Free body diagram

Under the free blades ( or clearing ) of bodies is defined as a process in the structural analysis for the calculation of acting on them forces and moments. The cut-away problem free body diagram called.

A body and a system (for example, rod, shaft, lever, spring ) is thereby released from the virtual environment. In this case, bearing, weights, bollards and other acting on the system body that counteract a force or take a moment, replaced by standardized symbols. Components of the system that do not affect the balance of power are not shown. Furthermore, the forces and moments acting from the environment to the system detected by, for example, force vectors and penciled dimensions and distances.

The body has after this operation no " touch " to the environment. The result is a simplified model of the system on which light but recognize relationships between forces and moments also force profiles in the system or can be read.

The process is given a great importance in the teaching of statics.