Simple Santa Manufacturing Shop (Part 3— Assembly Task Planning)

Elements of the digital twin in manufacturing by example — planning the assembly tasks

In the previous article we have looked into how Santa has planned the assembly processes for his base products — but how does he distribute the different operations on the elves ?

different assembly task organisation for different elve types

There are different type of elves — some of them like complex tasks and aim to build the complete product with all variants, they are willing and able to do training and build up the skills required to master all process steps.
Others prefer simple repetetive tasks which they can do almost automatically all day after short training which enables them to think about their next trip to south pole while working.

So in order to take in account both types of elves Santa has designed two types of workspaces - a single workcell in which one elve can create all product variants by himself and an assembly line with different stations for one or two elves performing different parts of the assembly process.

simple tasks for different elves or a single complex tasks for one elve

The assembly process is either performed by one elve in a single workcell or split up into several tasks performed by different elves on different stations of the assembly line.

Digital Twin Elements

Assembly Task, Station, Working Area, Workplace

In order to be able to distribute the assembly work on different workstations we split the assembly process into several assembly tasks which group assembly operations into units of work.

Each operation has certain requirements which have to be provided by the production context, for example a tool has to be present, a fixture has to be in the correct position, the worker has to have a certain qualification, material has to be provided.

Therefore each assembly task imposes different requirements on the production context depending on the assembly operations it references.

each operation in an assembly task imposes requirements on the workstation context

We can see the workplace as the corresponding element for the assembly task requirements in the production context. The production scheduler uses these workplace definitions to assign concrete workers who meet the capability requirements to the actual workplace.

The working area builds the spatial context for the workplace whereas the station builds the topological context for the workplace.

The inclined reader can dig deeper into how to describe capabilities of industrie 4.0 components in this paper of the german “Plattform Industrie 4.0” consortium.

So now that we have split the assembly process into assembly tasks we are aware of the requirements that come with them for the worplaces and their workstations — how does the actual workstation layout look like and how do we provide the materials needed ?

See in the next part …