A recent discussion has been going around my team pertaining to getting a hanging mechanism on our robot; however, we are using all of our motors already. We are willing to only give up one of the motors to use for a hang. Some question I have about a 1 motor hang is as follow:
Is it possible?
What gear ratio would we need to lift our robot? (approximately 17 pounds)
What kind of strain would that put on the motor?
Would it benefit us to just not go for a hang?
I have asked a couple of robotics coaches from other schools, and I got mixed answers for the questions I had. As for my team, they think it is not possible to have a 1 motor high hang. Any and all help is appreciated. Thank you
We use a two motor high hang that uses a winch to lift ourselves. However if you use HS gears (like a 60T or 84T gear), high torque gearing in the motor, and a vertical track / rail, you could achieve the same thing.
A one motor high hang is possible but it is also slow. To be effective it needs to be fast. In my opinion leaving the motor where it is would benefit you most
Can you post a picture of your robot? Many teams are using the motors for the arm to also power the hang. You may not need to change the motor configuration, but just add something simple to the structure.
@Elohssa We have an 8 motor drive, 1 motor for an H-drive, 1 motor for an arm to knock stars off of the fence, and 2 motor for a plate that extends forwards to help push the scoring objects under. We talked about taking the “star knocker” motor and using it for a hang instead.
Because I was curious, I held onto the extending plate while retracting it, and I was able to get the robot to lift; however, when I stopped retracting it, it stared to lower itself because of the weight. Both of the motors for the front plate extension uses a 1:7. So, I’m thinking a possibility for the gear ratio (assuming we don’t winch it) would be somewhere around a 1:49. I was, however recommended a 1:25 which I don’t see working.
If you’re reliably clearing the field in skills and you have 15 seconds left with nothing to do, a slow high-hang ** migh ** be worth it. But you’ll be changing a working robot, decreasing the effectiveness of, say, a working claw, increasing the weight and complexity of the robot, invalidating part of the driver’s training, and requiring the driver to add clock management and new motor skills.
Put that in a decision matrix, estimate how many matches the negatives will cost you versus how valuable the extra points in skills will be, and decide what to do.
Or wing it. Either is good with me. Unless I’m your mentor.
Hmm. I looked at the pictures and your post. So, you’re not clearing the field in skills, which was my opening premise in the previous post. And in a tossing match…well, that’s not where your value lies. You can push a few stars under, descore some things from far zone to near zone, then scoot to the corner and elevate.
That would make you a better alliance partner/pick than a straight pushbot. Worth considering, in this case.
The motor that we are planning to take off of our robot is the one that knocks stars off of the fence for us. We don’t * usually * knock stars off of the fence during matches. And as for skills, when we do knock stars off of the fence, we have only gotten 10 points from knocking all of the off. If we did get the hang, we would potentially be adding 2 points to our score. Plus we can add something to the lift so that we can knock stars off of the fence if we wish.
Really the only thing that would make the lift not that useful is when it is a close game. Because of the potentially long time it would take to lift, the opposing alliance would most likely be able to score 12+ point is 15-30 seconds.
This was our robot in June. It had a one motor 1:1 rack and pinion design (our Y team used two motors), and it could lift and hold all 6(ish) pounds of our robot.
Yes 1 motor lift is possible… “just because you can, doesn’t mean you should”
With only one motor, you may face some issues along with your lift, but there have been some examples that have worked to different degrees of success.
Earlier in the year we had a one motor high hang similar to 333x but our robot weighed 20 pounds and could high hang in 4 seconds with one to 15 gear ratio and one high strength motor
