MERGED: Universal Hanging System/Standardized Partner Suspension

[Chris is me]

Originally Posted by demosthenes2k8

Um, chris? I'm pretty sure that a standard would make a single system, so the robot would only have to grip one type of object. Your argument needs to be inverted.

I like the standards ideas, but I'm not sure how easy it'll be to get everyone to go along with it.

My post's wording sucked so I'll edit it (tends to happen to me a lot) but I was basically saying making a standard mount based on something other than the field bar would not be advisable. If teams include a section of field-like bar on their robots, then existing grabbers can be adapted to it.

[Shawyan]

I fully agree that there should be some standardized hanging system identical (at least in size and shape) as the tower par.

Unfortunately, many teams will have a problem for this because of space. I see this getting in the way of pendulem type kickers (especially considering this changes the weight distribution)

Ideally, the bar would go across the middle of the robot, at hopefully two points. Any more than that and connecting is too difficult.

Also, if the connection is not perfectly balanced, Tipping will be an issue, and it may fall under the platform (20" if I'm not mistaken), and no points will be awarded for that extra robot.

Just some potential problems that need to be worked around for a standardized system.

[EversmannJ]

Originally Posted by Mr. A

Another approach is for each robot to have a bar on top that is a handle allowing it to be lifted from above. ...it would be easy for any robot to have the handle and not need a lifting mechanism.

The idea of making a robot capable of grabbing both the field's bar and another robot's is really good. Anyone who's robot can't lift itself for some reason should definitely go for that.

[vansivallab]

I do not think its a good idea to put the par on top of the robot, though you could raise the other robot (the one that is suspended off of your robot) higher, you would restrict the designs of many teams since, unless they come up with a way to raise and lock it into place, their robots will be too tall to fit in the tunnel. But we can make it so that the bar is at 18 inches, so the robot can fit through the tunnel, but I guarantee you if we do that someone will place their vital components near that bar (electronics, $1000 CRIO, etc) and which could get ripped out by another robot.

I just feel, in this case where we want to make wide sweeping standards, its a good idea to make it simple, so even a rookie team can install it w. out quams. So I think we should go back to hanging it at certain length from the ground (im thinking 5 inches) so it can act as a guard and the robot can use the tunnel as per their design. As our dear old friend Murphy says, "Anything that can go wrong will go wrong." So lets keep it simple, since I don't want to see robots falling from 7 feet.

[dtengineering]

Wouldn't it make more sense to link the robots together while they were still on the ground... and just have one robot do the lift?

Jason

[Donut]

While nice to try to set up a standard, to have wide sweeping success I think the only standard that is likely to work is one based upon a replica of the actual tower bar teams can hang from. Why?

The majority of teams at competition will not have seen any threads on this on Chiefdelphi and will be unaware of any standards you create.

Many teams don't even use CD and those that do still may never notice a thread like this. So, the best way to ensure that their robot could hang from yours, is to design your robot with a system that lets them replicate the motions of hanging from the tower. Then they can hang from you with zero modification of their robot and no prior knowledge of what your design was.

Something to keep in mind here.

[Salbert]

I guess as long as you have a simple, easy grip bar extending along the entire rear of the robot below the bumper, it shouldn't be hard for other robots to grab. It should stick out as far as possible.

[Salbert]

Originally Posted by dtengineering

Wouldn't it make more sense to link the robots together while they were still on the ground... and just have one robot do the lift?

Jason

Lifting as many as 360 pounds (3 bots) would result in the lifting arm and robot being ripped apart if there wasn't enough power.

Or in a less violent scenario, it simply wouldn't be able to lift anything and stay on the ground.

But lining up 3 robots in a chain before lifting up in 20 seconds would take too long.

[IdaNeStr3088]

This idea is great
Team 3088 was thinking about building a small metal frame in the back of the robot, like the attach point to the trailer in last year's game(Lunacy) but make it more wide and more accessable for the other robots to reach.
If you have a comment about the idea or you ahve other ideas feel free to do so.

-Idan

[Tytus Gerrish]

What's the big deal? The robots only need a static part that resembles the tower bar. Seems completely straight forward to me.

[frank.pendzich]

We're considering a strategy where we don't hang from the horizontal rails at the top of the tower, but the verticle supports. Are the towers secured so they can support a robot hanging off the side of the tower?

[thefro526]

Originally Posted by Tytus Gerrish

What's the big deal? The robots only need a static part that resembles the tower bar. Seems completely straight forward to me.

Seconded. I would also suggest making it a very bright color that's easy to see from 15 feet away or so.

And just some food for thought, there are going to be a lot of teams that aren't going to be sold on hanging from your robot, I for one am completely opposed to the idea of trusting anyone enough to attempt to hang their 150lb (yes I said 150lbs, 120lb robot + 13lbs + 15lbs bumpers = ~150lbs) robot from our robot and vice versa, so you're going to have to sell whatever hanging mechanism you have to your alliance and prove that it has a safe working load of 300lbs for two robots and 450lbs for three robots.

[GaryVoshol]

fro has a good point. If the top robot's grip fails, it will fall down onto your suspended robot.

[PAR_WIG1350]

Think more like '07, or, mount the bar so your alliance partner hangs next to you. using 2 grippers, grabbing 2 different sides of the tower, will counter any balance issues.
...@................@............................. ..............
....Y=========Y==O................................ ......
........................../........................................
........................./.........................................
......................../..........................................
......................./................O=======@..........
....................../................/I.............Y...........
.....................O==========......_____I_____. ..
......................I__ robot1___I.....I__robot2___I..
......................\_/...........\_/......\_/..........\_/..
......................(_)...........(_)......(_).. .......(_)..
O hinge/joint
@ Bar
Y grabber
(_) Wheel
.... nothing
robot 1 hangs from the tower
robot 2 hangs from robot 1

Now, robot 1's grabber is redundant to some extent, if the right, load bearing gripper fails, robot 2 will hit the ground, but robot 1 won't fall on top of it. if both of robot 1's grippers fail, they still only fall near each other, rather than directly on top of each other.

[Nurnburger]

One key thing about placing the bar underneath your robot is the tipping factor. If someone latches onto it, it could tip your robot sideways. Though this isn't a problem for winch systems, arms could get busted off sideways. Also, if someone's hook slides all the way over the side of the bar, it could get caught is some things that maybe it shouldn't.

I think it might make sense to put two supports on the bar in addition to the end supports. This would allow suspended robots to stay more or less in the center of your robot, and it would provide more support to that bar.