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
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?
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)
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
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.
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?
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...
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.