PhysX Vehicle wheeled vehicles

Wheeled mode uses the chassis wheel array, a simplified powertrain, and a linear tire model with a friction-circle clamp. Start from a template, match anchors to your mesh, then tune grip and handling.

Templates

On PhysX Vehicle Chassis, choose a template and click Apply Template. Applying a template replaces the chassis configuration.

Template	Drive	Typical mass (Rigid Body)	Notes
Sedan	FWD	~1400 kg	Default 4-wheel layout; peak torque ~250 N·m
Off-road / SUV	AWD	~2000 kg	Longer travel suspension, larger tires
Truck	RWD	~8000 kg	Higher torque / brake; 4-wheel simplification of a truck (not multi-axle)

Mass is not written by the template—set it on the PhysX Rigid Body yourself.

Default wheel anchors assume O3DE forward = +Y, up = +Z. Move anchors so rays hit the ground with the intended rest compression when the vehicle sits on its collider clearance.

Assembly checklist

Dynamic Rigid Body + Collider + PhysX Vehicle Chassis (Vehicle Kind = Wheeled).
Apply Sedan / Off-road / Truck template; set mass.
Optional PhysX Vehicle Drive for WASD / gamepad prototyping.
Optional child mesh entities → each wheel’s Wheel Entity Id.
Do not add PhysX Vehicle Track on a wheeled car (Track forces tracked mode).

Car (Entity)
├── PhysX Rigid Body + Collider
├── PhysX Vehicle Chassis (Wheeled)
├── PhysX Vehicle Drive (optional)
├── Body mesh (optional)
└── WheelVisual_FL … RR (optional, linked via Wheel Entity Id)

Drive layouts

`Drive Type`	Driven wheels	Feel
FrontWheel	Front axle (steer wheels typically)	Stable, understeer bias
RearWheel	Rear axle	Easier oversteer
AllWheel	All wheels marked driven	Strong grip / off-road
Tracked	Reserved for tanks	Use Track component instead

Open differential: engine torque is split evenly across driven wheels. Per-wheel Is Driven still matters when combined with drive type.

Handbrake locks the rear for skids. Auto shift uses up / down RPM thresholds when enabled; otherwise call SetGear (reverse < 0, neutral 0, forward > 0). Reverse gear ratio is derived from the first forward ratio.

Steering and chassis helpers

Field	Role
Ackermann ratio	`0` parallel steer … `1` full Ackermann (shared turn center)
Steer rate	Max normalized steer change per second (smooths input)
Max steer angle	Per steering wheel, degrees
Anti-roll stiffness	`0` disables; raise to reduce body roll
Center of mass offset	Local CoM tweak; lower Z resists rollover
Forward axis	Default `PositiveY`

Suspension and tires (practical)

Area	Fields that matter first
Reach ground	`Rest length`, `Max travel`, tire `Radius`, wheel `Local anchor`
Ride height feel	`Auto stiffness` + `Target rest ratio`, or manual `Stiffness`
Bounce	Raise `Damping ratio`; lower stiffness / revisit target rest ratio
Launch traction	Tire `Friction`, `Long stiffness`, drive `Peak torque`
Cornering	Tire `Lat stiffness`, front/rear bias, CoM Y, Ackermann

Use Magic Formula is reserved and unused—keep it off. Tire width mainly affects visuals / future sweep use; the shipped contact is ray-based.

Full field tables: Components.

Tuning tips

Symptom	Try
Understeer	Raise front tire lateral stiffness; move CoM forward
Oversteer	Raise rear lateral stiffness; reduce rear brake bias; reduce rear drive share
Excessive roll	Raise anti-roll stiffness; lower CoM
Wheelspin on launch	Lower peak torque or raise tire friction
Bounce	Raise damping ratio; lower stiffness (or revisit auto-stiffness target rest ratio)
Tips over easily	Lower CoM Z; correct rigid-body mass; add anti-roll
Visual wheels frozen	Assign Wheel Entity Id on each wheel config

Visual sync

After each sub-step, when Wheel Entity Id is set, the solver updates that entity’s transform for suspension compression, steer, and spin. Body meshes are authored separately and are not auto-driven.

Next steps

Tracked vehicles — tanks and differential steering.
Components — complete property tables.
Debugging — suspension rays and force draw.