Project Management Issues? Your Scheduling May Be the Problem

BY: ROGER TOMLINSON

Completing a project on time and on budget is not an easy task to accomplish. Although there are many variables involved in this process, one way to ensure breezy project completion is to improve your project scheduling. How you choose to schedule your project plays a central role in predicting both the time and cost that will be involved in a project.

A number of techniques for approaching project scheduling have been developed to assist in planning, managing and controlling projects. Read on for two examples of proven methods that can help you better schedule and manage your next project.

Critical Path Method
One useful approach to managing your project schedule is the Critical Path Method (CPM), which maps out the activities within your projects, along with their respective durations, to help you understand how long your project will take. At the beginning of this process, a graph is created which gathers each activity that must be completed for the project, along with estimated duration for each and the order in which they must be completed. The graph will look similar to this:

Once your activities are laid out in this way, a diagram can be created which lays out all the activities involved. This includes the essential steps that must be completed, in order, before a project can be completed. For example, your diagram might look like this:

After each activity is put on the map, you can more easily see the paths involved in your project process. A path can be defined as a series of connected activities from the start to the end of the project. For example, the succession between numbers 1, 4, 8, 13, and 14 (End) is one path included in the map above. This will help with the next step of the CPM, where you create another graph which draws out the paths in order and includes the total duration for each. In this step you will discover the critical path. This will be the longest of all the durations in your project paths, which tells you the earliest possible day that your project can be finished. This graph will look like this:
 

In completing this process, you can better visualize how long each step of your project will take and will be able to predict when your project should be finished.

Program Evaluation and Review Technique
Another technique for project scheduling, commonly used in conjunction with the CPM, is the Program Evaluation and Review Technique (PERT). This tool can be used to construct a schedule when you are not sure if you will have the resources necessary to complete a task, or if you are unsure of how long it will take to complete a certain task.

Due to the uncertainty involved, this technique requires duration estimates for each individual activity:

• Optimistic time estimate (To): This is the shortest possible time in which the activity can be completed, and assumes that everything must occur perfectly.
• Realistic time estimate (Tm): This is the most likely time in which the activity can be completed under normal circumstances.
• Pessimistic time estimate (Tp): This is the longest possible time the activity might need, assuming a worst-case scenario.
• Expected time estimate (Te): This is the best estimate of time required to complete an activity, acknowledging that things do not always proceed as expected.

These numbers can be found by using the following equation:
 

When using this method, it can be helpful to use the same graphs and maps as included in the CPM. To demonstrate, your initial graph of activities may look like this:
 

Next, your diagram of paths and durations would look like this:

Once this is created, your last graph can be drawn out, which includes each path involved in the project and its estimated duration. This also is where you discover your critical path, or estimated time of project completion. For this example, it would look like this:

MEET OUR EXPERT

Roger Tomlinson, Lean Program Manager
Roger has been a Program Manager in The Center’s Lean Business Solutions program for 18 years. He has trained and mentored hundreds of Michigan manufacturers in the entire portfolio of Lean strategies and methods (e.g., Kaizen events, Standardized Work, 5S/Workplace Organization, Value Stream Mapping, Total Productive Maintenance, Culture Change, Team Building, operations management and process re-engineering). In addition to his training and consulting work, Roger has over 20 years of experience in manufacturing management.



Since 1991, the Michigan Manufacturing Technology Center has assisted Michigan’s small and medium-sized businesses to successfully compete and grow. Through personalized services designed to meet the needs of clients, we develop more effective business leaders, drive product and process innovation, promote company-wide operational excellence and foster creative strategies for business growth and greater profitability. Find us at www.the-center.org.