My team has made it to regionals, we have made a lot of changes to our robot one of which is the arm. The arm is too heavy, the code is set for it to hold. We have added rubber bands but they dont seem to be doing much, what can we do? @Foster @markIQ
I don’t do iq but in vrc we use dust off on the motors because often the motors over heat and this cool them down for a match in about 5 seconds.
A picture would help. How many motors are lifting the arm? If there is more than one are all of them set for hold?
Have you tried different angles for the rubber band placement? Sometimes moving the mounting location forward on the arm or higher on the backbone helps.
How many rubber bands are you using?
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Have you tried to increase the gear ratio?
Pictures would be great. Withough pictures i would suggest replacing the most 2wide structire with 1wide as possible, increasing the gear ratio on your arm and if you have extra motors add a second motor to the lift
If there is room, you might extend the arm past the motor and add counterweight.
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This kind of question is kind of pointless without picture. Or at least some explanation of construction, motors, ratios and weights involved
You can also use a gear ratio (geared for more torque), but it will make the arm slower.
I have three solutions that I can think of is either using a bigger gear ratio or you can extend the arm behind the pivot point and you can add some weight like flywheel weights to balance out the arm and help reduce the strain on the motor. The third one is not as practical but you could add an extra motor to have two motors powering the arm instead of one if you only used one.
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Adding weight to an IQ robot is a bad thing, since the motor are not that powerful. That is one of my personal disappointments with this year’s hero bot BYTE, it’s starting off very new roboteers with bad habits.
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There are two motors used for arm, both on hold, the robot will not lift but just stay there while it is trying to move. Yes we have tried that. We are using 2. What is the recommeded amount? @Foster
So two motors should work, you might want to look at the gearing.
I’ve seen robots with 3 rubber bands on each side. I said this a number of posts ago, moving the anchor points around can also make a difference.
Really, a picture would help. I know you want to keep your design a secret, so maybe a picture of just from the drive train up.
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@BrockIQ, whats the latest on your robot?
rubber band the arm up. just look at many teams that have used arms in the past they all used banding.
We fixed the weight problem by redesigning a new arm. Our problem now is that the chains are not moving the arm correctly, there are chains on both side and they aren’t working.
Any chance you have access to larger sprockets for the top to increase the ratio?
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Looks like you have a 1:1 ratio and your motors are mounted at the bottom of riser. 1:1 will not have enough torque to bring the lifter full of blocks. A simple and quick option without redoing the entire structure is instead of attaching the motor directly to the axle powering the chain, make a gear box with a higher ratio and attach that to the axle powering the chain and attach the motor to the gear box. Take a look at this video. May help you will understanding how to use a gearbox to power a chain mechanism. Of course you will need your gears arranged in reverse order to give more power or torque.
I hope that helps.
Cheers.
Try using a gear ratio or a counter weight.
Counter weights are very, very seldom the right answer. OTOH, gear ratio is a winner for this particular robot.
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Did you get this working? What was the solution?