PSI - Issue 8

F. Caputo et al. / Procedia Structural Integrity 8 (2018) 297–308 Author name / Structural Integrity Procedia 00 (2017) 000 – 000

11

307

Figure 11. Left elbow flexion.

Table 3. Jeep Renegade central tunnel assembly: numerical vs. experimental results. Numerical results

Experimental results

Section 1 Section 2 Section 3 Section 4

26 44

16 43

0

0

25.5

21

The results in Table 3 show some difference between the two methods, about section 1 (postures) particularly, due to a less realistic way of carrying-out the same activity by the virtual manikin. For Jeep Renegade central tunnel assembly there is a moderate risk in section 2, due to the use of screwdrivers that cause high counter-reaction forces.

4. Conclusions

A preventive performance evaluation of workstations design is a crucial passage to test the product feasibility since the design phase of a new product, giving the opportunity to reduce time and costs and the possibility to change design parameters without risks. Simulating operating tasks in a virtual environment provides a high number of data, useful to test the product feasibility based on ergonomic indexes. The method proposed by this research, starting from a preliminary design of the workplace, allows to validate its goodness evaluating EAWS index in virtual environment, before, and then in real environment. The comparison of the results, obtained by numerical and experimental methods, shows that, in both cases, despite different proportions, the first one provides a higher value of the index than the second. This means that the analysis of the results obtained by virtual simulation is more conservative than the traditional one. This latter aspect would make it suitable for the design phase, with a significant reduction in costs for the implementation phase and an improvement in the working conditions of the operators, who will immediately have available a workstation of which ergonomic efficiency has been previously validated. Furthermore, the difference between the same activity performed in two different plants shows that improving the workstation design when a new plant, in this case Melfi, needs to be builted leads to the creation of more efficient production system and, at the same time, more secure for workers. Finally, the use of wearable devices, for this research a homemade inertial motion capture system, allows a definitive validation of the workstation design reproducing physical activity in laboratory or thanks to immersive reality technologies.