Robotics Education & Competition Foundation
Inspiring students, one robot at a time.

Planetary Transmission


Entry ID #: 1424
Created: Mon, Jan 12, 2015 7:24 PM

VEX robotics students often find themselves feeling very limited in their robot designs. The Planetary Transmission allows users to easily control the output of two motors without any sliding parts or pneumatics. This design is also very small, allowing students to use that precious space for other mechanisms.

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   Longarmx on 03/03/2015

@I love robots: Yep, that's the idea.

   Longarmx on 03/01/2015

@I love robots: Yes, the transmission does require two motors, or else it wouldn't work. To simplify it: one motor controls direction while the other one controls the ratio. As you can see in the robot CAD, this is how the transmission is intended to be attached. The two rear wheels are direct driven while the front two are connected by chain. You could also have the transmission connected a sprocket that is chained to both front and rear wheels for an alternate setup.

   Gkirkman on 02/13/2015

Nice job on a complex mechanism

   Kevin Boenisch on 01/21/2015

I believe that using both motors on the torques setting would only give you the torque of one motor. This was discussed on the forum a while ago, but I don't remember fully.

   robbin847 on 01/14/2015

Love it!!!! it would be prefect for robots that need to move slowly when the arm is raised and quickly when the arm is down. This could highly change the gameplay and would be amazing!!!! I like the cad and 3D mockup. Its very nice