I think innoation first should make a counterweight set that includes counterweights with 5 different weights, instead of having to ues a wheel or a battery
try packing nuts and bolts into a antislip matt, and closing it with zip ties. Then attach anywhere on the robot with zip ties.
hmm…never thought of that, should work well:D
If you use a higher gear ratio, you shouldn’t need counterweights. Remember speed and torque are directly proportional.
More speed less torque. More torque, less speed.
I’ve lifted over three pounds on a one foot long arm. It moves slow, but it moves. You may need two stages of gear reduction, too.
Sometimes counterweights are used to move the centre of gravity over the supply polygon. This prevents an arm from tipping the robot over.
Yes, but with passive assitance (counter-weight, rubber-bands, etc) you can lift the SAME load at a faster speed. The passive-assistance will reduce the amount of load applied to the motor, which allows it to run at a higher RPM. Alternately, this means you can gear it a little bit faster.
In FRC, we use surgical tubing to balance out the weight of our arm. When you disconnect the gearbox the arm “floats” almost as if it was in a zero-gravity environment. The result of this? The motor only needs to lift the weight of the game object, which results in it running at a VERY low load condition. (In this case, our gripper weighed about 10 lbs, and the game object weighed about 1 lb… neutilizing the weight of the gripper was important.)
Alternately for heavier objects, you can “over-support” the arm. In this case, the passive assistance is MORE than the weight of the arm itself. When left alone, the arm will try to raise up. This means that part of the weight of the game object is neutilized. The bad part? The gearbox sometimes needs to work to “pull” the arm down, instead of working to “lift” the arm up. There is a tradeoff to be made in this type of design.
Passive Assistance is a wonderful thing.
Regards,
John
We tried that on a robot but the motor spasmed out more than normal:p
Define Spasmed.
We used rubber band to pull down on the arm. ok like the arm would just all of a sudden go all the way back to where it starts to bend metal:D 
Before we put the rubber band on it was fine for the most part
none of this helps. any other ideas? (;
1 Like
This post was originally made 12 years ago. It would have been more beneficial to start a new topic.
I’ve seen teams just take stacks of metal plates to counteract any tipping. Those are the densest you can get.
2 Likes