Attitude Control System Actuation
project name

Attitude Control System Actuation

For Guided Munition

description

Linear electromechanical actuator (EMA) design for a guided munition block upgrade.

Problem Statement
Ingenium Aerospace’s customer requested the development of an ACS system through a critical design review (CDR) level including detailed design documentation.  The system had to operate at an extremely high speed and altitude during a long distance flight regime.  The linear actuation solution required high, closed loop, small amplitude frequency response, and low backlash, tight packaging constraint and the ability to provide ample output force while operating at high speed under extreme environmental conditions.

Solution
The ACS actuators provide an axial force to extend and retract a valve pintle, to regulate valve mass flow.  The actuator created force by converting torque from an electric motor through reduction gearing and a rotary-to-linear coupling mechanism.  The ACS requires sensors to measure vehicle orientation, actuators to apply the forces or torques needed to re-orient the vehicle to a desired attitude, and algorithms to command the actuators to the required position.
Ingenium’s solution features a custom wound brushless DC motors, a custom gearbox and a rack and pinion linear output. Ingenium’s product engineering team optimized the gear ratios using MATLAB / Simulink models. This effort required a defined closed loop frequency response at low amplitude to achieve the required performance backlash. This very small and tightly-packaged product weighs less than 0.5 lb.

Results & Outcome
Ingenium Aerospace delivered a detailed design and documentation package for this product. The effort included all the analysis, models, presentation, compliance matrices, trade studies and detailed drawings to fabricate the actuator, all of which was completed in less than five months.