Pro tip: Using dummy resources is a great tool for creating a winning schedule.
For example: We were scheduling surgeries for a hospital. Each surgical procedure required an operating room and, of course, a surgeon. But each surgeon was part of a specialty group like orthopedic, cardio-thoracic ophthalmology, etc. Each of these specialty groups was granted certain times of the week when they had privileges to use the operating rooms. These were called their “block times.” In other words, there was a block time schedule into which we had to book each surgical procedure–orthopedics got Monday afternoons and Thursday mornings, cardiovascular got Wednesdays, and so forth. And to make things more interesting, these block times were enforced when scheduling occurred–unless the procedure was to occur in the next 48 hours.
Here’s how we solved the problem. We created a resource for each specialty, which was its block time. These were place-holders, or “dummy” resources. Each of these dummy resources was made available only at the times granted for that specialty by the hospital. To keep track, we named them “Ortho-Block-Time,” “Cardio-Block-Time,” and so on. We made sufficient quantities available so that several procedures of the same specialty could occur at the same time. Then we required that each surgical procedure require one unit of their appropriate block time (aka: dummy resource). We enforced this constraint unless the start time for the procedure was less than 48 hours away. The result was that all the procedures schedule properly. Hallelujah!
While this scenario is hospital-specific, the same logic of using dummy resources can easily be applied to other industries and scheduling scenarios with the same success.
We have seen situations where organizations have different work hours in different weeks of the month. This can be handled by defining dummy resources such as “Normal-Work-Hours-A,” and “Normal-Work-Hours-B,” etc. Any activity can be scheduled into appropriate work hours by requiring the desired dummy resource. Take schools, gyms, and sports leagues, for example. Some events can be scheduled only on the first Monday of the month or once every three weeks. Using dummy resources fits the bill.
Here’s the caveat: This modeling approach requires that the activities being scheduled be allowed to require any number of specified resources. In the hospital example, each activity required an operating room, a surgeon and the appropriate dummy resource. Of course we could have added equipment, nurses or other resources to the activity definitions. The critical capability is the ability to schedule activities that require multiple resources simultaneously.
Be sure your scheduling tool can do that–then use dummies to make it smart.