Setting the Work Envelope by Mechanical Stops
Mechanical stops set the absolute work envelope that physically limits where the Manipulator can move.
Both Joints #1 and #2 have threaded holes in positions corresponding to angles for the setting area. The positions of the mechanical stops (variable) set the work envelope. Install the bolts in the threaded holes corresponding to the angles to be set.
Joint #3 can be set to any length less than the maximum stroke.
Table top mounting specifications
| Symbol | Description |
|---|---|
| a | Joint #3 mechanical stop (lower limit mechanical stop) |
| b | Joint #3 mechanical stop (upper limit mechanical stop) *Do not move the position. |
| c | Joint #2 mechanical stop (variable) |
| d | Joint #1 mechanical stop (fixed) |
| e | Joint #1 mechanical stop (variable) |
| f | Joint #2 mechanical stop (fixed) |
Wall mounting specifications
Only the stop positions that are different from the model with table top mounting specifications are explained here.
| Symbol | Description |
|---|---|
| a | Joint #1 mechanical stop (fixed) |
| b | Joint #1 mechanical stop (variable) |
Ceiling mounting specifications
Only the stop positions that are different from the model with table top mounting specifications are explained here.
| Symbol | Description |
|---|---|
| a | Joint #1 mechanical stop (fixed) |
| b | Joint #1 mechanical stop (variable) |
Setting the Mechanical Stops of Joints #1 and #2
Both Joints #1 and #2 have threaded holes in positions corresponding to angles for the setting area. The positions of the mechanical stops (variable) set the work envelope.
Use the following procedure to install the bolts in the holes corresponding to the angle that you want to set.
- Turn off the Controller.
- Install a hexagon socket head cap bolt into the threaded hole corresponding to the setting angle, and tighten it.
| Joint # | Hexagon Socket Head Cap Bolt | Number of Bolts | Recommended Tightening Torque | Strength |
|---|---|---|---|---|
| 1 | M10 × 20 full thread | 1 for each side | 18.0 N·m (194 kgf·cm) | ISO 898-1 property class 10.9 or 12.9 equivalent |
| 2 | M8 × 10 full thread |
Turn on the Controller.
Set the pulse range corresponding to the new positions of the mechanical stops.
KEY POINTS
Be sure to set the pulse range inside the positions of the mechanical stop range.
Example: Setting Joint #1 to -135° to +135° and Joint #2 to -125° to +125° for the GX8-A**2S*
Execute the following command in [Command Window].>JRANGE 1,-819200,4096000 'Sets the pulse range of Joint #1 >JRANGE 2,-2275556,+2275556 'Sets the pulse range of Joint #2 >RANGE 'Confirms the setting value using the Range statement -819200,4096000,-2275556,2275556,-1092267,0,-1668189, 1668189Move the arm by hand until it touches the mechanical stops to check that nothing will hinder the arm motion during operation, such as by hitting peripheral equipment.
Operate the joint with the new settings at low speeds until it reaches the positions of the minimum and maximum values of the pulse range. Check that the arm does not hit any mechanical stops.
(Check the position of the mechanical stops and the motion range that were set.)Example: Setting Joint #1 to -85° to +115° and Joint #2 to -100° to +100° for the GX8-A**2S*
Execute the following command in [Command Window].>MOTOR ON 'Turns on the motor >POWER LOW 'Sets to low power mode >SPEED 5 'Sets to low speed >PULSE 91022,0,0,0 'Moves to the minimum pulse position of Joint #1 >PULSE 3731912,0,0,0 'Moves to the maximum pulse position of Joint #1 >PULSE 1638400,-1820444,0,0 'Moves to the minimum pulse position of Joint #2 >PULSE 1638400,1820444,0,0 'Moves to the maximum pulse position of Joint #2
The Pulse statement (Go Pulse statement) moves all joints to the specified positions at the same time. Set safe positions after taking into consideration the motion of the joints whose pulse range have been changed and also the other joints.
In this example, when checking Joint #2, Joint #1 is moved to the 0° position (pulse value: 1638400) near the center of its work envelope.
