Motivation and possible applications

Previously published methods for evaluating the energy efficiency of industrial robots bear little relation to real-life applications and therefore offer little added value when selecting suitable systems. The Automation Initiative of German Automobile Manufacturers (AutomatisierungsInitiative Deutscher Automobilhersteller AIDA), as a user of industrial robots, and the Fraunhofer IWU pooled their efforts at the time to develop an energy evaluation system for 6-axis industrial robots that has a maximum connection to real applications and thus offers considerable added value for users when selecting systems for automotive body construction. In addition, the "Energy certificate for industrial robots in car body manufactoring" enables the identification of energy benefits and optimization potentials of individual manufacturers and models.

In a first step, archives of over 1500 robots used in series production by AIDA partners were evaluated using a cluster analysis to identify typical movement parameters. The subdivision into six payload classes was already taken into account here.

Based on the data obtained in this way, payload-specific reference paths were created that match the characteristics of real applications in automotive body construction. In order to create conditions that are as close to reality as possible for the robot's payload, comparative loads were defined that simulate a near-series load on the robot. In order to further increase the validity of the certificate, two additional path variants were developed, with which it is possible to identify optimization potential with regard to performance and energy savings.

The first validation measurements followed in the period from 2014 to 2015, in which exemplary robot models from various manufacturers were measured and the data obtained was evaluated. Following an adjustment of the reference paths and another exemplary measurement, the procedural instructions for self-assessment were published and made available at the  "Fachkonferenz Automobilindustrie" on October 27, 2015, in Augsburg.

As of 2021, the certificate has been slightly revised and translated into English. In the current version (1.2.2) of the process instruction and the associated certificate, the prefix "AIDA" has been dropped. It is now called "Energy certificate for industrial robots in car body manufacturing". Downward compatibility has been ensured so that all certificates already issued remain valid.

The "Energy certificate for industrial robots in car body manufacturing" refers to classic 6-axis articulated robots with a payload of 5 kg or more. The result data sheets with the individual consumption values are specifically geared towards applications in automotive body construction. Data can also be generated for different systems and other areas of application if they are similar in terms of payload and working space, although this may limit the usability of the results.