Ambush logic

Vehicles traveling in the theater of operation are at risk of being ambushed by the enemy.  When an ambush occurs, the convoy will either fight off the attackers and incur a small delay, or sustain damage and incur a larger delay.

For modeling purposes, assume that when an ambush occurs, an asset will either be destroyed or unharmed. If destroyed, all the shipments on the destroyed asset will also be destroyed.

Ambush logic is as follows:

• Determine if a convoy was ambushed. This is based on a percentage as defined in the Chance for Ambush column in the Transportation Policies table. For example, when traveling from site A to site B, the convoy will be ambushed 25% of the time.
• If the convoy is ambushed, determine how many vehicles are destroyed. This is determined based on the value in the Ambush Damage column in the Transportation Policies table.
• Ambush logic sets a targeting factor for each vehicle. Every vehicle has an equal chance of being targeted, so ambush logic assigns a random targeting factor to each vehicle. This factor is the percent of time that, when a convoy is ambushed, that asset is considered for destruction.
• Determine the damage factor for each vehicle. This is done by multiplying the targeting factor as described above by the value in the Vulnerability Factor column in the Transportation Assets table. The vulnerability factor is the percent of time that when that asset is targeted, it is destroyed.
• Destroy the vehicles. The correct number of vehicles is destroyed. The vehicles with the highest damage factor are destroyed.
• If a vehicle is destroyed, Simulation will use the Reorder When Destroyed column in the Transportation Policies table to determine if a replacement order is required. When this field is ”Yes”, Simulation places an order that has the same characteristics (due date, qty, product type, etc.) of the destroyed shipment.  When this field is ”No” nothing is done.
• Finally, Simulation determines the delay for the surviving members of the convoy. This is done by multiplying the number of destroyed vehicles by the Delay Factor as defined in the Transportation Policies table. The delay factor can either be a constant number (such as 2 hours per destroyed vehicle) or a distribution.  

You must define a mode with the asset and include this mode on the Transportation Policy. Fields to support ambush logic in the Transportation Policies table are:

The Transportation Assets table includes a field in support of ambush logic:

Ambush logic output

There are 2 output text files that provide information about ambush logic. These files are written to the <ModelName>_NetSimData folder and are not read into the user interface. You enable generation of these files in Simulation options on the Detailed Output tab.

AMBUSH_REPORT.TXT – Fields in this report are:

• Scenario ID
• Scenario Step Number
• Repetition Number
• Source Site
• Destination Site
• Asset Name (the convoy)
• Asset Unit Number
• Shipment ID (for the convoy)
• Ambush Start Time
• Ambush End Time
• Ambush Distance (distance from origin where ambush occurred)
• Total Vehicle Count (the total number of vehicles in the convoy)
• Destroyed Vehicle Count (the number of vehicles destroyed)

DESTROYED_CONSIGNMENTS.TXT – Fields in this report are:

• Scenario ID
• Scenario Step Number
• Repetition Number
• Source Site
• Destination Site
• Asset Name (the convoy)
• Shipment ID (for the convoy)
• Asset Name (the vehicle)
• Shipment ID (for the vehicle's contents)
• Ambush Start Time
• Ambush End Time
• Ambush Distance (distance from origin where ambush occurred)
• Product Name
• Quantity Shipped
• Transportation Cost
• Transportation CO2
• Weight
• Volume
• Duty Cost
• Order Number

Ambush logic example

In this example, there will be an ambush 100% of the time that a convoy moves from a depot to a checkpoint and 40% (2 vehicles of the 5 convoy vehicles) will be destroyed. When the ambush occurs, there will be a 30 minute delay until the surviving assets resume the journey.

Transportation Assets

Two assets – a vehicle and a convoy – are required. An ammo weight of 1 is required to ship on Truck1. The convoy requires at least 5 and no more than 6 vehicles.

Modes and Transportation Policies

Mode 03 describes how the convoy moves from the depot to the checkpoint. In this record, the Chance for Ambush, Ambush Delay, and Ambush Damage are set: