trouble with controlling servos

hi, im using seeeduino mega and im having trouble controlling 12 servos connected to the pins of the seeeduino mega. im using the megaservo library too.

the servos are jittery but from googling i guess that is a common problem due to the inaccuracy of the servo pots? im using HXT micro hobby servos

my real trouble is that the seeeduino keeps resetting itself while the servos are moving.. i connected a 7.4V 2000mAh lipo battery to the Vin pin and the servos are all connected to 5V pin.

is the cause of the resets due to insufficient power supply? please advise.. thanks!

my real trouble is that the seeeduino keeps resetting itself while the servos are moving.. i connected a 7.4V 2000mAh lipo battery to the Vin pin and the servos are all connected to 5V pin.

Your problem is that you can't power multiple servos from the board's +5vdc pin. This voltage comes from the on-board +5vdc voltage regulator and can't supply more then about maybe 500-800ma maximum before it will shutdown in protection mode. That is what is causing your reset problem.

You really need an external DC power supply or external battery of not more then +6vdc (servo max voltage) and I usually recommend a current rating for the external voltage source of one amp per servo. The actual current demand for 12 servos depend on the specific servos used, how much mechanical load is on them and how many are moving at the same time.

Also when you get the proper external DC voltage source, be sure the external voltage source's ground is wired to the Arduino ground.

Lefty

Here is a thread where I show running 18 servos.
http://www.arduino.cc/cgi-bin/yabb2/YaBB.pl?num=1265626147/6#6

Separate power supply for the servos.
Ground connected to Arduino.
Signal pins from Arduino to servos.

And the thread with a movie of the hexapod.

edit: I guess I left off the link to the thread with the movie: http://www.arduino.cc/cgi-bin/yabb2/YaBB.pl?num=1267069898/0