{
  "$schema": "http://json-schema.org/draft-07/schema#",
  "$id": "schemas/joint_module_assembly.schema.json",
  "title": "完整关节模组装配JSON - 填写规范 + 行星关节实例",
  "description": "前部分是Schema填写规范，后部分是具体数据实例",
  "metadata": {
    "author": "设计团队",
    "source": "SolidWorks 2025",
    "version": "1.0",
    "notes": "行星关节模组完整实例，包含joints、verification_rules、power_flow"
  },
  "field_definitions": {
    "_comment_schema": "========== 以下是字段定义（填写说明） ==========",
    "design_id": {
      "type": "string",
      "pattern": "^[A-Z0-9_]+$",
      "required": true,
      "description": "设计唯一标识符",
      "example": "PJ_NGW_S2_090_T80_001",
      "rule": "必须大写字母+数字+下划线"
    },
    "module_type": {
      "type": "string",
      "enum": [
        "planetary",
        "harmonic"
      ],
      "required": true,
      "description": "减速器类型",
      "example": "planetary",
      "rule": "planetary=行星齿轮，harmonic=谐波减速"
    },
    "global_frame": {
      "type": "object",
      "required": true,
      "description": "定义全局坐标系的参考基准。程序读取此字段后，将指定零件的坐标系作为全局坐标系，所有'frame':'global'的关节都基于此坐标系计算运动",
      "example": {
        "reference_part": "Main_case",
        "coordinate_system_name": "MAIN_CSYS",
        "description": "以Main_case零件中的MAIN_CSYS坐标系作为全局坐标系基准"
      },
      "fields": {
        "reference_part": {
          "type": "string",
          "required": true,
          "description": "作为全局坐标系基准的零件id，该零件的坐标系将被映射为全局坐标系"
        },
        "coordinate_system_name": {
          "type": "string",
          "required": true,
          "description": "该零件STEP文件中定义的坐标系名称（在SolidWorks中命名），程序从STEP文件中读取此坐标系"
        },
        "description": {
          "type": "string",
          "description": "说明文字"
        }
      }
    },
    "units": {
      "type": "object",
      "required": true,
      "description": "全局单位声明，所有数值字段必须使用这些单位",
      "example": {
        "length": "mm",
        "angle": "deg",
        "torque": "N_m",
        "mass": "kg",
        "speed": "rpm"
      },
      "fields": {
        "length": {
          "enum": [
            "mm",
            "m",
            "cm"
          ],
          "default": "mm"
        },
        "angle": {
          "enum": [
            "deg",
            "rad"
          ],
          "default": "deg"
        },
        "torque": {
          "enum": [
            "N_m",
            "N_mm",
            "kgf_m"
          ],
          "default": "N_m"
        },
        "mass": {
          "enum": [
            "kg",
            "g",
            "lb"
          ],
          "default": "kg"
        },
        "speed": {
          "enum": [
            "rpm",
            "rad_s",
            "deg_s"
          ],
          "default": "rpm"
        }
      }
    },
    "parts": {
      "type": "array",
      "required": true,
      "description": "零件列表，每个零件一个对象。每个零件对应一个STEP文件，通过coordinate_system字段指定该STEP文件中定义的坐标系名称",
      "minItems": 1,
      "item_fields": {
        "id": {
          "type": "string",
          "required": true,
          "pattern": "^[a-zA-Z][a-zA-Z0-9_]*$",
          "description": "零件唯一标识，其他字段（如constraints、joints）通过此id引用该零件"
        },
        "role": {
          "type": "string",
          "required": true,
          "enum": [
            "stator",
            "rotor",
            "sun_gear",
            "planet_gear",
            "ring_gear",
            "planet_carrier",
            "housing",
            "end_cap",
            "output_flange",
            "bearing",
            "motor_assembly",
            "coupling",
            "shaft",
            "controller_mount",
            "magnet_holder",
            "magnet",
            "bearing_retainer",
            "other"
          ],
          "description": "零件功能角色，用于验证程序识别零件的功能类型"
        },
        "file": {
          "type": "string",
          "required": true,
          "description": "STEP文件路径，相对于JSON文件的路径"
        },
        "coordinate_system": {
          "type": "string",
          "required": true,
          "description": "该零件STEP文件中定义的坐标系名称。程序加载STEP文件时，会读取此名称对应的坐标系作为该零件的局部坐标系。多个零件可引用同一个STEP文件（如多个行星轮），此时应使用相同的坐标系名称",
