[Robotgroup] MOTORtHrEAD

[Robert Carter]

Hi everybody-- thanks for all the answers to the questions I posted  
on Friday.

As we start to gear up for BS SIG round II, I'm starting to move  
beyond the exercises outlined in the course book, and to look at how  
to build my own circuits for the minigolf project. At the meeting on  
4/24 I brought in a motor that I had extracted from a $20 Harbor  
Freight 18V cordless drill. My goal is to create a BS circuit that 1.  
accepts an input trigger, 2. spins the motor counter-clockwise for 3  
seconds, 3.pauses for 8 seconds and then 4. spins the motor clockwise  
for 3 seconds. The epitome of simplicity. Good place to start.

So now I'm trying to learn what I can about diodes and transistors to  
build the bridge. Right now I'm in Denver (conference and family  
visit), about to head to the airport to fly back to Austin. I've  
pulled up some pages from the allaboutcircuits.com website that Andre  
recommended (thanks Andre) to read while waiting at the airport, I  
expect tomorrow I'll have some more questions for the group.

Regards--
Robert



On May 2, 2008, at 6:02 PM, Robert Carter wrote:
> Hey y'all--
>
> I feel kinda proud of myself that I was able to follow most of the
> thread on RC motor controllers without being completely lost. While
> reading, I started keeping a list of terms/phrases I didn't
> understand. Here's the list; if anyone would like to fill in some of
> the blanks for me, that'd be great.
>
> ·      PWM (example: "… but you can drive 5A with PWM 80% duty  
> cycle…")
> ·      Transient currents
> ·      Overclock ("…you can run it at 6V and run it faster and
> overclock it as well.")
> ·      Locked rotor amp ("…you pretty much need to have a motor
> controller rated for the locked motor amps of the motor you are going
> to use." )
>
> That last one, I think I understand what it means from the context,
> but when I tried to put it in my own words I couldn't come up with
> anything that makes sense, so I'm curious to hear how someone might
> explain it to an inquisitive 9-year old.
>
> I've got more questions specific to what I'm trying to do with my
> project, but let's start with these. BTW, has there ever been talk
> about creating a glossary page on the wiki for stuff like this? Or
> are there already a lot of good ones out there, that I just don't
> know about?
>
> Thanks--
>
> Robert
>
>
> On May 2, 2008, at 2:04 PM, brooksdesign wrote:
>
>>
>>  Allthough I think there are programs out there that I've heard of
>> you just made public one of the parts of a new video game I've be
>> contemplating. And in saying that and letting that cat out of the
>> bag, any of you game programmer guys want to come out and talk
>> about how to turn my scripts, cad files and ideas into something
>> real that I won't leave sitting on the shelf because I can't get
>> around to learning to write code? This project is waay more than a
>> game.
>> -brooks
>> -----Original Message-----
>>> From: Robert Carter <rcarter at ischool.utexas.edu>
>>> Sent: May 2, 2008 2:24 PM
>>> To: The Robot Group Mailing List <robotgroup at puremagic.com>
>>> Subject: [Robotgroup] MOTORtHrEAD
>>>
>>> <clip>
>>> The nice thing about electronics is that physics is the final
>>> judge of
>>> your choices.
>>>
>>> You can get people to "vote" for various approaches, but even if
>>> all of
>>> us voted for item "A" (placing a fuse in parallel with the motor
>>> controller) that wouldn't make one whit of difference to the  
>>> circuit.
>>> </clip>
>>>
>>> Hell yeah, that's my way of learning: forge ahead with crazy ideas,
>>> and learn from the consequences. If nothing else, you'll get some
>>> good stories. Like when my brother and his best friends discovered
>>> the formula for gunpowder and started a fireworks shop in the attic
>>> over our garage. But, when it comes to electronics, I have to admit,
>>> it gets expensive and time-consuming to have to keep running back to
>>> the store or to the internet for replacement parts when something
>>> explodes/melts/starts to smoke.
>>>
>>> I keep hoping that someone will invent an interactive website for
>>> designing circuits, aimed for grade school students and/or middle-
>>> aged project addicts with more enthusiasm than sense (like yours
>>> truly). You could drag and drop motors of various amperage, LEDs,
>>> transistors, capacitors, etc. onto a virtual breadboard to create a
>>> circuit. If it works, you get the results in animation form: the
>>> motor spins, the lights blink, etc. Or conversely, if you design it
>>> badly, you can show the sparks and smoke as your components burn  
>>> to a
>>> crisp. Fun, inexpensive, and no one gets hurt.
>>>
>>> Usually when I think of something and it seems like a really good
>>> idea, something like it already exists. Does anyone know?
>>>
>>>
>>>
>>> Robert Carter
>>> Visual Resources Collection
>>> School of Architecture
>>> The University of Texas at Austin
>>> rcarter at ischool.utexas.edu
>>>
>>>
>>>
>>> _______________________________________________
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>>> Robotgroup at puremagic.com
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>>
>>
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>
> Robert Carter
> Visual Resources Collection
> School of Architecture
> The University of Texas at Austin
> rcarter at ischool.utexas.edu
>
>
>
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Robert Carter
Visual Resources Collection
School of Architecture
The University of Texas at Austin
rcarter at ischool.utexas.edu