Motorizing the 4-Bar Lift

Hello VEX community! My team and I have recently created a 4-bar lift that we have yet to attach motors to. As of now, we have six motors on our robot, and the limit is eight. We only have one to allot to the lift driver, and I’m worried that it won’t be able to drive both sides equally. That is to say, I think that the side with the motor on it will be lifted higher than the other side, and it will be lopsided. I’m also thinking about whether or not it’s worth the trouble to add high-strength axles. Thank you all in advance!

If you make the lift rigid enough, you’ll be fine with 1 motor and ls axles. The amount of bracing you need depends on the torque tho, so play around with it


using rubber bands helps keep the amount of force on each side of the lift more equal and the motor is just a catalyst in making the lift move

Rubber bands are not what should be keeping your lift rigid lol


I agree preferably something rigid like metal keeps your lift rigid. What I mean by the rubber bands is that the lift doesn’t need to be as rigid if the force of the rubber bands on both sides are equal.

Thank you all for the help! By “ls axles”, I assume you mean low-strength/normal axles?

Careful about using a 12" axle to run both sides of a lift. Over time the axle will start to twist.

In The Zone (2017-18) robots frequently had arms that were actuated by one central motor. Set up the motor and gearing in a central assembly with one arm that protrudes. Then T off of that arm to link to your 4-bar.

Crude photo below.

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This is bad building practice. The lift should be rigid (no flexing) even without any rubber bands.

Not preferably, required

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If the load on your 4 bar is low then you can get away with it just fine. That being said, if you’re lifting a mogo you’ll definitely need bracing

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