          "example": "PLANET_CSYS"
        },
        "material": {
          "type": "object",
          "required": true,
          "fields": {
            "class": {
              "enum": [
                "steel",
                "aluminum",
                "plastic",
                "copper",
                "magnet",
                "other"
              ]
            },
            "subclass": {
              "type": "string",
              "description": "材料子类，如20CrMnTi、6061-T6"
            }
          }
        },
        "gear": {
          "type": "object",
          "description": "齿轮参数（齿轮件必填）",
          "fields": {
            "teeth": {
              "type": "integer",
              "minimum": 1
            },
            "module_mm": {
              "type": "number",
              "minimum": 0
            },
            "face_width_mm": {
              "type": "number",
              "minimum": 0
            },
            "pressure_angle_deg": {
              "type": "number",
              "default": 20
            },
            "helix_angle_deg": {
              "type": "number",
              "default": 0
            },
            "gear_type": {
              "enum": [
                "external_gear",
                "internal_gear"
              ]
            }
          }
        },
        "notes": {
          "type": "string",
          "description": "备注说明"
        }
      }
    },
    "constraints": {
      "type": "array",
      "required": true,
      "description": "几何装配约束，程序根据这些约束将分散的STEP零件拼装成完整的模组。约束中的a和b字段可带面名（如'Main_case:Top_Face'）以指定具体几何特征",
      "minItems": 1,
      "item_fields": {
        "type": {
          "enum": [
            "fixed_to_ground",
            "coaxial",
            "coincident",
            "distance",
            "parallel",
            "bearing_support",
            "bolt_pattern",
            "shaft_hub",
            "keyed"
          ],
          "required": true,
          "description": "约束类型：fixed_to_ground=固定于大地，coaxial=同轴，coincident=面贴合，distance=保持距离，parallel=平行，bearing_support=轴承支承，bolt_pattern=螺栓连接，shaft_hub=轴毂连接，keyed=键连接"
        },
        "a": {
          "type": "string",
          "required": true,
          "description": "第一个零件id，可带面名，如'sun_gear:Top_Face'"
        },
        "b": {
          "type": "string",
          "required": true,
          "description": "第二个零件id，可带面名"
        },
        "value_mm": {
          "type": "number",
          "description": "距离类约束的数值（mm）"
        },
        "source": {
          "enum": [
            "sw_mate",
            "manual"
          ],
          "description": "约束来源：sw_mate=来自SolidWorks配合，manual=人工添加"
        },
        "mate_name": {
          "type": "string",
          "description": "SolidWorks配合名称，用于溯源"
        },
        "semantic_hint": {
          "type": "string",
          "description": "自然语言描述约束意图"
        }
      }
    },
    "meshes": {
      "type": "array",
      "required": true,
      "description": "齿轮啮合副（减速器核心），明确声明哪两个齿轮咬合传力。验证程序据此检查中心距、齿侧间隙、干涉等",
      "minItems": 1,
      "item_fields": {
        "pair": {
          "type": "array",
          "minItems": 2,
          "maxItems": 2,
          "required": true,
          "items": {
            "type": "string"
          },
          "description": "啮合的两个齿轮id"
        },
        "type": {
          "enum": [
            "external_gear",
            "internal_gear"
          ],
          "required": true,
          "description": "外啮合或内啮合"
        },
        "center_distance_mm": {
          "type": "number",
          "minimum": 0,
          "required": true,
          "description": "中心距（mm），两个齿轮轴心之间的距离"
        },
        "backlash_mm": {
          "type": "number",
          "minimum": 0,
          "description": "齿侧间隙（mm）"
        },
        "source": {
          "enum": [
            "sw_mate",
            "manual"
          ],
          "description": "啮合来源"
        },
        "semantic_hint": {
