Control of Surface Configuration by Application of Concentrated Loads
The literature on active control of mirrors is briefly reviewed. An analysis method is formulated in which the surface quality of free axisymmetric spherical mirrors is controlled by actuators that produce concentrated forces or self-equilibr ating moment pairs. Normal displacement fields arising from unit actuator loads are generated with the use of thin shell theory by discretization of the radial coordinate and trigonometric expansion of the circumferential coordinate. It is found that local ripples caused by rather closely spaced self-equilibrating moment actuators are more pronounced than those caused by single force actuators, indicating that the former are not as suitable for surface quality control as the latter.