Speaker
Description
In 2021, a design was proposed as the foundational
metrology network for the forthcoming Scorpius linear
particle accelerator. By contrasting simulated network conditions
with empirical findings, this paper highlights the
benefits of predictive network design for novel or unfamiliar
operational environments. Located at the Nevada National
Security Site’s (NNSS) Primary Underground Laboratory
for Subcritical Experimentation (PULSE), the
Scorpius metrology network spans a total area of approximately
838 m2 and is 140 m at its maximum length. Due to
unique environmental constraints, the design of the network
was limited to two primary planes offset by 0.61 m.
To ensure compliance with project requirements, the design
of the network was completed using an iterative process
in which a Unified Spatial Metrology Network
(USMN) was modeled in SpatialAnalyzer®. The overall
goal of the simulation, in conjunction with other design parameters,
is to determine the total estimated error for placement
of the Scorpius beamline. The chosen figure of merit
(FOM), root mean square (RMS) of point error, was minimized
across several dozen permutations and provided an
associated overall point error of 25 μm. A parametric simulation
study was conducted on the monument network design
parameters, such as spacing, grid geometry, and
tracker placement, as means to optimize the monument network.
The simulated FOM was combined with several
other design inputs to calculate the estimated total error for
final placement of the Scorpius beamline. In April of 2026,
metrologists completed network measurements and analysis
of the as-built Scorpius metrology network. Based on
data collected and lessons learned from other parts of the
Scorpius project, additional monument nests were added to
the as-built design. Original estimates, derived from the institutional
knowledge of Subject Matter Experts (SMEs)
consulting on the project, projected the as-built configuration
would provide a FOM with a magnitude double that of
the simulation. The final as-built USMN analysis provided
a FOM of 17.8 μm, much smaller than expected given the
as-built real-world conditions.