          "type": "string",
          "description": "自然语言描述啮合关系"
        }
      }
    },
    "joints": {
      "type": "array",
      "required": true,
      "description": "运动副定义 - 告诉程序零件之间如何相对运动。每个joint定义一对零件之间的相对运动关系，frame字段指定运动轴基于哪个坐标系",
      "minItems": 1,
      "item_fields": {
        "id": {
          "type": "string",
          "required": true,
          "description": "运动副唯一标识"
        },
        "type": {
          "enum": [
            "revolute",
            "fixed",
            "cylindrical",
            "prismatic"
          ],
          "required": true,
          "description": "运动副类型：revolute=旋转副，fixed=固定副（无相对运动），cylindrical=圆柱副（旋转+移动），prismatic=移动副"
        },
        "a": {
          "type": "string",
          "required": true,
          "description": "主动件id（运动件）"
        },
        "b": {
          "type": "string",
          "required": true,
          "description": "从动件/支架id（参考件）"
        },
        "axis": {
          "enum": [
            "x",
            "y",
            "z"
          ],
          "description": "旋转轴方向，基于frame指定的坐标系。与axis_vector二选一使用，优先使用axis_vector"
        },
        "axis_vector": {
          "type": "array",
          "minItems": 3,
          "maxItems": 3,
          "items": {
            "type": "number"
          },
          "description": "方向向量 [x, y, z]，基于frame指定的坐标系。与axis二选一使用，当轴方向不是标准XYZ轴时使用此字段"
        },
        "frame": {
          "type": "string",
          "default": "global",
          "description": "坐标系引用：'global'=使用global_frame定义的全局坐标系；或指定零件id，使用该零件在STEP中定义的坐标系（需在parts中配置coordinate_system字段）"
        },
        "description": {
          "type": "string",
          "description": "自然语言描述运动关系"
        }
      }
    },
    "kinematics": {
      "type": "object",
      "required": true,
      "description": "传动计算参数，定义减速器的类型和传动比。验证程序据此校核传动比是否与齿数自洽",
      "fields": {
        "type": {
          "enum": [
            "planetary",
            "harmonic"
          ],
          "required": true,
          "description": "减速器类型"
        },
        "planet_count": {
          "type": "integer",
          "minimum": 1,
          "description": "行星轮数量（行星专用）"
        },
        "fixed_member": {
          "enum": [
            "ring_gear",
            "carrier",
            "sun_gear"
          ],
          "description": "固定件（行星专用）：ring_gear=齿圈固定，carrier=行星架固定，sun_gear=太阳轮固定"
        },
        "ratio_claimed": {
          "type": "number",
          "minimum": 0,
          "required": true,
          "description": "声称的传动比（输入转速/输出转速）"
        },
        "ratio_formula": {
          "type": "string",
          "description": "传动比计算公式说明（人类可读）"
        },
        "ratio_derived": {
          "type": "object",
          "description": "机器可读的派生计算，程序可据此自动校验传动比",
          "fields": {
            "formula": {
              "type": "string",
              "description": "表达式，引用parts中的齿轮参数，如'(ring_gear.teeth + sun_gear.teeth) / sun_gear.teeth'"
            },
            "input_params": {
              "type": "array",
              "items": {
                "type": "string"
              },
              "description": "表达式中引用的零件id列表"
            }
          }
        },
        "notes": {
          "type": "string",
          "description": "备注"
        }
      }
    },
    "verification_rules": {
      "type": "object",
      "required": true,
      "description": "程序可执行的验证规则。程序解析expression字段中的表达式，计算出结果后与expected或compare_to对比，判断设计是否合理",
      "fields": {
        "ratio": {
          "type": "array",
          "description": "传动比验证规则",
          "item_fields": {
            "rule_id": {
              "type": "string",
              "description": "规则唯一标识"
            },
            "expression": {
              "type": "string",
              "description": "计算公式，引用parts中的齿轮参数"
            },
            "expected": {
              "type": "number",
              "description": "期望值"
            },
            "tolerance": {
              "type": "number",
              "default": 0.01,
