abaqus-optimization

# Tosca CLI Workflow Skill This skill covers **executing** topology optimization via the Tosca CLI. For **authoring** the `.par` file (design responses, objectives, constraints, frozen regions), see the tosca skill. For the **complete end-to-end topology optimization workflow** (geometry through results), see `/abaqus-topology-optimization`. ## When to Use This Skill **Route here when user mentions:** - "run optimization", "tosca optimize", "start tosca" - "check run", "test run", "test1" - "SLURM job", "submit to cluster", "CHPC", "sbatch" - "optimization report", "convergence", "post-processing results" - "smoothing", "STL export", "iso smoothing" - "validation run", "run FEA on optimized design" - "flatten inp", "renumber RP nodes" - Debugging Tosca CLI errors (segfault, license, stale files) **Route elsewhere:** - Writing `.par` file content (DV_TOPO, DRESP, CONSTRAINT, etc.) -> tosca skill - Complete topology optimization workflow -> `/abaqus-topology-optimization` - Building the FEA model (geometry, mesh, BCs, loads) -> module skills - CAE-based optimization API (TopologyTask, ObjectiveFunction) -> valid alternative for Abaqus built-in optimization; see `/abaqus-topology-optimization` for correct usage ## Two Optimization Paths ### Path A: CAE API (Abaqus built-in optimization) The CAE optimization API (`TopologyTask`, `ObjectiveFunction`, `OptimizationProcess`) works correctly when used with the proper tuple format. The key pitfall: `ObjectiveFunction.objectives` must use **4-tuples** `(suppress, designResponse, weight, referenceValue)`. Passing a 5-tuple (e.g., with a trailing empty string) corrupts C++ state and causes segfaults/KeyErrors. See `/abaqus-topology-optimization` for correct CAE API usage patterns. ### Path B: Tosca CLI (primary workflow for this project) For Tosca-specific features or standalone Tosca execution, the hybrid pipeline is used: ``` CAE Python API (noGUI) Tosca CLI -------------------------- --------- 1. Build geometry 2. Mesh 3. Material + section 4. Assembly, step, BCs, loads 5. noPartsInputFile=ON -------> 6. Generate .par file (hand-written) + writeInput() 7. tosca optimize -p file.par -s abaqus 8. Output: ISO_SMOOTHING.stl ``` **Note:** Tosca `.par` files must be hand-written. CAE generates `.par` for its own optimization system, not for standalone Tosca. ## Prerequisites Before running Tosca CLI: 1. A flat `.inp` file (use `noPartsInputFile=ON` before `writeInput()`) 2. A `.par` parameter file referencing the flat `.inp` 3. Full Abaqus license with Tosca module (not Learning Edition) 4. Tosca on PATH (`tosca` command available or `abaqus tosca`) ## Workflow: Running Optimization ### Step 1: Generate Flat .inp File Tosca requires flat `.inp` files without `*Part`/`*Instance`/`*Assembly` hierarchy. Use `noPartsInputFile=ON` before `writeInput()`: ```python mdb.models['Model-1'].setValues(noPartsInputFile=ON) mdb.jobs[job_name].writeInput() ``` This produces a flat `.inp` directly — no manual flattening or RP node renumbering needed. **Legacy approach:** If `noPartsInputFile` is not available, the `.inp` can be flattened manually. See `references/common-patterns.md` Pattern 1 and Pattern 2 for the legacy flattening code. ### Step 2: Check Run (Test Before Optimizing) ```bash ToscaStructure --job JOBNAME --solver abaqus --type test1 ``` This validates the FE model and `.par` file without running a full optimization. Always do this first. ### Step 3: Run Optimization ```bash tosca optimize -j JOBNAME -p PARFILE -s abaqus -scpus N ``` Or equivalently: ```bash ToscaStructure --job JOBNAME --solver abaqus ``` The `.par` file must reference the flattened `.inp` via `FILE = flat.inp` in its `FEM_INPUT` block. Both files must be in the current working directory or use absolute paths. ### Step 4: Monitor Progress - Watch `JOBNAME/TOSCA.OUT` for CRITICAL/ERROR/WARNING messages - Check `optimization_report.csv` for per-cycle objective and constraint values - Check `optimization_status_all.csv` for extended convergence metrics ### Step 5: Generate Report and Smooth Results ```bash # Generate postprocessing report (.vtfx for visualization) ToscaStructure --job JOBNAME --report # Smooth results for CAD export (STL) ToscaStructure --job JOBNAME --smooth ``` ### Step 6: Validation Run (FEA on Optimized Design) Tosca deletes per-cycle ODB files. To visualize stress/displacement on the optimized design, run Abaqus FEA on the last-cycle `.inp` from `SAVE.inp/<N>/`: ```bash cd JOBNAME/SAVE.inp/<last_cycle>/ abaqus job=Optimized input=flat.inp cpus=N interactive ``` The last-cycle `.inp` includes `tosca_distribution.inp` with per-element density values (SIMP penalties), so the FEA runs on the actual optimized topology. ## Key CLI Flags | Flag | Meaning | |------|---------| | `-j JOBNAME` | Job name; Tosca creates a directory with this name | | `-p PARFILE` | Path to the `.par` parameter file | | `-s abaqus` | FE solver to use | | `-scpus N` | Number of CPUs for the FE solver | | `--loglevel DEBUG` | Verbose logging to `TOSCA.OUT` | | `--loglevel_stdout INFO` | Show more detail on stdout | | `--type test1` | Check run (validate without optimizing) | | `--report` | Generate postprocessing data | | `--smooth` | Smooth results for CAD transfer | ## SLURM Integration For HPC clusters, see `references/common-patterns.md` Pattern 3 for a complete SLURM script. Key considerations: - `module load abaqus/2025` (loads both Abaqus and Tosca) - `unset SLURM_GTIDS` (prevents Abaqus MPI issues) - `export I_MPI_HYDRA_TOPOLIB=ipl` (Intel MPI topology) - Set `ABAQUS_NUM_CPUS`, `ABAQUS_MESH_SIZE`, etc. as environment variables - Use `Xvfb` for visualization steps on headless nodes ## Validation Checklist After optimization completes: - [ ] `TOSCA.OUT` shows no CRITICAL or ERROR messages - [ ] `optimization_report.csv` shows objective converging - [ ] Constraints satisfied in final cycle - [ ] STL file produced (if SMOOTH block in `.par`) - [ ] Validation FEA runs on last-cycle `.inp` without errors - [ ] Stress/displacement results are physically reasonable ## Troubleshooting See `references/troubleshooting.md` for detailed error resolution. | Problem | Quick Fix | |---------|-----------| | `tosca: command not found` | Check PATH, try `abaqus tosca` or load module | | Segfault from `submit()` | Check ObjectiveFunction tuple format — must be 4-tuple, not 5-tuple | | KeyError from `writeParAndInputFiles()` | Caused by corrupted C++ state from wrong tuple format; fix ObjectiveFunction 4-tuple | | Stale `.onf`/`.db` files | Delete `JOBNAME/` directory before re-running | | RP node collision | Renumber RP nodes with offset (see Pattern 2) | ## Code Patterns For actual code from the working experiments, see: - [CLI Reference](references/cli-reference.md) - [Common Patterns](references/common-patterns.md) - [Troubleshooting Guide](references/troubleshooting.md)