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*bump*

Ok, I think I am going to buy the hardware, and after I have done it I have some other things I can use anything I buy for.

I really have almost no experience with hardware, but this will be a good time to learn.

My question now is
A. What would be a good controller to use
would something like this be good?
http://www.robotshop.us/home/products/robot-parts/microcontrollers/arduino-microcontroller/arduino-usb-microcontroller-board.html
it looks good to me, and I also found a tutorial on using it with python: http://principialabs.com/arduino-python-4-axis-servo-control/



B. What strength servo do I need? I may only use an airsoft pistol, but it would be nice to be able to move a paintball gun too (I am going to guess that paintball guns weigh ~10 pounds or so) What does the -- oz/in statistic really mean?

I did email the person who made the turret, and he was not any help at all >.>
That micro controller looks like it should be perfect for your needs. As for servos, honestly I would just pick up some crappy old electric motors cheap off of like craiglist or something (or pull them out of old stuff laying around the house)
You might need a better power supply, as 650mA isn't all that much at 9v. You are only going to have 5.85w of power. That power supply is for small electronics projects, not powering motors.

That said, if you've got an old PC, just rip out its PSU and you will have high wattage in a variety of voltages.
Kllrnohj wrote:
You might need a better power supply, as 650mA isn't all that much at 9v. You are only going to have 5.85w of power. That power supply is for small electronics projects, not powering motors.

That said, if you've got an old PC, just rip out its PSU and you will have high wattage in a variety of voltages.


Well I kind of need to be able to plug it into the servos >.> (and the easiest way is to plug it into the power jack on the arduino board)

I will look around for something else, although I may have an adapter lying around that would work...

EDIT: I found a place where I can get everything I need, here is the list now:
Arduino usb board:
http://www.robotshop.ca/home/products/robot-parts/microcontrollers/arduino-microcontroller/arduino-usb-microcontroller-board.html

Breadboard:
http://www.robotshop.ca/home/products/robot-parts/electronics/tools/elenco-9830-breadboard.html

servos (these seem to be the best I can find for the price, 100 oz-in for 12 dollars is a lot better then most of the other servo prices)
http://www.robotshop.ca/home/products/robot-parts/motors/servo-motors/gws-servo-en/gws-standard-s03t-std-servo-motor.html


forget about the power adapter, I looked and realized I have like 5 in a box, most of them probably 2.5 mm, and I even have one that is 12v, 1.5 amps, although I need to check the size of that one >.>
[quote="Harq"]
Kllrnohj wrote:
forget about the power adapter, I looked and realized I have like 5 in a box, most of them probably 2.5 mm, and I even have one that is 12v, 1.5 amps, although I need to check the size of that one >.>


I have no idea what the power draw is on the servo, but it takes ~5-6v.

What was wrong with my old PC PSU idea? Still the best one Razz
Kllrnohj has a point there - with a PSU with green and black shorted together on the mobo power cable, you have a nice 3.3v / high-current 5v / high-current 12v power source.
KermMartian wrote:
Kllrnohj has a point there - with a PSU with green and black shorted together on the mobo power cable, you have a nice 3.3v / high-current 5v / high-current 12v power source.


I do have 2 old PSU's, but the adapters I have look like they are 2.5mm and they have the right power for my needs. The board should only have a maximum of 12 v, and these adapters have a high enough amperage to power the 3 motors

I looked and the robotshop place is in canada, so I need to buy the parts elsewhere because shipping was at least 20 dollars

I will get the breadboard and microcontroller from sparkfun and for the motors I am still hunting for better deals and good torque.


I am looking at ebay for the servos, and there are some really good deals. I am basically looking at getting 2 servos from ebay for now, for a total of 20 dollars (they are really high torque ones and have metal gears) the cost is actually 5 dollars + 15 dollar shipping from china >.>

I checked and the price for ONE of the motors is usually 35 dollars. They have a massive number of listings of the same thing, so I have plenty of chances to buy them >.>
http://cgi.ebay.com/2-x-MG995-Hi-Speed-Torque-Metal-Gear-RC-Servo-Horns_W0QQitemZ260263927823QQihZ016QQcategoryZ34056QQssPageNameZWDVWQQrdZ1QQcmdZViewItem
Do you realize you have the same emoticon at the end of four out of five paragraphs? Razz You're killing that emoticon.

I've had some quite good luck with Sparkfun lately, first with the thread for my dataglove, then with some parts, especially an RFID reader, for my summer research project.
KermMartian wrote:
Do you realize you have the same emoticon at the end of four out of five paragraphs? Razz You're killing that emoticon.

I've had some quite good luck with Sparkfun lately, first with the thread for my dataglove, then with some parts, especially an RFID reader, for my summer research project.


That is probably because each of those was written at a different time =P

Do you have any thoughts on the ebay motors?
I don't know if anyone's mentioned this, but there are tools you can use to generate python bindings for C libraries
elfprince13 wrote:
I don't know if anyone's mentioned this, but there are tools you can use to generate python bindings for C libraries


yeah, like Swig and ctypes? There are binding of both of those for OpenCV, but it doesn't change the fact that the bloblib is A. not included by default in OpenCV and B. has almost no documentation at all >.>

It was easier to just write my own using a floodfill strategy Smile
So all of my supplies have arrived that I need for a simple laserpointer turret, but there is a problem with python.


I am using a guide ( http://principialabs.com/arduino-python-4-axis-servo-control/ ) and the included code. I have downloaded and installed pyserial, but when the code imports serial, it crashes with this error:


Code:
import servo
Traceback (most recent call last):
  File "<pyshell#2>", line 1, in <module>
    import servo
  File "C:\Python25\lib\servo.py", line 17, in <module>
    import serial
  File "C:\Python25\Lib\site-packages\serial\__init__.py", line 18, in <module>
    from serialwin32 import *
  File "C:\Python25\Lib\site-packages\serial\serialwin32.py", line 9, in <module>
    import win32file  # The base COM port and file IO functions.
ImportError: No module named win32file


What is wrong with win32file? I cannot find anything on google.
You need to install this: http://sourceforge.net/projects/pywin32/

At least, as far as I can tell you do. Hope that helps Smile
So I have both of the servo motors working, and now I need to build a simple (and cheap) turret to just point a laserpointer.

Does anyone have any really simple ideas that I can make without many tools? I am thinking of just building one out of two strips of aluminum to attach the servos to (and something to stabilize it).

If I get this working I am thinking of adding a feature to control it via wiimote =P [http://code.google.com/p/pywiimote/]
  
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