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how do I determine power requirements for an 18 towerpro mg955 servo hexapod?

I recently bought a Chinese made hexapod and 32 servo Torobot controller.  Hooking up the bluetooth module to the controller was easy, and so was connecting all 18 hexapod servos, and the programming looks straightforward.

the servos are towerpro mg955.  I have found various info on these (including comments re their quality) but was not able to find out anything about how much current they can use/need under load

I am not worried about the power supply for the servo controller (which works fine), but the 6v 2a supply (wall wart) I am using for the servos seems to be inadequate (servos become spastic/disfunctional when I try to connect and move more than 6 or 7 servos).  that tells me I need more power for the servos.

does anyone know how much current one of these servos uses under load?

also, what battery would I use once I want the hexapod to run without connecting to a wall power supply?

any help appreciated (and sorry if this should be in the newbie forum)

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according to this

http://www.rcgroups.com/forums/showthread.php?t=650962

these servos consume in 4,v 350mA ,so the best thing is use in 5v what give us 365mA

0,365mA*7(quantity you choose)=2,5A

Yes I'm quite sure it's the same.

ok thank you very much for all your help :)

All I know is that the Torobot controller will work with MG995/MG996R servos. I have both and have tried them with the Torobot controller. http://www.bajdi.com/torobot-32-channel-servo-controller/

ok thank you very much for your help :) do you know if the link i had ( http://www.elechouse.com/elechouse/index.php?main_page=product_info&cPath=100_146&products_id=1883 ) is the same board you know that works?

MG995 servo's are plain simple analog servo's. http://www.servodatabase.com/servo/towerpro/mg995

so will they even work with the supplied servo controller board if they are analogue? The servo controller seems to suggest only digital servo support...

http://www.elechouse.com/elechouse/index.php?main_page=product_info&cPath=100_146&products_id=1883        i think thats the board supplied with the robot...

 

http://www.glyby.com/arduino-alumin-hexapod-spider-six-3dof-legs-robot-with-18-servos-32-channel-servo-controller-board_p12445.html      <-- thats the link to the robot

so wil they even work with the supplied servo controller board if they are analogue? The servo controller seems to suggest only digital servo support...

http://www.elechouse.com/elechouse/index.php?main_page=product_info&cPath=100_146&products_id=1883        i think thats the board supplied with the robot...

 

http://www.glyby.com/arduino-alumin-hexapod-spider-six-3dof-legs-robot-with-18-servos-32-channel-servo-controller-board_p12445.html      <-- thats the link to the robot

I am planning on purchasing one of these bots, but are the servo's included digital or analogue? some websites say they're digital, some say theyre analogue :/

The power draw for your servos will vary greatly depending on the motion of the robot and battery voltage. As a rule of thumb, allow at least 1A per servo. If you want more accurate information then you are better off powering a servo directly from the battery you will use with an amp meter in series. Test your servo under heavy load and stall it if possible. Basically your 18 servo robot can draw 20A or more when performing a strenuous motion such as climbing, running quickly or carrying a heavy load.