LS-Dyna Laminated Glass Failure Model

Damage of glass is characterized in LS-Dyna. PVB material properties is obtained from literature. The damage parameter is implemented in a public CAE model, 2010 Toyota Yaris made by NCAC.

The damage patterns looks ok, but the HIC is quite high. Most probably the number of integration point through thickness, the glass mesh size and also the element formulation is different (the section properties made by NCAC is maintained).

Offset Deformable Barrier Crash Tesh + Occupant + Airbag

I have tried to create a car crash simulation, complete with occupant and airbag. So far far it is running just fine. However, this simulation does not simulate the actual crash test since the step time is increased beyond acceptable level (mass scaling).

Optimization of Airbag

The video uploaded show you one of the simulated iterations. It is optimized using Ls-Opt.

BIW Reinvent

Restarting the development of new concept car. Currently trying to reinvent the whole BIW from scratch. Attached figures are the original BIW for reference (still incomplete).

Offset 40% FEA Comparison

This analysis is made to analyze the passenger safety of our concept lightweight car. Preliminary test in analysis shows that the head injury criteria improved (the value of HIC reduced by 5%) from the default model. However, the chest severity index increase about 3%. 

The video shows the default model at the top and the improved lightweight model at the bottom.

The comparison of energy balance.

Comparison Between the Default Car Model with Weight-Improved Car

I thought I should try to analyze, what if we change the heavy material in our car with the low density material such as aluminium alloys. Would it affect our safety? Yes it would, even though aluminium alloys are lighter, but its strength is lower compared to steel. Furthermore, some process for sheet metal such as hemming and stamping will be a bit difficult. This is because aluminium can easily crack under those process. However, even though it is difficult, it doesn't means that it is impossible. Visit the Aluminium Association on the documentation to explain the details in the manufacturing process for aluminium.

Changing a car to lightweight materials has a lot of advantage. First, it lowers the car fuel consumption. Second, it lowers the car kinetic energy, thus it will make the car safer in a crash event. In this simulation, I attempt to swap 90% of the steel in the model to aluminium. The weight reduction is around 300 kg of kerb weight.

The figure shows the energy balance between the default model and the improved model.

The top car in this video shows the default model while the bottom car is the weight improved car.

The Analysis of Jounce Bumper

This analysis was conducted to find the critical area of failure subjected fluctuated load. The actual part, the CAD data and the FEA analysis is shown in the following figure. Axi-symmetric element is used to speed up the simulation time.