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rohanpatil
02-03-2009, 11:45 PM
Hi! I am a new user! I am a n00b in electronics!
My friends and I are Computer Science students.. :?
We are using stepper motors to control the camera's azimuth and elevation..
for that we are using
the following equipment!

1) Overo Earth ==> http://www.gumstix.net/Hardware/view/Hardware-Specifications/Overo-Specifications/112.html
2) summit an expansion board for overo earth ==> http://www.gumstix.net/Hardware/view/Expansion-boards/Overo-Expansion-boards/112.html

Which stepper motor kit should i use? please specify which are available in india...

There are signals in the summit boards
Signals
(Available on 0.100" through-holes at 1.8V logic)

can these be used to control the stepper motor??

Please bear with my n00bness !!
:oops:

rohanpatil
02-04-2009, 12:31 AM
Hi! I am a new user! I am a n00b in electronics!
My friends and I are Computer Science students.. :?
We are using stepper motors to control the camera's azimuth and elevation..
for that we are using
the following equipment!

1) Overo Earth ==> http://www.gumstix.net/Hardware/view/Hardware-Specifications/Overo-Specifications/112.html
2) summit an expansion board for overo earth ==> http://www.gumstix.net/Hardware/view/Expansion-boards/Overo-Expansion-boards/112.html

Which stepper motor kit should i use? please specify which are available in india...

There are signals in the summit boards
Signals
(Available on 0.100" through-holes at 1.8V logic)

can these be used to control the stepper motor??

Please bear with my n00bness !!
:oops:

I actually found these stepper motors! ==> http://robokits.co.in/shop/index.php?main_page=product_info&cPath=2_4&products_id=139

And these controllers for them ==> http://robokits.co.in/shop/index.php?main_page=product_info&cPath=1&products_id=15

will this driver accept the input from the 1.8v signals from the summit ??? but it says : "Upon giving the battery/power supply to circuit it will drive the motors as per the input from RC circuit / Microcontroller / PC output or any other circuit that gives 3-5 V output. " I dont know if summit gives 3-5 V output !! :?

vikas
02-04-2009, 11:19 AM
You will need gearing also.

What exactly is the objective here , cant you use ITX boards ... they are cheaper and way more powerful.

rohanpatil
02-04-2009, 11:24 AM
Hi vikas!!
There is much more functionality involved..
GPS
GPRS
WiFi
and what not..
we are actually integrating all these and into a system, which gives us images with GPS information.. which are either transmitted via wifi or gprs i.e if wifi not available then send the data via gprs..
and mount this system on a RC heli.. so its gotta be as light as possible..

vikas
02-04-2009, 12:59 PM
Sounds nice but i hope you have a huge budget ( in lakhs ) !!!
Also Ever flown a RC helicopter ? it aint so easy as it looks ... they crash real easy , i have two lying with me with broken rotors and are useless.

Also to mount all this you will need a Heli which can actually carry some weight and not some cheap RC heli. Even after there are lots of things...

At your stage making a heli hover would be enough :).

From the looks of it i would recommend you to do a ground based vehicle ( For experience ) before you fly , as costs and technicality multiply exponentially when you leave the ground.

rohanpatil
02-04-2009, 02:37 PM
No budget in lakhs and all.. :D we should finish the system.. if we finish it then only we'll buy a heli and mount it.. we have zeroed in on a 50'" gasser .. we have some friends who have flown helis... so its not a problem .. i realized u have worked with gumstix.. what are the shipping costs dude?? and the answer to the above problem would be appreciated :D

vikas
02-04-2009, 04:40 PM
Its ur call , I was advising from exp. Ive worked and have done to some extent what u are trying.

Gumstix ull have to import , will cost original cost + 30 USD shipping + (25- 50 % Duty ) All in USD

So a 100 USD gum stix will cost about 150 USD after shipping and duty.

Also skip the steppers , they are heavy and not meant for this. Use mini servos instead , As your board already support PWM u just have to glue them together :) , and ull skip the whole steeper headache .

Skpi Wifi and GPRS , and try XBee for RF.

rohanpatil
02-04-2009, 05:10 PM
Sad that the customs cost so much :( .. cant they be sent as a gift or something? :D

Thank you so much for suggesting servo motors..
http://robokits.co.in/shop/index.php?main_page=product_info&cPath=2_5&products_id=189

overo's MB's can handle the operating voltage of this servo motors?
http://www.gumstix.net/Hardware/view/Motherboard-I/O/Connector-J1-for-Overo/112.html
in this site it says "The input range of the supply voltage is approximately 3.3V 4.2V" so will it suffice??

Dude is there any book to study and get over my n00bishness ?? :oops:
Actually I am not calling the shots,Our project guide, a professor in IISc is calling them :-)

Our guide insists that we use wifi and gprs .. hmm.. can convince him to drop wifi but gprs we are using because it has a huge range..

karthik_tunga
02-05-2009, 10:36 PM
hey!

I am using GPSstix along with gumstix. I have a few doubts .

1> does the GPS module continuously fetch the location and other parameters ?? or can it be called only when needed and then stopped ????
2> If the GPS module continuously fetches the data ..how can we know when the " /dev/ttyS2 " file is updated by the module ??
3> how long does the module take to find its position ? meaning how long does the module take to fetch the data ??

I hope I have made my doubts clear ... I am design a system wherein i don't need the GPS data all the time ..only when required ...( I am placing the gumstix on a moving object.)

Thank you
Karthik Tunga

rohanpatil
02-05-2009, 10:39 PM
hey!

I am using GPSstix along with gumstix. I have a few doubts .

1> does the GPS module continuously fetch the location and other parameters ?? or can it be called only when needed and then stopped ????
2> If the GPS module continuously fetches the data ..how can we know when the " /dev/ttyS2 " file is updated by the module ??
3> how long does the module take to find its position ? meaning how long does the module take to fetch the data ??

I hope I have made my doubts clear ... I am design a system wherein i don't need the GPS data all the time ..only when required ...( I am placing the gumstix on a moving object.)

Thank you
Karthik Tunga
Hello Karthik
I am doin a similar project! Wow!! what a co-incidence!! Where are u mounting the system??

firoz
02-06-2009, 12:14 AM
i designed below stepper controller for myself.
this can drive a 1.5A/phase motor like piece of cake.
i also have one based on L298+L297.it is also working nice.
both these boards take pulse and direction signal as inputs along with motor enable.
if interested drop PM

http://img13.imageshack.us/img13/4541/80651625je8.jpg (http://img13.imageshack.us/my.php?image=80651625je8.jpg)
http://img13.imageshack.us/img13/80651625je8.jpg/1/w1600.png (http://g.imageshack.us/img13/80651625je8.jpg/1/)