|
|
|
 As far as the GDC being that mean, at least three of them have the pure evil genius rating, and the rest are simply pure evil. - EricH [more] |
 |
|
|||||||
|
||||||||
This is the simple hook delivery system we built to allow our robot to scale the tower for Stronghold. The grappling hook is launched through a guiding hole in a piece of plastic (delrin, UHMW plastic, wood? whatever has low friction). The orange shaft is a piece of construction site fiberglass pole that you can get from home depot. A small piece of latex or rubber bands is used to propel it upward like a crossbow, and a pneumatic cylinder holds it in place.
We built our scaling mechanism over the course of friday and saturday morning at AZ North after the pit team ran out of stuff to work on. All of the materials can likely be found throughout the pits at a typical regional (at least, they were at our regional, that's why we built it like this!)
Total weight of the components pictured is under 2 lbs.
Discussion
view entire thread
04-03-2016 10:32 PM
PayneTrain
Re: pic: Simple hook delivery system
Y'all are absolutely crazy. I love it. I caught some of the live stream; let me know if you have any prettier video available.
04-03-2016 10:36 PM
s_forbes
Re: pic: Simple hook delivery system
I should have put a video link in the description... Here's footage of the scaling from the side of the field during semis 1-2 at Las Vegas: https://www.youtube.com/watch?v=ojyvzLD55qM
04-03-2016 11:04 PM
connoc1
Re: pic: Simple hook delivery system
This is awesome! Did it ever miss the bar in matches/practicing on a bar? If it did, did it fall back onto the robot or break the extension length rule? Thanks!
04-03-2016 11:59 PM
trumpthero786
Re: pic: Simple hook delivery system
Built at an event? That's absolutely insane. How does the clamp stay open/shut (more worried about the shut part). Do you have any close up pictures of the system, particularly the rubber bands or latex you were talking about? And then how are you winching up? Is it a PTO or separate gearbox?
I know 118 did it already, but honestly, this one is so much cooler. Amazing work.
04-04-2016 12:07 AM
BotDesigner
Re: pic: Simple hook delivery system
What is terrifying about this is that it could be cheesecaked on almost all stronhold robots. I bet cheesecaked scalers like this are going to be a familiar sight come Champs.
04-04-2016 12:07 AM
Roboshant
Re: pic: Simple hook delivery system
Amazing mechanism! Especially for something done over the course of a competition! Is that a shaft collar being used to attach the fiberglass on to the hook? Also, I'm not a hundred percent sure about this but, one of our mentors said that fiberglass was not legal for use, as it shatters if it breaks and can cause splinters if not handled correctly.
04-04-2016 12:14 AM
pilleya
Re: pic: Simple hook delivery system
|
Originally Posted by BotDesigner
What is terrifying about this is that it could be cheesecaked on almost all stronghold robots.
|
04-04-2016 12:17 AM
MrForbes
Re: pic: Simple hook delivery system
heh....if fiberglass were illegal, then a whole bunch of 842's past robots would be illegal! since they had fiberglass chassis
I'm sad I don't get to see it live in action. I guess we need to win so we can go to Champs so I can see it work!
04-04-2016 12:25 AM
JohnFogarty
Re: pic: Simple hook delivery system
I'm confused. How does your hook stay open till it clamps on? I know how the 118 style one works, but this one seems fundamentally different.
04-04-2016 12:27 AM
s_forbes
Re: pic: Simple hook delivery system
|
Originally Posted by connoc1
This is awesome! Did it ever miss the bar in matches/practicing on a bar? If it did, did it fall back onto the robot or break the extension length rule? Thanks!
|
|
Originally Posted by trumpthero786
Do you have any close up pictures of the system, particularly the rubber bands or latex you were talking about? And then how are you winching up? Is it a PTO or separate gearbox?
|
Our gearbox was a toughbox nano with a 1/2" ratcheting wrench zip tied to the side: http://i.imgur.com/YwcDhV6.jpg
The 1/2" output shaft acts as the spool for the rope.
|
Originally Posted by BotDesigner
What is terrifying about this is that it could be cheesecaked on almost all stronhold robots. I bet cheesecaked scalers like this are going to be a familiar sight come Champs.
