Applied Full-Car dynamics and physical Motion

One Motion experience in VehicleLab 2.1.1

Quarter-Car, Half-Car, Full-Car Ride, spatial Full-Car and coupled Full-Car share Play, Pause, Restart, time, speed and the engineering viewport. Each model keeps its own physical pose adapter. Expand Engineering Details for coordinates and provenance, and Model Assumptions for display conventions. Camera and appearance controls never change a result.

Coupled dynamics retains its operation-preserving TypeScript reference with exact-input reuse. The accepted ML66 physical model, continuation path and numerical tolerances remain unchanged. Its separately identified source and independent checks are available in the ML67 qualification summary. Scientific records retain their generating kernel's release metadata; the Studio product release is independent of those frozen identities.

Prepare the applied physical vehicle

In Studio → Vehicle, open Model fidelity & compatibility. Supply source-bound physical complements, check compatibility and prepare the physical definition. The exact default educational example is available only for its matching assembly. Changing mass, geometry or other physical inputs requires explicit review and repreparation.

The supported subset has mirrored Double-Wishbone geometry, a complete central body inertia tensor, physical racks and tie rods, axisymmetric rotors, installed springs/dampers and four explicit combined-slip tires. Missing inputs stay missing. MacPherson dynamics and unreconstructible linear geometry are unsupported; no generic replacement is inserted.

Select fidelity and run the actual definition

Choose Use prepared vehicle in Test, or select Full-Car Coupled Dynamics — 14 DOF in Full-Car Test. Without a qualified current preparation, Run is unavailable and the page explains how to prepare. Full-Car Ride — 7 DOF remains accessible. Generic Advanced Analysis retains its separate reference vehicles.

Choose coast, braking, smooth steering step, steering pulse or combined steering/braking. The historical flat presets use a bounded forward-moving, four-loaded-contact domain on flat compliant support. Signed rack displacement follows the actual linkage; positive rack need not mean positive wheel heading. Initial rack is zero; smooth prescribed inputs advance from the actual assembled equilibrium.

In Numerical tolerances and limits, choose the execution backend explicitly. TypeScript remains the permanent reference option. Native C++/WebAssembly is the default for new supported 14-DOF studies and runs the same moving-rack mechanics, tires, RK4/RK45 stages and output recording inside a local Worker. One-time equilibrium and rolling initialization remain TypeScript. Native results identify their actual backend, source, ABI and module fingerprints, and use a separately versioned record with the same physical channels and shared Motion.

Inspect steering and suspension

Camera controls share 3/4, Side, Front, Rear, Top, Suspension and Free concepts with Full-Car Ride. Applied and spatial models also offer Chase and Fixed. Choose Suspension and a corner to follow its actual solved assembly without rerunning the simulation. Fit, Reset and Expand retain the current physical time.

Choose a Component or click an exposed rod or joint. Engineering highlights the selected component; Annotations adds its name and solved endpoint readouts. Clean removes selection decoration for presentation. Mesh thickness, joint bodies, the rack housing and the derived steering-arm solid are illustrative; solved endpoints and wheel orientation remain physical. Historical runs retain their accepted flat support; spatial Road runs use the separately identified normal-distance contact model below.

A native loading or numerical failure publishes no partial result and never changes the backend automatically. Select TypeScript explicitly and run again to use that reference. The older fixed-rack native ABI is preserved separately. All simulation remains local to the browser; no server compute or paid service is required.

Inspect engineering results

Response includes equal-scale world XY trajectory, body velocities/accelerations, attitude, suspension jounce, rack input/effort/work, four tire forces/slips/load/utilization, relative wheel rotation and physical energy accounting. Solver Analysis reports actual stages, steps, timings, real-time factor and physical identities. All values originate from the completed applied result.

Play physics-driven 3D Motion

Open Applied 3D Motion. Body translation/attitude, wheel carriers, steering, jounce, material-relative wheel spin, suspension joints and spring/damper endpoints follow the completed record. The declared world-to-renderer rotation is (x, y, z) → (−y, z, −x), a proper right-handed rotation with unit scale. The executed Road remains stationary.

Use Play/Pause, Reset, time seeking and playback speed. Isometric, Side, Front, Rear and Top views support orbit, pan, zoom, Fit and Reset view; Follow vehicle changes the camera only. Physical Mechanism and Vehicle Context appearances expose the solved mechanisms. Body shell, tire width, link thickness and spring coil symbols are illustrative; they are not dimensional CAD or a deformable tire carcass.

