BearOfaTime@lemm.ee
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      1 year ago

      But you need a CV or Universal on that drive shaft to accommodate suspension travel (or steering if needed on that wheel).

      • trash80@lemmy.dbzer0.com
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        1 year ago

        What for? The axis of the driveshaft would always be parallel to the axis of the wheel and perpendicular to the axis of the motor.

        Look at this hand drill:

        The hand crank is the electric motor. If you rotate the drill about the hand crank axis, you don’t change any angles between the drivetrain components and don’t need CV or universal joints

        • BearOfaTime@lemm.ee
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          1 year ago

          Suspension movement still requires flex in the shaft. There’s no way around it unless the engine moves with the suspension

          • trash80@lemmy.dbzer0.com
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            1 year ago

            There’s no way around it unless the engine moves with the suspension

            Yes, there is.

            Take a conventional front engine, rear wheel drive drivetrain. Rotate the drive train 90 degrees about the rear axle, as if the automobile has its nose in the air, with the driveshaft oriented vertically.

            You can steer the vehicle by rotating the entire axle around the axis of the driveshaft, though it isn’t perfect or space efficient, it would require no universal or CV joints. It would behave sort of like a vehicle with an articulated frame.

            The axle could be fixed vertically with uni wheels at the ends of the halfshafts allowing the wheels to travel vertically independent from the axle.

            Do you understand so far?

        • snooggums@kbin.social
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          1 year ago

          Now imagine there is a handle sticking out of the crankshaft that needs to rotate around the shaft with the hand crank as it gets turned. That is the motor.

          The video never showed the motor moving along with wheels turning, only the up and down part. In fact, when they showed space savings they showed the motors as stationary with no clear way to turn.

          • trash80@lemmy.dbzer0.com
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            1 year ago

            Now imagine there is a handle sticking out of the crankshaft that needs to rotate around the shaft with the hand crank as it gets turned. That is the motor.

            What are you referring to as the crankshaft?

    • dubble_deee@lemmy.world
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      1 year ago

      Unrelated comment, but holy shit I am a huge fan of the M8. So wild to see you on Lemmy, and this comment section is exactly what I’m here for.