rotary actuator size

[simone17]

hello to all are in difficulty with the sizing of a rotating actuator.
the data are as follows:
I have to rotate a mass object 3kg with inertia time of 800kgcm2 in 0.5 sec I can not understand what couple needs the actuator(ncm)

Hi.

 

[cacciatorino]

hello to all are in difficulty with the sizing of a rotating actuator.
the data are as follows:
I have to rotate a mass object 3kg with inertia time of 800kgcm2 in 0.5 sec I can not understand what couple needs the actuator(ncm)

Hi.

then, considering a triangular ramp (0.25 seconds to speed up and 0.25 to brake at the end of the race), pretending that the rotation is 180° (you did not specify), you get an average angle speed of:

3.14 rad/0.5 sec = 6.28 rad/sec.

from which a maximum speed of 12.56 rad/sec. so you have to get from vel=0 to vel.=12.56 in 0.25 seconds. achieve an acceleration of:

a=(12.56 rad/sec) / 0.25 sec= 50 rad/sec^2 (more or less)

then, the pair gets as c = i * a, being:

i = 800 kg * cm^2 = 800 kg * 0.0001 m^2 = 0.08 kg*m^2

from which:

c = i * a = 0.08 * 50 = 4 nm.

the power should be

p = c * omega_max= 4 nm * 12.56 rad/sec = 50 watts.

Now it should be enough to multiply everything for a safety coeff 15:biggrin: to take into account frictions and uncertainties and approximations of the calculation.

 

[sampom]

safety coeff. 15

The people!

Takes.

Salujah
by Marco:smile

 

[bisogna_rimanere_umili]

then, considering a triangular ramp
Now it should be enough to multiply everything for a safety coeff 15:biggrin: to take into account frictions and uncertainties and approximations of the calculation.

and maybe sleep quieter at night...

 

[simone17]

thanks to the explanation works!! !
the angle of rotation is 90°
I still have a question but if the actuator is put with the rotation axis parallel to the ground or perpendicular the necessary torque to the rotation changes (think of yes) but how do you calculate?? ? ?
Thank you.