Digital Sidecar relay ports: correct voltage?

[Gary Bonner]

This Q&A more closely describes what we are doing with the electromagnet:

http://forums.usfirst.org/showthread.php?t=14279

[PhilBot]

Originally Posted by Gary Bonner

This Q&A more closely describes what we are doing with the electromagnet:

http://forums.usfirst.org/showthread.php?t=14279

Yes, that's much more definative. Glad you found/received a clearer answer.

[Ether]

Originally Posted by PhilBot

Wow, that's a pretty broad interpretation.
Electromagnets good, Solenoid Actuators Bad.

It's actually a narrow interpretation. A COTS electromagnet is clearly permitted as long as it is not actuating something. A COTS electro-magnetic actuator is not permitted under any circumstances.

Make sure you have a printout of that Q&A on hand at all times

I just hope you don't get a finicky EE as an inspector.
There could be some big arguments there......

The only thing that is not clear is whether a COTS electromagnet is permitted if it is actuating (forcibly moving) something external to itself on the robot. That specific question has not been explicitly addressed by GDC by either of the Q&A responses, since both questions were asking about an electromagnet simply holding something, not moving something.

There have been no arguments about electromagnets used as a holding device, that I am aware of. I don't expect any. The GDC ruling was quite unambiguous.


~

[PhilBot]

I'm not arguing the ruling... but if you really want to split hairs, how is holding something, and then letting go, NOT an actuator.

What is the purest definition of an "Actuator"?

Seriously, unless you are using the magnetic field to manipulate sub-atomic particles, isn't the whole point to effect the motion of another item... holding, or pushing, or pulling.... in all cases you are excerting a force on another object, causing it to either move, or not move. In the case under siscussion, if the electromagnet is on amd the metal is being "held" in place, and then some external force (robot) did pull the metal away from it, and then than force was removed, wouldn't the electromagnet pull the metal back into place again... So although it would "normally" be holding it in place it may actually move it under some unforseen operating circumstances.

So... holding or pulling or pushing.... seems to me it's an actuator no matter what it's doing. Fortunately the GDC has ruled otherwise... but it's far from "unambiguous" in my more "generic" view.

Originally Posted by Ether

It's actually a narrow interpretation. A COTS electromagnet is clearly permitted as long as it is not actuating something. A COTS electro-magnetic actuator is not permitted under any circumstances.

The only thing that is not clear is whether a COTS electromagnet is permitted if it is actuating (forcibly moving) something external to itself on the robot. That specific question has not been explicitly addressed by GDC by either of the Q&A responses, since both questions were asking about an electromagnet simply holding something, not moving something.

There have been no arguments about electromagnets used as a holding device, that I am aware of. I don't expect any. The GDC ruling was quite unambiguous.

~

[Ether]

I'm not arguing the ruling... but if you really want to split hairs,

I don't want to split hairs.

how is holding something, and then letting go, NOT an actuator.

Just telling you what the GDC ruling is. The ruling was clearly that if you are using a COTS electromagnet to just hold something, and then let it go, it is legal. That much is quite clear. If you want to call that an actuator, I don't mind.

What is the purest definition of an "Actuator"?

Seriously, unless you are using the magnetic field to manipulate sub-atomic particles, isn't the whole point to effect the motion of another item... holding, or pushing, or pulling.... in all cases you are excerting a force on another object, causing it to either move, or not move. In the case under siscussion, if the electromagnet is on amd the metal is being "held" in place, and then some external force (robot) did pull the metal away from it, and then than force was removed, wouldn't the electromagnet pull the metal back into place again... So although it would "normally" be holding it in place it may actually move it under some unforseen operating circumstances.

So... holding or pulling or pushing.... seems to me it's an actuator no matter what it's doing.

You may call it an actuator if you like. But other people may misunderstand you.

Fortunately the GDC has ruled otherwise... but it's far from "unambiguous" in my more "generic" view.

The GDC ruling is clear as far as how they have specifically permitted electromagnets to be used. Whether or not it is permitted to use an electromagnet in different contexts is a different question, as yet unresolved AFAIK.


~