              "description": "允许偏差"
            },
            "description": {
              "type": "string",
              "description": "规则说明"
            }
          }
        },
        "torque": {
          "type": "array",
          "description": "扭矩验证规则",
          "item_fields": {
            "rule_id": {
              "type": "string"
            },
            "expression": {
              "type": "string",
              "description": "扭矩计算公式"
            },
            "compare_to": {
              "type": "string",
              "description": "对比目标字段，如'targets.rated_torque_nm'"
            },
            "description": {
              "type": "string"
            }
          }
        },
        "geometry": {
          "type": "array",
          "description": "几何验证规则，如中心距校验、齿数关系校验",
          "item_fields": {
            "rule_id": {
              "type": "string"
            },
            "expression": {
              "type": "string",
              "description": "几何计算公式"
            },
            "compare_to": {
              "type": "string",
              "description": "对比目标"
            },
            "tolerance": {
              "type": "number",
              "description": "允许偏差"
            },
            "description": {
              "type": "string"
            }
          }
        }
      }
    },
    "power_flow": {
      "type": "object",
      "required": true,
      "description": "动力传输路径，声明动力从哪个零件输入、经过哪些零件、最终输出到哪个零件",
      "fields": {
        "path": {
          "type": "array",
          "items": {
            "type": "string"
          },
          "description": "动力流经的零件id顺序"
        },
        "efficiency": {
          "type": "number",
          "minimum": 0,
          "maximum": 1,
          "description": "传输效率（0~1）"
        },
        "coupling_type": {
          "enum": [
            "direct",
            "coupling",
            "keyed",
            "spline"
          ],
          "description": "连接方式"
        },
        "notes": {
          "type": "string",
          "description": "备注"
        }
      }
    },
    "io": {
      "type": "object",
      "required": true,
      "description": "输入/输出/固定定义，明确整机的动力流向和约束边界",
      "fields": {
        "ground": {
          "type": "array",
          "items": {
            "type": "string"
          },
          "description": "相对大地固定的零件id列表"
        },
        "input": {
          "type": "string",
          "description": "动力输入零件id"
        },
        "output": {
          "type": "string",
          "description": "动力输出零件id"
        },
        "dof_expected": {
          "type": "string",
          "description": "期望的自由度描述，如'输出法兰绕Z轴旋转'"
        },
        "notes": {
          "type": "string",
          "description": "备注"
        }
      }
    },
    "motor_spec": {
      "type": "object",
      "required": true,
      "description": "电机规格参数，用于扭矩、功率、气隙等验证。早期可填估算值，但必须注明来源",
      "fields": {
        "motor_type": {
          "type": "string",
          "description": "电机类型，如bldc、pmsm"
        },
        "rated_torque_nm": {
          "type": "number",
          "description": "电机额定扭矩（N·m）"
        },
        "peak_torque_nm": {
          "type": "number",
          "description": "电机峰值扭矩（N·m）"
        },
        "rated_speed_rpm": {
          "type": "number",
          "description": "电机额定转速（rpm）"
        },
        "pole_pairs": {
          "type": "integer",
          "description": "电机极对数"
        },
        "air_gap_target_mm": {
          "type": "number",
          "description": "气隙目标值（mm）"
        },
        "air_gap_tol_mm": {
          "type": "number",
          "description": "气隙允许公差（mm）"
        },
        "voltage_v": {
          "type": "number",
          "description": "额定电压（V）"
        },
        "max_current_a": {
          "type": "number",
          "description": "最大电流（A）"
        },
        "assumption_notes": {
          "type": "string",
          "description": "参数来源说明，如'待台架标定'、'参考手册'等"
        }
      }
    },
    "targets": {
