Line-of-Sight Kinematics and Corrections for Fast-Steering Mirrors used in Precision Pointing and Tracking Systems



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SPIE-Int Soc Optical Engineering


Fast steering mirrors, or FSMs, have been used for several decades to enhance or augment the performance of electro-optical imaging and beam-steering systems in applications such as astronomy, laser communications and military targeting and surveillance systems. FSMs are high-precision, high-bandwidth electro-mechanical mechanisms used to deflect a mirror over a small angular displacement relative to the base it is mounted on which is typically a stabilized gimbal or other primary pointing device. Although the equations describing the line-of-sight kinematics derive entirely from the simple plane-mirror law of reflection, they are non-linear and axis-coupled and these effects increase as the FSM angular displacement increases. These inherent non-linearities and axis-coupling effects can contribute to pointing errors in certain modes of operation. The relevant kinematic equations presented in this paper can be used to assess the magnitude of the errors for a given application and make corrections as necessary.



Mirrors, Line of sight, Kinematics, Pointing, LAser Detection And Ranging (LADAR)


©2014 Society of Photo-Optical Instrumentation Engineers. One print or electronic copy may be made for personal use only. Systematic reproduction and distribution, duplication of any material in this paper for a fee or for commercial purposes, or modification of the content of the paper are prohibited.


Hilkert, J. M., G. Kanga, and K. Kinnear. 2014. "Line-of-Sight Kinematics and Corrections for Fast-Steering Mirrors Used in Precision Pointing and Tracking Systems." Proceedings of SPIE, Airborne Intelligence, Surveillance, Reconnaissance (ISR) Systems and Applications Xi 9076: 90760F.