Graph-Based Maps¶
How warehouse topology is represented.
Graph Structure¶
A warehouse map is a weighted graph G = (V, E):
- V: Set of nodes (vertices)
- E: Set of edges connecting nodes
- w: Edge weights (lengths)
Why Graphs?¶
Flexibility¶
- Any layout can be represented
- Non-rectangular warehouses
- Multiple floors (separate graphs)
Efficiency¶
- Standard graph algorithms
- Fast pathfinding
- Compact representation
Realism¶
- Actual travel paths
- Accurate distances
- Physical constraints
Map Components¶
Nodes (Vertices)¶
Properties:
- Unique identifier
- Position coordinates
- Type classification
Edges¶
Properties:
- Source and destination nodes
- Physical length
- Directionality
Map Topology¶
Connected Graph¶
All nodes must be reachable:
- No isolated nodes
- No disconnected regions
- Robots can reach any location
Bidirectional vs One-Way¶
Bidirectional (default):
- Robots can travel both directions
- Most flexible
One-way:
- Traffic flow control
- Reduces congestion
- More complex routing
Pathfinding¶
Shortest Path¶
Default routing finds shortest path by distance.
A* Algorithm¶
Uses heuristic for faster long-distance routing:
Where:
- g(n): Actual cost from start
- h(n): Estimated cost to goal (Euclidean distance)
Congestion-Aware¶
Optional weighting by current congestion:
Example Layouts¶
Simple Grid¶
5x5 grid with 3m spacing:
[N0]--[N1]--[N2]--[N3]--[N4]
| | | | |
[N5]--[N6]--[N7]--[N8]--[N9]
| | | | |
...
Zone-Based¶
Best Practices¶
Node Density¶
- More nodes = finer granularity
- Fewer nodes = simpler routing
- Balance accuracy vs. complexity
Edge Lengths¶
- Use actual physical distances
- Consistent units (meters)
- Account for corners/turns
Capacity Planning¶
- Identify bottleneck paths
- Add parallel routes if needed
- Consider traffic flow