High Hang motor problem

To prepare for VEX WORLDS, my team decided to make a hanging mechanism. Even though our robot has 6 torque motors dedicated for the lift(4 running off of the power expander, and 2 running off of the main cortex battery), the robot doesn’t really seem to lift itself up quite easily. Currently the lift itself has a gear ratio of 1:5. Is there any way to make the lift stronger so it can hang more easily while not actually making the gear ratio bigger?

also, even though the picture has the rubber bands, we tried lifting without them
Screen Shot 2017-03-05 at 12.31.02 PM.png

Your link to your pic isnt working.

You would need to shorten the arm. Can you move the hook closer to the middle of the lift instead of the end?

oh… crap…

Why not use the lift for hanging?

no, I am trying to…

but then the motors seem to be too weak… they are almost brand new though
Screen Shot 2017-03-05 at 12.31.02 PM.png

Sorry it just sounded like you were adding a separate mechanism for hanging.
I can’t quite tell whether you have rubber bands on the lift, and also what is your full wiring set up.

but then with the lift being shorter, it is kind of impossible to get the stars over the fence… :frowning:

um the black line things are actually latex rubber bands. Also, I run 4 motors on the lift by the power expander battery, and the other two from the cortex.

ps: the ones on the power expander (4) are actually y cabled

About on average how many stars can you pick up in a load. And, how heavy is your drive.

about 3~4…

also, my drive, if you mean the base, has 4 motors, and both batteries attached to it.
and I don’t really use that much aluminum on my base also

Ok so my earlier robot in the season had a 6-motor lift with a 1:5 ratio and it had the strength to pick up 7 stars and it hung in 5 seconds. It sounds like you either have too much friction in the arm or your base is too heavy. Also check that when it hangs that the anti tipping mechanisms are not preventing it from hanging.

so basically, my robot’s total capacity is about 1 cube with 2 stars, or just 2 cubes, or about 6 stars, however, I don’t know why, but then when I remove the anti tip and attempt to hang, it goes about half way, then just stops there, and doesn’t go up

I don’t know, but just to ask for advice, would it be better to just rebuild the whole arm again?

also, can I see a picture of your current robot?

Oh, ok this makes more sense, with this capacity. After it “quits” halfway up the hang, can you drive it too see if the arm is burnt out or not.

ok… but then I don’t have the robot right now to make sure,
however in my own experience, the arm would operate just fine when taken off the hanging bar.

I really don’t know why this is happening . :frowning:

maybe I should actually just move the battery somewhere else

Is there any way that we could have some more pictures of the arm and hanging mechanism. It does sound almost like the PTC is tripping, I am guessing that it falls down after going half-way up.

um… to do that, I’ll get a picture of the robot close up later on, because right now the robot is at the school, and I can get there by monday. And also your guess is true, because it falls down after going half way up

however, how do I prevent from the PTC’s from tripping?

That was why I was asking for your full wiring setup, I guess I should have specified. Basically, the brain has two circuit breakers, one on port 1-5, and one on port 6-10. If there is too much power being pulled from one of the circuit breakers than it will cause a PTC trip and all the motors will shut down on that circuit breaker. So I would check that you have all the motors spit up on the brain, I.E. three arm motors on ports 1-5 and the others on 6-10, etc.

hm… probably yes…
so basically, even though I am using a power expander, I would still have to actually readjust where I actually plug the lift wires?