# How does neutral buoyancy work?

I’ve seen some vex forum discussions on neutral buoyancy, but they’ve always been for bar lifts to reduce strain on the motor. I recently saw that 606X had rubber bands around their motors, and I think it has something to do with neutral buoyancy, like maybe securing the motors to the metal its being connected to? What even is neutral buoyancy and how can I apply it to motors?

This is the video I found with rubber bands around the drivetrain motors:
606X Spin Up | Drivetrain + Catapult Explanation - YouTube (go to 0:47 and 1:33)

Those are quickswap bands.
Basically, the screws holding the motor cap (the part you remove if you want to change the cartridge) are removed completely and the rest of the motor is held on the cap with a combination of zipties and rubber bands. This makes it so that if the motors overheat, they are very easy to remove and switch out with cool motors.
Has nothing to do with rubber banding on a bar lift (although neutral buoyancy is a cool term for that, I haven’t heard that before).

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Neutral buoyancy is adding rubber bands from somewhere above the lift to the end of the lift to make it easier to lift up. You could also put the rubber bands around sections of the lift that get closer together when it is higher up.

Buoyancy is a force you get when something displaces a liquid. If you hold a ball under water it displaces and lifts the water up (water level rises). The buoyant force is equal to the weight of the displaced fluid. It is what keeps boats afloat. If something is completely submerged and the weight equals the buoyant force, then we call it neutral buoyancy. Any small force will cause it to go up or down. (like a submarine)

Adding rubber bands to an arm mechanism is called passive assistance. The force applied by the rubber bands helps to counter the force of gravity on the arm. But adjusting the rubber bands you can get something similar to neutral Buoyancy. The motors don’t have to support the weight of the arm and the arm can either lift more weight or move quickly. However, we shouldn’t call This neutral buoyancy as the force applied by the rubber bands is not a buoyant force. I suppose a better name might be passive equilibrium.

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