How-To

Which job should you schedule first? In what sequence?

Simulation Modeling and Analysis

Dispatching Rules
- Program or set different scheduling heuristics (e.g., First-In-First-Out (FIFO), Earliest Due Date (EDD), Shortest Processing Time (SPT), etc.) in your FlexSim model.
Batch or Sequence Comparison
- Experiment with various sequences in simulation (e.g., schedule high-priority orders first vs. regular jobs first) and observe changes in lead times, WIP, and on-time delivery rates.
Performance Metrics
- Track metrics like average completion time, tardiness, or total throughput under different job-scheduling sequences.

The simulation’s results will highlight which sequence best meets your goals (such as minimizing lateness or balancing throughput).

Lean Thinking Principles

Pull vs. Push
- Lean typically favors pull-based systems where downstream demand “pulls” the jobs. This reduces overproduction and keeps WIP lower.
Takt Time
- Use takt time as a guiding principle. Scheduling should align with the pace of customer demand. The sequence of jobs should support meeting takt time without overburdening resources.
Continuous Flow
- Seek a sequence that allows for steady flow, minimizing waiting times between operations. If certain jobs are “quick wins,” scheduling them earlier might reduce system congestion.

Where should you allocate resources?

Simulation Modeling and Analysis 1. Scenario Testing * Create multiple scenarios in the simulation model. For instance, add or remove a machine or operator at different stations and observe the outcomes. 2. Key Metrics * Track lead time, throughput, and resource utilization for each scenario. * Compare scenarios to see which resource allocation

Building a Process Flow in FlexSim

Creating a clear, structured process flow is the foundation of any effective simulation model. Whether you’re analyzing a manufacturing line, an airport operation, or a service workflow, the goal is the same: define the activities, connect them logically, allocate the right resources, and control the flow of events. This

Given the failure of a resource, how does this this affect your delivery time?

Simulation Modeling and Analysis 1. Downtime Modeling * Build probability distributions or schedules for resource downtime in your FlexSim model (e.g., Mean Time Between Failures (MTBF) and Mean Time To Repair (MTTR)). 2. Scenario Analysis * Run scenarios where a critical machine fails for a certain duration. Observe queue build-up, lead

Where Is the Bottleneck? A Practical Guide to Simulation Modeling and Analysis

Operational problems rarely announce themselves. Instead, queues silently expand, delays accumulate, and throughput declines mysteriously.