homemade speed controlllers (for school project)

[Denman]

sorry, i dont care about whether its legal, but it could be a project for my electronics coursework, and i could test it on an old robot if i built it. Maybe i wont, i'm just interested in whether anyone has and if so how hard is it to do?

[Mike Betts]

Stephen,

Power electronics is a fascinating subject. Yes, with some coaching and some hard work on your part, I think you could do it. Please PM me when you plan to start and we will start a new thread here. However, can we wait until after next week? I'm swamped right now...

Mike

[Katie Reynolds]

Originally Posted by Denman

Its legal, but you have to get it approved by FIRST.

It's false statements like this that get other teams in trouble.

Originally Posted by Denman

sorry, i dont care about whether its legal

Regardless, you shouldn't go around making a statement like the former; especially when it is explicitly stated in the rules that only Victor 884 speed controllers may be used.

<R22> Only Victor 884 Speed Controllers are permitted. Victor 883 and 885 Speed Controllers may not be used.

[Denman]

Originally Posted by Katie Reynolds

It's false statements like this that get other teams in trouble.

Regardless, you shouldn't go around making a statement like the former; especially when it is explicitly stated in the rules that only Victor 884 speed controllers may be used.

<R22> Only Victor 884 Speed Controllers are permitted. Victor 883 and 885 Speed Controllers may not be used.

sorry i've changed the original post now...

[Justin_302]

Originally Posted by Katie Reynolds

It's false statements like this that get other teams in trouble.

Regardless, you shouldn't go around making a statement like the former; especially when it is explicitly stated in the rules that only Victor 884 speed controllers may be used.

<R22> Only Victor 884 Speed Controllers are permitted. Victor 883 and 885 Speed Controllers may not be used.

he is asking how you can make one. he doesnt want to use it for Compitition

[sanddrag]

Back on track...

Does it need to go forward and reverse or only forward? It is pretty easy to make a forward only one actually.

[Denman]

havn't decided yet, it depends how hard it is to make one go backwards....
ideally yes
having im'ed mike betts, i'm probably going to be starting this in a couple of weeks (given other stuff gets sorted as well...) and there will m/p be a thread about it then

[Denman]

Originally Posted by Denman

havn't decided yet, it depends how hard it is to make one go backwards....
ideally yes
having im'ed mike betts, i'm probably going to be starting this in a couple of weeks (given other stuff gets sorted as well...) and there will m/p be a thread about it then

i saw a couple of weeks
i mean a few weeks more from now.... seem to have got overloaded with other stuff ...

[greencactus3]

if you know how to use a servo, and understand the concept of resistors and how to read the lines you can make a clumsy mechanical real easy.

[sanddrag]

Originally Posted by greencactus3

if you know how to use a servo, and understand the concept of resistors and how to read the lines you can make a clumsy mechanical real easy.

The problem with that is that you are not pulsing electricity, you are converting electricity into heat. The lower the voltage (speed) the higher the heat. You are making a constant power draw. The difference is the ratio of heat energy to kinetic energy.

So what I'm basically sayingis generally speaking a mechanical speed control will run down the battery faster than an electronic one, and it will get very hot. Electronic is better.

[greencactus3]

So what I'm basically sayingis generally speaking a mechanical speed control will run down the battery faster than an electronic one, and it will get very hot. Electronic is better.[/quote]
yea i know but its so simple. not sure he said he was going to use a battery actually. if its unlimited power supply and littel heat isnt a problem id just make a mechanical.

[Katie Reynolds]

Originally Posted by Justin_302

are you that stupid? he is asking how you can make one. he doesnt want to use it for compition

Hey now, no need to insult. I realize what he is asking; I posted the rule from the handbook to verify that the statement "Its legal, but you have to get it approved by FIRST." is indeed false. I posted it so someone reading this thread would not mistake his original statement as true, to avoid further confusion, and to make sure those skimming over the thread were fully aware that you cannot use homemade speed controllers in the FIRST robotics competition.

[Denman]

yes, hence why i edited the original post to remove the confusion. I thought you used to be able to do it and hence you still could, but i'm wrong and i accept that