Project goals, constraints, and philosophy
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Goals
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- Fixed CNC milling machine for aluminum and steel
- Target machining accuracy and repeatability: ≤ 10 µm
- Apartment-compatible operation
- Low airborne noise emission
- Low structure-borne vibration
- High observability of machine state
- Prefer graceful degradation (e.g. feed reduction) over part scrap

Constraints
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- Residential building floor load limit: approx. 150-200 kg/m²
- No heavy concrete or mineral-cast bed
- Controlled total machine mass
- No reliance on software for safety-critical functions
- Noise-sensitive environment
- Downtime acceptable; accuracy prioritized over uptime

Design philosophy
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- Accuracy and repeatability over brute stiffness
- Geometry and load paths over added mass
- Observability over assumption
- Time-scale separation:

  - fast dynamics (vibration, chatter)
  - slow dynamics (deflection, compliance)
  - supervisory decisions (feed and spindle adaptation)
- Fail-safe by construction
- KISS: complexity only where it provides measurable benefit

Explicit non-goals (current phase)
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- Custom servo drives or inverters
- Glass scale feedback
- Active vibration cancellation
- Fully temperature-controlled machine enclosure
- Predictive health monitoring

Documentation scope
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Included:

- Design intent
- Architectural decisions
- Subsystem placement and purpose
- Boundaries between mechanical, electrical, control, and safety layers

Excluded:

- CAD geometry
- Manufacturing drawings
- Assembly procedures
- Firmware and software implementation details