Example: Activity Split

Split need for an item across multiple suppliers or activities

Activity Splits

There are often cases where a factory sources from multiple suppliers, or even a factory decides to outsource some of it's demand for a product. To model this behavior, the Chaos Solver uses split nodes, or activity splits. In the example here, there are 2 splits:

  1. A split for flour that divides need across 3 farms
  2. A split for bread need at the bakery shop that sources 80% from a regional partner and makes 20% in house

Constrained Behavior

Notice that there is limited inventory for flour at farm_a. In an unconstrained scenario, farm_a would provide 0.2 * 80 = 16 units of flour, but it has just 10 units of flour. The split node handles this scenario by reallocating the additional need to the other suppliers of flour, so instead of farms_b and farm_c providing 32 units of flour, they provide 35. This logic allows all 80 units of flour to be provided to the bakery_shop and mimics how a real supply chain would respond to the constraint.


bom_ids

bom_id location lead_time_days activity_rank activity_split
1 bakery_shop 0.5 1 0.2

bom_inputs

bom_id input_item input_qty
1 flour 4.00
1 water 1.00
1 yeast 0.05

bom_outputs

bom_id output_item output_qty
1 bread 1

demand

location item need_date demand_qty
bakery_shop bread 5/30/2026 100

item_location

item location genesis onhand_qty notes
bread bakery_shop False NaN NaN
flour bakery_shop False NaN NaN
water bakery_shop True NaN assume unlimited supply
yeast vendor_a True NaN assume unlimited supply
bread regional_bakery True NaN NaN
flour farm_a False 10.0 NaN
flour farm_b True NaN NaN
flour farm_c True NaN NaN

lanes

item from_location to_location lead_time_days activity_rank activity_split note
flour farm_a bakery_shop 2 1.0 0.2 NaN
flour farm_b bakery_shop 3 1.0 0.4 NaN
flour farm_c bakery_shop 3 1.0 0.4 NaN
bread regional_bakery bakery_shop 1 1.0 0.8 this is split with a bom id
yeast vendor_a bakery_shop 1 NaN NaN add no rank or split, standard BodEdge should be added

item_location_peggings

item location activity activity_date pegged_qty demand_key
flour farm_b 0_item_genesis 2026-05-26 12:00:00 35.0 0
flour farm_b 7_shipment_from 2026-05-26 12:00:00 35.0 0
flour farm_c 0_item_genesis 2026-05-26 12:00:00 35.0 0
flour farm_c 7_shipment_from 2026-05-26 12:00:00 35.0 0
flour farm_a 5_BOH_usage 2026-05-27 12:00:00 10.0 0
flour farm_a 7_shipment_from 2026-05-27 12:00:00 10.0 0
yeast vendor_a 0_item_genesis 2026-05-28 12:00:00 1.0 0
yeast vendor_a 7_shipment_from 2026-05-28 12:00:00 1.0 0
bread regional_bakery 0_item_genesis 2026-05-29 00:00:00 80.0 0
bread regional_bakery 7_shipment_from 2026-05-29 00:00:00 80.0 0
water bakery_shop 0_item_genesis 2026-05-29 12:00:00 20.0 0
flour bakery_shop 2_shipment_to 2026-05-29 12:00:00 35.0 0
flour bakery_shop 2_shipment_to 2026-05-29 12:00:00 35.0 0
flour bakery_shop 2_shipment_to 2026-05-29 12:00:00 10.0 0
yeast bakery_shop 2_shipment_to 2026-05-29 12:00:00 1.0 0
flour bakery_shop 4_activity_split_output 2026-05-29 12:00:00 80.0 0
flour bakery_shop 6_BOM_input 2026-05-29 12:00:00 80.0 0
water bakery_shop 6_BOM_input 2026-05-29 12:00:00 20.0 0
yeast bakery_shop 6_BOM_input 2026-05-29 12:00:00 1.0 0
bread bakery_shop 2_shipment_to 2026-05-30 00:00:00 80.0 0
bread bakery_shop 3_BOM_output 2026-05-30 00:00:00 20.0 0
bread bakery_shop 4_activity_split_output 2026-05-30 00:00:00 100.0 0

shipments

level from_location to_location item ship_date arrival_date shipment_qty demand_key
2 regional_bakery bakery_shop bread 2026-05-29 00:00:00 2026-05-30 00:00:00 80.0 0
6 vendor_a bakery_shop yeast 2026-05-28 12:00:00 2026-05-29 12:00:00 1.0 0
12 farm_a bakery_shop flour 2026-05-27 12:00:00 2026-05-29 12:00:00 10.0 0
14 farm_b bakery_shop flour 2026-05-26 12:00:00 2026-05-29 12:00:00 35.0 0
16 farm_c bakery_shop flour 2026-05-26 12:00:00 2026-05-29 12:00:00 35.0 0 

