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Johnny-5
04-08-2007, 05:46 AM
I am wanting to build an arm... and glansed at come code for the basic ATOM, it looks too complex for a BS2... i have a BS2 lying around and was planning on using it to control the arm... what do u guys think? it would have about 5 or 6 DOF. Also would a Serial servo contoller really be be needed as the BS2 has enough I/O's.

Post Edited (Johnny-5) : 4/7/2007 9:53:44 PM GMT

Franklin
04-08-2007, 07:33 AM
Don't know, what arm are we talking about?

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- Stephen

crgwbr
04-08-2007, 09:11 AM
I would recomend the propellor instead. Also, it would help if you posted a drawing of the arm.

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Programming today is a race between software engineers striving to build bigger and better idiot-proof programs, and the Universe trying to produce bigger and better idiots. So far, the Universe is winning.

Microsoft: "You've got questions. We've got dancing paper clips."

Johnny-5
04-08-2007, 10:02 AM
the arm is going to be custom built... but will be something like this.

Franklin
04-08-2007, 01:27 PM
Looks like 6 servos. The advantage of the servo controller is you send it a position and forget it. You don't need to loop back and refresh the position until you want to change it. That allows you to use the processor for other things. If you're fairly new to stamps why not start with the propellor, it's a much more powerful chip and is cheaper also.

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- Stephen

Mike Green
04-08-2007, 01:39 PM
Johnny-5,
You could control the 5 to 6 servos directly with a Stamp, but that's about all it would be able to do. Servos require a control pulse about every 20ms with a width from a minimum of 0.5ms to a maximum of 2.5ms with many servos only responding to the 1ms to 2ms range. If you have 6 of these, that's a total time sending pulses of 15ms max. leaving a little less than 5ms to do something else (like figuring out the next position).

For a practical setup, you should probably use a separate servo controller (or a Propeller). A Stamp by itself would be fine for testing purposes and could run the arm through pre-recorded patterns stored in the EEPROM with the control program.