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View Full Version : Where can i purchase RC servos



bhatia
04-18-2006, 09:57 AM
Hi i m workin on development of an autonomous mobile robo, i ve choosen hexapod as my first project, but i need to purchase servo motors and also BDMICRO board for programmin , can u please tell me where can i buy rc servos (like hitec-422 standard servo) in india near punjab and related components ?


Shashank Bhatia

bhatia
04-18-2006, 12:34 PM
Hey at lease let me know where can i purchase servos from ? Ant type of servo motor will do if not Hitec servos.

taknev13
04-18-2006, 08:23 PM
if its just the hexapod why do u need the servos? go for plain simple geared dc motors.

geared dc motors will usually cost u abt 200-300 rs. with awesome torque

whereas a servo will cost u anywer abt 1100 to 1400

you can get both of them at a company called ROBONENCE in bangalore.

they will even ship it to punjab.

thier contact info is 080-41526083 talk to mr suraj

docel
04-18-2006, 08:51 PM
bhatia wrote:

Hey at lease let me know where can i purchase servos from ? Ant type of servo motor will do if not Hitec servos.

Instead of screaming , why dont you search ?
There are plenty of posts with advice, pointers and addresses. Dont expect others to run and do your work for you. [/u]

I have some Hitec servos @ 1800/- per piece : pm me with DD!

bhatia
04-19-2006, 11:51 AM
taknev wrote :


if its just the hexapod why do u need the servos? go for plain simple geared dc motors.


Taknev, i m building a hexapod with 3 DOF, now for that i think i hav to go for servos only. I kno one mechanical arrangement using which i can make the hexapod move using only one simple dc motor. But the problem is i dont know hw will i make it take a turn.

Please do suggest me what can be done to make it turn.

Thanx
Shashank Bhatia

bhatia
04-19-2006, 11:54 AM
docel wrote :


nstead of screaming , why dont you search ?

I hav been searching from last 5 days, i hav got plenty of links and addresses, i was just trying to find out if i can get them near Punjab.

thanx for ur advice 8O

Shashank Bhatia

taknev13
04-19-2006, 12:35 PM
hey bhatia,

c ill tell u the basic difference between servos n dc geared dc ie servos have feedback n dc geared dont have rest everythng is same between them.so ii dont understand how will a 3 dof effect the motors u are using .even the servos can only give 1 dof. for 3 dof ur design will change not the motors.

and for a thng like hexapod i thnk go ahead n look for designs on hexapod ull find plenty,n come back n implement that design iwith cheaper motors instead of using servos coz servos arent required in projects where u dont need accurate precision n automated motions.

thats my suggestion rest is up to u

bhatia
04-19-2006, 01:02 PM
Thanx tacknev for ur valuable suggestion. Sure hexapod is not such a high percision machine. But can we use PWM signals to control a normal dc motor .
IN other words , can we use normal dc motor for controlled motion ?
I hav an impression that servos are used where u need to hav position control.

i kno hw servo works and also the difference bw a servo and a normal dc motor and even a stepper. But now i need to know hw can i use a normal
dc motor for a controlled motion.

Please help me.
Thanx
Shashank Bhatia

taknev13
04-19-2006, 06:15 PM
k lets get some points straigt befor we proceed.firstly there is a difference between geared dc and a plain dc.plain dc wont give u sufficient trque and has hi rpm n drwas a lotta current for roboticc application.whereas geared is low rpm n has ver less current draw.

So use geared n not plain dc.

Secondly ur doubt how to use geared dc in a controlled way....

there are many of them like quadrature encoders n stuff... gooogle for em.

easiest of all is print a wheel with many holes in it.
put an ir transmitter reciever pair on either side n keep a track of the count.
so ucan control it almost like a servo except for some inaccuracy which arises some times due to mechanical problems.

but hexapod wont have dat so dc geared is always advisable.

rest i have already told u where u get dc geared so now ithe ball is in your court

bhatia
04-19-2006, 06:22 PM
Thanx taknev, i will look into the matter . I will see what can be done, i know abt the torque and the geared motors etc, infact i hav my own workshop i can develop the necessary gears or mechanical systems required. I will contact you lator and tell you about what i have done.

Shashank Bhatia

rao
04-20-2006, 11:14 AM
look at the post RI goes to Innova in that.. look for the winning team robot's clip..

that is a hexapod with just one DC MOTOR!! the total cost of that hexapod is 300/-!!

Dude it is all about how you want to take the work out of the motor..

Rao

docel
04-20-2006, 01:03 PM
...and thats because everyone wants to "copy" someone elses design and duplicate it 'identically'. Almost all Hexapods on the net are made of servos :!:
It is time that every one understood: Steppers and Servos are NOT the only components for everything. There are plenty of ways to do the same thing. You dont even need to make a gear-box for a hexapod!!!

Bhatia, you are lucky to have a machine shop of your own: This is an oppertunity for you to create something different and innovative!A robo with servos and Futaba remotes, people will just nod. A robo with a DC motor and autonomous? People will stand up and stare!!

Just go at it and create something you can call your own and reap the appreciations and credits. Man, that feeling of pride and satisfaction is something you have to experience for yourself.

Good luck!

bhatia
04-22-2006, 12:47 PM
Now that's something i ve not thought about till now. I think what u r saying is ablsolutely correct. And in my workshop, i hav complete set of tools and ideas available for designing a hexapod movements. I had some doubts about how 2 make the hexapod turn. I think wid little more work i can find out a way. Thanx for the guidance and help. I will keep u informed about what i m designing and builduing.

Thanx
Shashank Bhatia

vikas
04-23-2006, 02:48 AM
Since youve been enlightened might be of little use ...

Any how try http://www.indiarc.com/store/servos.htm