ASAM OpenSCENARIO Autonomous Driving (.xosc, .osc)

@modelscript/openscenario (languages/openscenario) provides zero-regex XML and domain DSL parsing, dynamic scenario orchestration, Time-To-Collision (TTC) monitoring, Mobileye Responsibility-Sensitive Safety (RSS) margin verification, linear DAE lowering, and Modelica 3.x projection for ASAM OpenSCENARIO 1.x & 2.0 autonomous vehicle validation scenarios.

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Supported Extensions & Standards

Extension	Format	Description
.xosc	ASAM OpenSCENARIO 1.x XML	XML-based scenario description (storyboards, entities, maneuvers, triggers, actions)
.osc	ASAM OpenSCENARIO 2.0 DSL	Domain-specific declarative and imperative scenario language for AV test generation

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Key Capabilities

1. Dynamic Scenario Orchestrator

• Executes storyboard acts, maneuver groups, and event-condition-action triggers across moving entities (ego vehicle, NPC traffic vehicles, pedestrians, cyclists):
  • Triggers: Simulation time, relative longitudinal distance, headway time, velocity thresholds, reach position.
  • Actions: Longitudinal speed change ($a(t)$), lane change ($\dot{y}(t)$), lateral offset, waypoint trajectory following.
• Couples directly with analytical clothoid road geometry imported from ASAM OpenDRIVE (@modelscript/opendrive).

2. Time-To-Collision (TTC) & Mobileye RSS Safety Verification

• Continuously evaluates kinematic safety margins between the autonomous vehicle ($E$) and surrounding traffic ($T$):
  • Time-To-Collision (TTC):$$\text{TTC}=\frac{x_{\text{lead}}-x_{\text{ego}}}{v_{\text{ego}}-v_{\text{lead}}}(\text{for }{v}_{\text{ego}}>v_{\text{lead}})$$
  • Mobileye RSS Longitudinal Safe Distance:$$d_{\text{min,long}}={[v_r\cdot \rho +\frac{1}{2}{a}_{\text{max,acc}}{\rho }^2+\frac{(v_r+\rho a_{\text{max,acc}}{)}^2}{2a_{\text{min,brake}}}-\frac{v_f^2}{2a_{\text{max,brake}}}]}_{+}$$where $\rho$ is sensor reaction time, $a_{\text{max,acc}}$ is maximum acceleration, and $a_{\text{min,brake}}$ is minimum emergency braking deceleration.

3. Direct DAE Lowering

• Lowers entity kinematics (position, heading $\psi$, velocity $v$, acceleration $a$) into @modelscript/runtime's DAEBuilder linear memory arena.
• Enables co-simulation with vehicle multibody dynamics (@modelscript/simpack, @modelscript/adams) and powertrain control loops (@modelscript/simulink).

4. Bidirectional Modelica 3.x Projection

• Projects scenario storyboards into Modelica vehicle tracking and path-following controllers.

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Pre-Flight Diagnostics

The OpenSCENARIO analyzer validates actor references, trigger reachability, and safety margins:

10 rules7 error3 warning Run with msx openscenario lint

Code	Rule	Severity	Message
M8501	dangling-entity-reference	error	Entity '<entityName>' referenced in '<contextName>' is not defined in Entities catalog.
M8502	unsatisfiable-trigger	warning	Trigger condition '<conditionName>' is unsatisfiable: <reason>.
M8503	unreachable-road-position	error	Road position specifies invalid road ID '<roadId>' or lane index '<laneId>'.
M8504	cyclic-event-trigger	error	Circular trigger condition detected between event '<eventA>' and event '<eventB>'.
M8505	missing-ego-entity	error	Scenario does not define an autonomous vehicle under test ('ego' vehicle).
M8506	negative-speed-target	error	Speed action '<actionName>' specifies negative target velocity '<speed>' m/s.
M8507	excessive-deceleration	warning	Action demands deceleration '<decel>' m/s² for '<entityName>', exceeding vehicle limit '<limit>' m/s².
M8508	imminent-collision-initial-state	error	Initial positions for '<entityA>' and '<entityB>' violate collision envelope (distance: <value> m).
M8509	empty-maneuver-group	warning	Maneuver group '<groupName>' specifies no actors or no maneuvers.
M8510	invalid-condition-delay	error	Trigger condition '<condName>' specifies negative activation delay '<delay>' s.

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

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CLI Usage

# Inspect entities, maneuvers, and triggers in an OpenSCENARIO file
msx openscenario inspect HighwayCutIn.xosc

# Run pre-flight linting and trigger feasibility checks
msx openscenario lint HighwayCutIn.xosc

# Simulate scenario execution and evaluate TTC / RSS safety margins
msx openscenario simulate HighwayCutIn.xosc --duration=10.0

# Lower scenario kinematic equations to ModelScript linear DAE arena
msx openscenario to-dae HighwayCutIn.xosc

# Project into Modelica 3.x vehicle kinematics model
msx openscenario to-modelica HighwayCutIn.xosc -o ScenarioSimulation.mo