Epson SCARA GX Series, Manual

Page: 159 / 236

GX8 Manipulator 4. Setting of End Effectors
GX series Rev.2 149
4.3 Weight and Inertia Settings
To ensure optimum Manipulator performance, it is important to make sure that the load (weight
of the end effector and work piece) and moment of inertia of the load are within the maximum
rating for the Manipulator, and that Joint #4 does not become eccentric.
If the load or moment of inertia exceeds the rating or if the load becomes eccentric, follow the
steps below, “
4.3.1 Weight Setting ” and “ 4.3.2 Inertia Setting ” to set parameters.
Setting parameters makes the PTP motion of the Manipulator optimal, reduces vibration to
shorten the operating time. In addition, it reduces persistent vibration produced when the
moment of inertia of the end effector and work piece is larger than the default setting.
4.3.1 Weight Setting
CAUTION
■
The total weight of the end effector and the work piece must not exceed 8 kg. The
GX8 series Manipulators are not designed to work with loads exceeding 8 kg.
Always set the Weight parameters according to the load. Setting a value that is
smaller than the actual load may cause errors, excessive shock, insufficient
function of the Manipulator, and/or shorten the life cycle of parts/mechanisms.
The acceptable weight capacity (end effector and work piece) in GX8 series is 4 kg at the
default rating and 8 kg at the maximum.
When the load (weight of the end effector and work piece) exceeds the rating, change the
setting of Weight parameter.
After the setting is changed, the maximum acceleration/deceleration speed of the robot
system at PTP motion corresponding to the “Weight Parameter” is set automatically.
Load on the Shaft
The load (weight of the end effector and work piece) on the shaft can be set by Weight
parameter.
EPSON
RC+
Enter a value into the [Load inertia:] text box on the [Inertia] panel ([Tools] - [Robot
Manager]). (You may also execute the Inertia command from the [Command Window].)
Load on the Arm
When you attach a camera or other devices to the arm, calculate the weight as the equivalent
of the shaft. Then, add this to the load and enter the total weight to the Weight parameter.
Also, when the external wiring option (excluding cables) is mounted near the user connector
on the Arm #2 side, add 0.16 kg to the equivalent weight conversion value of the shaft.
Equivalent Weight Formula
When you attach the equipment near Arm #2:
When you attach the equipment to the end of Arm #2:
W
M
= M (L
1
) 2 /(L
1
+L
2
) 2
W
M
= M (L
M
) 2 /(L
2
) 2
W
M
M
L
1
L
2
L
M
: equivalent weight
: weight of camera etc.
: length of Arm #1
: length of Arm #2
: distance from rotation center of Joint #2 to center of gravity
of camera etc.