Today’s chapter is about types of scheduling that can be used in manufacturing settings. I think a good place to start would be a definition of a schedule. We define it as an assignment of tasks to resources for a specific date and time. A schedule should be a realistic prediction of future work. A task can be a job, a maintenance task, or a customer visit, etc. A resource can be machine, people, teams of people, et cetera. What you’re usually doing is you’re assigning a job to a machine or to people, to start at a specific time.
There are three types that we’re going to get into. One is kind of a regular run-of-the-mill basic scheduling. Another is schedule of routed tasks. A third one is an idea that we’ve come up with, or we’ve seen in the workplace called queue scheduling.
By Basic Scheduling, we’re referring to the assignment of individual tasks to a resource. The individual tasks are not related to others. A simple example of this could be scheduling of a car repair business. Fixing of a car can be a task and the assignment is the task to a car repair bay for a duration of time. Another example could be appointment scheduling for a doctors office.
The next type of scheduling is Route scheduling. Route scheduling relates to building more complex things that require multiple steps and multiple resources to achieve the end goal. An example could be the assembly of a car. First you need to get the basic frame, next put on tires, next put on sheet metal body, put in passenger chairs, etc. Each step can be scheduled out and a task can only be started when the previous step has been successfully done. Also each step may need to be assigned to a different resource. For example painting of the car, needs to be done in a paint booth. Typical for scheduling of routes, you get this kind of staircase effect for scheduling out of each overall job.
Scheduling of routing gets quite complex because of the potential variations. An example that makes scheduling of routes difficult is say you move, the first step in the route, how is that going to affect the cascaded steps underneath it? How are they going to find open spots and also respect that staircase in terms of, one task needs to be completed before the next one starts.
In MaxScheduler, we actually do not support routing … What happens is that you can support routing if you’re open to scheduling each task individually, you’re not able to make macro changes based on routes. The reason we stay along these lines is that we want to keep MaxScheduler as a simple easy to use scheduling product, to help people who are using spreadsheets or wallboards and want to step up to a computerized tool, but something they can get going quickly.
As soon as you start getting the idea of routes, then people start saying, well, actually I’d like your scheduling software to store all our product information. We want to store the routes in the software and then just be able to schedule each route quickly. That kind of starts slowly turning our software into a much more complex tool, and slowly I think gets us down the path of turning into an MRP product.
The third type scheduling that I want to get into today is queue scheduling. Queue scheduling is the management of line ups of work to resources without regard to date, start times or job durations. A good way to explain this is an analogy to lineups at McDonald’s. If you go to McDonald’s, there maybe be three lineups, you join a line. It is a schedule to a certain degree, you don’t know when you will be served, all you know is that you are the fourth in line.
Queue scheduling makes sense for manufacturers that go through a lot of jobs per day. We have a customer that goes through 150 jobs per day through a small facility. All they really care about is that all the jobs meet their due date. They have a good idea that they have the capacity to do the work. They just want to be organized in their management of line ups of work to resources. Queue scheduling is probably one of the most basic operations management methods that can be used. It allows you to be organized, while minimizing the administrative overhead. With this method, a facility doesn’t need to track setup times, product specific processing rates, estimating job durations, setting job start times, etc.
That’s our overview of the three types of scheduling, and that’s the end of this chapter. Thank you for your time. If you have any comments, questions or interest in MaxScheduler our scheduling software, please reach out to us at MaxScheduler.com. Have a good day.