Model HT1 Rotary Incremental Actuator

The Moog Type HT-1 Rotary Incremental Actuator is a new addition to the rotary actuator product line. It is a compact, closely integrated coaxial design composed of a small size permanent magnet stepper motor driving the output stage through a gear transmission consisting of a larger size harmonic drive. The actuator provides relatively high holding and running torque for its size. This actuator is optimized for low weight and relatively high torsional stiffness. Co-axial nesting of the motor and transmission drive elements gives the unit a small profile geometry. Nested new technology using coarse and fine potentiometers provide high resolution, telemetry with noise-free operation.



Key Features:

  • Compact and closely integrated coaxial design
  • Multi-stage speed reducer provides high gear ratio
  • Provides relatively high unpowered holding and running torque for its size
  • Optimized for low weight
  • Very fine output resolution
  • Zero backlash
  • High torsional stiffness



Parameter Units        Basis                Data         

Output Step Angle

Degrees Standard 0.0039
Steps per Revolution Steps Standard 92160
Max. Output Step Rate Steps/sec (Deg/sec) Maximum 400 (1.56)
Backlash Degrees Maximum <0.01°
Operating Temperature Range °C Maximum -70 to +105
Torsional Stiffness lb-in/Rad Minimum 125,000
Bending Stiffness lb-in/Rad Minimum 250,000
Axial Stiffness lb/in Minimum 88,000
Radial Stiffness lb/in Minimum 80,000
Output Load Capability Axial lbf Nominal 370
Tranverse lbf Nominal 370
Moment Lb-in Nominal 430
Fine Potentiometer Primary/Redundant 352° min. Electrical Travel 1% Linearity
Coarse Potentiometer Non-Redundant 192° min. Electrical Travel .25%
Output Torque Lb-in Minimum 300
Unpowered Holding Torque Lb-in Minimum 300
Powered Holding Torque Lb-in Minimum >450
Power Watts Maximum 10
Total Assembly Weight Lb Maximum 2.10
Inertia Capability kg-m2 Minimum 800 kg-m2

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