[
  {
    "type": "pcb_board",
    "pcb_board_id": "pcb_board_1",
    "width": 20,
    "height": 15,
    "thickness": 1.6,
    "center": { "x": 10, "y": 7.5 },
    "outline": [
      { "x": 0, "y": 0 },
      { "x": 20, "y": 0 },
      { "x": 20, "y": 15 },
      { "x": 0, "y": 15 }
    ]
  },
  {
    "type": "pcb_hole",
    "pcb_hole_id": "pcb_hole_1",
    "hole_shape": "circle",
    "hole_diameter": 1.0,
    "x": 5,
    "y": 5
  },
  {
    "type": "pcb_hole",
    "pcb_hole_id": "pcb_hole_2",
    "hole_shape": "circle",
    "hole_diameter": 1.5,
    "x": 15,
    "y": 5
  },
  {
    "type": "pcb_hole",
    "pcb_hole_id": "pcb_hole_3",
    "hole_shape": "circle",
    "hole_diameter": 2.0,
    "x": 10,
    "y": 10
  }
]