At stored timestamps the exact state is retained. Between samples, cubic Hermite interpolation uses stored generalized coordinates and rates, including unwrapped rotor phase; geometry is solved consistently at displayed jounce/rack. No link endpoints are interpolated independently, and playback runs no force evaluation or numerical integration. Invalid poses are rejected. WebGL failure preserves physical inspection, trajectory and numerical results.

Ownership, cancellation and exports

Cancel or leave the active study to terminate its Worker. Physical edits invalidate preparation and new-run eligibility. Previous results may remain for explicitly labelled historical inspection, with their original vehicle and immutable numerical samples. Late or foreign completions cannot replace the current owner. Project replacement clears advanced session data.

Export full-precision applied CSV and the separately versioned applied evidence JSON. These bind assembly, complements, prepared definition, model, actual backend/solver, source/build, settings, 28-state histories, tires, steering, energy and channel metadata. Save Project preserves workspace-project.v2 and does not silently save advanced complements or buffers.

Stationary Road and actual 14-DOF contact

Road parameters and imported source identity are shared between Ride and Coupled Dynamics. Speed, start position, duration and numerical settings remain model-specific. Each model validates the selected surface independently, so a rough road usable in Ride may reject in Coupled Dynamics. Validation and execution failures appear beside Run; completed evidence remains retained and stale until an eligible run completes. Elevation colour helps reveal small features without changing mesh heights or physical contact coordinates.

In Test, the common Road editor offers Flat, Raised cosine, Sine and browser-local OpenCRG import. Seven-DOF Ride uses its prescribed traversal adapter; 14-DOF Coupled Dynamics advances the actual vehicle over the surface. Temporal Rig histories are separate. Historical zero-flat support remains the default compatibility path. Select Spatial Road contact for its flat limiting case, or select a non-flat Road to use the new model.

Each loaded tire uses the unique closest normal projection onto the analytical or canonical bilinear surface. Compression is effective radius minus normal distance; support acts along the actual normal. Tire forces act in the projected wheel-heading tangent frame, at the computed contact point. Initialization solves heave, roll, pitch and four suspension balances at the initial footprint, then sets rolling speeds. A grade may accelerate the vehicle; preparation does not claim a free parked equilibrium.

This model requires four continuously loaded point supports: elevation within ±0.1 m, slope ≤0.08, curvature ≤0.5/m, cell spacing or wavelength ≥0.02 m and 0.65 m clearance from sampled boundaries and discontinuous lateral edges. Analytical coefficients also require |baseline| + |amplitude| ≤0.1 m. Sampled one-sided gradients must agree under the declared binary64 check; most rough grids are unsupported. No terrain is smoothed or flattened. Compression must remain positive and at most one quarter of effective radius. Mechanical, forward-speed, slip and conditioning guards also apply; unsupported runs fail completely.

The radial point support has no finite-width tire envelope, deformable carcass, separation or recontact. Decorative tire width can intersect a sloped surface away from the authoritative contact marker. Terrain triangles are bounded display approximations at actual scale and never enter physics. New records retain all 122 applicable channels plus 88 contact channels, source/normalized Road hashes, placement, preparation and explicit backend/ABI. CSV and JSON preserve full precision and signed zero. Changing Road or backend invalidates exports. Imported files remain session-owned and require reattachment after project restoration.

The new native ABI 700001 uses fixed 64 MiB memory with bounded allocation and disposal; the historical ABI 680001 and 16 MiB module remain preserved. Every integration stage and contact query runs inside WASM. Initial preparation remains TypeScript. Native failures never select TypeScript automatically. RK4 exposes a separate advancing step of 0.25, 0.5 or 1 ms; the output interval does not redefine that step.

Original synthetic OpenCRG exampleuses a nonconstant straight bilinear surface. It is an independent parser/contact fixture, not measured-road correlation or general ASAM certification. Applied video export remains deferred.

Scientific scope

This is a bounded, unmeasured engineering model. It does not support arbitrary road/OpenCRG maneuvers, reverse/standstill, ABS/ESC or calibrated OEM handling. Qualification checks physical consistency, independent short advancing references, numerical refinement and geometry; it is not measured-vehicle validation and does not independently reproduce every interactive run.

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