Tasks and processes
A task is a piece of work with a duration that occupies one or more resources. The tasks of a job are described once in a process (a template) and instantiated for each order or unit.
Fields of a process task
Section titled “Fields of a process task”| Field | What it is |
|---|---|
| Name and task type | Task types can inherit properties from another type |
| Resource requirements | Which resources it occupies at once and how many of each |
| Duration | Fixed, different depending on the chosen resource, or a formula |
| Precedences | Which tasks must finish first, with minimum and maximum waits |
| Earliest start | It cannot start before this moment (for example, when a material arrives) |
| Repetitions | How many identical units are made |
| Properties | Specific values: length, number of parts, service type |
Resources and alternatives
Section titled “Resources and alternatives”Each resource requirement can have alternatives. The engine chooses the one that best fits the objectives.
| Form | Example |
|---|---|
| A resource type | Any Welder |
| A specific resource | Booth 1 |
| A condition | Resources whose maximum load ≥ part weight |
| Several resources at once | An overhead crane and two technicians |
The duration can depend on the chosen alternative: the same phase takes 5 hours on one machine and 6 on another.
Precedences and waits
Section titled “Precedences and waits”A precedence says that one task goes after another. It can include:
- Minimum wait: time that must pass between the end of one and the start of the next (curing, drying, cooling).
- Maximum wait: time that must not pass (a material that cannot wait longer than a certain time).
With repetitions, the precedence can be one to one (each cutting unit feeds one welding unit, in a chain) or all to all (assembly waits for all the previous units).
Repetitions and splitting
Section titled “Repetitions and splitting”- Repetitions: a task done k times, for example once for each part in a batch.
- Splitting: a large job divided into k parts that can go to different resources.
Alternative routes
Section titled “Alternative routes”Some processes have mutually exclusive branches: either path A or path B is done, not both. The engine chooses the branch.
Several tasks in one order
Section titled “Several tasks in one order”The tasks of the same order do not overlap with each other unless stated otherwise.