We went to our first competition with a new robot and a lot of teams were surprised that we could lift 2 MOGOS with only one motor, so, I ask the question,
what is the biggest ratio of MOGOS to motors you could consistently do? (MOGOS : motors)
- Other (comment down below)
With pneumatics you can lift goals without any motors
Well yes, but how many could you lift without pneumatics. (Our team does not have pneumatics)
Our team’s looking to do 5 mogos with 2 motors total. We’ll let you know how it goes
I can tell you how to do 7 with 1 motor
step one build 7 passive single use clamps
step 2 build a dbr4 with one motor and lift
We are trying 4 MOGOs and rings with 2 motors. It’s very doable, you just need pistons to do it.
have fun lifting almost 30 pounds with a motor
Would it be possible with single acting cylinders?
yes, it’s definitely possible. most people use the double acting cylinders as single acting anyways, just with an external rubber band to close it instead of an internal spring.
Just make sure the thing is active clamp and spring release, because you need a lot more force to clamp than you do to release.
But how would that work with a mogo lift made out of single acting cylinders? Would at have to be on a pivot facing the other direction in order to lift it up?
well the exact geometry depends on what you’re using the cylinders for.
are you trying to make a clamp that holds a goal at the end of a lift, or are you trying to make some sort of forklift to hold and pick up goals into your robot?
This is entirely doable with v5. Tower take over teams had very massive and impressive lifts. And it only really needs to go up once
We’re trying to make a forklift that picks up mogos
Gear ratios lead to many abilities that some consider to be… unnatural.
Or alternatively, rubber bands.
yeah then you’re going to have to get a little creative with your cylinder placement.
consider this crude sketch:
when the cylinder (blue) extends, you could have either a cable, or perhaps a linkage (red) pull up on the forklift (grey), lifting it up on a joint.
a cube in tower takeover weighs 285 grams. Those huge dr4bs in tower takeover generally hold 10 cubes, so 2850 grams, or about 6 pounds. Lifting 7 mogos therefore isn’t anywhere comparable to lifting 10 cubes as it is 5 times heavier. Seeing that most teams that run a 10 cube tray typically had a 1:21 ratio, you’ll need at the minimum a 1:105 ratio to drive the lift. There will be tons of efficiency losses with 3 stage gearing, and with such a high load, the system will probably not lift and have other failure points that will break, meaning it most likely won’t work with just a single motor
you could certainly lift 30 lbs worth of goals with a single motor, though not in any way practical for competitive use. you would need ridiculous structure to support any sort of linkage, and the difficulty in acquiring 7 goals and placing them all on a lift would make lifting 7 goals at once with any amount of motors impractical.
But it would be fun to see someone try.
I never stress tested the one lift I had, the lift was just a four bar but it could lift from the from or back, making the mogos weight counteract the mogos on the other side. It was built for two and probably could have held more. It used only one motor and was great, but it was just not right for what we wanted. :,( you will be missed
Do you have any videos of this robot in action you would be willing to share?