IAI America RS - Manual (Page 35)

4. Operational Conditions
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4. Operational Conditions
4.1 Load Inertia
Operate with the load inertia within the allowable range.
Load inertia
Type
Deceleration
ratio
kg•m 2 (kgf•cm•s 2 )
1/50 0.058 (0.59)
RS-30
1/100 0.23 (2.35)
1/50 0.11 (1.1)
RS-60
1/100 0.42 (4.3)
٧
Regarding the load inertia
The rotary actuator is an actuator that applies a rotational torque to the loaded work piece and
makes the work piece have a rotational motion.
The rotational torque applies the load inertia and angular acceleration that can be figured out with
the following formula.
T = J•Į
T : Torque N•m (kgf•cm)
J : Load inertia kg•m 2 (kgf•cm•s 2 )
Į : Angular acceleration rad/s 2
i.e. applying a torque to an object with load inertia generates an angular acceleration. Therefore, for
the rotary actuator, the loadable amount is expressed with the load inertia.
٧ Calculation of the Load Inertia
Load inertia is a specific value for an object determined by the weight and profile.
It is to be calculated as;
J = ³ r 2 dM
r : Distance from center
dM : Small mass
For example, if the loaded work piece is offset from the rotary shaft, the following formula can be
applied.
J = M•r 2
M : Mass of the loaded piece (kg)
r : Distance from the center (Offset distance) (m)
(Offset distance)
r
M
(Loaded
work piece)
typically Z is used for
angular velocity