One of the fundamental problems in project delivery is that scheduling tools are not able to simulate real-life work scenarios correctly.
In project schedules there are often some activities that require assignment of more than one resource. In some situations activities could be performed only when all resources are available. In other scenarios activities could commence as soon as any resource is available.
In this scenario we have two resources assigned to complete work. Unless both of these resources are available the work can not be done.
We need to move tables. There are two workers required to carry a table. This work can start only when both resources are available.
The activity will not be completed quicker even if a third worker would be available for this task.
In the second scenario, we also have two resources assigned. However, the nature of this activity allows them to work independently one from another. The work can start as soon as one of the resources is available.
We are moving chairs. Only one person is needed to carry a chair. The assigned workers can move the chairs independently one from another. Any available worker could start moving chairs. When (and if) the second resource is available, both resources will work together and complete the work faster.
Similarly to the previous example, the duration of this work is also dependant on the availability of assigned resources. However, a different type of logic needs to be applied to calculate the duration of this activity.
The activity can be completed quicker if a third worker is also available.
Some activities require more complex simulation when “all” and “any” types of logic need to be combined.
Scenario 3 demonstrates that you can actually combine scenarios 1 and 2 when work could be done by any group of resources.
Some projects use shifts. An activity requires two workers and can be started in any shift. If not completed, two workers from another shift would continue the work.
Majority of scheduling tools really struggle to calculate durations of these scenarios correctly.
Spider Project has a special feature, called “Teams“, that allows the simulation of all possible scenarios of resource assignments.
Team is a group of resources working on an activity together.
The team may include individual resources, multi-resources (crews) and skills (resource pools).
See how Teams Assignments work in Spider Project: