In the SMErobotics project the Institute of Robotics and Mechatronics of the German Aerospace Center (DLR), the Lehrstuhl für Robotik und Mensch-Technik-Interaktion of TU Chemnitz and the robot manufacturer KUKA develop efficient robotic automation solutions especially for small and medium quantities. Their main focus is the easy and flexible assembly of individual units.
While many technical products are built from a limited set of basic components, present-day assembly solutions are difficult to adapt to new variants and customer specific requirements. Furthermore their installation is complex and often requires expert knowledge about automation.
In the future the combination of modern planning algorithms for robotic systems, a knowledge database and user software will allow a variable, configurable (complete or partial) automation of industrial work cells with minimal programming and integration effort.
The knowledge database contains CAD models of all basic components, the properties of the robot and preconfigured robot actions. The latter ones can - due to their symbolic parametrization – easily be adapted to various assembly scenarios and therefore be reused in different applications.
An automated assembly planner derives the assembly steps from the CAD data and creates a robot program which takes into account both the robot kinematic and the layout of the fixation aids .
Using a simulation tool the user can in advance test the assembly procedure and optimize the layout of the work cell, e.g. by adapting the positions of the robot base or the fixation aids.
Thanks to the robust implementation and the use of the sensitive control capabilities of the light-weight robot KUKA LBR iiwa small deviations between simulation and reality of the work cell (e.g. imprecise position data of workpieces or fixations) can be compensated without elaborate calibration procedures.
At the AUTOMATICA 2014 fair in Munich a technology demonstrator was presented, where a KUKA LBR iiwa assembled profiles and connectors from a building kit system for industrial use: The visitors created a master model, which the robot reproduced and screwed together. To do so, the master model was captured by a video camera and transferred to a CAD model using the knowledge database. Based on this CAD model the automatic assembly planner calculated the assembly plan and generated the robot program .
 Ulrike Thomas, Theodoros Stouraitis And Maximo A. Roa, “Flexible Assembly Through Integrated Assembly Sequence Planning and Grasp Planning”, IEEE International Conference on Automation Science and Engineering - CASE 2015, pp. 586-592, Gothermburg, Sweden, 24-28 August 2015. doi: 10.1109/CoASE.2015.7294142. elib