Other Settings
Weight Settings
Set the weight of the hand. Set the correct total weight of the attached hand (including the tool adapter and other peripherals) and the workpiece. There are two methods for configuring settings.
Configuration method 1: Setting the weight in the settings screen
For more information, refer to the following manual.
"Epson RC+ 8.0 User's Guide - [Robot Manager] Command (Tools Menu) - [Tools]-[Robot Manager]-[Weight] Page"
The [Length] does not normally need to be changed.
Configuration method 2: Setting the weight using SPEL+ commands
For more information, refer to the following manual.
"SPEL+ Language Reference - Weight Statement, Weight Function"
Example settings
This section describes the procedure used to set the Weight value using configuration methods 1 and 2 under the following conditions.
| Component | Weight [kg] |
|---|---|
| Hand unit | 1.0 |
| Tool adapter | 0.2 |
| Workpiece | 0.5 |
| Wiring, piping, etc. | (This can be ignored) |
| Total | 1.7 |
Configuration method 1: In the [Weight] panel, enter “1.7” in the [Weight] field, and then select the [kg] button.
Configuration method 2: Enter and execute the following command in the command window.
> Weight 1.7
CAUTION
- The combined weight of the hand and the workpiece must be equal to or less than the maximum transportable weight. For more information about the maximum transportable weight, refer to the manipulator manual. Make sure to set the Weight setting according to the load. Setting the weight setting to a lower value than the actual weight may cause errors or excess vibration, and prevent the robot from functioning properly, and reduce the lifespan of each component.
- Once set, weight settings are kept even when the power is turned off.
KEY POINTS
You can also execute the Weight command by running it in a SPEL+ program. However, as the Weight setting is stored to the internal controller storage media (compact flash / SD card), frequently executing this command within the program (particularly when on a loop) will adversely affect the life of the storage media. It is recommended that limit using this command as much as possible.
Inertia Settings and Eccentricity Settings
Moment (of inertia) and inertia settings
The moment of inertia is an amount that indicates the difficulty in getting a physical object to turn. This is expressed as values such as the moment of inertia, inertia, or GD2. When moving a hand attached to a shaft or flange, ensure that the total moment of inertia of the hand (including the tool adapter and other peripherals) and the workpiece does not exceed the maximum allowable value for the manipulator. There are two methods for configuring settings. Set this in conjunction with the eccentricity described in the next section.
Configuration method 1: Configuring settings in the settings screen
For more information, refer to the following manual.
"Epson RC+ 8.0 User's Guide - [Robot Manager] Command (Tools Menu) - [Tools]-[Robot Manager]-[Eccentricity] Page"
Configuration method 2: Configuring settings using SPEL+ commands.
> Inertia 0. 01
For more information, refer to the following manual.
"SPEL+ Language Reference - Inertia Statement, Inertia Function"
CAUTION
Always set the eccentric quantity parameter according to the eccentric quantity. Setting a value that is smaller than the actual eccentric quantity may cause errors, excessive shock, insufficient function of the Manipulator, and/or shorten the life cycle of parts/mechanisms.
KEY POINTS
You can also execute the Inertia command by running it in a SPEL+ program. However, as the Inertia setting is stored to the internal controller storage media (compact flash / SD card), frequently executing this command within the program (particularly when on a loop) will adversely affect the life of the storage media. It is recommended that limit using this command as much as possible.
How to calculate the moment of inertia
The following example shows how to calculate the moment of inertia for the load (the total of the hand and workpiece, including the tool adapter and other peripherals).
The moment of inertia for the total load is found by calculating the sum of components (A) to (C).
| Symbol | Item |
|---|---|
| a | Rotation center |
| b | Shaft |
| A | Hand |
| B | Workpiece |
| C | Workpiece |
The methods for calculating the moment of inertia for (A), (B), and (C) are shown below. Calculate the total moment of inertia using the basic formulas.
(A) Moment of inertia of a rectangular parallelepiped
| Symbol | Item |
|---|---|
| a | Rotation center |
| b | Rectangular parallelepiped’s center of gravity |
| m | Weight |
(B) Moment of inertia of a cylinder
| Symbol | Item |
|---|---|
| a | Cylinder’s center of gravity |
| b | Rotation center |
| m | Weight |
(C) Moment of inertia of a sphere
| Symbol | Item |
|---|---|
| a | Rotation center |
| b | Sphere’s center of gravity |
| m | Weight |
How to calculate eccentricity
Set the following value as the eccentricity of the load (the total of the hand and workpiece, including the tool adapter and other peripherals.)
| Symbol | Item |
|---|---|
| a | Rotation center |
| b | Attachment face |
| c | Position of center of gravity of load |
| d |
|
| e |
Tool Settings
Set Tool coordinate systems for the attached hand as follows to move the robot as intended when jogging. This is particularly useful in reducing the risk of collision when controlling the hand in the vicinity of the workpiece and other obstacles.
Of the Tool coordinate systems, the Tool 0 coordinate system is preset to the tip of the shaft (for a SCARA robot), or the center of the flange face (for a 6-axis robot), and cannot be changed. 15 Tool coordinate systems (Tool 1 to Tool 15) can be set by the user.
Example 1: For a SCARA robot, set the vacuum pad surface part of a suction hand to the Tool 1 coordinate system
If the center of the vacuum pad of a mounted hand is offset from the center of axis at the base of the shaft as described below:
x axis direction: 20mm
z axis direction: -100mm
Set the Tool 1 coordinate system as follows.
Tool 1: Offset amount from Tool 0
| x | y | z | u | v | w |
|---|---|---|---|---|---|
| 20 | 0 | -100 | 0 | 0 | 0 |
Epson RC+ 8.0 User's Guide - [Robot Manager] Command (Tools Menu) - [Tools]-[Robot Manager] - [Tools] Page
To perform a jog motion in the specified tool coordinate system:
- Open the [Jog & Teach] screen.
- Set the [Mode] to Tool.
- In the [Tool:] field, select the tool coordinate system set above (in this example, 1).
- Click jog buttons.
This will move the robot based on the coordinate axis specified by the Tool 1 coordinate system.
Example 2: Setting the finger tip (gripping point) of the chuck hand on a 6-axis robot to the Tool 2 coordinate system
Offset the gripping point of the attached hand from the center of the flange surface as follows:
- Y-axis direction: 50mm
- Z-axis direction: 120mm
If, in addition to this, the hand is attached with a 90 degree rotation around the Z-axis:
Set the Tool 2 coordinate system as follows.
Tool 2: Offset amount from Tool 0
| x | y | z | u | v | w |
|---|---|---|---|---|---|
| 0 | 50 | 120 | -90 | 0 | 0 |
Select the tool coordinate system set in the [Jog & Teach] screen in the same way as example 1 to move the hand based on this coordinate axis.
KEY POINTS
While an offset has been added in the X-axis and Y-axis direction to provide an example, it is recommended that the center of gravity for the whole hand matches the center of the shaft axis (on a SCARA robot) or the center of the flange surface (J6 axis) as closely as possible. If an offset occurs, refer to the following to set the correct degree of eccentricity.
"Inertia Settings and Eccentricity Settings"
The Tool 0 coordinate system is set to the tip of the shaft (for a SCARA robot), or the center of the flange face (for a 6-axis robot). This cannot be changed.
You can use CAD data on the hand and tool adapter to display the hand and the tool coordinate system on the simulator screen using the Epson RC+ simulator function.
For more information, refer to the following manual.
"Epson RC+ 8.0 User's Guide - Simulator"
