IAI America RCP2W-GRLS - Manual (Page 122)

112
1
1. Appendix
Confirm that the value calculated above is equal to or less than the applicable allowable load moment in
Table 2.
Step 3: Check the external forces applied to the finger
When the gripper is installed on a Cartesian robot, articulated robot or any other actuator and caused
to perform a linear or rotary motion, its work part and finger attachments receive external forces other
than the gripping force.
(1) Allowable load torque
Make sure the load torque applied to the finger is equal to or less than the maximum allowable load
torque.
m
1
: Mass of the work part (kg)
m
2
: Mass of the finger attachment (kg)
R
1
: Distance from the center of gravity of the work part to the finger opening/closing fulcrum (mm)
R
2
: Distance from the center of gravity of the finger attachment to the finger opening/closing fulcrum
(mm)
F
1
: External force applied to the work part (N)
F
2
: External force applied to the finger attachment (N)
T
0
: Torque generating on the finger due to an external force (N.m)
‹ External forces applied to the work part and finger attachment
Based on the use conditions of the gripper, calculate the following external forces applied to the
work part and finger attachment and add up the calculated forces:
a) Weight of the work part and finger attachment
F = mg g: Gravitational acceleration
b) Inertial force when the gripper performs a linear motion
F = ma a: Acceleration/deceleration during movement
c) Centrifugal force when the gripper performs a rotary motion
F = mr
Z 2
r: Radius of rotation,
Z: Angular velocity
Total external forces
--- External force applied to the work part
--- External force applied to the finger attachment
Model
Allowable inertial
moment
I
max
[kg m 2 ]
Mass (reference
value)
max [kg]
RCP2-GRLS 1.5 x 10 -4 0.05
RCP2-GR3LS 3.0 x 10
-4
0.1
RCP2-GR3LM 9.0 x 10
-4
0.2
(3) Total inertial moment around the Z-axis (fulcrum)
R
1
: Distance from the center of gravity of A to the
finger opening/closing fulcrum [mm]
R
2
: Distance from the center of gravity of B to the
finger opening/closing fulcrum [mm]
Table 2 Allowable Inertial Moments of Fingers *Note 1
Gripping point
Center of gravity
of the work part
Gripping point
Center of gravity
of the work part
Center of gravity of the finger
attachment
Center of gravity of the finger
attachment Fulcrum
Fulcrum