The latest generation of electrified drives is produced at the Dingolfing site, the BMW Group competence center for e-drive production. Kuka implemented a fully automated test system here for testing up to eight different drive variants.

Electrified mobility

The Kuka team of experts, based at the Bremen site, invested around two years in the design, construction and finally the successful commissioning of the eDrive test system. "With Kuka's automation expertise, we help our customers to achieve very high volume and variant flexibility," says Stefan Horner, Project Manager at Kuka Assembly & Test in Bremen. "The special feature of this station is the ability to test a very high number of variants with an automation wheel of one hundred percent."

Highest precision - maximum flexibility

The system is divided into two independent test areas. In the first area, the test specimen is tested for its basic function, without adapted output shafts, and for its electrical safety.

The second test area consists of performance tests, all of which are carried out with adapted load machines. Here, the use of a swivel unit and the very rigid, adjustable traversing units for adapting the test specimens with the load machines ensure maximum variant diversity. The swivel unit is used to hold and position the test specimens in the specified test position. High torques can be applied here using a driveline. This highly flexible test system enables a wide range of different types to be tested on one system. "In addition to its mechanical flexibility, the test stand also offers a very wide range of electrical capabilities for testing a wide variety of electric drives," says Johannes Schwanbeck, BMW Planning for Electric Drive Systems. "This means that several eDrive variants can be tested on one system with an extremely high performance and test voltage."

The different output shafts are changed independently using two Kuka KR10 robots. Furthermore, they take over the delivery of the NVH (structure-borne noise) sensors, Kuka for each test specimen, as well as the removal of the radial shaft seal ring caps at a preliminary station. This ensures optimum utilization of the robots.

Own measurement technology software

The customer-specific requirements for the various eDrive variants are validated with the help of Kuka's own measurement technology software, which ensures the recording and validation of the measurement signals during the test runs. "The increasing demands on test depth can be better implemented with a customizable test sequence using Kuka's automation software," says Johannes Schwanbeck.