A Mixed Model Assembly line is configured to produce several models without changeover. The mixed Model Line, as pioneered by Toyota, is shown at right. A schedule specifies the proportion of each model required for customer demand. In this example, the proportions are 25%, 25% and 50%.

Proper sequencing of products smoothens the demand on upstream suppliers even further. In this example, the sequence is:

RYGY-RYGY-RYGY...

• Red- 1.0 Unit Every 2.0 Hours

• Yellow- 1.0 Unit Every Hour

• Green- 1.0 Unit Every 2.0 Hours

A mixed model line may complicate line operations. However, it streamlines and simplifies upstream operations as well as the inventory, scheduling and transport system that connect the line with these upstream operations. Among the benefits are:

• Upstream Demand Is Steady

• Machines Sized For Customer Demand

• Simplified Scheduling Such As Kanban

• Stable Labor Requirements

• Simpler Transport