# Study Report — 01_v1_tpe: Isogrid Mass Minimization

**Study:** isogrid_01_v1_tpe
**Project:** Isogrid Dev Plate (ACS Stack Main Plate)
**Algorithm:** Optuna TPE, seed=42
**Budget:** 200 trials
**Date started:** [TBD]
**Date completed:** [TBD]
**Author:** Antoine + Atomizer

---

## Executive Summary

| Metric | Value |
|--------|-------|
| Status | [TBD — Not started / Running / Complete] |
| Trials completed | [TBD] / 200 |
| Best mass | [TBD] kg |
| Best trial # | [TBD] |
| Convergence trial | [TBD] (when best was first found) |
| Best σ_max | [TBD] MPa |
| Best SF | [TBD] (target ≥ 5.0) |
| Feasibility rate | [TBD] % |
| Total runtime | [TBD] h |
| Avg time/trial | [TBD] s |

---

## Best Design Found

### Parameters

| Variable | Value | Range |
|----------|-------|-------|
| `eta_0` | [TBD] | [0.0, 0.4] |
| `alpha` | [TBD] | [0.3, 2.0] |
| `beta` | [TBD] | [0.0, 1.0] |
| `gamma_stress` | [TBD] | [0.0, 1.5] |
| `R_0` | [TBD] mm | [10, 100] |
| `R_edge` | [TBD] mm | [5, 40] |
| `s_min` | [TBD] mm | [8, 20] |
| `s_max` | [TBD] mm | [25, 60] |

### Results

| Metric | Value |
|--------|-------|
| Mass | [TBD] kg ([TBD] g) |
| Max von Mises | [TBD] MPa |
| Safety factor | [TBD] |
| Feasible | [TBD] |
| Total pockets | [TBD] (sandbox_1 + sandbox_2) |

### Trial folder

```
2_iterations/trial_[TBD]/
├── params.json
├── results.json
├── rib_profile_sandbox_1.json
└── rib_profile_sandbox_2.json
```

---

## Optimization Progress

### Trial Statistics

| Metric | Value |
|--------|-------|
| Total trials | [TBD] |
| Feasible trials | [TBD] ([TBD] %) |
| Failed trials (error) | [TBD] |
| Min objective | [TBD] |
| Median objective | [TBD] |
| Max objective | [TBD] |

### Best History (top 10 improvements)

| Trial # | Mass (kg) | σ_max (MPa) | SF | Feasible |
|---------|-----------|-------------|-----|----------|
| [TBD] | [TBD] | [TBD] | [TBD] | [TBD] |
| ... | ... | ... | ... | ... |

---

## Comparison vs Baseline

| Metric | Baseline (solid) | Best isogrid | Reduction |
|--------|-----------------|--------------|-----------|
| Mass | [TBD] kg | [TBD] kg | [TBD] % |
| Max σ | [TBD] MPa | [TBD] MPa | — |
| SF | [TBD] | [TBD] | — |

> Baseline solid plate mass: TBD (Gap G-02 — run `extract_part_mass_material` on unmodified model).

---

## Runtime Performance

| Metric | Value |
|--------|-------|
| Total wall time | [TBD] h |
| Average per trial | [TBD] s |
| Brain (avg) | [TBD] s |
| NX import (avg) | [TBD] s |
| NX solve (avg) | [TBD] s |
| Extraction (avg) | [TBD] s |
| Fastest trial | [TBD] s |
| Slowest trial | [TBD] s |

---

## Failure Analysis

| Failure type | Count | Notes |
|-------------|-------|-------|
| Brain error | [TBD] | [TBD] |
| NX import failed | [TBD] | [TBD] |
| NX solve failed | [TBD] | [TBD] |
| OP2 missing | [TBD] | [TBD] |
| Extractor error | [TBD] | [TBD] |

---

## Recommendations

> Fill in after campaign completes.

- [ ] If feasibility rate < 80%: increase `s_min` lower bound (too many dense patterns stress-out)
- [ ] If convergence flat after trial 100: consider Campaign 02 with tighter bounds around best region
- [ ] If `gamma_stress` best value > 0.5: stress feedback is helping — keep it in next campaign
- [ ] If best SF >> 5.0: more aggressive lightweighting possible — widen s_max bound

---

## Configuration Reference

**Study name:** `isogrid_01_v1_tpe`
**Constraint:** σ_max ≤ 100.6 MPa (stress only)
**Material:** AL7075-T6, σ_yield = 503 MPa, SF = 5
**DB:** `3_results/study.db`
**Run script:** `run_optimization.py`
**NX version:** DesigncenterNX2512
**NX model:** `1_setup/model/ACS_Stack_Main_Plate_Iso_project_sim2.sim`