If the arm hits a mechanical stop or if an error occurs after the arm hits a mechanical stop, either reset the pulse range to a narrower pulse range so that nothing blocks the arm motion, or extend the positions of the mechanical stops within the limit.
Joint #1 mechanical stop
| Mounting Specifications | Arm Length (mm) | a | b | c | d | e | f | |
|---|---|---|---|---|---|---|---|---|
Max. motion range (deg.) | Table top | 450, 550, 650 | 152° | 135° | 115° | -115° | -135° | -152° |
| Ceiling | 450 | - | 105° | 85° | -85° | -105° | - | |
| 550, 650 | 152° | 135° | 115° | -115° | -135° | -152° | ||
| Wall | 450 | - | 105° | 85° | -85° | -105° | - | |
| 650 | 148° | 135° | 115° | -115° | -135° | -148° | ||
Max. pulse range (pulse) | Table top | 450, 550, 650 | 4405476 | 4096000 | 3731912 | -455111 | -819200 | -1128676 |
| Ceiling | 450 | - | 3549867 | 3185778 | 91022 | -273067 | - | |
| 550, 650 | 4405476 | 4096000 | 3731912 | -455111 | -819200 | -1128676 | ||
| Wall | 450 | - | 3549867 | 3185778 | 91022 | -273067 | - | |
| 650 | 4332658 | 4096000 | 3731912 | -455111 | -819200 | -1055858 |
GX8-*55**W only
| Mounting Specifications | Arm Length (mm) | g | h | i | j | k | l | |
|---|---|---|---|---|---|---|---|---|
Max. motion range (deg.) | Wall | 550 | 135 | 85 | 55 | -55 | -85 | -135 |
Max. pulse range (pulse) | 4096000 | 3185778 | 2639645 | 637156 | 91022 | -819200 |
Joint #2 mechanical stop
Max. motion range (deg.):
| Arm Length (mm) | Mounting Specifications | Environmental Specifications | Z-value Range (mm) | m | n | o | p | q |
|---|---|---|---|---|---|---|---|---|
| 450 | Table top | S, E | 0 ≥ Z ≥–270 | +100 | +125 | ±147.5 | -125 | -100 |
| –270 > Z ≥ –330 | ±145 | |||||||
| C, P | 0 ≥ Z ≥ –240 | ±147.5 | ||||||
| –240 > Z ≥ –300 | ±137.5 | |||||||
| Ceiling | S, E, C, P | - | +79 | +103 | ±125 | -103 | -79 | |
| Wall | ||||||||
| 550 | Table top | S, E | - | +100 | +125 | ±147.5 | -125 | -100 |
| C, P | 0 ≥ Z ≥ –240 | ±147.5 | ||||||
| –240 > Z ≥ –300 | ±145 | |||||||
| Ceiling | S, E | - | ±147.5 | |||||
| C, P | - | ±145 | ||||||
| Wall | S, E | - | ±147.5 | |||||
| C, P | - | ±145 | ||||||
| 650 | Table top | S, E, C, P | - | ±147.5 | ||||
| Ceiling | ||||||||
| Wall |
Max. pulse range (pulse):
| Arm Length (mm) | Mounting Specifications | Environmental Specifications | Z-value Range (mm) | m | n | o | p | q |
|---|---|---|---|---|---|---|---|---|
| 450 | Table top | S, E | 0 ≥ Z ≥–270 | +1820444 | +2275556 | ±2685156 | -2275556 | -1820444 |
| –270 > Z ≥ –330 | ±2639644 | |||||||
| C, P | 0 ≥ Z ≥ –240 | ±2685156 | ||||||
| –240 > Z ≥ –300 | ±2503111 | |||||||
| Ceiling | S, E, C, P | - | +1438151 | +1875058 | ±2275556 | -1875058 | -1438151 | |
| Wall | ||||||||
| 550 | Table top | S, E | - | +1820444 | +2275556 | ±2685156 | -2275556 | -1820444 |
| C, P | 0 ≥ Z ≥ –240 | ±2685156 | ||||||
| –240 > Z ≥ –300 | ±2639644 | |||||||
| Ceiling | S, E | - | ±2685156 | |||||
| C, P | - | ±2639644 | ||||||
| Wall | S, E | - | ±2685156 | |||||
| C, P | - | ±2639644 | ||||||
| 650 | Table top | S, E, C, P | - | ±2685156 | ||||
| Ceiling | ||||||||
| Wall |
Setting the Mechanical Stop of Joint #3
KEY POINTS
This method can be used only for the Manipulator models with standard specifications (GX8-****S*) and ESD specifications (GX8-****E*).
