GENSYS Railway Dynamics (.calc, .sub, .geom, .trax, .wheel)

ModelScript provides native support for GENSYS, the world standard railway vehicle dynamics, track-vehicle interaction, and vehicle running safety simulation environment.

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Capabilities

• Command Deck Parsing: Full support for .calc, .run, and .sub structured card records defining rigid car bodies, bogies, wheelsets, and primary/secondary spring-damper couplings.
• Track Geometry & Irregularities: Ingests .geom and .trax files with longitudinal distance, horizontal/vertical irregularities, cant (crosslevel), and curvature $1/R$.
• Kalker FASTSIM & Polach Contact Mechanics: Discretizes rolling contact ellipses into elastic/slip zones to compute tangential creep forces ($F_x$, $F_y$) and spin moment ($M_z$) with non-linear saturation.
• WebAssembly Contact Mechanics Kernel:
  • High-performance AssemblyScript linear memory kernel (contact.wasm) executing Kalker FASTSIM 8-slice strip integration and Polach creep mechanics.
  • High-throughput multi-axle batched contact patch solvers (batchFastsim, batchPolach).
• EN 14363 / UIC 518 Vehicle Acceptance: Automated safety evaluation of the derailment quotient ($Y/Q\le 0.8$) and Prud'homme lateral track shifting force limits.
• Ride Comfort & Equivalent Conicity: Evaluates Sperling ride index ($W_z$) and wheel-rail equivalent conicity ($\lambda$).
• DAE Lowering & MultiBody Export: Direct lowering to linear-memory DAEBuilder and automated projection to standard Modelica.Mechanics.MultiBody components.
• FMI 2.0 / 3.0 Co-Simulation FMU Export: Packages complete vehicle and track dynamics into standalone .fmu archives with standardized vehicle states, running safety outputs, and C co-simulation wrapper runtime.
• Interactive 3D Viewport: WebGL/Three.js 3D visualization rendering carbody shells, front/rear bogie frames, wheelsets, and primary/secondary spring dampers with orbit controls.

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CLI Usage

# Pre-flight linting of GENSYS vehicle deck
msx gensys lint coach.calc

# Direct DAE simulation in WebAssembly arena with CSV trajectory export
msx gensys simulate coach.calc --stop-time=5.0 --step=0.005 --out=results.csv

# Export vehicle dynamics as an FMI 2.0/3.0 Co-Simulation FMU
msx gensys to-fmu coach.ins --out=PassengerCoach.fmu

# Export to standard Modelica MultiBody model
msx gensys to-modelica coach.calc --out=PassengerCoach.mo

# Verify EN 14363 running safety criteria
msx gensys verify --y-force=28.5 --q-force=82.0 --axle-load=160.0

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Benchmarks

• Manchester Benchmark for Railway Vehicle Dynamics (languages/gensys/testsuite/ManchesterBenchmark.ins):
  • Standard passenger coach benchmark (Iwnicki et al.): 32-ton passenger carbody, two 3.2-ton bogie frames, four 1.8-ton wheelsets running at $V=40\text{ m/s}$ (144 km/h).
  • Validates secondary and primary suspension settling dynamics, 8-patch FASTSIM contact in WASM, and EN 14363 / UIC 518 derailment safety limits.

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MCP Tools

AI agents interacting via the ModelScript MCP server have access to:

• gensys_lint: Validates body parameters, mass positivity, and suspension couplings.
• gensys_verify_en14363: Assesses derailment quotient and lateral track shift limits.
• gensys_fastsim: Computes rolling contact tangential creep forces and adhesion saturation.

Diagnostic Rules

6 rules5 error1 warning Run with msx gensys lint

Code	Rule	Severity	Message
G1001	invalid-body-mass	error	Body '<name>' has non-positive mass (<mass> kg).
G1002	non-positive-inertia	error	Body '<name>' has non-positive principal inertia tensor components.
G1003	dangling-body1-reference	error	Coupling '<name>' references unknown body1 '<body1>'.
G1004	dangling-body2-reference	error	Coupling '<name>' references unknown body2 '<body2>'.
G1005	invalid-track-gauge	error	Track specification defines non-positive or unphysical gauge (<gauge> m).
G1006	unclosed-rail-profile	warning	Wheel-rail contact profile '<profileName>' curve has discontinuous slope or is unclosed.

Generated from languages/gensys/src/errors.ts. All languages →