Lifts with Green (200RPM) Motors

We are trying to build a simple 4 bar lift (similar to AMOGO) but we only have the green motors so even with a 1/11.25 gear ratio. We even tried rubber bands but it don’t seem to lift up mogo What should we do?

p.s. Idk if this will help but instead of using high strength axles like the original one we mount the gears using nuts and bolts (with bearings)

At one point during development of DOGO, the four bar used a green cartridge. With some rubber banding, this had enough power to lift up a mobile goal. The mobile goals would sometimes come up too fast and get caught on a part of the drive, or slide a little while coming up and not engage with the lock. We felt going a little slower was okay, and fixed these issues.

Team 2145Z has a public reveal with a forklift that uses a 1:5 with green cartages. From my testing, I believe tihs will need a little bit of rubber band support.


The four bars on AMOGO and DOGO use a 1:5 ratio (the metal 12t to the plastic, high strength 60t) with red cartridges.


The HS axel that went across the 60t gears helped keep the left and right side in sync with each other. Doing this means you can have a little less bracing.


Could you post a picture of your mechanism?

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@Unionjackjz
This is the image (sorry it took a bit long to take). The difference would be that we used straight pieces instead of the angled ones, For the connecting between the gear and 4 bar are just bent metal plates.

This looks pretty good! These are in order of importance.

If you have them, make the motor a 100rpm cartridge. The speed of the mobile goal lift should only make this work better.

Check your friction on all of your joints. I see you’re using screw joints (yay!), but make sure you don’t overtighten the locknuts. The goal is to use the locknut in a similar way you use a collar on a shaft, you’re just trying to keep the joint on the screw. You want the joint to be able to wiggle just a little bit.

All of these parts look like steel, and steel is much heavier then aluminum parts. If you’re able to replace some of them with aluminum, the entire mechanism will be much lighter and it’ll be easier for the motor to move it.

It looks like your 84t gears are cantilevered? Try adding another support to the inside of both gears. This should be enough, but you can also replace the screw joints with a HS axel.

Flanges increase the strength of a part. Imagine bending a piece of flat, and compare that to trying to bend a c-channel (but don’t actually bend them :D). The longevity of the flats is concerning to me. Robot use can get pretty rough, and if that gets hit I’m afraid it will bend.

Let me know how it goes!

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