Search Results

Automotive OEMs are launching multiple products with ever reducing development time, balancing costs, quality and time to market, with clear focus on performance and weight. Platform architecture concepts, modular designs for differentiation etc. are strategies adopted by automotive OEMs towards shorter development cycles. Thus, concept generation phase of the digital product development process is expected to enable generation and evaluation of multiple concept architectures, carry out performance studies and largely focus on optimization, upfront. This Front loading of engineering and call for simultaneous engineering requires support in terms of quick and good CAD modeling with maturity. This paper proposes a process that focuses on generation and evaluation of multiple concepts, besides enabling optimization of concept before the detailed design phase kicks in.

Computer Aided Engineering (CAE) plays an important role in the product development. Now a days major decisions like concept selection and design sign off are taken based on CAE. All the Original Equipment Manufacturers (OEMs) are putting consistent efforts to improve accuracy of the CAE results. In recent years confidence on CAE prediction has been increased mainly because of good correlation of CAE predictions with the test results. Defining proper correlation criteria and using a systematic approach helps significantly in building the overall confidence level for predictions given by CAE simulations. Representation of manufacturing effects on material properties and material failure in the simulation is still a big challenge for achieving a good CAE correlation. This paper describes side impact test vs CAE correlation. The important parameters affecting the CAE correlation were discussed.

In frontal crashes, one of the primary reasons for occupant injuries is hard contact with the vehicle interiors. While restraints like airbags, seat belt pre-tensioners etc. help in preventing direct contact of the upper body region; vehicle interiors play a critical role in controlling the lower body region injuries. Knee injuries can be controlled in various ways as follows: Avoiding contact with the dashboard by use of buckle pre-tensioners etc. Using restraints like knee airbags Optimizing the dashboard profile and stiffness at the contact locations All the above options have their own advantages and limitations. This paper explains the effect of dashboard stiffness tuning for controlling knee injuries in a frontal crash. The development methodology and some validation tools are discussed using a case study.

In vehicular crashes, one of the main causes for occupant injuries is uncontrolled hard contact with the vehicle interiors. Typically in frontal crashes, injuries are mainly caused due to contact with the steering wheel and dashboard. In frontal crashes, upper leg injuries are caused due to forces applied on the knee and lower leg (tibia). This injury is a function of occupant forward movement, dashboard intrusion, dashboard stiffness and hard components behind the dashboard in the knee contact location. While trying to control the above design parameters is possible, provision of knee bolsters to limit the femur and knee injury is a more cost-effective, modular and a relatively simple countermeasure which can be used even for an existing vehicle. Knee bolster is a mechanical energy absorbing member packaged behind the dashboard. This member crushes or folds at a predetermined load due to contact forces from the upper leg, thus controlling the resulting injuries.

There is a continuous effort in enhancing the automobile crashworthiness while also trying to reduce weight. This up-gradation is even more difficult if the vehicle is in production due to additional constraints of production feasibility. Higher strength steels and add-on reinforcements are typical measures taken in such circumstances. Even these modifications require manufacturing setup changes and may lead to increase in product weight. One of the critical issues in automotive safety is to ensure passenger compartment integrity which is sometimes compromised due to section shape failure of a critical member. New concepts using structural foams have been introduced for increased strength. These materials work by avoiding collapse of critical sections and have the potential to provide adequate section strength with minimum mass penalty.