High Torque/Small Angle Rotary Incremental Actuator

The Moog High Torque Type 5 rotary incremental actuator is a compact, closely integrated design made up of two key elements: a motor and a multi-stage speed reducer. The motor is the heritage 1.5-degree permanent magnet stepper with a relatively high unpowered holding torque. The multi-stage speed reducer, consisting of an input planetary stage and a harmonic drive, offers a large reduction ratio (320:1), zero backlash, low weight, and high torsional stiffness. Coaxial nesting of the motor and transmission drive elements gives the unit an optimized geometry. All the electrical elements, such as motors and position sensors, can be redundant with little or no change in actuator envelope.



Key Features:

  • Multi-stage speed reducer provides high gear ratio
  • Relatively high unpowered holding torque
  • Low weight
  • Fine output resolution
  • Zero backlash
  • High torsional stiffness



Parameter Performance

Output Step Angle (degree)

Steps Revolution 76,800
Transmission Ratio 320
Motor Step Angle (degree) 1.5
Max. Output Step Rate (pps)  384
Max. Output Speed (deg/sec) 1.8
Torsional Stiffness

175,000 (lb-in/rad)

19,770 (N-m/rad) 

Shaft Load Capability Axial

840 (lbf)

3,750 (N)


1,800 (lbf)

8,036 (N) 


250 (ft-lb)

339 (N-m) 

Power Max. (Watts) @ 20.5 VDC 16
Inertial Capability

7376 (slug-ft2)

10,000 (Kg-m2)

Output Torque

1,000 (lb-in)

113 (N-m) 

Unpowered Holding Torque (min.)

550 (lb-in)

63 (N-m)

Powered Holding Torque (min.)

1800 (lb-in)

203 (N-m) 

Total Assembly Weight

7.10 (lb)

3.23 (Kg)

Related Markets


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