6. Specifications

The following subsections provide data on the various specifications for the Robotiq 2-Finger 85 and 140 Adaptive Grippers.

• Section 6.1 lists the technical dimensions of the Grippers
  • Dimensions for custom (blank) coupling
  • Dimensions of all available couplings
  • Dimensions for custom fingertip
  • Dimensions of all available fingertips
• Section 6.2 presents the mechanical specifications of the Grippers.
• Section 6.3 gives electrical specifications for the Grippers.

6.1. Technical dimensions

The 2-Finger 85 and 2-Finger 140 share the same basic chassis and thus have the same technical dimensions for everything except the fingers. Figure 6-1 represents the Robotiq 2-Finger 85 Adaptive Robot Gripper's dimensions with axis X, Y, Z and origin referenced for finger motion. Figure 6-3 will show the equivalent with 140 mm fingers (2-Finger 140).

Fig. 6-1: 2F-85 general dimensions (opened).

As mentioned in the figure above, height and width of the fingers vary with opening position. Figure 6-1 represents the 2F-85 Gripper in the opened position (position request = 0), while Figure 6-2 represents the 2F-85 Gripper in the closed position (position request = 255).

Fig. 6-2: 2F-85 dimensions (closed).

Fig. 6-3: 2F-140 general dimensions (opened).

Fig. 6-4: 2F-140 dimensions (closed).

As mentioned in the figure above, the height and width of the fingers vary with opening position. Figure 6-3 represents the 2F-140 Gripper in the opened position (position request = 0), while Figure 6-4 represents the 2F-140 Gripper in the closed position (position request = 255).

6.1.1. Couplings

The Robotiq 2-Finger Adaptive Robot Gripper requires a coupling provided by Robotiq to operate. The coupling is mandatory since it integrates electronics and electrical contacts.

6.1.1.1. Blank coupling

Below are the dimensions of the blank coupling, AGC-CPL-BLANK-002 (refer to the Spare Parts, Kits and Accessories section), available to create a custom bolt pattern. Blue section can be fully customized (holes can be place in any part of this section) while the grey section can only be worked to a depth of 3 mm.

Fig. 6-5: Blank coupling AGC-CPL-BLANK-002 workable area dimensions.

6.1.1.2. Coupling for ISO 9409-1-50-4-M6

Bolt pattern for coupling AGC-CPL-062-002 (refer to the Spare Parts, Kits and Accessories section) is compatible with :

• 50 mm pitch circle diameter :
  • (4) M6-1.0 low head socket cap screw clearance
  • (1) M6 indexing pin
  • ISO 9409-1 standard 50-4-M6

Fig. 6-6: Coupling for ISO 9409-1-50-4-M6.

6.1.1.3. Coupling for ISO 9409-1-31.5-4-M5

Bolt pattern for coupling AGC-CPL-063-002 (refer to the Spare Parts, Kits and Accessories section) is compatible with :

• 31.5 mm pitch circle diameter :
  • (4) M5-0.8 low head socket cap screw clearance
  • (1) M5 indexing pin
  • ISO 9409-1 standard 31.5-4-M5

Fig. 6-7: Coupling for ISO 9409-1-31.5-4-M5.

6.1.1.4. Coupling for ISO 9409-1-40-4-M6

Bolt pattern for coupling AGC-CPL-064-002 (refer to the Spare Parts, Kits and Accessories section) is compatible with :

• 40 mm pitch circle diameter :
  • (4) M6-1.0 low head socket cap screw clearance
  • (1) M6 indexing pin
  • ISO 9409-1 standard 40-4-M6

Fig. 6-8: Coupling for ISO 9409-1-40-4-M6.

6.1.1.5. Coupling for PCD 56 with 8 x M4

Bolt pattern for coupling AGC-CPL-065-002 (refer to the Spare Parts, Kits and Accessories section) is compatible with :

• 56 mm pitch circle diameter :
  • (8) M4-0.7 low head socket cap screw clearance
  • (1) M4 indexing pin
  • 62 mm diameter internal insert

Fig. 6-9: Coupling for PCD 56 mm with 8 x M4 clearance.

6.1.1.6. Coupling for PCD 56 with 6 x M4

Bolt pattern for coupling AGC-CPL-066-002 (refer to the Spare Parts, Kits and Accessories section) is compatible with:

• 56 mm pitch circle diameter:
  • (6) M4-0.7 low head socket cap screw clearance
  • (1) M6 indexing pin
  • 42 mm diameter external insert

Fig. 6-10: Coupling for PCD 56 mm with 6 x M4 clearance.

6.1.1.7. Coupling for PCD 60 with 4 x M5

Bolt pattern for coupling AGC-CPL-067-002 (refer to the Spare Parts, Kits and Accessories section) is compatible with :

• 60 mm pitch circle diameter :
  • (4) M5-0.8 low head socket cap screw clearance
  • (1) M5 indexing pin
  • 34 mm diameter external insert

Fig. 6-11: Coupling for PCD 60 mm with 4 x M5 clearance.

