AGI (Analytical Graphics)

Analytical Graphics Inc. (AGI), founded in 1989 in Exton, Pennsylvania and acquired by Ansys in 2021, was the developer of Systems Tool Kit (STK) — the world's most widely used commercial software for space mission design, analysis, and operations — which has become the de facto industry standard environment for modeling spacecraft orbits, satellite coverage, ground station contacts, sensor field-of-view analysis, and space situational awareness across 50,000+ licensed users at government agencies, defense contractors, and commercial space operators globally.

STK's core capability is high-fidelity orbital mechanics modeling: propagating satellite positions over time using SGP4/SDP4 propagators for TLE-based objects, J2/J4 perturbation models for precise mission analysis, or numerical integration for high-accuracy trajectory design. Around this orbital core, STK layers sophisticated analysis tools: coverage analysis (which ground regions are visible to satellite sensors for how long during each pass), link budget analysis (antenna gain patterns, signal-to-noise ratio calculations for communications links), rendezvous and proximity operations modeling, constellation design optimization, radar cross-section modeling, and conjunction analysis for space traffic management.

STK has been used by NASA for mission planning on virtually every major space program including the Space Shuttle, ISS, lunar missions, and Mars rovers; by the NRO and intelligence community for satellite operations and coverage planning; by the Air Force Research Laboratory (AFRL) for space control mission analysis; and by commercial satellite operators for contact scheduling, coverage optimization, and regulatory filings. Its companion software ODTK (Orbit Determination Tool Kit) provides the statistical orbit determination capabilities used for precise satellite tracking and collision avoidance.

AGI's acquisition by Ansys integrated STK's space domain physics-based modeling with Ansys's broader engineering simulation platform (structural, thermal, electromagnetic, fluid dynamics analysis), creating a comprehensive spacecraft design and analysis environment that can model both the space mission environment and the spacecraft physics within a single product ecosystem.