      "type": "object",
      "required": true,
      "description": "整机性能及格线，是验证程序判断设计是否通过的标准",
      "fields": {
        "rated_torque_nm": {
          "type": "number",
          "description": "输出端额定扭矩目标（N·m）"
        },
        "peak_torque_nm": {
          "type": "number",
          "description": "输出端峰值扭矩目标（N·m）"
        },
        "ratio": {
          "type": "number",
          "description": "目标传动比"
        },
        "max_od_mm": {
          "type": "number",
          "description": "最大外径限制（mm）"
        },
        "max_length_mm": {
          "type": "number",
          "description": "最大长度限制（mm）"
        },
        "max_mass_kg": {
          "type": "number",
          "description": "最大重量限制（kg）"
        },
        "max_temp_rise_c": {
          "type": "number",
          "description": "允许最大温升（°C）"
        }
      }
    }
  },
  "_comment_data_start": "========== 以下是具体数据实例（行星关节模组） ==========",
  "design_id": "PJ_NGW_S2_090_T80_001",
  "module_type": "planetary",
  "version": "1.0",
  "created_date": "2026-08-07",
  "global_frame": {
    "reference_part": "gear_housing",
    "coordinate_system_name": "HOUSING_CSYS",
    "description": "以减速器壳体HOUSING_CSYS作为全局坐标系基准"
  },
  "units": {
    "length": "mm",
    "angle": "deg",
    "torque": "N_m",
    "mass": "kg",
    "speed": "rpm"
  },
  "requirement_text": "行星齿轮模组，包含电机、行星减速器、外壳，输出端目标扭矩80N·m，最大外径≤150mm，总长≤120mm，总重≤2kg",
  "parts": [
      {"id": "motor_stator", "role": "motor_stator", "file": "零件/motor_stator.step", "coordinate_system": "STATOR_CSYS", "material": {"class": "aluminum"}, "notes": "电机定子，坐标系定义在定子轴线上"},
      {"id": "motor_rotor", "role": "motor_rotor", "file": "零件/motor_rotor.step", "coordinate_system": "ROTOR_CSYS", "material": {"class": "steel"}, "notes": "电机转子，坐标系定义在转子输出轴线上"},
      {"id": "sun_gear", "role": "sun_gear", "file": "零件/sun_gear.step", "coordinate_system": "SUN_CSYS", "material": {"class": "steel"}, "gear": {"teeth": 19, "module_mm": 2.5, "face_width_mm": 8, "pressure_angle_deg": 20, "helix_angle_deg": 0, "gear_type": "external_gear"}, "notes": "太阳轮，坐标系定义在分度圆中心"},
      {"id": "planet_gear_1", "role": "planet_gear", "file": "零件/planet_gear.step", "coordinate_system": "PLANET_CSYS", "material": {"class": "steel"}, "gear": {"teeth": 17, "module_mm": 2.5, "face_width_mm": 4, "pressure_angle_deg": 20, "helix_angle_deg": 0, "gear_type": "external_gear"}, "notes": "行星轮1，坐标系定义在自转轴线上"},
      {"id": "planet_gear_2", "role": "planet_gear", "file": "零件/planet_gear.step", "coordinate_system": "PLANET_CSYS", "material": {"class": "steel"}, "gear": {"teeth": 17, "module_mm": 2.5, "face_width_mm": 4, "pressure_angle_deg": 20, "helix_angle_deg": 0, "gear_type": "external_gear"}, "notes": "行星轮2，坐标系定义在自转轴线上"},
      {"id": "planet_gear_3", "role": "planet_gear", "file": "零件/planet_gear.step", "coordinate_system": "PLANET_CSYS", "material": {"class": "steel"}, "gear": {"teeth": 17, "module_mm": 2.5, "face_width_mm": 4, "pressure_angle_deg": 20, "helix_angle_deg": 0, "gear_type": "external_gear"}, "notes": "行星轮3，坐标系定义在自转轴线上"},
      {"id": "ring_gear", "role": "ring_gear", "file": "零件/ring_gear.step", "coordinate_system": "RING_CSYS", "material": {"class": "steel"}, "gear": {"teeth": 53, "module_mm": 2.5, "face_width_mm": 4, "pressure_angle_deg": 20, "helix_angle_deg": 0, "gear_type": "internal_gear"}, "notes": "内齿圈，坐标系定义在齿圈自转轴线上"},
      {"id": "planet_gear_bearing_1", "role": "bearing", "file": "零件/planet_gear_bearing.step", "coordinate_system": "BEARING_CSYS", "material": {"class": "steel"}, "notes": "行星轮1轴承，坐标系定义在轴承中轴线"},
      {"id": "planet_gear_bearing_2", "role": "bearing", "file": "零件/planet_gear_bearing.step", "coordinate_system": "BEARING_CSYS", "material": {"class": "steel"}, "notes": "行星轮2轴承，坐标系定义在轴承中轴线"},
      {"id": "planet_gear_bearing_3", "role": "bearing", "file": "零件/planet_gear_bearing.step", "coordinate_system": "BEARING_CSYS", "material": {"class": "steel"}, "notes": "行星轮3轴承，坐标系定义在轴承中轴线"},
