Robot Arm C

[Jim_R]

Discussion for Robot Arm C.

Robot Arm Wiki
2011 Thread

[sachleen]

This robotic gripper uses coffee grounds in a balloon and a vacuum to pick up objects of any size or shape. I would really like to see somebody implement this in their device. It'll be slow, but still very neat and looks fairly easy to build. How strong are battery those powered vacuums?

[Flavorflav]

This robotic gripper uses coffee grounds in a balloon and a vacuum to pick up objects of any size or shape. I would really like to see somebody implement this in their device. It'll be slow, but still very neat and looks fairly easy to build. How strong are battery those powered vacuums?

That is really, really cool.

[illusionist]

Wow, that's a beautiful piece of engineering...

[blazer]

I keep calculating a maximum score of 93, not 94. Am I missing something?

[chalker7]

Correct me if I am wrong, but I can only calculate a maximum score of 93, not 94 as the rules say. My suspicion is the trial rules were double corrected as the maximum score was raised by one point and the following rule was removed: d. At the end of the run, any item that is completely within the North Zone and not completely supported by one of the Goal Boxes will receive 1 point. Without the 4th D battery scoring one point, the maximum score is 93.

In my printed copy of the rules 7.d is still there, which would still make 94 the maximum number of points available (due to the final D battery sitting on the ground in the North Zone). Is your copy different?

[blazer]

My copy is the same. I guess I just missed it. How many motors do you think the national-winning arm will have?

[chalker7]

It is . I guess I just missed it. How many motors do you think the national-winning arm will have?

Wait, it is different? I'm confused.

I'm expecting the nationals winners to have either 3 or 4 motors.

[harryk]

I have an idea for an arm with a single motor; using a complex transmission to direct power to different joints, though I think this would prove to be slow, clunky, fragile, and hard to operate, so you probably wouldn't get full points and the advantage of having one motor wouldn't be reaped

[blazer]

Rule 7d is included.

I have an idea for an arm with a single motor; using a complex transmission to direct power to different joints, though I think this would prove to be slow, clunky, fragile, and hard to operate, so you probably wouldn't get full points and the advantage of having one motor wouldn't be reaped

Wouldn't you need a second motor to control the transmission?

[illusionist]

I don not have the rules yet, so are we allowed to use autonomous robots, or is it human-electronic control only?

[harryk]

Rule 7d is included.

I have an idea for an arm with a single motor; using a complex transmission to direct power to different joints, though I think this would prove to be slow, clunky, fragile, and hard to operate, so you probably wouldn't get full points and the advantage of having one motor wouldn't be reaped

Wouldn't you need a second motor to control the transmission?

You manually control the transmission, as far as I know it should be legal since you're not actually powering the arm, only controlling it

[28]

what factor will time play in the scoring/tie brakers?

[sachleen]

I have an idea for an arm with a single motor; using a complex transmission to direct power to different joints, though I think this would prove to be slow, clunky, fragile, and hard to operate, so you probably wouldn't get full points and the advantage of having one motor wouldn't be reaped

Wouldn't it always move in the same way every time? Meaning, it would extend forward the same amount as it goes down, and back as it goes up. I fail to see how a single motor could be used to make the arm move in different ways.

[twototwenty]

harryk's idea might work if there were two motors, one to power the whole arm and one to switch which piece of the arm the motor was controlling. But to make this type of arm work at all you would need a very high power motor to power the whole arm from one place ( not to metion a very well engineered gear system), and this type of motor would not have enough voltage due to the voltage limits for the competition (unless these limits have been very significantly changed, as I don't ahve the oficial rules yet).