The FlexibleBodies library, developed by the DLR Institute of Robotics and Mechatronics, offers an object-oriented approach for representing flexible objects within multibody systems. Once the constraints and the applied load system have been defined, it allows to evaluate strains and stresses onto flexible bodies. It also allows users to interface with 1D/3D models from the Mechanics library of the Modelica Standard Library (MSL).

The library provides main models categories:
- pre-defined flexible bodies (beams, plates) whose geometric and mechanical characteristics can be easily set from the graphical interface; their dynamic behavior is described in terms of equations entirely implemented within the Modelica classes.
- generic flexible bodies (ModalBodies), representative of generic shape objects whose mechanical description is based on a finite element model. This model type requires a pre-processing step to be done within an FEA software in order to export both the mesh layout of the body and the modal analysis.