Risk of the Lift?

[Brandon Holley]

Originally Posted by 3@G13_1388

It is almost going to be impossible to use a lift to elevate your alliance's robots. It is going to be impossible because pneumanic cylinders are not going to give enough force to exert a lifting device.

im pretty sure that the pneumatic cylinders come in larger sizes than they gave us so i think it will be possible to lift other robots with a lift. and i thin the largest size is a 2 inch cylinder.

Cmon man you gotta put up a better argument than broad statements like "its almost going to be impossible..." or "im pretty sure..."...If you think teams cannot be lifted with pneumatics, you might wanna scroll through CD-media back to 2004 where quite a lot of teams used pneumatics to lift there 120lb+ selves............VERY SUCCESSFULLY

Get creative...impossible is a dangerous word my friend

[pascoea]

Why are you limiting yourselves to pneumatics? There are MANY more options that would work just fine.

And I would agree, things that were impossible 10 years ago are now old news.

Keep the good ideas coming.

[Alex.Norton]

Why can't pneumatics lift? We used a 2-inch cylinder in 2004 to lift our robot and that was pulling. If you look at the math that 2-inch cylinder (the actual piston was probably smaller, lets say 1.5 inches) has 7 square inches of pushing power. At 60 psi that means that cylinder has 424 pounds of force. Now lets lower that estimate some for efficiency and put it at a mere 300 pounds just for fun. That means that with the number that our team currently owns (two) we could lift 5 robots off the floor to a height of about 3 ft. If we didn't lift us then with two we could lift every other robot on the field. They have more than enough power to lift your entire team.

However, I don't think that would be the way to do it cause that takes a long time to charge up for (and more than all of the storage that we got). I think a motor winch would be better suited. Also why is a lift more dangerous than a ramp? When rolling up a ramp the robot is moving on a very narrow surface and might drift without the driver being able to tell. When a lift is working then all of the force is vertical, that robot only moves up and not laterally (hopefully). No lateral force result in no lateral motion and so how does the robot topple? If the lift is done well I bet that it’s safer than a ramp cause it can be better automated.

Just a couple of thoughts

[Daniel_LaFleur]

Originally Posted by firstbots195

It is almost going to be impossible to use a lift to elevate your alliance's robots. It is going to be impossible because pneumanic cylinders are not going to give enough force to exert a lifting device.

The 2" Bimba cylindar has a push factor of just over 3. So 60PSI in the cylindar will provide just over 180 pounds of pushing force . In other words, a single 2" cylindar has the pushing force to lift a robot.

Believe me, there will be a LOT of successful lifts.

As far as which is safer ... both are just as safe. The same amount of energy will be in either design because you are raising the robot the same height. Damage occurs only when that energy is expended (IE a robot hits the floor). The difference is who's in control of the robot at the time of an accident .

[zander_108]

Now i dont know if this idea is good for use.. But what if you had a bar extend from the "lifter" robot on both sides, and other robots had their own lifting mechanism that would pull themselves up? it would be like 2004, execpt you must make it at least 12" of the carpet.

[Imajie]

The only problem is if only one hangs, then they will both tip unless you have a way to stabilize yourself

[Zoheb N]

Originally Posted by Imajie

The only problem is if only one hangs, then they will both tip unless you have a way to stabilize yourself

This is very true.. that is why team 118 had 2 arms on our robot chainzilla during the 2005 competiton. We had noticed after getting a certain height off the ground that more weight on one side made the robot tip over more so we added a second arm to balance the weight and always made sure that both arms had a tetra on them.

[sanddrag]

If your robot cannot survive a 12" fall or a tip over onto it's back or side, you need to build it a bit better. That's my opinion. Robots will inevitably fall with or without platforms/ramps.

[Mib]

I think the best thing to do would be to test your ramp with last years robot, or with a human being on a cart (some kind of a test object)

[cgredalertcc]

Originally Posted by Mib

I think the best thing to do would be to test your ramp with last years robot, or with a human being on a cart (some kind of a test object)

Amen pull last years bot out of moth balls set it up just like you are planning on having the other robots doing it and give it a try. Worst case scenario you drop a robot you probably won't ever use.

[Alekat]

I don't think we can determine which method is more dangerous since you can't know exactly how those two options are being accomplished. But if someone messes up their bot driving up a ramp it's their fault, which could be a different story with a lifter, so I'd opt for the ramp.

We've been thinking about a ramp that has a sort of jack underneath it to level out the ramp and raise your ally's bot. I see this as a combination of the two methods.

[hallk]

I think the practice fields will be full of teams praticing lifting to lower the risk. It would be nice if at the regionals there could be the practice field and then also an extra spot of carpet that the teams could practice lifting on.

[Alekat]

That sounds good on one condition. A big sign that says "Weight Room" must be placed somewhere nearby.

[cgredalertcc]

This is my personal apology for my "attitude" earlier. Turns out after crunching the numbers lift = lighter than ramp. So drum roll please 1741 is.......lifting!! We'll see how it works. I do have a question. If we were to use honeycomb (the metal used for certain surfaces on comercial air craft) and used glue to attach the skin is that within the rules? As they read it says that you may not use adhesive back tapes, but this isn't tape so I think its legal but I wanted other opinions if you wouldn't mind.

Thanks

[Priyadarshy]

remember last years ramp was pretty steep and also made out of diamond plate neither of which are requirements for anyonesramp