In some applications, moment actuators provide a competitive altemate approach to the conventional piston type of actuators. A piezo-electrlc or a simIlar device placed between two posts on the back surface of a deformable mirror constitutes one type of moment actuators. A dosed form solution of the blharmonlc equation of Kirchoffs thin plate theory Is obtained by the classical method of boundary value problems of linear elastomechanics and presented in this paper for the influence function of an arbitrarily located and oriented moment actuator of the above type on the back of a flat circular deformable mirror. The solution covers both radial and tangential moments. The results clearly show their global character in contrast to those for the piston type actuators with high stiffness. An application of this function to the design of a 30-actuator circular deformable mirror with moment actuators, related hardware, and test results has been reported elsewhere1.
Pravin K. Mehta,
"Moment-actuator influence function for flat circular deformable mirrors", Proc. SPIE 1303, Advances in Optical Structure Systems, (1 October 1990); doi: 10.1117/12.21494; https://doi.org/10.1117/12.21494