vss_crash_event

Pure-Dart, zero-dependency typed data classes for vehicle crash / impact events, modelled on the COVESA Vehicle Signal Specification (VSS) vocabulary.

VSS exposes the individual sensor primitives (airbag deployment, time-to-impact, brake-assist engagement) but has no single "crash event" signal. This package is the small aggregation layer edge developers consume: immutable value types, JSON round-trip, and an advisory derived severity — with no rendering or platform dependencies, so it runs anywhere Dart runs (Flutter, server, CLI, edge).

It is a Layer-0 parser/model package: it does not read VSS files or talk to a data broker; you map your data source into these types.

Install

dependencies:
  vss_crash_event: ^0.1.0

Usage

import 'package:vss_crash_event/vss_crash_event.dart';

final event = CrashEvent(
  timestamp: DateTime.now().toUtc(),
  obstacleDetection: ObstacleDetection(
    distanceMeters: 3.2,
    timeGapMs: 250, // time-to-impact
    warningType: ObstacleWarningType.crossTraffic,
  ),
  airbags: const [
    AirbagStatus(position: 'Row1.Pos1', isEnabled: true, isDeployed: true),
    AirbagStatus(position: 'Row1.Pos2', isEnabled: true, isDeployed: false),
  ],
  brakeAssist: const BrakeAssistStatus(absEngaged: true, ebaEngaged: true),
);

// Severity is derived from the readings unless you pass it explicitly.
print(event.severity);            // CrashSeverity.severe
print(event.deployedAirbagCount); // 1

// Serialize / deserialize.
final json = event.toJson();
final restored = CrashEvent.fromJson(json);
assert(restored == event);

VSS provenance

Each field is derived from a VSS signal. Field naming follows VSS conventions (units in the names) while staying idiomatic Dart.

CrashEvent and CrashSeverity are not native VSS signals — they are the aggregation and a derived convenience classification. CrashSeverity is advisory only; see CrashEvent.classifySeverity for the heuristic.

License

BSD 3-Clause. See LICENSE.