Use this sheet to define pickup-and-delivery relationships between tasks. Each row represents a linked pair of tasks that must be performed together.

When modeling pickup and delivery tasks, demand values must reflect how vehicle load changes.

• A positive demand increases the vehicle’s load (for example, loading 5 pallets onto the truck).
• A negative demand decreases the vehicle’s load (for example, unloading 5 pallets from the truck).

For example, you may have these two tasks:

• Task 1 is a pickup at Site A with a demand of +5 pallets.
• Task 2 is a delivery at Site B with a demand of -5 pallets.

If these tasks represent the movement of the same physical goods, they must be linked in this sheet.

When tasks are paired:

• The pickup task must be completed before the delivery task.

• Both tasks must be assigned to the same vehicle.

• If tasks are optional (via Prize values), they are treated as a single unit — either both are performed or both are skipped. And both tasks must have the same prize value.

Pickup Task ID

Specifies the task that represents the pickup. The pickup task will be scheduled before its corresponding delivery task on the same route.

This field must match a Task ID defined in the Tasks sheet exactly.

Delivery Task ID

Specifies the task that represents the delivery. The delivery task will be scheduled after its corresponding pickup task on the same vehicle route.

This field must match a Task ID defined in the Tasks sheet exactly.

Rules and Structure

• Both Pickup Task ID and Delivery Task ID must exist in the Tasks sheet.

• A pickup must occur before its paired delivery.

• Both tasks in a pair will always be assigned to the same vehicle.

• If Prize values are used, both tasks in a pair must have the same Prize value.

• A task should not appear in more than one pair unless explicitly modeling chained relationships.