|
|
Originally Posted by Roboshant
Amazing mechanism! Especially for something done over the course of a competition! Is that a shaft collar being used to attach the fiberglass on to the hook? Also, I'm not a hundred percent sure about this but, one of our mentors said that fiberglass was not legal for use, as it shatters if it breaks and can cause splinters if not handled correctly.
|
04-04-2016 12:29 AM
Kevin Sevcik
Re: pic: Simple hook delivery system
|
Originally Posted by JohnFogarty
I'm confused. How does your hook stay open till it clamps on? I know how the 118 style one works, but this one seems fundamentally different.
|
04-04-2016 12:32 AM
s_forbes
Re: pic: Simple hook delivery system
|
Originally Posted by Kevin Sevcik
I'm more curious about what moves the two halves far enough forward to break-over and snap shut. Is it just inertia when the middle hits the bar?
|
Even if it doesn't hit a bar, the inertia of the two hooks makes them go over center when the grappler reaches the end of the rope.
04-04-2016 01:03 AM
Boltman
Re: pic: Simple hook delivery system
Very cool.
What happens when it misses does it ever have the potential to go outside 15"?
How do you aim it?
04-04-2016 07:52 AM
joeojazz
Re: pic: Simple hook delivery system
How did you use the rubber band like a crossbow if it was inside of the pneumatic cylinder. Also could you fit under the low bar with it?
04-04-2016 08:09 AM
connoc1
Re: pic: Simple hook delivery system
|
Originally Posted by joeojazz
How did you use the rubber band like a crossbow if it was inside of the pneumatic cylinder. Also could you fit under the low bar with it?
|
04-04-2016 09:49 AM
Chris is me
Re: pic: Simple hook delivery system
|
Originally Posted by BotDesigner
What is terrifying about this is that it could be cheesecaked on almost all stronhold robots. I bet cheesecaked scalers like this are going to be a familiar sight come Champs.
|
The other reason this won't be seen that often is that your second pick this year actually is really valuable and needs to play the game well, whereas in 2015 you could pick a robot that was a lot worse at playing the game in exchange for a robot that is easy to cheesecake.
04-04-2016 11:29 AM
TheOtherGuy
Re: pic: Simple hook delivery system
|
Originally Posted by Chris is me
I strongly suspect you haven't tried to add a hanging mechanism to a robot that wasn't designed for one within a 6 hour window before! It's quite difficult. Getting the hook onto the bar is the easy part. Dropping in a winch, ensuring that winch either pulls from the robot's CG or from multiple points on the robot, keeping the robot level on its way up, and programming make this a nontrivial task. I'm sure it'll be done once or twice, but this won't be commonplace, particularly for short robots.
... |
I agree that the longest part of the cheesecaking process would be locating it on the robot to align with the CG, though.
04-04-2016 12:51 PM
s_forbes
Re: pic: Simple hook delivery system
We'll already have a motor/winch attached to the cheesecake version at champs. We had a BAG motor with a 90:1 reduction attached to the spare mechanism we made at Vegas and the entire thing (hook+launcher+winch) weighed in at 3.5 lbs. The BAG motor takes about 6-8 seconds to winch up and scale.
Not shown in the original picture is an eye bolt that goes through the end of the launching tube. If the rope for climbing is run through that fixed location near the top of the robot, there aren't issues with CG.
I honestly don't think it takes more than half an hour to install a mechanism like this on a robot and get it to work. It's tough to do at a regional level since all three teams begin playing back to back elimination matches immediately, but at championships you have a bit more time and a 4th robot.
04-04-2016 01:25 PM
FRC_498
Re: pic: Simple hook delivery system
We were watching the Las Vegas Regional this past weekend and were wondering how you did that! Congrats on the win and designing an awesome simple yet effective climber! P.S. we might need to borrow that this weekend at AZ West...: 
04-04-2016 10:06 PM
fiona.crush1011
Re: pic: Simple hook delivery system
If you miss, can you retract it back in to use it again?
