In early 2001, Boeing-SVS, Inc. (BSVS) began an internal research and development (IR&D) project, dubbed the dual
line of sight (DLOS) experiment, to perform risk reduction on the development of the control systems and mode logic
for a strategic laser relay mirror system. The DLOS experiment uses primarily commercial off-the-shelf (COTS)
hardware and real-time system software, plus internally-designed gimbals and flexible mode logic tools to emulate a
scalable relay mirror engagement. The high-level, nominal engagement sequence begins with the laser source gimbal
establishing a line of sight with the relay receiver gimbal by closing passive acquisition and fine-tracking loops.
Simultaneously, the receiver gimbal closes passive acquisition and fine-tracking loops on the laser source, and a low-power,
660-nanometer alignment laser is propagated through the system. Finally, the transmitter gimbal closes passive
acquisition and fine-track loops on a target, and the system propagates a simulated high-energy laser (HEL) on that line
of sight onto target models. In total, the DLOS experiment closes 28 control loops. For the strategic scenario, a model
rocket target is illuminated with a light-emitting diode and tracked by the BSVS advanced reconfigurable trackers using
a centroid algorithm. The strategic scenario also uses a 532-nanometer laser to close an active track loop using a Linux
tracker. To better align with our business capture strategy, the emphasis of the experiment in 2005 has shifted to
emulating an urban tactical engagement and developing weapon system operator consoles.