Weight Lifting Robot

Hello, so I have a school project where we are supposed to built a vex robot under 8 pounds, that can lift up to 12ish pounds. We are supposed to have one round of automation and one round of remote control. I have the code, and I was wondering, how do I make a lifting mechanism? I will link some pictures below of the arena, we are using an holonomic/xdrive drive train and are not really sure on how to built a strong lifting mechanism, any help or sketches would be appreciated. The weights will be of various weights including 2.5 Lbs, 2.27 Kg, 4536 grams, and 0.46 Slugs.

The weights will be like this:

The field will be like this:

PS: The red barrier will be 1.5 thick x5.5 inches tall, the robot will have to lift up the weight and drop it in the barrier.

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I would recommend look at robots from last year as teams had to lift objects. Pretty much every team with a lift used a four bar. For additional lifting mechanisms see Lifts - BLRS Wiki

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Lots of gearing down (for torque)

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If you have accsses to pneumatics the cylinders are conveniently rated at 12lbs at 100 psi. This is somethingn I have “tested” by filling last years mogo with screws and steel. With some clever use of levers you could likely create a lifting system useing them.

But I would suggest a 4 bar lift like Pilot recommended if you just have motors.


Feels like you posted same picture twice and other rules are missing. Like is the time unlimited for the task? How is it scored? What are the other constraints?

Seems like one if the images auto cropped, sorry about that, and yes there are a few more constraints, I will just copy and paste the rules as follows:

Time sequence will be as follows:

-4:00 Competitors are announced and they move to their respective areas to prepare their robots.

0:00 Competitors release their robots to retrieve resources from the playing field.

+5:00 Time is called and resources are totalled up.

+1:00 Teams have one minute to remove their robot to a remote staging area.


  1. Resources will be of various weights including 2.5 Lbs, 2.27 Kg, 4536 grams, and 0.46 Slugs.
  2. Robot may weigh no more than 4.0 Kg unloaded. This is because you are very weak from not having enough resources before finding this field. Any robot that weighs more than this will be penalized 1 point per every 2 oz’s overweight.
  3. The robot must transport the resources over a red or green colored 1.5x5.5 inch barrier for them to be secure.
  4. The robot may not be any wider or longer than 61 cm.
  5. The robot may be picked up from behind the barrier and re-positioned or re-aimed, but it may not be controlled remotely during the autonomous session. It must rely on sensors.
  6. If someone must step over the barrier to retrieve an errant robot, then that must be declared before the barrier is breached. Upon declaration, there will be a mandatory 30 second waiting period before the robot may be placed into the field again.
  7. You will receive one laser Distance Sensor and one Color Sensor. You may trade with other teams or request additional units of these sensors with a justification and plan for their application.
  8. Limit switches, bumper switches and other electronic sensors or units are available upon request.
  9. Motors and gearing are both available. 393 and V5 motors are both available.
  10. Upon completion of the competition, there will be an additional 5 minute competition at the teacher’s discretion. However, this competition will be utilizing the Remote Control units to gather the resources.
  11. Resources that are placed behind your barrier will be safe. Until a resource is placed behind your barrier, it may be moved by any competitor’s robot.

Unfortunately I dont have acess to pneumatics, I will definetely try a 4 bar arm, thank-you!

Thank-you! I first throught about a linear slide that uses gear ratios for torque!

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Thank-you so much for your help, I will look into this idea more, and after I build it I will tell you guys about it!

In the competition, we will have one autonomous, and one rempote controlled competition, the robot will have to lift the weight on its own, and come and put it back in our cubby autonomously, in the second competition we will have to remote control the robot, how would I make the 4 bar arm autonomous?

The robot will need to grab the weight by itself and then lift it up, and carry it back without tipping over as welll.

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