docs: Initial core research and detailed BOM comparison

README.md

@@ -0,0 +1,61 @@
+# CNC Router Project - Core Research & Comparative Analysis
+
+## 1. Executive Summary & Design Goal
+The goal of this project is to research and evaluate the design of a highly portable, cost-effective CNC router for semi-professional and DIY woodworking. Traditonal gantry CNC systems require massive frames, expensive linear rails, ballscrews, and a large dedicated workshop footprint. 
+
+This project pursues a **rail-free, multi-belt/cable-driven suspended or surface-riding kinetic motion system**. 
+The final design should merge the portability and workspace flexibility of **Cubiio X** / **Gordix** with the open-source firmware accessibility and robust DC servo architecture of the **Maslow 4**.
+
+---
+
+## 2. Competitive Landscape: Comparative Analysis
+
+| Feature / Metric | **Gordix** (Muherz) | **Maslow 4/4.1** (Bar Smith) | **Cubiio X** (Muherz) | **Maker Made M2** | **Cubiio** (Laser Only) |
+| :--- | :--- | :--- | :--- | :--- | :--- |
+| **Motion Concept** | Rail-free, surface-riding sled | Flat-rigid-surface riding sled | Rail & Ballscrew compact robot | Frame-suspended sled | Fixed head laser projector |
+| **Kinetic Drive** | **8-Belt** drive system | **4-Belt** drive system | **4 Timing belts** + linear rails | **2 Roller chains** | None (optical galvo) |
+| **Belts / Chains** | 8x High-stress fiberglass timing belts | 4x High-tensile braided Dyneema/UHMWPE line | 4x Gates rubber timing belts | 2x Metal roller chains | None |
+| **Drive Motors** | 8x Sled-mounted motors (calculated) | 4x Sled-mounted 24V DC geared servo motors | 4x Independent stepper/geared motors | 2x Frame-mounted DC geared motors + encoders | Gauges / galvos |
+| **Workspace Capacity** | Up to **4' x 8'** (1.2m x 2.4m) | Up to **4' x 8'** (1.2m x 2.4m) | Up to 4' x 4' (1.2m x 1.2m) | Up to 4' x 8' (1.2m x 2.4m) | Sized by lens focal limit |
+| **Sled Rotation Control** | **Constraint-locked** by 8-belt geometry (Prevents yaw) | **Sled rides material**, yaw resolved mathematically | Standard Cartesian inside frame | Gravity & heavy sled-mass pivot (2-point) | Fixed |
+| **Weight** | ~4.3 kg (very portable) | ~7-8 kg | Moderate, highly integrated | Very heavy (sled + steel chains) | ~1.5 kg |
+| **Spindle / Cutting Head** | 3-in-1: Wood router (Makita body), 10W Laser, Pen | Wood router (Makita RT0701C / Bosch 1617) | Customized miniature spindle plus 10W laser | Standard Wood router (Dewalt/Makita) | laser diode |
+| **Software & Firmware** | Gordix Studio (Proprietary / Closed CAM Web Tool) | **FluidNC (Custom ESP32 branch)**, fully open-source | Proprietary G-code sender / parser (restricted lines) | Makerverse / GRBL | Cubiio App |
+| **Homing & Calibration** | Self-calibrating / anchor reference | **Self-calibrating** (spooling tight to frame anchors) | Manual alignment | Manual/Chain measurement calibration | Optical calibration |
+| **Est. Retail Cost** | ~$1,700 - $3,000 USD | ~$650 USD (Kit form) | ~$1,250 - $1,900 USD | ~$600 USD | ~$400 - $800 USD |
+
+---
+
+## 3. Core Mechanics & Kinematics Study
+
+### 3.1 Understanding the 4-Belt vs 8-Belt Kinematics
+1. **The 4-Belt Limitation (Maslow 4 / Cubiio X):** 
+   - A 4-belt system pulls the sled toward the four corners of the workspace. If the anchor points for the belts are not at the exact mathematical cutting center of the router spindle nozzle, the lateral pulling force induces **yaw rotation (sled rotation)**.
+   - Sled rotation introduces substantial mathematical calculation complexity (since the rotation angle changes dynamically across the workspace) and can degrade dimensional accuracy. 
+   - Additionally, near the corners, a 4-belt system loses tension on one or more belts, causing sag, loss of downforce, or physical slippage.
+2. **The 8-Belt Triumph (Gordix Concept):**
+   - Gordix utilizes an **8-belt architecture** where a twin pair of belts splits to each of the 4 workstation corners. 
+   - By running **two parallel belts to each corner**, the system creates a rigid geometric lock that naturally **constrains yaw (sled rotation)** without requiring software mathematical triangulation of rotational drift.
+   - Sled orientation remains perfectly constant relative to the cutting boundaries, keeping tension balanced across the entire 4'x8' workspace.
+
+### 3.2 The Levitating 3D "Sky Spider" Concept
+During research of the Maslow community archives, an intriguing alternative design was documented: **"Project Sky Spider"** / **"M8 Concept"**.
+- Standard sled designs must **ride directly on top of the woodworking piece**. This introduces challenges with friction, wood chips jamming under the sled, scratching the surface of delicate veneered materials, or getting stuck on pre-carved pockets.
+- The **Sky Spider** concept uses 8 highly tensioned belts (or 4 pair in vertical-opposing 3D diagonals) to **float and hover the entire CNC routing head in 3D space** over the material. 
+- **Mechanical requirements for suspended operation:**
+  - Redesigning spool anchors with ball-joint (like a **CV joint**) to rotate freely in 3D.
+  - Adding a robust, heavy outer boundary frame.
+  - Using longer Z-axis lead screws to drop down into the material from the hovering carriage.
+
+---
+
+## 4. Software & Firmware Strategy
+An open-source, highly customizable software stack is a hard requirement for this DIY/semi-professional project to avoid the limitations of proprietary systems like Gordix Studio or Cubiio.
+
+### 4.1 Recommended Firmware: FluidNC
+- **FluidNC** is the undisputed gold standard for ESP32/ESP32-S3-based kinetic motion controllers. 
+- It is a highly optimized rewrite of **GRBL-ESP32** utilizing a modular, C++ architecture.
+- **Why it fits our project:**
+  - FluidNC supports web page uploading, Wi-Fi Direct (AP Mode), Bluetooth Send, and Telnet on top of standard hardware serial over USB.
+  - It handles multi-axis motor groupings, custom kinematics (such as `wallplotter` or CoreXY), H-bridge drivers directly, and SPI/I2C communication.
+  - Since the **Maslow 4 firmware** is a direct fork of FluidNC, porting the mathematical kinematics for a custom 4-belt or 8-belt kinematics into FluidNC is well-documented and highly achievable.