how much torque to push an object

[assaf_lev]

Hi guys,
I am building a motion racing simulator.
i am trying to calc what are the characteristics of the motor that i need.

i want to raise 80 kg (160 lbs) with a servo motor
the motor is connected to a 8" (20cm) arm. the arm is connected to the weight, and needs to raise it 180 degrees from buttom to top.

i need it to achieve 2 g's and 75 rpm.

i thought using a planetary reducer, ratio 1:40 ,and a servo motor that turns at 3000 rpm
i calculated that a motor rated at 200w and 0.6nm (times 40 after reduction will give me more then enough torque) will suffice.
is that correct ?
can you show me the math ?
Thanks a lot !

i.e

[jessicaherron9]

To calculate load torque, multiply the force (F) by the distance away from the rotational axis, which is the radius of the pulley (r). If the mass of the load (blue box) is 20 Newtons, and the radius of the pulley is 5 cm away, then the required torque for the application is 20 N x 0.05 m = 1 Nm