servo board

Hi i got a arm development board with serial port and ethernet. I want to control 6 to 10 servos by serial/ethernet port. Where i can buy such thing? i need a complete solution (plug and play), because i don't have any knowledge on electric, i am a programmer. thanks from Peter ( snipped-for-privacy@hotmail.com)

Reply to
cmk128
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JM

Reply to
John Mianowski

John Mianowski =E5=AF=AB=E9=81=93=EF=BC=9A

really cool and thanks. But is there any thing can control the "contingous servo"? i am using a "continugous servo" for the wheels. thanks from Peter

Reply to
cmk128

The servo control board doesn't know the difference. The software you write will be simpler, as you know have only three modes for any motor:

  1. Send 2 millisecond duration pulses every 20 milliseconds to go one direction;
  2. Send 1 millisecond duration pulses every 20 milliseconds to go the other direction;
  3. Don't send any pulses, and the motor will stop.

-- Gordon

Reply to
Gordon McComb

Some serial servo controllers beyond the mini ssc-II.

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Reply to
Si Ballenger

Peter,

As Gordon said, the continuous servos receive the exact same signal as the normal server. The difference is that it interprets the position information as speed information. A signal which makes a normal server move to the center position is seen as a 0 speed for the continuous servo. Positions on either side of that cause it to spin forward, or backwards, at different speeds. So any servo controller board will work fine for both types of servos. The commands simply translate to speed commands instead of position commands.

With the Mini SSC II board (the first suggestion posted) you can't make it stop sending pulses. So you don't have a simple way with that board to guarantee your servo is not moving. If you set the center position with your software, it should stand still, but this is not perfect because it's an analog pulse width protocol that the board using to control the servos, and the pulse width generated by the servo board for the center position might not be the exact width needed to make it stand still. So it's likely to cause the servo to creep slowly.

Some of the more advanced boards posted in that second message give you the ability to tell the controller to turn the servo off - which means it just stops sending pulses as Gordon talked about above. For controlling continuous spinning servos, it would be good to get a board that allowed you to stop sending pulses to the servo. That can be a useful advantage for normal servos as well because when you stop sending pulses to them, they stop holding their position and can be moved to a different position (though because of gearing it takes a bit of torque to move them).

Reply to
Curt Welch

Curt Welch =E5=AF=AB=E9=81=93=EF=BC=9A

thank you so much to teaching the newbie (me). I am going to develop an AI using my arm 7 development board to let the robot walk by two legs. Is anybody here is doing the same thing? I need to make a "expand and contract" servo, which like the "oil presure servo" works. i really can't find a tutorial website in google, do you know any? thanks from Peter

Reply to
cmk128

snipped-for-privacy@hotmail.com =E5=AF=AB=E9=81=93=EF=BC=9A

Hi all do you have any website that talk about "very flexible movement" robot? thanks from Peter ( snipped-for-privacy@hotmail.com)

Reply to
cmk128

--What he said; and if you want to vary speed you just change the numbers. It's possible to program rise and fall, to make motion more "natural" too. I recall there's an exercise in the Parallax BOE-bot book that describes various programming shortcuts to do this.

Reply to
steamer

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