Linear Electromechanical Actuator Research Articles

Electromechanical linear actuators for Fourier transform spectrometers: a concept for extended range, high-resolution, solid-state actuators

A piezoelectric effect device is reported that provides highly controllable, extended linear motion in an easily usable package. Recent advances in materials, materials processing, and piezoelectric mechanics have been synthesized to demonstrate an all-solid-state electromechanical actuator for Fourier transform spectrometer mirror position control. This actuator is inherently linear and is therefore a major improvement in efficiency, size, and mass over motors and lead screws, which require conversion from rotary to linear actuation. Velocity control of 1% has been demonstrated over a range of 0.5 cm at a velocity of 1 cm/s. Scaling to a range of 4 cm and a velocity of 4 cm/s is discussed and currently appears feasible.

Bond graph models for electromagnetic actuators

Rotary and linear electromechanical actuators are often used as the effectors for controlled systems and they often are important contributors to the dynamic response of the complete system. A generalized bond graph model for such actuators is developed which represents the three major types of forces or torques generated when coils, low reluctance elements and permanent magnets interact. A wide variety of actuators can bemodeled by versions of the basic bond graph which is simplifiable when some effects are neglible. The bond graph aids in understanding algebraic manipulations necessary to put the constitutive laws into forms compatible with other elements of the system for simulation or analysis.

Electromechanical Actuation Technology for the All-Electric Aircraft

Electromechanical actuation is a critical element that must be developed and verified to make the all-electric aircraft a viable concept. For several years the Flight Control Division of the Air Force Wright Aeronautical Laboratories has sponsored activities to demonstrate the credibility of electromechanical actuation systems (EMAS) for primary flight control actuation functions. The foundation for these EMAS activities and several electromechanical actuation development programs are described here. One involves the design, fabrication, and laboratory test of a rotary, hingeline electromechanical actuator. Another involves the development and flight test demonstration of a linear electromechanical actuator for controlling an aileron of a C-141 aircraft. A third involves the design and development of a linear electromechanical actuator for missiles having severe performance, temperature, and volumetric requirements. In addition, a brief summary of the results from two aircraft actuation trade studies compare the baseline (conventional) hydraulic flight control system with an all-electric airplane concept including quantitative comparisons of weight, reliability and maintainability, and life cycle costs.