      {"id": "carrier", "role": "carrier", "file": "零件/carrier.step", "coordinate_system": "CARRIER_CSYS", "material": {"class": "steel"}, "notes": "行星架，坐标系定义在输出轴线上"},
      {"id": "carrier_bearing", "role": "bearing_seat", "file": "零件/carrier_bearing.step", "coordinate_system": "CARRIER_BEARING_CSYS", "material": {"class": "other"}, "notes": "行星架主轴承，坐标系定义在轴承中轴线上"},
      {"id": "gear_housing", "role": "gear_housing", "file": "零件/gear_housing.step", "coordinate_system": "HOUSING_CSYS", "material": {"class": "aluminum"}, "notes": "减速器壳体，坐标系HOUSING_CSYS作为全局基准"},
      {"id": "back_plate", "role": "output_flange", "file": "零件/back_plate.step", "coordinate_system": "BACKPLATE_CSYS", "material": {"class": "aluminum"}, "notes": "后端盖/输出法兰，坐标系定义在端盖中心"},
      {"id": "seal_cover", "role": "seal_cover", "file": "零件/seal_cover.step", "coordinate_system": "SEAL_COVER_CSYS", "material": {"class": "aluminum"}, "notes": "密封盖，坐标系定义在密封盖中心"}
    ],

  "constraints": [
      {"type": "fixed_to_ground", "a": "gear_housing", "source": "sw_mate", "semantic_hint": "电机外壳固定于机座"},
      {"type": "coaxial", "a": "motor_rotor:Outer_Cyl", "b": "motor_stator:Outer_Cyl", "source": "sw_mate", "mate_name": "Rotor_Stator_Coaxial", "semantic_hint": "转子外圆柱面与定子外圆柱面同轴"},
      {"type": "coincident", "a": "motor_rotor:Bottom_Face", "b": "motor_stator:Bottom_Step", "source": "sw_mate", "mate_name": "Rotor_Stator_Coincident", "semantic_hint": "转子下平面与定子下台阶面重合"},
      {"type": "coincident", "a": "motor_stator:Top_Face", "b": "back_plate:Bottom_Face", "source": "sw_mate", "mate_name": "Motor_BackPlate_Coincident", "semantic_hint": "电机上平面与后盖下平面重合"},
      {"type": "coaxial", "a": "motor_stator:Threaded_Hole_1", "b": "back_plate:Threaded_Hole_1", "source": "sw_mate", "mate_name": "Motor_BackPlate_Hole1_Coaxial", "semantic_hint": "电机与后盖螺纹孔1同轴"},
      {"type": "coaxial", "a": "back_plate:Outer_Cyl", "b": "gear_housing:Outer_Cyl", "source": "sw_mate", "mate_name": "BackPlate_Housing_Coaxial", "semantic_hint": "后盖外圆柱面与壳体外圆柱面同轴"},
      {"type": "coincident", "a": "back_plate:Top_Face", "b": "gear_housing:Top_Face", "source": "sw_mate", "mate_name": "BackPlate_Housing_Top_Coincident", "semantic_hint": "后盖上平面与壳体上平面重合"},
      {"type": "coaxial", "a": "back_plate:Side_Hole_1", "b": "gear_housing:Side_Hole_1", "source": "sw_mate", "mate_name": "BackPlate_Housing_SideHole1_Coaxial", "semantic_hint": "后盖与壳体侧边螺纹孔1同轴"},
      {"type": "coaxial", "a": "sun_gear:Inner_Cyl", "b": "motor_rotor:Output_Shaft_Outer_Cyl", "source": "sw_mate", "mate_name": "SunGear_Rotor_Coaxial", "semantic_hint": "太阳轮内圆柱面与电机转子输出轴外圆柱面同轴"},
      {"type": "coincident", "a": "sun_gear:Bottom_Face", "b": "motor_rotor:Output_Shaft_Bottom_Face", "source": "sw_mate", "mate_name": "SunGear_Rotor_Coincident", "semantic_hint": "太阳轮下平面与电机转子输出轴下平面重合"},
      {"type": "coaxial", "a": "ring_gear:Outer_Cyl", "b": "gear_housing:Inner_Cyl", "source": "sw_mate", "mate_name": "RingGear_Motor_Coaxial", "semantic_hint": "齿圈外圆柱面与电机壳体内圆柱面重合"},
      {"type": "coincident", "a": "ring_gear:Bottom_Face", "b": "gear_housing:Step_Face", "source": "sw_mate", "mate_name": "RingGear_Motor_Step_Coincident", "semantic_hint": "齿圈下平面与电机外壳台阶面重合"},
      {"type": "coaxial", "a": "ring_gear:Threaded_Hole_1", "b": "motor_stator:Threaded_Hole_1", "source": "sw_mate", "mate_name": "RingGear_Motor_Hole_Coaxial", "semantic_hint": "齿圈螺纹孔与电机定子螺纹孔同轴"},
      {"type": "coaxial", "a": "planet_gear_bearing_1:Outer_Cyl", "b": "planet_gear_1:Inner_Cyl", "source": "sw_mate", "mate_name": "Bearing1_Gear1_Coaxial", "semantic_hint": "行星轮1轴承外圆柱面与行星轮1内圆柱面重合"},
      {"type": "coincident", "a": "planet_gear_bearing_1:Step_Face", "b": "planet_gear_1:Step_Face", "source": "sw_mate", "mate_name": "Bearing1_Gear1_Step_Coincident", "semantic_hint": "行星轮1轴承台阶面与行星轮1台阶面重合"},
      {"type": "coaxial", "a": "planet_gear_bearing_1:Inner_Cyl", "b": "carrier:Small_Cyl_1", "source": "sw_mate", "mate_name": "Bearing1_Carrier_Coaxial", "semantic_hint": "行星轮1轴承内圆柱面与行星架小圆柱面1同心"},
