"Bringing technology to people" - this was the title of a research project funded by the German Federal Ministry of Education and Research launched in 2014 to develop a craftsman's power system with adaptive human-machine interaction.

This "third arm" for support during physically strenuous work should fulfill three main functions as an overall system: Firstly, force support for load reduction and reduction of fatigue; secondly, the fusion of various measured variables for position detection and projection of relevant information into the workspace (augmentation); thirdly, intuitive use and adaptive adjustment to different users and working environments.

Particular attention was paid to the augmentation function, based on augmented reality systems (AR). As a key component of the "third arm", this function provides the worker with information about the work to be carried out via overlays.

Würth Elektronik CBT was the coordinator of the research project

The three-year research project has now been successfully completed. The project coordinator was the company Würth Elektronik Circuit Board Technology (CBT), the partners were the Karlsruhe Institute of Technology (KIT), the Mechatronics Center Hanover (MZH), Robert Bosch GmbH in Renningen and other participants from industry and trade.

"Würth Elektronik CBT acted as the overall project coordinator and technology provider responsible for the technical implementation of the sensor technology, the development and production of electronics and the design and provision of demonstrators," explains Dr. Jan Kostelnik, Head of Research and Development at Würth Elektronik CBT.

In the course of the project, various options were initially investigated for implementing PCB-based strain gauges with flexible carbon pastes on flexible substrates. A multi-axis force sensor built using this technology was to measure the forces acting on the exoskeleton with each movement of the craftsman. "This is done by relating the bending of a flexible polyimide printed circuit board to the forces acting on it," explains Kostelnik.

Further work included the development of a complex sensor and actuator concept, i.e. the design of a suitable drive for the expected influencing variables, such as the weight forces generated by heavy machines, which previously had to be borne by the craftsman. The sensor and actuator concept was defined in collaboration with the project partner MZH.