FIRGELLI APPLICATION CALCULATOR
Robot Arm Actuator Calculator
Size three actuators for a robot shoulder, elbow and hinged gripper. Set each joint separately, then view the complete arm.
Start your calculation ↓
How the shoulder, elbow and gripper work
Two lifting joints carry a gripper with one hinged moving finger and one fixed finger. Each actuator has an independent base X/Y, rod pin along its driven member, rod pin perpendicular offset and opening/closing angles. All joint angles are relative to the supporting member. Shoulder and elbow moments include every downstream moving weight, the fixed gripper housing and the payload at the fixed-finger contact point. The fixed finger supports the payload. The moving finger is sized for its own weight plus the entered gripping force normal to that finger at the contact distance. Gripping force is internal to the gripper and is not added as an external arm load. Motion follows the three entered angle ranges together. This is a planar steady-motion estimate; dynamic acceleration, collisions and grip retention are not modeled.
Measure each actuator mounting
Select a joint and enter its link length, weight and opening and closing angles. Measure the actuator base X and Y from that joint pivot. Measure the moving rod pin along the driven link and enter any perpendicular bracket offset. Positive and negative coordinates place the pins on either side of the reference axes.
For the gripper, set the moving finger length, contact distance and required gripping force. Enter the payload and fixed gripper body weights separately. The calculator assumes the fixed finger supports the payload; gripping force is specified independently.
Compare actuators for each joint
Shoulder, elbow and gripper each have their own peak force, required stroke and mounting-length results. Select a joint before opening Actuator matches. Dimensions and ratings are checked before prioritizing Super Duty, Utility and C-Series options. Industrial actuators take priority where the load or required force exceeds 450 lbf.
Use the selected-joint view to inspect the mounting pins and angle guides, or View whole arm to watch all three drives. Download PDF includes the entered measurements and all three joint results.