To much torque

Hi,

http://www.societyofrobots.com/robot...lculator.shtml

I was trying to calculate the torque for my robotic arm from this website calculator

Here is the spec

motor Hitec ,Torque 10 kg/cm

L1 (Length from shoulder to elbow) 7 inches weight W1 steel frame about 5 g
L2 (Length from elbow to wrist) 5 inches weight W2 steel frame about 4 g
L3 (Length from elbow to gripper) 3 inches weight W3 steel frame about 2 g

W4 object to lift 1kg

M1 (Shoulder 1 motor ) 25g
M2 (Elbow 2 motors) 50g
M3 (gripper 2 motors) 50g

I want to lift 1kg object

I left the Joint Rotational Acceleration blank 0

It is showing about 40kg/cm torque ,Is it correct?

If it is true ,is there any way around it?.

I could not find any servo motor with that torque.Even if I do find ,it will be pretty expensive

Sounds exactly right to me. (15 inches is 38.1 CM) so 1 KG at 38.1 cm is 38.1 kgcm. I’m no expert on servos but for something that was originally made for radio controlled models high torque probably isn’t their forte. If you want to lift a Kg I’d say a geared stepper motor is the way to go. It won’t be cheap…

Well there are some pretty large R/C servos avalible, used for large landing gears and such. Here is one I found doing a quick search:

https://www.unitedhobbies.com/UNITEDHOBBIES/store/uh_viewItem.asp?idProduct=8496&Product_Name=Turnigy_S8166M_Servo__154g_/33kg/_.21sec

Lefty