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AeroVironment’s Global Observer is an unmanned aircraft with the wingspan of a Boeing 767 but less than 10% of the weight designed to provide communications and sensing for flights lasting up to one week at up to 65,000 feet. With a maximum wing loading of only 3.5 pounds per square feet, the wingtip deflects greater than 22 feet at its design limit load.

MSC Nastran was utilized to develop nonlinear stress, structural dynamic and aeroelastic finite element models. The structural dynamics model was correlated to a ground vibration test, both of which had to accommodate the apparent mass of the air, which is atypical. The ultimate test of the nonlinear stress model was correlation with the static wing load test.

In the past, Sikorsky had to perform expensive bird strike test programs to certify helicopter components. These tests are expensive because they require building prototype components and testing them on a very elaborate rig. For example, the rig used to test the ability of a tail rotor to withstand bird strikes uses a hydrostatic drive …

In my previous blog post I introduced the Adams-EDEM coupling that allows engineers to realistically simulate how bulk materials interact with their systems dynamics. In this post I want to give some insight on the workflow needed to use the coupling.

Fields in Patran are used whenever you need to define variable (non-constant) data. Applications include material properties, element properties, or load variations as a function of time, frequency, or spatial position. Fields are also helpful to map results between dissimilar meshes. Practical uses are briefly described below.

When developing the sub-systems of a vehicle, compromises have to be made among several contrasting objectives. On one hand, one wants to set all sub-systems – such as suspensions – so that they allow efficient and safe handling of the vehicle. On the other hand, comfort cannot be sacrificed too much. Being the support of the vehicle and providing forces necessary to control it, pneumatic tires are one of the most important components. However, it is very challenging to model them due to both their complicated composition and the materials used in their manufacturing process. On top of that, the modeling is done by suppliers and an in depth understanding of the interaction with the vehicle must be attained.

The James Webb Space Telescope is a highly sensitive instrument that is positioned using a precise optical metering support structure. This supporting structure is made from composites to reduce thermal expansion effects while reducing weight. The instrument and structure are subjected to temperatures ranging from ambient during launch to cryogenic temperatures while in orbit. Dynamic and static loads are encountered during launch and in operation respectively.