Example 04: Autonomous Vehicle Fleet

Multi-agent cooperative trajectory prediction on complex road networks. 64 vehicles across 4 traffic zones on highways, roundabouts, intersections, and ramps — with isolated, ring, and dense topologies compared.

Source: examples/04_autonomous_vehicle_fleet.py

Results

16-panel figure: Road network geometry, per-zone trajectory plots, speed heatmaps, topology comparison metrics (ADE, FDE, collision rate), attention masks, canvas layout visualization, and training curves.

Animation: 64 vehicles moving through the road network with glowing trails and speed-mapped colors.

Type hierarchy

@dataclass
class Vehicle:
    position: Field = Field(1, 1)
    velocity: Field = Field(1, 1)
    heading: Field = Field(1, 1)
    road_context: Field = Field(1, 2, is_output=False)
    intent: Field = Field(1, 2)
    trajectory: Field = Field(1, 2, loss_weight=4.0)

@dataclass
class TrafficZone:
    signal_state: Field = Field(1, 1, is_output=False)
    congestion: Field = Field(1, 1, loss_weight=2.0)
    vehicles: list  # 16 vehicles per zone

@dataclass
class RoadNetwork:
    global_flow: Field = Field(1, 2)
    zones: list     # 4 zones

Connectivity

Three topology variants compared on the same data:

# Isolated — no inter-vehicle attention
bound_isolated = make_schema(ConnectivityPolicy(
    intra="dense", parent_child="hub_spoke",
    array_element="isolated", temporal="dense"))

# Ring — each vehicle attends to neighbors only
bound_ring = make_schema(ConnectivityPolicy(
    intra="dense", parent_child="hub_spoke",
    array_element="ring", temporal="dense"))

# Dense — full all-pairs attention
bound_dense = make_schema(ConnectivityPolicy(
    intra="dense", parent_child="hub_spoke",
    array_element="dense", temporal="dense"))

Canvas: 25×24 = 600 positions. Isolated: 3,873 connections. Ring: 8,513. Dense: 38,481.

Key metrics

Topology	ADE	FDE	Collision Rate
Isolated	1.32	2.75	23.8%
Ring	2.72	4.82	32.3%
Dense	4.57	7.73	92.0%

Run it

python examples/04_autonomous_vehicle_fleet.py
# Generates: assets/examples/04_fleet.{png,gif,mp4}