For Manipulator models with cleanroom & ESD specifications (GX8-****C*) and protected-model (GX8-****P*), the work envelope set by the Joint #3 mechanical stop cannot be changed.
Turn on the Controller, and turn off the motors using the Motor OFF statement.
Push up the shaft while pressing the brake release switch.
Do not push the shaft up to its upper limit or it will be difficult for the arm top cover to be removed. Push the shaft up to a position where the Joint #3 mechanical stop can be changed.
Symbol Description a Brake release switch b Lower limit mechanical stop c Shaft KEY POINTS
When you press the brake release switch, the shaft may lower or rotate due to the weight of the hand. Be sure to hold the shaft by hand while pressing the switch.
Turn off the Controller.
Loosen the low-profile hexagon socket head cap bolts (2 × M5) on the lower limit mechanical stop.
KEY POINTS
A mechanical stop is mounted on both the top and bottom of Joint #3. However, only the position of the lower limit mechanical stop on the top can be changed. Do not remove the upper limit mechanical stop on the bottom because the origin position of Joint #3 is determined by this stop.
The upper end of the shaft defines the maximum stroke position. Move the lower limit mechanical stop down by the length that you want to limit the stroke.
For example, when the lower limit mechanical stop is set at the "200 mm" stroke, the lower limit Z coordinate value is "-200". To change this value to "-150", move the lower limit mechanical stop down by "50 mm". Use calipers or similar tool to measure the distance when adjusting the mechanical stop.
Symbol Description a Measurement length Adjust the low-profile hexagon socket head cap bolts (2 × M5) of the lower limit mechanical stop so that the size of the gap between the two is about the same, and secure in place at the following torque.
Recommended tightening torque: 8.0 ± 0.4 N⋅m (82 ± 4 kgf⋅cm)
Turn on the Controller.
Press down Joint #3 while pressing the brake release switch, and then check the lower limit position. Do not lower the mechanical stop too far. Otherwise, the joint may not reach a target position.
Calculate the lower limit pulse value of the pulse range using the formula shown below, and set the value.
The result of the calculation is always negative because the lower limit Z coordinate value is negative.GX8-***2S (Z: -200 mm): Lower limit of pulse = (lower limit Z coordinate value)/40 × 131072 × (60/36)
GX8-***3S (Z: -330 mm): Lower limit of pulse = (lower limit Z coordinate value)/40 × 131072 × (60/36)Example: To lower the mechanical stop by 50 mm and change the lower limit Z coordinate value to "-150" with a 200 mm stroke
(-150)/40 × 131072 × (60/36) = -819200
Execute the following command in [Command Window].>JRANGE 3,-819200,0 'Sets the pulse range of Joint #3Using the Pulse statement (Go Pulse statement), move Joint #3 to the lower limit position of the pulse range that was set at low speed.
If the mechanical stop range is less than the pulse range, Joint #3 will hit the mechanical stop and an error will occur. When an error occurs, either change the pulse range to a narrower setting or extend the position of the mechanical stop within the limit.
Example: To lower the mechanical stop by 50 mm and change the lower limit Z coordinate value to "-150" with a 200 mm stroke
Execute the following command in [Command Window].>MOTOR ON 'Turns on the motor >SPEED 5 'Sets to low speed >PULSE 0,0,-819200,0 'Moves to the lower limit pulse position of Joint #3(In this example, all pulses except those for Joint #3 are "0". Substitute these "0" values with the other pulse values to specify a position where interference will not occur even when lowering Joint #3.)