This project has occupied the majority of my time here at UBC. The project involves the simulation of laminated composite materials subjected to ballistic impact. Some applications that have been examine include the impact of projectiles on Kevlar helmets, or the impact of fragments on vehicle armour. Other potential applications include the foreign object strikes on aerospace vehicles (birds, hail, etc.) as well as low velocity impacts like tool-drops or gangway collisions.

Using a constituitive model that incorporates damage, these events can be simulated within finite element codes. The code that is used at UBC is LS-DYNA, an explicit finite element package used extensively by the automobile, aerospace, and defence industries.

The constituitive model that I have been using was originally developed by a former UBC Composites Group graduate student, Dr. Kevin Williams. Following Dr. Williams' graduation, I extended his ideas and incorporated a number of changes to the implementation and interpretation of his model. The model, called the composites daage model (CODAM) is based on continuum damage mechanics (CDM) and is intended for use with macro-scale high-damage modelling of fibre reinforced composite laminates.

For more information on CODAM, watch this slide show. (Note that some of the animations near the end may take some time to load).

To view the animations separately visit these links:

• 9mm FMJ Impact (1.7 MB)
• 120° Conical Projectile Impact (2.4 MB)
• 37° Conical Projectile Impact (2.3 MB)
• FSP Impact (3.6 MB)

Here are links to papers on this project:

• Ballistics 99 Conference Paper (1999)
• 5th Dyna User's Conference Paper (1998)

As in the previous project, this project uses CODAM to model damage growth in laminated composite materials. However, in this instance, the damage is a crack growing in a compact tension test specimen. The method of introducing damage into the material is different than the ballistic impact event, but the type of material is the same, and the model considers damage in general. So, the CODAM model is as applicable in this case as other loading conditions.

Considerably more has been published on this project, and several links below will take you to more information:

• 33rd International SAMPE Technical Conference (2001)
• ICCM 13 Conference Paper (2001)
• ICCM 12 Conference Paper (1999)

I was heavily in the initial stages of the design of the UBC entry to the Igor Sikorsky Human Powered Helicopter competition, the Thunderbird. My involvement included the structural design and material selection on the selected design. In recent years, however, time demands from other projects has kept me away from this one. You can find details on the status of the project at http://www.mech.ubc.ca/~hph .