## Project Planning
### Project Management
The selection process focused on finding a project that maximized the use of digital fabrication while solving a real-world design constraint.
| Criteria | Mannequin Project | Alternative Idea |
| :--- | :--- | :--- |
| **Complexity** | High (Mechanical + Electronic) | Medium |
| **Digital Mfg** | 3D Printing, Laser, CNC, PCB | 3D Printing only |
| **Modelling** | High (Parametric & Kinematic) | Low |
| **Scalability** | High (Modular segments) | Medium |
| **Usability** | Professional Tailoring / Fashion | Hobbyist |
> **Final Decision:** Digital Adjustable Mannequin.
### Scope
The project aims to create a functional prototype focusing on three primary body measurements: **Waist, Bust, and Neck/Shoulders.**
### Roles and Responsibilities
| Role | Lead |
| :--- | :--- |
| **Concept and Design** | Mohammed Azizi |
| **Electronics and Wiring** | Malak Al-Sharqawi |
| **Video and Poster** | Mohammed Azizi |
| **Documentation** | Collaborative |
## Phase 1: Material Selection & Procurement
Following our initial discussions, we drafted a list of all components required to bridge the gap between digital design and physical actuation.
### Bill of Materials (BOM)
| Item | Description | Quantity | Source |
| :--- | :--- | :---: | :--- |
| **NEMA 17** | Stepper Motors | 3 | Local Store |
| **CNC Shield** | V3.0 for Arduino/RP2040 | 1 | Lab Inventory |
| **Lead Screws** | 8mm T8 with Brass Nuts | 3 | Hardware Store |
| **Filament** | PLA (Structure) & PETG (Gears) | 2kg | Lab Stock |
| **Limit Switches**| End-stops for Homing | 3 | Local Store |
## Phase 2: Modelling & Electronics
### 2a: Modelling (Mohammed Azizi)
I created the design models starting with the waist mechanism. This phase included drafting the racks, gears, and the external shell panels.
* **Result:** A full base model and a parametric part list ready for the manufacturing queue.
### 2b: Electronics (Malak Al-Sharqawi)
Investigation into the CNC shield architecture and the logic required to control multiple steppers simultaneously.
* **Result:** Functional CNC shield assembly with confirmed motor rotation and control.
### 2c: Assembly & Manufacturing
We utilized the following digital fabrication tools:
* **Ultimaker:** For high-precision 3D printed mechanical parts.
* **Trotec Laser Cutter:** For structural support plates and housing.
## Phase 3: Prototyping & Calibration
### 3a: 3D Component Testing
I printed various gears and racks to test material durability.
| Part | Material | Walls | Infill | Result |
| :--- | :--- | :---: | :---: | :--- |
| **External Shell** | PLA | 3 | 15% | Success (Lightweight) |
| **Primary Gear** | PETG | 6 | 50% | Success (High Torque) |
| **Rack Gear** | PLA | 4 | 30% | Failed (Brittle teeth) |
### 3b: Preset Coordination
Malak continued testing components, procuring limit switches, and investigating how to correlate motor steps to three functional size presets (S, M, L).
## Phase 4: Testing & Iteration
### Initial Mechanism Test
The waist mechanism assembly was successful upon connection to the CNC shield. However, the upper bust mechanism presented significant friction. The motion was not smooth, and the initial gearbox design for vertical/horizontal motion was too complex.
Analysis of the initial gear-driven bust mechanism showing friction points.
| System Component | Status | Action Required |
| :--- | :---: | :--- |
| **Motor Functionality** | OK | Proceed |
| **Electronic Controls** | OK | Proceed |
| **Mechanical Movement**| ISSUE | Redesign for smoothness |
The Final Pivot: During a final development sprint, I redesigned the mechanism into a Spider Radial Expansion system. This utilizes a multilayered rack and pinion mechanism for much higher reliability.
## Final Results
The transition to the radial expansion mechanism allowed for synchronized, smooth adjustments across all body segments. The prototype successfully responds to digital inputs to match specific anatomical measurements.