Robotized temporary micro-factories

Prefab manufacturing using automation, such as multi-family houses or single-family houses, today use production lines with fixed automation in factories with significant initial investment costs. Fully automatic lines are rare. More common is a mix of manual and automated work.

Typically, the automation solution is large to handle the workpiece.The master thesis "Modern Flying Factories in the Construction Industry - A Description of the Concept and Lessons for Further Development" (S. Haukka, M.

Lindqvist 2015) provides a good summary of different types of temporary prefab facilities and what is required for further development.

One of the conclusions is that temporary factories, or also called Modern Flying Factories (MFF), need to find a balance between flexibility and low investment costs in order to achieve efficient production.

Another conclusion is that temporary factories and automation concepts need to be further developed.Since its start in 2018, the Center for Construction Robotics at LTH has invested in small-scale robotics where the robot system is smaller than what is being built, which is not traditionally the case.

The Center has also developed the ACon model, where automation with small-scale robotics and customized building systems is connected with digital design in an unbroken reversible chain.

Within the civil engineering industry, working with unbroken information flows has been an important identified factor for several years.

What is unique about the ACon model is that the uninterrupted flow of information is connected all the way to the robot, which enables faster handling of changes and production control.This project addresses needs in prefabricated wooden house production near the construction site, here called the temporary micro-factory.

The owner is a medium-sized (SME) company that designs, builds and manages modular houses and with this innovation idea wants to see if it is possible to achieve through robotic temporary micro-factories:• Shorter lead time through local in-house production• Retain the climate benefits of ordering from larger suppliers (reduced waste) but increase the degree of ordering from local suppliers (shorter lead time and reduced transport)• More consistent quality regardless of workforce skills (ensuring key skills)Currently, the owner develops concepts and manages the project management of their modular wooden houses, and local construction companies are hired for site construction.There is a need to adapt manufacturing with the order intake to reduce lead time.

Contributing factors to longer lead times in this case are lead times with subcontractors and the necessary management of key competence in local production.

This is to maintain consistent production quality.The hypothesis put forward is that a micro-factory concept with an automation solution enables the maintenance of consistent quality in local production and the use of a local supply chain.

The purpose of the project is to produce data that enables testing of concepts and ideas.The idea consists of a building system intended for the automated production of selected wooden elements in a micro-factory for temporary deployment.

Parts included in the building system are intended to be easier to order with a shorter lead time than previously adapted parts, where adaptation is now carried out locally in a micro-factory as part of the building system.