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robogeek753
05-01-2008, 21:34
I am considering using a stationary electromagnet (of course, insulated and under circuit breakers etc.).

All it will be doing is moving another magnet, in a very controlled way (the other magnets motion will be restricted).

The rules state that no motors, servos, or electronic solenoid actuators other than those in the KoP may be used.

To me, both motors and servos spin, so what I am considering isn't either of those. And when I looked up what an electronic solenoid actuator was, It also didn't fit what I was doing. (They involve springs and valves and such).

Does anyone know a reason this application wouldn't be legal? Too bad the Q&A forums aren't up yet :(

P.S. It would also be under a Victor speed controller (although it would be used as a voltage controller).

Kevin Sevcik
05-01-2008, 21:45
That mostly sounds like a solenoid to me. They have a iron core that retracts when voltage is applied to an electromagnet coil. At any rate, you should pay attention to <R59> not <R60> 59 tells you exactly what you're allowed to use. 60 lists a few things you most definitely can't, but you can't really expect the GDC to list every single kind of actuator they don't want you to use. I mean, they don't mention voice coils, ultrasonic actuators, electric clutches, magnetorheological shocks.....

gburlison
05-01-2008, 22:05
If you are willing to believe Wikipedia,
"An electric motor uses electrical energy to produce mechanical energy"
"Most electric motors work by electromagnetism,................Most magnetic motors are rotary, but linear motors also exist"

So you cannot use an electro magnet to produce mechanical energy as that would be an electric motor.

robogeek753
05-01-2008, 22:07
I agree that R59 doesn't specifically allow an electromagnet, however, unless my application of one would be considered an electric solenoid actuator, it doesn't seem like R60 disqualifies its use. What would define an electric solenoid actuator?

robogeek753
05-01-2008, 22:12
If you are willing to believe Wikipedia,
"An electric motor uses electrical energy to produce mechanical energy"
"Most electric motors work by electromagnetism,................Most magnetic motors are rotary, but linear motors also exist"

So you cannot use an electro magnet to produce mechanical energy as that would be an electric motor.
So do you believe my application (linearly moving another magnet via magnetic fields) constitutes a linear motor?

ahecht
05-01-2008, 22:29
A solenoid is defined as a current-carrying coil of wire that acts like a magnet when a current passes through it. An actuator is defined as a device responsible for actuating a mechanical device. Therefore a solenoid actuator is something actuates a mechanical device using a solenoid, which is exactly what you are describing.

Gary Dillard
05-01-2008, 22:36
As I recall (I don't see anything specifically addressing your question in the rules), in past years magnets have been considered a violation of rule R01, since they have energy stored at the beginning of the match in a manner which is not allowed by this rule. So even if the electromagnet were allowed, the other magnet wouldn't be.

Kevin Sevcik
05-01-2008, 22:36
I agree that R59 doesn't specifically allow an electromagnet, however, unless my application of one would be considered an electric solenoid actuator, it doesn't seem like R60 disqualifies its use. What would define an electric solenoid actuator?You misunderstand me. <R59> tells you exactly and only what electric actuators it is legal for you to use on the robot. If it is electrical, it moves something, and it's not in <R59> then it won't be legal. <R60> is only a list of some examples of things that are illegal. As i said, the GDC doesn't have the bytes to waste listing every single thing that is illegal to use.

If you want specific, painstaking reasoning, then look at the part use flow chart at the end of the robot section. An electromagnet is an electronic component. After that, if it's an "other actuator" which I believe as it's moving something, then the question is if it's a legal extra motor or servo. It's not in <R60> so it's not legal.

If you maintain that it's NOT an actuator, then it's an additional electronics component. I refer you to:<R81> The use of additional electronics (beyond those provided in the Kit Of Parts) is permitted to allow teams to construct custom circuits for their ROBOTS. Custom circuits may be used to indirectly affect the robot outputs by providing enhanced sensor feedback to the Robot Controller to allow it to more effectively decide how to control the ROBOT.If your electromagnet coil isn't sensing but actually moving something, then it's not legal.

I'm sure it's a very cool idea, but it's just not a legal part on an FRC robot.