Orbital object protection against micrometeorites and orbital garbage may be realized using flexible protective panels made of polymer matrix and ceramic grains. The best protection may be performed using grains of optimal size, specific grains volume content, and appropriate materials. In the view of this, development of parametric FE models with changeable parameters is an actual problem. The adequate description of a panel composite structure is an important modeling item. Composite micro-modeling with the description of each ceramic grain provides the most adequate results. Grains scanning and following image rasterization are used to describe a composite structure instead of abstract grains modeling. The application of voxel modeling and set algebra provides the modeling of an arbitrary composite structure. Plastic kinematic material model is used as a rather simple and adequate to minify computational complexity. Model parameters have been selected using experimental data and applied to describe penetrator impact on composite panel. The research has proved the feasibility of such modeling procedure.