Winch

[edomus]

Has anyone thought about how to winch themselves up to the bar. I was thinking about taking apart a boat trailoring winch and using cable. Any ideas?

[Meredith Rice]

Originally Posted by edomus

Has anyone thought about how to winch themselves up to the bar. I was thinking about taking apart a boat trailoring winch and using cable. Any ideas?

Yep. Looks like this is a popular idea. I know we have been considering it. Here is a thread with a discussion about how winches work and some opinions of them.

http://www.chiefdelphi.com/forums/sh...ighlight=winch

[Tytus Gerrish]

ive desinged a winch
its a Plug&Play winch that reals 15" Per second with a max lift load of 486 Lbs

[Jeremy_Mc]

I don't want to thrash, insult, or even knock the idea of a winch (trust me we would be using one...), but given the 10ft/s rule, how do you plan to address the case of missing the bar with your winch (I'm assuming you're throwing it or somethng of that nature)?

[Tytus Gerrish]

were talking about winches not about how your getting the cable up on the bar Save that for elsewhere

[edomus]

Originally Posted by Jeremy_Mc

I don't want to thrash, insult, or even knock the idea of a winch (trust me we would be using one...), but given the 10ft/s rule, how do you plan to address the case of missing the bar with your winch (I'm assuming you're throwing it or somethng of that nature)?

Use some other mechanism, such as a arm to put the hook up

[deltacoder1020]

a great big old helium balloon!

[Gadget470]

Clarification Post: Please do not follow-up on this

Originally Posted by Jeremy_Mc

Quote 1:
I don't want to thrash, insult, or even knock the idea of a winch (trust me we would be using one...), but given the 10ft/s rule, how do you plan to address the case of missing the bar with your winch (I'm assuming you're throwing it or somethng of that nature)?

Originally Posted by Gadget470

Quote 2:
Tytus made a good point that this is not the place to discuss methodology of attaching a winch to a surface. However, note: The bar is 9' from the platform and probably 5' from the average robot's winch "launch" point.
Vmax = 10 f/s
or
Vmax = 5 f / .5 s

I don't think it will be too much of a problem to "launch" a latch by a vertical means in over .5 seconds. Yes, I understand that a vertical launch is different from an arc'd launch, but you get the idea. 10 f/s is pretty darn fast.

Originally Posted by Mike Norton

Quote 3:
I would not launch anything, I would use a arm to deploy the cable. then bring the arm back in.

Sorry I didn't clarify, my point about the Vmax was intended towards Jeremy_Mc's coment earlier in the thread.

[Tytus Gerrish]

i just tested whe vandoor motor with a 1.5" spool on it. with no power i just leand back with the cable in hand and iot was backdriving

[coreyjon]

Originally Posted by Tytus Gerrish

i just tested whe vandoor motor with a 1.5" spool on it. with no power i just leand back with the cable in hand and iot was backdriving

When I started thinking about how I was going to pick up the robot this year, I also thaught winch, and at first I thaught van door motor, but yes, that darn backdriving thing killed that, So, I looked at some of the other motors in the kit, and I decided on using the globe motors, now each globe produces 150 in-lbs of torque, not too shabby, but cant have a side load, not a real big issue, as long as you have good bearings, and a tight assembly with little slop. it runs at about 100 rpm's no load, and that gets cut by a little more than half when there is this much load on it. now, you could get away with just one globe motor, and say a 2 inch dia. spool, would give you 150 lbs of lifting force, but it would be slow, you could increase the spool size, but then you loose force, again it would be slow, and one thing is, you don't want to sacrifice twenty seconds to just lifting the bot. so, like everything I've designed this year, im using two motors, and a drum, which will provide over 300 lbs of lifting force, and I can tell you it will take less than 5 seconds to live the robot two feet off the ground.

example:
torque(in-lbs)=force(lbs)*radius(in)
300in-lbs = 300lbs * 1in.

power(hp) = force(lbs) * radius(in) * rpm / 63025

If we know the hp rating of the globes, which we do, and it is just over .2hp, (.21hp), you can find out the rpms of the motor under a specific load.

yes, it really is that easy. but if you do use the globes, make sure whatever your turning is supported right, and with bearings, so that the motor dosnt see any side load, because no good can from that.

[Mike Norton]

Globe motors are good for lifting the robot but we use it not on the winch but as a lifter to get over the 6" side. We use the globe as it came and gear that down to 12:1 we only needed to turn the last sprocket 1/4 turn. so it takes 1.8 second to lift our robot 8 inches off the ground

http://www.valleytech.k12.ma.us/robo..._24wheels2.JPG


The winch we are using the Tyco motors and gear them down to 200:1. we are making our own gearbox and putting both Tyco motors into them.

We go up at a rate of 18" per second. pretty fast with power. This way if we have to go from the carpet we should be there quickly.

[M. Hicken]

it was kinda funny but dangerous at the same time last thurs, we were testing out winch w/ one of the guys standing on a platform he mounted to winch to, a combined weight of about 160lbs, a 500 pound test aircraft snapped like fishing line. Anyone else think we got jipped on 15' of cable?

[Shawn60]

We have designed a winch that is "attached" to one of the gear boxes. We will have then have a low (power) and high speed wench. I will post some pictures of it when we are done. I believe we are using stainless, boat cable. It's breaking point is at 1,200 lbs. We shall see if it all works in the next couple of days.

Shawn

[Arefin Bari]

the winch looks nice tytus... seems like you are suggesting to use chiphua motor which is also known as atwood. there are lot of teams out there who would use the chiphua for drive train... a lot of team out there had drill and chiphua using for drive train last year, and they might do it again. what would you suggest using some other motor such as window or globe... its probably gonna take a while for the winch to move... but there is going to be a lot of torque...

[SarahB]

Originally Posted by expiredzbyte

the winch looks nice tytus... seems like you are suggesting to use chiphua motor which is also known as atwood. there are lot of teams out there who would use the chiphua for drive train... a lot of team out there had drill and chiphua using for drive train last year, and they might do it again. what would you suggest using some other motor such as window or globe... its probably gonna take a while for the winch to move... but there is going to be a lot of torque...

Actually I think he's using the van door motor. Notice the gearbox at the end. This is better than using the CIM because the van door motor uses a worm gear, which means it cannot be backdriven(at least theoretically) so you don't have to worry too much about it falling after power is cut at the end of the match.