Looking for ideas on getting the robot down safely from traversal rung. What are other teams doing? Currently looking at these Forearm Forklift
We will be picking our robot up off the rung and then setting the robot down, ideally without dropping it most of the time
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We are planning on using our cart and lifting it up to the robot. If needed, we can have team members lift the robot up and off the rung as well.
That reminds me…we need to install the handles on our robot soon.
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you will not be allowed to bring your cart onto the field.
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Ah yes, thanks for reminding me of this. In that case we will just have team members take the robot off the rung and set it down.
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This is exactly how my team did it! Of course, that doesn’t solve all of the issues but at least it gives the technician (and helper!) a convenient place to lift the robot from.
This year, it sounds like our robot is right about 100lbs, so lifting is less of an issue than it usually is, when we’re drilling holes in our wheels to save weight, whoops… Otherwise, just make sure you lift with healthy posture, and between two people, it should be decently safe.
I’ll have to check in and see if they have any other tools or methods this year to help!
-E
Our drive team has started doing two things:
- Hanging out robot on the traversal bar to work on our electrical belly pan.
- Using the robot to reverse climb down the bars once we have finished our traversal climb.
Obviously neither is feasible for competition but watching them reverse climb the bars was an experience.
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Ooh, interesting! It sounds like our robot can’t safely climb back down the bars, but that trick for working on electrical is pretty handy! Very neat!
This is an important conversation ! Safety third (as Mike Rowe says).
Analyze the task:
Step 1: lift up to release hooks
Step 2: controlled lowering to floor
Step 3: carry off field usual way
Requirement 1: avoid imbalance of two humans lifting at different rates on opposite sides
Requirement 2: avoid risk of bot falling/being dropped on a human
Requirement 3: avoid humans straining their backs
Requirement 4: quick attachment and release of equipment (if any).
Solution: Top-rope belay the bot down similar to belaying a human rock climber.
- Have attach points on the bot (to function like the harness on the human climber).
a. Could be as simple as a large eyebolt near the center of the climbing mechanism.
b. Or an upside down V whose ropes are attached to 2 eyebolts at the sides. The apex should have a butterfly knot or similar for the belay rope to clip into.
c. Or 4 ropes like a pyramid to the 4 corners of the bot.
d. Choose a method that has little chance of entanglement with the climber or other robot parts. - Throw the belay rope over the traverse bar. An eye splice in the end would be cool. Clip into the “harness”
3a. Standing right beside the bot, the 2 belayers can wrap the rope “around their butt” for friction.
3b. Walking back a short distance should release the hooks (traverse bar acts like a pulley) [Step 1]
3c. Feeding the rope out lowers the bot as slow or fast as they like. [Step 2]
3d. Unclip the belay rope, unclip the harness.
Then the bot can be carried off the field by the team’s usual method.
Note: safely lowering the bot after game end is simpler than keeping the bot safe while it is climbing (no translational movement of the bot to keep up with).
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@rlance From the pictures the forearm forklift seems to need flat surfaces to put your palms against. Will the robot have these?
It might be good to have 3 or 4 people working together to take the robot down. It would probably also be good if they were of similar height. Otherwise, the tallest person gets more strain than the others. Lastly, it would be good to smooth over all sharp edges near where one normally grasps the robot chassis as well as other places nearby that may get grabbed “in an emergency”.
I always want to be above the robot when I lift it in order to use my legs to maintain good lifting principles. As the rungs aren’t really all that high I should be able to scamper up them and pull the robot off that way. Once I have good positive control getting it down should be simple. Firefighter trampoline maybe?
You might want to have a look at H108.
They aren’t monkey bars.
On the overall topic of getting robots down from the Traverse rung, I would like to point out that this is only a problem if the robot gets up there first. Good problem to have!
After seeing the final robot hanging positions for most of the robots climbing to the trav rung in reveal videos and week 0 events, it appears that the bumpers are between knee high and waist high for all the released designs. That should be a comfortable lifting height to lift it off the rung and lift it down. The biggest challenge will probably be keeping the extended arms from getting tangled on the truss or other robots.
Which brings me to my proposal for a change to the title of this thread: Safely Getting THREE Robots Down from Traverse Rung. Now that is a FIRST Worlds problem!
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Starts with someone eating a shoe. Ends with all three robots on the floor. Middle? What, you expect us to plan such things?
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We made some of these today. They were so good our lead mentor said “if I knew they worked so well we would’ve done it 10 years ago.” Great design!
It’s interesting that people are mentioning lifting but no-one has mentioned rope.
Wouldn’t four eye-hooks around the center of gravity which you then thread a rope through (it wouldn’t be too hard to learn how to do – I’m sure you could find a video or something) work? Then loop the rope over the bar (a couple times if you want friction help) and slowly release. With a robot weight limit not much heavier than a person, this could be easily accomplished.
Sure, it’s a bit complicated, but if you’re actually worried about just lifting it off with people, that’s always a possibility. I’m not sure if bringing rope and spending some time removing your robot is legal, however.
(I realized this idea may seem stupid to me in an hour or so but whatever.)