Typically, beam steering mirrors have been custom designed for specific performance and form factor requirements for each new program. In many cases, the requirements are stressing in just one or two areas, such as, bandwidth or travel. Hughes has developed and tested a universal beam steering mirror design, called the Hughes Beam Steering Mirror (HBSM), that simultaneously provides large angular mechanical travel in two areas (+/- 3.5 degree(s)), high bandwidth (1 kHz), high acceleration (1200 rad/sec2), low noise (< 100 nrad), with a 5 inch clear aperture reactionless mechanism in a compact envelope (< 5' X 5' X 7'). These performance parameters combined meet the demanding agile steering mirror requirements of many SDI programs, while satisfying the requirements of systems that may require only a subset of these parameters. One of two key distinctions of the HBSM is the cross blade flexure. The cross blade flexure provides low stiffness in the two desired tilt degrees of freedom, while providing very high stiffness in all other degrees of freedom. This allows for a simple mirror control law that does not require active control over other degrees of freedom, and provides infinite cycle life over a +/- 3.5 degree(s) travel range. The second unique design distinction is the slotted bobbin voice coil actuator. This design was developed to counter the effects of a metallic bobbin when high bandwidth, displacement, and acceleration are simultaneously required. This paper will present the HBSM design, the performance analysis for the cross blade flexure, the design theory for the slotted bobbin, and performance data on the HBSM mechanism.
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