Is it possible to lift a robot on a winch made with a 775 motor gear box 130 pound bot and lift it atleast 2 feet
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It’s possible for a hamster spinning in a wheel to lift a 130-pound robot. The question is how quickly.
If you’ve got a design goal, share it. If not, JVN spreadsheets incoming. 
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Of course it is. All you need to determine is the gearbox ratio and the diameter of the spool on the winch.
It’s possible be careful with stalling the 775 we ran one on our elevator last year, (it was very heavy) and we stalled out 4 motors last year.
Any motor will lift the robot. Depending on the gear ratio. You can use the JVN calculator to get a good idea of the gear ratio your need. Or, you can sit down and crunch the numbers yourself. I find a simple energy balance to be the easiest way for climbers.
Robot mass:
130 lbs = 59 kg (just do it all in metric - trust me)
Potential Energy Final = Potential Energy Initial (0) + Energy from Motor.
Potential Energy (PE)= m * g * h
PE = 59 kg * 9.8 m/s^2 * .6 M = 347 Joules
From VexPro, 775 pro peek power is 347 Watts @ 3000 RPM
Power = Energy / Time
347 Watts = 347 Joules / Time
Time = 1 Second
So we can climb in 1 second if we run the motor at peak power and assuming no losses. Let’s assume a 20% loss - so 1.2 seconds.
Let’s assume you are using a winch attached to a rope. A winch has a drum. Let’s say the drum’s diameter is 2 inches. Then:
Drum circumference: C = pi * d = 6.2 inches = .157 m
So for every rotation, you will climb .157 m of rope. Or, the climb amount is .157 m / rotation.
So we need the distance you want to climb, .6 m * 1 / .157 m / rotation, or 3.8 rotations. To do that in 1.2 seconds, you need 3.8 rotations / 1.2 seconds = 3.2 rot / sec or 3.2 rot / sec * 60 sec / 1 min = 192 rpm.
Since our motor runs at 3000 rpm at peak power, then we need a gear ratio of:
3000 rpm / 192 rpm = 15.6 : 1.
Now, this is all done with a single 775. And if it were me, I’d look at that number and think “I like being safe”. So maybe I’d gear is 25:1 with the two motors. That should be more than enough to overcome ineffiencies. Also keep in mind at the end of the match you’ll have less battery power, so you won’t actually get peak power out of the 775’s. So dual 775’s through a 25:1 should be nice, safe, and fast. But I’d do the math for dual 775’s just for fun - and don’t get caught trying to go TOO fast, better safe than sorry.
In fact, I’d be willing to try climbing with a single 775 at 25:1 if I were worried about weight. It would still be pretty quick, but half the headache of dual motors and motor controllers.
Finally - I always like double checking my math. I’d check this against JVN just to make sure I’m in the ballpark.
And double checking with JVN tells me that I’m going to want 2 motors, and that I’ll get up in .63 seconds with a 25:1 gear ratio. 1 motor won’t do it at that ratio. So I guess that would be my starting point!
If I were motivated, I’d go back and determine where I made a mistake or where I didn’t make a correct assumption - because being off from JVN’s calculator by a factor of 2 in my energy derivation bothers me.
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Haha pur elevator was 100:1 i think we
I was trying to get the OP thinking, rather than just asking for an answer. Climbing with a 775 Pro is quite possible, as we did it for 3 years in a row without losing one.
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Let’s take a look.
With two 775pro (or RedLine) motors in the JVN Calculator:
That would correspond with a Sport Two Motor gearbox (3.25:1), a 12:1 57 Sport, and a 4:1 Sport Heavy Duty Kickup Box for safety. (I worked at AndyMark, I think of their stuff.)
You probably could gear it more aggressively than that, but 24" off the ground is probably overkill for most situations to get to scoring position, your battery is probably close to drained for the match, you probably didn’t get everything perfect in this system, and you probably have some hapless rookie that hung right beside you that you may need to nudge out of the way. Safety margin is nice. 
I’m going to plug my design spreadsheet as the answer to your question. You can use the mechanism ratio calculator to help you figure out exactly how many/which motors you need and what gear ratio to use to get the linear speed that you’re looking for. If you have question on how to use it, feel free to ask.
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If you really want to save power, the Throttle Motor on a 10,000:1 gearbox is a valid option
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Ofc man I didn’t think of that. My bad
Thank you so much and do you think the battery would have enough power to do this twice the reason I ask this is I want to use one winch to climb our bot and drop a second hook that will winch up a second bot
Two thoughts:
- Probably, with anything resembling good battery management.
- If you’re asking these sorts of questions at the start of Week 4 of build season, this may not be the year to attempt a buddy climb.
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Yes. We used the winch below, connected to a Versaplanetary at (IIRC) 49:1. You put a 1/2" hex socket on the VP, whatever socket the winch takes, and connect via a short piece of steel square, with a screw and a nut. The winch has a (loud) ratchet in it.
https://smile.amazon.com/gp/product/B00809ZXSM/ref=ppx_yo_dt_b_search_asin_title?ie=UTF8&psc=1
we’ve wanted to do this for a while but we don’t know what motors to use and yeah its late our team lost a lot of leadership and direction when our last year seniors graduated and personally I am trying to find out the easiest way to gain more points and a buddy climb seems to be up there
but I don’t know this build season has been confusing and convoluted for our team esp our coders due to the fact we have no mentor or senior members
As someone who joined the Church of MCC (and is having his faith tested so far with our ball shooter design): The easiest way to gain more points is to have a fully shaken-down robot. I see 2872 is competing at both SBPLI Long Island Regional events, so you really only have one opportunity to shoot your shot (well, perhaps you could make some changes between the lunch break of NYLI1 and the end of practice day for NYLI2).
The fewer shiny objects you chase, the more you can focus on the remaining robot elements (say, your main climber and ball handler). I had a local mentor asking me similar questions about a ball shooter this morning, and I was talking him down just the same. (Granted, both that team and mine compete Week 1…but it sounds like your team still needs to approach shiny objects with caution.)
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Your first priority should be to find a way to get your robot up reliably and consistently. Until your robot climbs, you are not pulling up any other robot. Until you can demonstrate such a capability, possibly over several competition seasons, other teams might be hesitant to entrust their robot to your mechanisms.
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