recommend me a barebones robotic arm kit

samcheetah

New Member

• Jul 4, 2005

• #1

hiya everybody

i searched on the internet for a good robotic arm kit but i found out that most of them were wayyyy expensive. about all of them had a microcontroller or a PC interface with a good looking software. but then i thought, what the heck!!! i can do the controlling part myself with a PIC microcontroller. so would someone help me find a robotic arm kit which only has the mechanical assembly and motors. ill do the rest myself

 

samcheetah

New Member

• Jul 6, 2005

• #2

wow not a single reply :shock:

anyway i have the above stated problem sorted out (well, sort of)

now the main problem is that RC servo motors are really expensive and i can get lots of stepper motors for dirt cheap prices. but positioning with stepper motors is not absolute so what should i go for?

 

P

pittuck

New Member

• Jul 6, 2005

• #3

go to ur local model shop and see if they have anything cheaper. I got my 'standard' servo's for £4 each (well only after blowing one up (litterally) and going out to seek replacements)

 

samcheetah

New Member

• Jul 6, 2005

• #4

i have gone to a local model shop and the cheapest mini servo they have is for Rs. 700 (thats about 7 pound sterlings) and the Hitech mini servo that i liked while surfing on the internet is Rs. 1450. standard size servos are more expensive

i know that the price is not that much but i need at least one mini servo and 5 standard size servos.

what do you guys say about using a stepper instead of a servo

 

Kingpin094

New Member

• Jul 6, 2005

• #5

Don't know how much is too mcuh but lynxmotion.com has a 5 axis kit for
around $170. Kit comes with all the mechanicals and the servos.

**broken link removed**

I have bought a couple of there kits and they are really nice.

They also have a 6 axis kit for a little more.

Hope that helps.

 

Nigel Goodwin

Super Moderator

Most Helpful Member

• Jul 6, 2005

• #6

samcheetah said:

what do you guys say about using a stepper instead of a servo

Click to expand...

It all depends if you can provide a suitable absolute feedback system,?, if you can connect a potentiometer in some way (rather like a servo), that would be fine.

 

samcheetah

New Member

• Jul 6, 2005

• #7

actually Kingpin094 my design is resembles the Lynx5 alot. but the reason i cant order the kit is that (1) the freight charges for my country are usually very high and the custom clearance for such an item would be a real pain (2) the instructor who has told me to make a robotic arm says that you shouldnt buy a premade kit.

so im stuck with milling and machining the mechanical assembly myself (ofcourse i will need help from others).

and Nigel resistive feedback isnt that much accurate. so how about the idea of a home switch?

 

williB

New Member

• Jul 6, 2005

• #8

sam ,i did not see your post..
a home switch is not all you would need if you go with a stepper , because what if the stepper skips, due to loading, you will need an accurate optical position sensor, as well as your home switch..
what about making your own DC servo , there must be some old copiers lying around , they have great parts in them, like DC/AC motors some even have position sensors on them...

 

samcheetah

New Member

• Jul 6, 2005

• #9

thanx for your reply williB

i found the following project at the DPRG website

**broken link removed**

so if i make an optical encoder as the one in the project and add a home position switch, will i be able to accurately position the stepper.

i think there will be lots of calibration involved for the positioning mechanism. and there is one other concern, i have to get the Hamamatsu P5587 IR emitter/detector that is used in the project. i hope i do get it from somewhere.

and ill also see if i can get some motors out of a copier.