Ultra Fine Angle Rotary Incremental Actuators

Along with the standard Type 3 and Type 5, the Moog Type3-EF and Type 5-EF Rotary Incremental Actuators are new additions to the rotary incremental actuator lines. The design is based on a recently developed ultra-fine (sub-degree) step angle permanent magnet stepper motors which in combination with the standard harmonic drive gear reducers produces extra fine output step resolution. The new line of actuators offers quiet operation, low weight, zero-backlash, and high output torsional stiffness. All electrical elements, such as motors and position sensors, can be redundant with little or no change in actuator envelope.



Key Features:

  • Ultra-fine proprietary permanent magnet stepper motors
  • Very fine output resolution provides fine pointing
  • Quiet operation
  • Low weight
  • Zero backlash
  • High torsional and moment stiffness


Characteristic Performance / interfaces                              

Output Step Angle

0.0015 0.001
Steps Per Revolution 240,000 360,000
Transmission Ratio 160:1 200:1
Motor Step Angle (degree)  0.24 0.2
Max. Output Step Rate (pulses/sec) 1000 800
Max. Output Speed (deg/sec) 1.5 0.8
Running Torque (lb-in)  250 325
Un-powered Holding Torque (lb-in)  80 100

Related Markets


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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.