So our build went longer than we would have liked, partly due to a lack of hangars to test on, but we finally were able to test our climber on some hangars. We ran into some major issues with chain stretching and skipping in addition to gearbox mounting issues. In the end, were able to climb 3 times consecutively and would be able to continue to the traversal rung if we had it built. These climbers are quite tricky and we recommend teams leave ample time for testing and tuning, as a lot of parts can break. Here’s the video!
that’s excellent. great job!
That’s awesome! Out of curiosity, is there a reason why you tilted the entire robot instead of just tilting the lift?
because of the limits to your extension out of your frame perimeter.
That’s fantastic! Nice work! One question, and I know this is only the preliminary iteration, but are you planning on figuring out how to traverse rungs without the full robot swing? I only ask because from the video perspective, it would violate R105 & G107.
It doesn’t violate R105 and G107 because as far as i can tell nothing leaves the frame perimeter. the elevator stays in place and the pivoting hooks are built to be inside the frame at all times. the frame perimeter doesn’t stay flat relative to the floor it pivots with the robot.
Ok, excellent! It was difficult to tell if the fixed arms swung outside the perimeter potentially when it was swinging from the lower to the upper rung.
How would the fixed arm swing outside the frame perimeter, if they are indeed fixed on the robot, and not articulated? If those fixed arms are in the frame perimeter while the robot sits on the floor, than there is no way for them to leave the frame perimeter during the climb (barring catastrophic failure to your robot)
Fixed arm, meaning non-telescoping. Their non-telescoping arms are on a pivot that allows them to swing outside the frame perimeter, and that’s what was difficult to see in the video if they were outside of that 16" allowance.
AHHHH, in that case your question seems much more of a valid concern. I fully thought from watching the video that it was the telescoping arms that were pivoting. A closer second watch (ok, fine, 6th watch for me this morning ) makes me think you are correct in that the non telescoping arms are what pivot.
It simplifies the mounting of the elevator greatly. A tilting elevator would require rotating gearboxes. It would be doable I think, it would just require more planning.
Also, as wilson pointed out, it’s easier to stay within frame perimeter if the entire robot tilts.
the rotating arms stay within frame perimeter throughout the climb. when fully rotated forward (towards the shooter), they are within 16” of perimeter. but if you rotate them all the way back, they can go past that point. however we do not have to rotate them towards the back much, just enough to clear the elevator.
That is great stuff.
Is there a reason you went with a motor/chain setup, instead of pneumatic cylinders, for rotating your “passive” hooks, given that it’s just a 2-state system?
You beat me to the question @ClayTownR
I don’t think they have pneumatics on this robot.
mainly bc it’s not exactly two states. there are some fine movements we do to clear the bars. also we were trying to avoid pneumatics for space saving
Looks like you are taller than the lowest bar since you are driving in from the back instead of from the front. Will your fixed bars/hooks or your lowest elevator level clears the lowest bar?
Another potential reason for running with the motorized pivot, is I’ve been wondering if you can make the system rigid/robust enough (and fast enough I suppose), could you use the motorized tilt to help stabilize your swinging robot faster than just letting momentum/gravity do it’s thing?
our hangars are not at the right height. but when the elevator is lowered and our arms are pushed a little forward, our height is 43”, so we should be able to clear the lowest bar. but with the direction of our hooks, we would probably want to approach it from the back since we climb backwards.