04-04-2016 10:24 PM
z_beeblebrox
Re: pic: Simple hook delivery system
|
Originally Posted by fiona.crush1011
If you miss, can you retract it back in to use it again?
|
04-04-2016 10:45 PM
s_forbes
Re: pic: Simple hook delivery system
|
Originally Posted by fiona.crush1011
If you miss, can you retract it back in to use it again?
|
04-04-2016 10:48 PM
IamBuild
Re: pic: Simple hook delivery system
I strongly think climb is within reach for just about everyone (To the point where I'm thinking about designing a "Climb in a box" cheesecake).With only 3.3 ounces I made a launch tube, hook, and rope that has a 95% success rate. It's shot with pneumatics and if you include the motor, winching system, and the solenoid, the whole system can weigh under 3 pounds. If you have any questions about this feel free to ask and I have some pictures of it here: https://docs.google.com/presentation...it?usp=sharing
04-04-2016 11:17 PM
trumpthero786
Re: pic: Simple hook delivery system
|
Originally Posted by IamBuild
I strongly think climb is within reach for just about everyone (To the point where I'm thinking about designing a "Climb in a box" cheesecake).With only 3.3 ounces I made a launch tube, hook, and rope that has a 95% success rate. It's shot with pneumatics and if you include the motor, winching system, and the solenoid, the whole system can weigh under 3 pounds. If you have any questions about this feel free to ask and I have some pictures of it here: https://docs.google.com/presentation...it?usp=sharing
|
Edit: Just read the line "Hook is made to rebound off the slant behind the hook on the tower to then be pulled back and grab on." This seems more feasible for the hook design.
04-04-2016 11:44 PM
IamBuild
Re: pic: Simple hook delivery system
|
Originally Posted by trumpthero786
(don't know what the sample size is, though) but it seems a little surprising with that hook design. I would expect it to fall off easily. Do you have video of you testing it?
Edit: Just read the line "Hook is made to rebound off the slant behind the hook on the tower to then be pulled back and grab on." This seems more feasible for the hook design. |
04-06-2016 05:05 PM
Kevin_Crossland
Re: pic: Simple hook delivery system
|
Originally Posted by IamBuild
I strongly think climb is within reach for just about everyone (To the point where I'm thinking about designing a "Climb in a box" cheesecake).With only 3.3 ounces I made a launch tube, hook, and rope that has a 95% success rate. It's shot with pneumatics and if you include the motor, winching system, and the solenoid, the whole system can weigh under 3 pounds. If you have any questions about this feel free to ask and I have some pictures of it here: https://docs.google.com/presentation...it?usp=sharing
|
"Do not, for example, paint, file, machine, or abrasively remove any part
of a pneumatic COMPONENT – this would cause the part to become a
prohibited item. Consider pneumatic COMPONENTS sacred."
please let me know if this would be legal, cause I'd love to use a system like this on our own robot
04-06-2016 05:27 PM
JesseK
Re: pic: Simple hook delivery system
|
Originally Posted by Kevin_Crossland
Funny enough this is actually almost identical to my original idea. I'm curious, have you passed inspection with this system yet? Is this mechanism legal, it would appear to conflict with rule R76, specifically
"Do not, for example, paint, file, machine, or abrasively remove any part of a pneumatic COMPONENT – this would cause the part to become a prohibited item. Consider pneumatic COMPONENTS sacred." please let me know if this would be legal, cause I'd love to use a system like this on our own robot |
04-06-2016 06:39 PM
Kevin_Crossland
Re: pic: Simple hook delivery system
|
Originally Posted by JesseK
It looks like it's a literal air cannon - there are no pneumatic cylinders involved. The fitting isn't modified, it's just attached. Inspection would be easy so long as the housing for the canon isn't PVC, PolyCarb, Fiberglass or other material that is prone to splintering during an extreme failure event.
|
04-06-2016 06:59 PM
joeojazz
Re: pic: Simple hook delivery system
What type of pneumatic cylinder do you use?
04-06-2016 10:57 PM
s_forbes
Re: pic: Simple hook delivery system
Ours just uses the pneumatic cylinder as the latching mechanism to release the crossbow. We just used a 1" or 2" stroke 3/4" bore cylinder. The latex tubing stores all of the energy that fires it up to the bar.
I put the parts into CAD based on memory, since the real mechanism is in the bag. Here's a better angle (click for bigger image):
view entire thread
Tags
loading ...