      {"type": "coincident", "a": "planet_gear_bearing_1:Bottom_Face", "b": "carrier:Top_Face", "source": "sw_mate", "mate_name": "Bearing1_Carrier_Coincident", "semantic_hint": "行星轮1轴承下平面与行星架上平面1重合"},
      {"type": "coaxial", "a": "planet_gear_bearing_2:Outer_Cyl", "b": "planet_gear_2:Inner_Cyl", "source": "sw_mate", "mate_name": "Bearing2_Gear2_Coaxial", "semantic_hint": "行星轮2轴承外圆柱面与行星轮2内圆柱面重合"},
      {"type": "coincident", "a": "planet_gear_bearing_2:Step_Face", "b": "planet_gear_2:Step_Face", "source": "sw_mate", "mate_name": "Bearing2_Gear2_Step_Coincident", "semantic_hint": "行星轮2轴承台阶面与行星轮2台阶面重合"},
      {"type": "coaxial", "a": "planet_gear_bearing_2:Inner_Cyl", "b": "carrier:Small_Cyl_2", "source": "sw_mate", "mate_name": "Bearing2_Carrier_Coaxial", "semantic_hint": "行星轮2轴承内圆柱面与行星架小圆柱面2同心"},
      {"type": "coincident", "a": "planet_gear_bearing_2:Bottom_Face", "b": "carrier:Top_Face", "source": "sw_mate", "mate_name": "Bearing2_Carrier_Coincident", "semantic_hint": "行星轮2轴承下平面与行星架上平面2重合"},
      {"type": "coaxial", "a": "planet_gear_bearing_3:Outer_Cyl", "b": "planet_gear_3:Inner_Cyl", "source": "sw_mate", "mate_name": "Bearing3_Gear3_Coaxial", "semantic_hint": "行星轮3轴承外圆柱面与行星轮3内圆柱面重合"},
      {"type": "coincident", "a": "planet_gear_bearing_3:Step_Face", "b": "planet_gear_3:Step_Face", "source": "sw_mate", "mate_name": "Bearing3_Gear3_Step_Coincident", "semantic_hint": "行星轮3轴承台阶面与行星轮3台阶面重合"},
      {"type": "coaxial", "a": "planet_gear_bearing_3:Inner_Cyl", "b": "carrier:Small_Cyl_3", "source": "sw_mate", "mate_name": "Bearing3_Carrier_Coaxial", "semantic_hint": "行星轮3轴承内圆柱面与行星架小圆柱面3同心"},
      {"type": "coincident", "a": "planet_gear_bearing_3:Bottom_Face", "b": "carrier:Top_Face", "source": "sw_mate", "mate_name": "Bearing3_Carrier_Coincident", "semantic_hint": "行星轮3轴承下平面与行星架上平面3重合"},
      {"type": "coaxial", "a": "carrier_bearing:Outer_Cyl", "b": "gear_housing:Bearing_Inner_Cyl", "source": "sw_mate", "mate_name": "CarrierBearing_Motor_Coaxial", "semantic_hint": "行星架轴承外圆柱面与电机外壳内圆柱面重合"},
      {"type": "coincident", "a": "carrier_bearing:Top_Face", "b": "gear_housing:Bottom_Step", "source": "sw_mate", "mate_name": "CarrierBearing_Motor_Coincident", "semantic_hint": "行星架轴承上平面与电机外壳下台阶面重合"},
      {"type": "coaxial", "a": "carrier:Outer_Cyl", "b": "carrier_bearing:Inner_Cyl", "source": "sw_mate", "mate_name": "Carrier_CarrierBearing_Coaxial", "semantic_hint": "行星架外圆柱面与行星架轴承内圆柱面重合"},
      {"type": "coincident", "a": "planet_gear_1:Top_Face", "b": "ring_gear:Top_Face", "source": "sw_mate", "mate_name": "PlanetGear1_RingGear_Coincident", "semantic_hint": "行星轮1上平面与齿圈上平面重合"},
      {"type": "coincident", "a": "seal_cover:Top_Face", "b": "gear_housing:Bottom_Face", "source": "sw_mate", "mate_name": "SealCover_Motor_Coincident", "semantic_hint": "密封盖上平面与电机外壳下平面重合"},
      {"type": "coaxial", "a": "seal_cover:Outer_Cyl", "b": "gear_housing:Outer_Cyl", "source": "sw_mate", "mate_name": "SealCover_Motor_Coaxial", "semantic_hint": "密封盖外圆柱面与电机外壳外圆柱面同轴"},
      {"type": "coaxial", "a": "seal_cover:Threaded_Hole_1", "b": "gear_housing:Bottom_Hole_1", "source": "sw_mate", "mate_name": "SealCover_Motor_Hole1_Coaxial", "semantic_hint": "密封盖与电机外壳螺纹孔1同轴"}
    ],
  "meshes": [
      {"pair": ["sun_gear", "planet_gear_1"], "type": "external_gear", "center_distance_mm": 45,  "source": "sw_mate", "semantic_hint": "太阳轮与行星轮1外啮合"},
      {"pair": ["sun_gear", "planet_gear_2"], "type": "external_gear", "center_distance_mm": 45,  "source": "sw_mate", "semantic_hint": "太阳轮与行星轮2外啮合"},
      {"pair": ["sun_gear", "planet_gear_3"], "type": "external_gear", "center_distance_mm": 45,  "source": "sw_mate", "semantic_hint": "太阳轮与行星轮3外啮合"},
      {"pair": ["ring_gear", "planet_gear_1"], "type": "internal_gear", "center_distance_mm": 45,  "source": "sw_mate", "semantic_hint": "齿圈与行星轮1内啮合"},
      {"pair": ["ring_gear", "planet_gear_2"], "type": "internal_gear", "center_distance_mm": 45,  "source": "sw_mate", "semantic_hint": "齿圈与行星轮2内啮合"},
      {"pair": ["ring_gear", "planet_gear_3"], "type": "internal_gear", "center_distance_mm": 45,  "source": "sw_mate", "semantic_hint": "齿圈与行星轮3内啮合"}