Loading Supply Chain Network from Files
Running obo Solver
***Starting to plan for demand key 0***
At bakery_shop on 2026-05-30: Searching inventory for 100 units of bread
At bakery_shop: No inventory for bread
At bakery_shop: Searching rank 1.0 SplitOutputEdge Split-2 to bread-bakery_shop with LT 0.0 days
--At bakery_shop: Searching bread-regional_bakery to Split-2 with LT 1.0 days for split 80.0/100
----At regional_bakery on 2026-05-29: Genesis Node for bread. All 80.0 need satisfied
--At bakery_shop: Found all expected split qty
--At bakery_shop: Searching BOM-1 to Split-2 with LT 0.5 days for split 20.0/100
----At BOM 1 input 1/3: Searching for 80.0 of flour
------At bakery_shop on 2026-05-29: Searching inventory for 80.0 units of flour
------At bakery_shop: No inventory for flour
------At bakery_shop: Searching rank 1.0 SplitOutputEdge Split-1 to flour-bakery_shop with LT 0.0 days
--------At bakery_shop: Searching flour-farm_a to Split-1 with LT 2.0 days for split 16.0/80.0
----------At farm_a on 2026-05-27: Searching inventory for 16.0 units of flour
----------At farm_a: Found 10.0/16.0 inventory for flour
----------At farm_a: No parent edges to search. Returning found supply 10.0
--------At bakery_shop: Found ratio 0.125. Need to replan
--------At bakery_shop: Replanning with new splits: [0.125, 0.4375, 0.4375].
--------At bakery_shop: Searching flour-farm_a to Split-1 with LT 2.0 days for split 10.0/80.0
----------At farm_a on 2026-05-27: Searching inventory for 10.0 units of flour
----------At farm_a: Inventory meets all 10.0 need for flour
--------At bakery_shop: Found all expected split qty
--------At bakery_shop: Searching flour-farm_b to Split-1 with LT 3.0 days for split 35.0/80.0
----------At farm_b on 2026-05-26: Genesis Node for flour. All 35.0 need satisfied
--------At bakery_shop: Found all expected split qty
--------At bakery_shop: Searching flour-farm_c to Split-1 with LT 3.0 days for split 35.0/80.0
----------At farm_c on 2026-05-26: Genesis Node for flour. All 35.0 need satisfied
--------At bakery_shop: Found all expected split qty
--------At bakery_shop: Found all qty for Split-1
------At bakery_shop: Found 80.0/80.0 on edge Split-1 to flour-bakery_shop
------At bakery_shop: Found all supply. Done searching edges of flour-bakery_shop
----At BOM 1 input 1/3: Found all supply for flour
----At BOM 1 input 2/3: Searching for 20.0 of water
------At bakery_shop on 2026-05-29: Genesis Node for water. All 20.0 need satisfied
----At BOM 1 input 2/3: Found all supply for water
----At BOM 1 input 3/3: Searching for 1.0 of yeast
------At bakery_shop on 2026-05-29: Searching inventory for 1.0 units of yeast
------At bakery_shop: No inventory for yeast
------At bakery_shop: Searching BodEdge yeast-vendor_a to yeast-bakery_shop with LT 1.0 days
--------At vendor_a on 2026-05-28: Genesis Node for yeast. All 1.0 need satisfied
------At bakery_shop: Found 1.0/1.0 on edge yeast-vendor_a to yeast-bakery_shop
------At bakery_shop: Found all supply. Done searching edges of yeast-bakery_shop
----At BOM 1 input 3/3: Found all supply for yeast
----At BOM 1: Done searching all inputs
--At bakery_shop: Found all expected split qty
--At bakery_shop: Found all qty for Split-2
At bakery_shop: Found 100/100 on edge Split-2 to bread-bakery_shop
At bakery_shop: Found all supply. Done searching edges of bread-bakery_shop
***Found 100.00% supply for demand key 0***
Solver complete. Writing output

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