CONCLUSIONS

All the goals have been reached: stresses and deformations are under limit values (0.3mm and 138MPa):

The most deformed region of the swingarm is the element on which the pro-link is attached. The shifted point of attachment of the pro-link lead to an asymmetric deformation of the structure, in which the right side is more deformed than the left one. This can lead to an asymmetric dynamic behaviuor of the motorbike.

The maximum stresses are located in small regions of the swingarm, particularly near the pro-link attachment. A solution to decrease further the stresses in those points could be the installation of reinforcing elements, such as ribs, or using larger fillet radii. Also larger thickness of the tubular elements could be used, but this may increase significantly the total weight.

The asymmetry of the structure, due to the prolink attachment, may bring to non-symmetrical behavior of the motorbike, not only in curve, but also in acceleration. This can cause  a bad handling and power transmission. To reduce this effect, we suggest to maintain the same structure and change the thickness of the tubes. This effect is very relevant in turn condition and combined conditions that require very complex  analyses.

Our proposal also took into account the manufacturability the swingarm. The last proposal is made of few tubes (13) and few bendings and weldings are needed. If it was possible to make a more complex structure, tubes may be bended to avoid sharp edges even more.

The most problematic issue was to consider the volumes of all other components. A rough, over-dimensioned design of such components allowed to create a swingarm that guarantees no interferences. In particular, the chain occupies a very big longitudinal space, in which fundamental components of the swingarm have to be placed.

Other analyses can be developed, in order to evaluate the behavior of the motorbike under different conditions, such as turn (with torsional stresses).

We had to work in a very flexible way:

- all Catia models were designed already thinking about possible future modifications;

- volumes of other components (mono, attachments, chain…) were first roughly overdimensioned, because CAD models of those parts were not available at the time;

- when possible, different components of the group worked on different problems simultaneously, always comparing the results and helping each other.

For the first time in our studies we have faced  the problem of designing a mechanical component, working in team, taking into account different kinds of constraints and applying the theoretical knowledge to a practical problem. A big compromise between problem solving, technical knowledge and creativity was needed to identify reasonable solutions.