User Report ema V5
Ergonomic evaluation in body manufacturing
In the 2nd half of 2012 the project ‘Ergonomic evaluation in body manufacturing’ was conducted at AUDI AG in Neckarsulm in order to prove the performance of ema V5 in practical application.
AUDI is currently planning a new body shop for producing sports-car at the plant in Neckarsulm.
The requirements for the planning with the software emaV5 include the verification of the scope of work for plausibility, accessibility and ergonomics, which could only be partially evaluated with the previous methods. With the use of emaV5 in this project these objectives should be reached in an efficient workflow. As a special characteristic, this body shop primarily consists of manual work, where workers complete value added joining operations using aluminum welding. After the first work sequences were planned in the virtual environment, it became apparent that the technical feasibility and procedural plausibility must be ensured first. For this reason, a static investigation of accessibility for different geometrical and procedural alternatives was completed in the beginning.
Therefore, a methodology was developed that leads to valid conclusions about the feasibility of manual welding operations in a very efficient way. Hereby, the positioning of the worker in the necessary static poses and the resulting postures were the basis for deriving qualitative conclusions about the ergonomic feasibility. Because of the large number of joints, the investigation was focused on preselected cases that were discussed with the responsible Audi department. In the following, various potentially critical poses were identified which would not have been detected with conventional tools within the given time frame. Based on this selection, the ideal posture of the virtual worker was determined taking the restrictions of the welding fixture into account.
First the reachability of the joint was examined making sure that all relevant welding points are in the reach area of the worker considering the restrictions due to anthropometric characteristics and the geometry of the product and the fixtures. This resulted in conclusions about the tool accessibility in a defined pose and whether or not the manufacturing process would ensure the necessary quality. For the joints that are hard to reach, collisions are unavoidable. The identified contact points between the object periphery and the worker are acceptable to a certain degree and can be interpreted as leaning support. Furthermore, the joining location should be visible to the operator to ensure that the proposed process flow is carried out in the required standard conditions.
Ideal operation conditions were defined in standing posture with welding height at hip level, whereas bending, twisting, kneeling, and overhead work should be avoided. This was done by using extra steps or stools. With the use of this methodology and the parametric and iterative application of emaV5 several potential issues were identified. For most of these critical points it was also possible to define easy and quick solutions to ensure the feasibility of the production process. The early intervention in the device and fixture development enabled an optimal ergonomic design for these workstations. In summary, the support from the imk ensured that all results could be delivered before the project deadline, so working with emaV5 set new standards compared to the previous evaluation process.
The combination of methodology and effectiveness have significantly improved the quality of results and are not just benefitting the current planning activities, but also provide the basis for future projects to reach valid insights in an early planning phase.