WEIGHT Setting
CAUTION
Set the total weight of the hand and the workpiece smaller than the maximum payload.
The C4 Manipulators can operate without limitations on the condition unless and until the load exceeds this maximum payload. When the payload of the Manipulator exceeds the maximum payload, refer to the section “Restrictions on payload exceeding the maximum payload” in the later part of this section for details.
Always set the Weight parameters of the WEIGHT command according to the load. Setting a value smaller than the actual weight may cause errors or impact that not only impair full functionality but also shorten the life of the mechanical components.
The acceptable weight capacity (hand + workpiece) for C4 Manipulators is as follows:
| Rated | Maximum |
|---|---|
| 1 kg | 4 (5) kg* |
When the load exceeds the rating, change the setting of the weight parameter. After changing the Weight parameter setting, the maximum acceleration/deceleration and speed of the robot system corresponding to the load is set automatically.
* If the payload exceeds the maximum payload, refer to the following section.
"WEIGHT Setting - Restrictions on payload exceeding the maximum payload"
Setting method of Weight parameters
Select [Tools]-[Robot Manager]-[Weight] panel and set the value in [Weight:]. You may also execute the Weight command from [Command Window].
Load on the Manipulator
Mounting location of the load
C4-B601**
| Symbol | Description |
|---|---|
| a | Load on the fore end of Arm #6 |
| b | Arm #5 deck |
| c | Arm #3 deck |
C4-B901**
| Symbol | Description |
|---|---|
| a | Load on the fore end of Arm #6 |
| b | Arm #5 deck |
| c | Arm #3 deck |
C4 series
Deck detailed
(Units: mm)
| Arm #5 deck | Arm #3 deck |
|---|---|
 |  |
When you attach the equipment to the decks on the upper arm, convert its weight into equivalent weight assuming that the equipment is attached to the end of the Arm #6. Then, this equivalent weight added to the load will be a Weight parameter.
Calculate the Weight parameter by using the formula below and enter the value.
Weight Parameter Formula
Weight parameter = Mw+ Wa + Wb
- Mw: Payload on the fore end of Arm #6 (kg)
- Wa: Equivalent weight of the Arm #3 deck (kg)
- Wb: Equivalent weight of the Arm #5 deck (kg)
- Wa=Ma (La)2/ (L)2
- Wb=Mb (Lb)2/ (L)2
- Ma: Weight of the air valve on the Arm #3 deck (kg)
- Mb: Weight of the camera on the Arm #5 deck (kg)
- L: Length of the upper arm (315 mm)
- La: Distance between the Joint #3 and the center of gravity of the air valve on the Arm #3 deck (mm)
- Lb: Distance between the Joint #3 and the center of gravity of the camera on the Arm #5 deck (mm)
[Example]
When the following loads apply to C4 which fore end of the Arm #6 is 315 mm (L) away from the Joint #3 and payload (Mw) is 1 kg:
- Load on the Arm #3 deck is 1.5 kg (Ma). The deck is 0 mm (La) away from the Joint #3.
- Load on the Arm #5 deck is 0.5 kg (Mb). The deck is 280 mm (Lb) away from the Joint #3.
Wa=1.5 × 02/3152=0
Wb=0.5 × 2802/3152=0.395 → 0.4 (round up)
Mw+Wa+Wb=1+0+0.4=1.4
Enter "1.4" for the Weight parameter.
Automatic Speed Setting by Weight Parameter (C4-B601**)
Automatic Speed Setting by Weight Parameter (C4-B901**)
- The percentage in the graph is based on the speed at rated weight (1 kg) as 100%.
- If the payload exceeds the maximum payload, refer to the following section.
"WEIGHT Setting - Restrictions on payload exceeding the maximum payload"
Restrictions on payload exceeding the maximum payload
Maximum payload for C4 Manipulators is as follows:
Payload can be increased by restricting the arm posture of the Arm #5 downward.
| Max. Payload | Max. Payload with Pose Restriction |
|---|---|
| 4 kg | 5 kg |
If the load exceeds the maximum payload, use the Arm #5 with a posture angle within the range indicated in the following graph.
The graph shows the relation of the load weight and Arm #5 angle limit (A1) measured in vertical direction (direction of gravity). Note that the heavier the load on the Arm #6, the smaller the angle limit becomes.
When the Manipulator operates vertically to the operating surface, the limit of the Arm #5 is equivalent to the limit of the operating angle (A2).
In addition, for the eccentric load, the angle limit is an angle of the line joining the center of the load and the Arm #5 rotation axis with the vertical direction (B).
The eccentricity of the load should be within the allowable moment and moment of inertia of Arms #4, #5, and #6.
Relation of load weight and Arm #5 angle limit
Relation of Arm #5 angle and operating surface
| Symbol | Description |
|---|---|
| a | Arm #4 |
| b | Arm #5 rotation axis |
| c | Arm #5 |
| d | Arm #6 |
| e | Load on the fore end of Arm #6 |
| f | Vertical direction |
| g | Plane |
| h | Operating surface |
Angle limit for eccentric load
| Symbol | Description |
|---|---|
| a | Arm #5 rotation axis |
| b | Arm #5 |
| c | Arm #6 |
| d | Center of gravity |
| e | Load on the fore end of Arm #6 |
| f | Vertical direction |