Model Type 1 Rotary Incremental Actuator

The Moog Type 1 rotary incremental actuator is a compact, closely integrated design made up of two key elements, a stepper motor, and a harmonic drive speed reducer. The motor is a small angle permanent magnet stepper with high holding torque. The harmonic drive speed reducer offers a large reduction ratio, high load capability, low weight, zero backlash and high torsional stiffness. Coaxial nesting of the motor and harmonic drive elements allows use of large, relatively higher capacity output bearings and gives the unit a lower profile geometry.



Key Features:

  • Compact and closely integrated design
  • Low weight
  • Zero backlash
  • Optimized for low power consumption
  • Small angle permanent magnet stepper provides relatively high holding and running torque


Parameter Units Basis Data

Output Step Angle

Degrees Standard 0.0375
Steps per Revolution Steps Standard 9600
Max. Output Step Rate Steps/sec Maximum 400 (15)
Backlash Degrees Maximum Zero
Operating Temperature Range °C Maximum -50 to +80
Torsional Stiffness lb‐in/Rad   Minimum 20,000
Bending Stiffness lb‐in/Rad   Minimum 75,000
Axial Stiffness lb/in  Minimum 500,000
Radial Stiffness lb/in  Minimum 500,000
Output Load Capability Axial lbf  Nominal 1,080
Tranverse lbf  Nominal 1,080
Moment lb-in Nominal 415
Output Torque lb‐in  Minimum 70
Unpowered Holding Torque lb‐in  Minimum 20
Powered Holding Torque lb‐in  Minimum 70
Power Watts Maximum 4.5
Total Assembly Weight Lb Maximum 1.00

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Spacecraft Technologies

Moog is a proven leader in components, subsystems, and systems for spacecraft of all sizes, from smallsats to GEO spacecraft. Moog has been successfully providing spacecraft controls, inspace propulsion, and major subsystems for science, military, and commercial operations for more than 60 years.