6.1.1.8. Coupling for PCD 63 with 6 x M6

Bolt pattern for coupling AGC-CPL-068-002 (refer to the Spare Parts, Kits and Accessories section) is compatible with :

• 63 mm pitch circle diameter :
  • (6) M6-1.0 low head socket cap screw clearance
  • (2) M6 indexing pins

Fig. 6-12: Coupling for PCD 63 mm with 6 x M6 clearance.

6.1.2. Fingertips

The contact grasp points for the Robotiq 2-Finger Adaptive Robot Gripper are its two fingertip pads and palm pad. Many fingertips are available from Robotiq (refer to the Spare Parts, Kits and Accessories section). The user can customize their own fingertips from blanks or create them from scratch. The figure below represents the distal phalanx (which acts as the fingertip holder) the permanent, non customizable part of the Gripper finger on which the fingertip must be mounted.

Custom fingertip designs must abide by the following:

• Fingertip must not exceed 100 mm in height from the fingertip's base.
• Fingertip must not exceed 100 mm in width from the fingertip's base (refer to Y axis from figure 6-18).
• Refer to the Mechanical specifications section to evaluate the grasp force according to your fingertip design.
• Applied forces to the gripper must not exceed moment and force limits detailed in the Moment and force limits section.

Fig. 6-13: Distal phalanx for holding standard or custom fingertips.

6.1.2.1. Flat silicone fingertip

The figure below represents a flat silicone fingertip AGC-TIP-204-085 (2F-85) and AGC-TIP-420-140 (2F-140); please refer to the Spare Parts, Kits and Accessories section. This fingertip has a flat silicone surface with an optimal friction coefficient for picking objects while the other surface will mount onto the fingertip holder shown in the Fingertips section.

Fig. 6-14: Flat silicone fingertip AGC-TIP-204-085

Fig. 6-15: Flat silicone fingertip AGC-TIP-420-140

6.1.2.2. Grooved fingertip

The figure below represents the available grooved fingertip AGC-TIP-205-085 (2-Finger 85) and AGC-TIP-421-140 (2-Finger 140); please refer to the Spare Parts, Kits and Accessories section. This fingertip has a grooved surface with an optimal shape for picking cylindrical objects (with its horizontal and vertical grooves) while the other surface will mount onto the fingertip holder shown in the Fingertips section.

Fig. 6-16: Grooved fingertip AGC-TIP-205-085

Fig. 6-17: Grooved fingertip AGC-TIP-421-140

6.2. Mechanical specifications

¹Repeatability is defined as the positional deviation resulting from the average displacement determined when picking an object with a parallel grasp using standard silicone fingertips. For more details see the blog.robotiq.com article on repeatability. Position repeatability varies depending on the product wear and operating conditions. The presented values are typical for the newly-manufactured products.

²Resolution is the increment modified from a 1 bit difference of position/speed/force request (from 0 to 255).

6.2.1. Payload and force

Actuation force model used to calculate recommended payload is described in the figure below, the user must not exceed the force and torque limits:

Fig. 6-18: Actuation force on the fingertip of the Adaptive Gripper 2-Finger (see charts below for 2-Finger 85 and 2-Finger 140 force).

Fig. 6-19: Grasp force in the Y and Z axis for the 2-Finger 85 and 2-Finger 140.

As defined in figure 6-18, the weight that can be lifted is defined by :

• F is the force that is applied to the load by the Gripper.
• Cf is the friction coefficient between the fingertip and the object load.
• Sf is a safety factor to be determined by the robot integrator.

6.2.1.1. Friction grasp and form-fit grasp

Maximum payload by grasp type

6.2.2. Equilibrium Line

Equilibrium line position (explained in the General Presentation section) is detailed in the figure below, where:

• q is the opening angle between the Gripper proximal bar and center line
• d is the distance between the bottom of the finger pads and the equilibrium line as seen on the Z axis in figure 1-5.

Fig. 6-20: Position of the Gripper equilibrium line according to the opening angle for 2-Finger 85 and 2-Finger 140 options.

6.2.3. Center of mass, tool center point and moment of inertia

Coupling is included when Gripper is not mounted on the Camera. Dual Gripper adapter plate included where appropriate.

The moment of inertia are calculated for a configuration where the fingers are fully open. Here is the approximate moment of inertia matrix for the Gripper:

Fig. 6-21: Robotiq 2-Finger inertia matrix.

6.2.4. Moment and force limits

The 2-Finger Adaptive Gripper has maximum moments and force limit. The listed moments and forces are independent to the force applied by the Gripper itself on it's payload. For payload calculation, refer to the Mechanical specifications section.

* Moments in x and y are calculated from the base of the fingertips as shown in figure 6-19.

Example usage of the listed limit :

• After picking it's normal payload, the robot can use the 2-Finger 85 Gripper to apply up to 50 N of force in any direction. Applying more then 50 N could damage the Gripper or result in payload loss.
• The Gripper can pick a screwdriver and apply 3 Nm of torque to screw ( such moment would be in the Z axis).

6.3. Electrical specifications