Naval Steering and Diving Control Actuation System (SDCAS)


The Steering and Diving Control Actuation System (SDCAS) controls the four (4) main control surfaces, or fins, of an unmanned underwater vehicle (UUV). The system receives digital commands over a serial bus (multiple protocols are available) and power from either AC or DC bus power. SDCAS drives each fin to the master controllers commanded position independently. The system also outputs various system monitor parameters, warnings, and faults. This includes motor temperatures, fin lock status, bus current and voltage, and communication status with each actuator.



Key Actuator Features

  • Customizable output torque, slew angle, and speed 
  • BLDC motor provides highly reliable, acoustic sensitive actuation 
  • Failsafe options are customizable for specific applications 
  • Output shaft lock solenoids available 
  • Pressure compensated housings available for application specific depth requirements 
  • Multiple position feedback options available, including redundant options

Key Controller Features

  • Integrated power supply customizable for various input power 
  • Multiple fieldbus communication protocols available 
  • Position, velocity, or torque loop closure options 
  • Customizable switching frequencies and communication baud rate 
  • Customizable failsafe options for communications loss 
  • Multiple feedback device options available

Actuator Performance Summary


Features Specifications
Stroke ± 30° 
Stall Torque >500 in-lbs.
No load speed >20°/s
Loaded speed >15°/s @ 300 in-lbs.
Rated power 0.012 HP
Peak motor current 0.7 A
Actuator weight 19 lbs. 
Max braking torque (wave slap) 1000 ft-lbs.
Operating temperatures 28° - 85°F
Pressure rating >5000 ft

Controller Performance Summary


Features Specifications
Supply voltage 8 – 300 VDC
Communications interface Multiple options
Position feedback Resolver, encoder, HED 
Controller weight ~33 lbs.
Operating temperatures 28° – 85°F 
Pressure rating >5000 ft