    ],

  "joints": [
      {"id": "joint_sun_gear", "type": "revolute", "a": "sun_gear", "b": "gear_housing", "axis": "z", "frame": "global", "description": "太阳轮相对于壳体绕全局Z轴旋转"},
      {"id": "joint_carrier_output", "type": "revolute", "a": "carrier", "b": "gear_housing", "axis": "z", "frame": "global", "description": "行星架（输出端）相对于壳体绕全局Z轴旋转"},
      {"id": "joint_carrier_planet_1", "type": "revolute", "a": "planet_gear_1", "b": "gear_housing", "axis": "z", "frame": "global", "description": "行星轮1随行星架绕全局Z轴公转"},
      {"id": "joint_carrier_planet_2", "type": "revolute", "a": "planet_gear_2", "b": "gear_housing", "axis": "z", "frame": "global", "description": "行星轮2随行星架绕全局Z轴公转"},
      {"id": "joint_carrier_planet_3", "type": "revolute", "a": "planet_gear_3", "b": "gear_housing", "axis": "z", "frame": "global", "description": "行星轮3随行星架绕全局Z轴公转"},
      {"id": "joint_planet_1", "type": "revolute", "a": "planet_gear_1", "b": "carrier", "axis": "z", "frame": "PLANET_CSYS", "description": "行星轮1相对于行星架绕自身Z轴自转"},
      {"id": "joint_planet_2", "type": "revolute", "a": "planet_gear_2", "b": "carrier", "axis": "z", "frame": "PLANET_CSYS", "description": "行星轮2相对于行星架绕自身Z轴自转"},
      {"id": "joint_planet_3", "type": "revolute", "a": "planet_gear_3", "b": "carrier", "axis": "z", "frame": "PLANET_CSYS", "description": "行星轮3相对于行星架绕自身Z轴自转"},
      {"id": "joint_fixed_ring", "type": "fixed", "a": "ring_gear", "b": "gear_housing", "axis": "z", "frame": "global", "description": "齿圈固定于主框架，不旋转"}
    ],
  "kinematics": {
    "type": "planetary",
    "planet_count": 3,
    "fixed_member": "ring_gear",
    "ratio_claimed": 3.7895,
    "ratio_formula": "(ring_gear_teeth + sun_gear_teeth) / sun_gear_teeth = (100 + 20) / 20 = 6.0",
    "ratio_derived": {
      "formula": "(ring_gear.teeth + sun_gear.teeth) / sun_gear.teeth",
      "input_params": [
        "ring_gear",
        "sun_gear"
      ]
    },
    "notes": "齿圈固定(T80)，太阳轮输入(约T20)，行星架输出，理论传动比3.7895:1"
  },
  "verification_rules": {
    "ratio": [
      {
        "rule_id": "ratio_check",
        "expression": "(ring_gear.teeth + sun_gear.teeth) / sun_gear.teeth",
        "expected": 3.7895,
        "tolerance": 0.01,
        "description": "齿圈固定时，传动比=(Zr+Zs)/Zs"
      }
    ],
    "torque": [
      {
        "rule_id": "torque_output_check",
        "expression": "motor_spec.rated_torque_nm * kinematics.ratio_claimed * power_flow.efficiency",
        "compare_to": "targets.rated_torque_nm",
        "description": "输出扭矩=电机扭矩×传动比×效率"
      }
    ],
    "geometry": [
      {
        "rule_id": "center_distance_check",
        "expression": "(sun_gear.gear.teeth + planet_gear_1.gear.teeth) * sun_gear.gear.module_mm / 2",
        "compare_to": "meshes[0].center_distance_mm",
        "tolerance": 0.05,
        "description": "理论中心距=(Zs+Zp)×m/2"
      },
      {
        "rule_id": "ring_gear_teeth_check",
        "expression": "sun_gear.gear.teeth + 2 * planet_gear_1.gear.teeth",
        "compare_to": "ring_gear.gear.teeth",
        "description": "齿圈齿数=Zs+2×Zp"
      }
    ]
  },
  "power_flow": {
    "path": [
      "motor",
      "motor_to_sun_gear_coupling",
      "sun_gear"
    ],
    "efficiency": 0.97,
    "coupling_type": "coupling",
    "notes": "电机→联轴器→太阳轮，效率按97%估算"
  },
  "io": {
    "ground": [
      "motor_stator",
      "ring_gear",
      "gear_housing"
    ],
    "input": "motor_rotor",
    "output": "carrier",
    "dof_expected": "行星架绕Z轴旋转",
    "notes": "电机转子驱动太阳轮，行星架输出；定子、齿圈、壳体固定"
  },
  "motor_spec": {
    "motor_type": "bldc",
    "rated_torque_nm": 20,
    "peak_torque_nm": 35,
    "rated_speed_rpm": 3000,
    "pole_pairs": 7,
    "air_gap_target_mm": 0.5,
    "air_gap_tol_mm": 0.1,
    "voltage_v": 24,
    "max_current_a": 15,
    "assumption_notes": "3500电机：额定扭矩2.0N·m@3000rpm，峰值4.0N·m，气隙0.5mm"
  },
  "targets": {
    "rated_torque_nm": 80,
    "peak_torque_nm": 100,
    "ratio": 3.7895,
    "max_od_mm": 150,
    "max_length_mm": 120,
    "max_mass_kg": 2,
    "max_temp_rise_c": 60
  }
}