Versions of SSMTool:
Contents
SSMTool 1.0
The first public version of SSMTool was provided by Ponsioen and Haller and allows for the computation of
- backbone curves from 2D SSMs
- forced response curves from 2D SSMs
- displaying of SSMs and the dynamics on them
Its algorithm relies on an initial modal transformation of the full dynamical system.
SSMTool 2.0
This updated pre-release version, SSMTool 2, due to Jain, Thurnher, Li and Haller computes the invariant SSMs directly from physical coordinates, thereby allowing for the treatment of much larger dynamical systems. It features the same methods as the first version and includes the computation of FRCs for the following Finite-Element Models (FEM):
- von Karman Straight Beam in 2D
- von Karman shell-based shallow curved panel in 3D
- NACA airfoil based aircraft wing model (>200k DOFs)
SSMTool 2.1
In this official release of SSMTool 2.1, further examples are added to the library. Changes to improve the computational efficiency are employed as well.
SSMTool 2.2
This update to SSMTool2.2 allows for the treatment of systems with internal resonances by computing SSMs of higher dimensions. The changes include
- Addition of continuation of invariant tori for the reduced dynamics
- Examples featuring 1:1, 1:2, 1:1:1 and 1:3 internal resonances and exhibiting invariant tori
- parallel computation of the leading order approximation to the SSM
SSMTool 2.3
In this version, SSMTool2.3 systems featuring algebraic constraints (DAEs) are included.
- Extension of methodology to constrained mechanical systems, including several examples
- Example of a fluid-structure interaction, with flow-induced gyroscopic and follower forces
SSMTool 2.4
In SSMTool2.4 the treatment of systems with direct parametric excitation is enabled by computing higher order approximations to the non-autonomous manifold. The changes include
- computation of high-order approximations to the non-autonomous SSMs
- automatic extraction of Stability Diagrams directly from the ROM, including examples
- analytic extraction of the FRCs for systems with parametric and direct excitation, including examples.
- Efficient parallel computation for the analytic routine for extracting FRCs, also for high order non-autonomous approximations to the SSM
SSMTool 2.5
In SSMTool2.5 the support for the extraction of forced response surface and optimization of periodic orbits is provided. The changes include
- Computation of forced response surface (FRS) via SSM-based model reduction
- Extraction of ridges and trenches of FRS without computing the surface
- Explicit adjoints and gradients for the optimization of periodic orbits via SSM-based ROMs
Publications
A summary of the publications on SSM-Theory which are available thus far can be found here.