More data (optional)

[pciavald]

Part of what I'm trying to achieve is to be able to send a manufacturing job to a printer in a fleet of printers that has the right material currently loaded for the job.

In order to achieve this, I need to know as much as possible of the mechanical properties of the currently loaded material, given the fact that there are thousands of commercial names for materials and it will be near-impossible, if even desirable, to classify them in a centralized reference database.

My proposition is not to change the required fields, but add many more optional fields. Using a serialization format to store the data should allow still using 1K NFC chips, but if at some point optional data become too powerful, 2K/4K support should be possible while still supporting 1K for required and some optional data.

In this proposition I've also included a section to track the usage of the spool dynamically, and an abrasiveness level that will be discussed in another issue. This is only an initial draft, but it could look something like this:

filament_data = {
  # meta
  'tag_version':           '2',                         # required

  # product
  'manufacturer':          'Francofil',                 # required
  'name':                  'Blue PLA Filament A 110',   # required
  'sku':                   'PLA-110',
  'color_name':            'Blue A 110 Metalized',      # required
  'color_hex':             0x0000FF,
  'manufacturing_method':  'fused_filament_fabrication',
  'certifications':        'rohs,ue:10/2011,reach,fda',
  'additional_data':       None,

  # characteristics
  'diameter_nominal':        1750,                        # required
  'diameter_tolerance':      20,
  'weight_nominal':          1000,                        # required
  'min_extrusion_diameter':  10, # 0.10mm

  # manufacturing data
  'batch':                 '2021-01-01-1234',
  'id':                    '3abe4ae4',
  'manufacture_time':      1612147, # unix timestamp
  'manufacture_location':  '4C5P+JR', # open location code
  'weight_measured':       1003,
  'length_measured':       336,
  'standard_deviation':    3677, # x/1000 um
  'ovality':               180, # x/100 %

  # properties
  'type':                    'polylactic_acid',           # required
  'additional_components':   'thermoplastic_polyurethane:3',
  'properties':              'food_contact_materials,biodegradation',
  'abrasiveness':            1,
  'density':                 1240,                        # required
  'shore':                   75,
  'water_absorption':        5,    # x/10 %
  'surface_resistance':      6,    # 10^x ohm
  'tensile_modulus':         2612, # MPa
  'tensile_stress_yield':    53,   # MPa
  'tensile_stress_break':    51,   # MPa
  'elongation_yield':        21,   # x/10 %
  'elongation_break':        25,   # x/10 %
  'flexural_strength':       100,  # MPa
  'flexural_modulus':        4960, # MPa
  'compressive_strength':    60,   # MPa
  'compressive_modulus':     5000, # MPa
  'compressive_break':       60,   # x/10 %
  'charpy_impact_strength':  26,   # kJ/m^2
  'melt_flow_rate':          720,  # g/10min
  'glass_transition':        575,  # x/10 °C
  'melting_point':           1390, # x/10 °C

  # spool
  'spool_diameter_core':   52,
  'spool_diameter_flange': 200,
  'spool_width':           55,
  'spool_empty_weight':    246,

  # print settings
  'extrusion_temp_min':    190,                         # required
  'extrusion_temp_max':    230,
  'bed_temp_min':          40,                          # required
  'bed_temp_max':          60,

  # properties
  'transmission_distance': 2540,
  'max_dry_temp':          55,
  'humidity_storage':      25,
  'humidity_print':        20,
  'temperature_print':     45,

  # usage
  'remaining_weight':      -1, # grams
  'seen_first':            -1, # unix timestamp
  'seen_last':             -1, # unix timestamp
  'max_humidity':          -1,
  'max_temperature':       -1,
  'computed_density':      -1,
}