Epson C8 Series Manipulator Manual page 63

The moment M (Nm) and inertia moment I (kgm
+ work piece) is small can be obtained by the following formula.
M (Nm) = m(kg) × L (m) × g (m/s
I (kgm
m : Weight of load (kg)
L : Eccentric quantity of load (m)
g : Gravitational acceleration (m/s
The figure below shows distribution of the center of gravity when the volume of the load
(end effector + work piece) is small.
Design the end effector so that the center of gravity is within the allowable moment.
If the volume of the load is large, calculate the moment and inertia moment by referring to
Setup & Operation 4.3.2 INERTIA setting - Calculating the Inertia Moment.
Max. Eccentric Quantity of Load
(Distance between the joint rotation center and the load's center of gravity)
Joint
#4
#5
#6
When calculating the critical dimension of the load using the allowable moment and inertia
moment, the calculated value represents a distance from the Arm #5 rotation center, not the
distance from the flange. To calculate the distance from the flange to the load's center of
gravity, subtract the distance from the center of the Arm #5 rotation center to the flange (=80
mm) as shown in the example below.
C8 Rev.13
2 ) = m(kg) × L 2 (m)
300
250
200
150
100
50
0
0 50
Center of gravity of load from the Arm #5 rotation center [mm]
1 kg 2 kg
300 mm 300 mm 300 mm
300 mm 300 mm 300 mm
300 mm 274 mm 224 mm
Setup & Operation 4. End Effectors
2 ) when the volume of the load (end effector
)
2
)
2
100 150
3 kg 4 kg 5 kg
300 mm 300 mm
300 mm 300 mm
194 mm 173 mm
L
Joint Rotation Center
T
200 250 300
6 kg 7 kg
280 mm 242 mm
280 mm 242 mm
158 mm 137 mm
1 kg
2 kg
3 kg
4 kg
5 kg
6 kg
7 kg
8 kg
8 kg
212 mm
212 mm
120 mm
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