Sensor Data Model¶

The SHM backend organizes physical sensor metadata into a three-level hierarchy: Sensor Type → Sensor → Sensor Calibration.

Entity Hierarchy¶

erDiagram
    SensorType ||--o{ Sensor : "has many"
    Sensor ||--o{ SensorCalibration : "has many"

    SensorType {
        int id PK
        string name
        string manufacturer
        file photo "optional image"
    }

    Sensor {
        int id PK
        int sensor_type_id FK
        string serial_number
        string cabinet
    }

    SensorCalibration {
        int id PK
        int sensor_id FK
        date calibration_date
        file datasheet "optional PDF"
    }

Sensor Types¶

A sensor type represents a product model (e.g. "PCB 393B04 accelerometer"). Each sensor type has a unique name and manufacturer, and can carry an optional photo file.

The SDK uploads sensor types via ShmSensorUploader.upload_sensor_types().

Sensors¶

A sensor is one physical device identified by its serial_number and cabinet (installation location). Every sensor belongs to exactly one sensor type.

The SDK uploads sensors via ShmSensorUploader.upload_sensors().

Sensor Calibrations¶

A sensor calibration records a calibration event for a specific sensor. Each calibration carries a calibration_date and an optional PDF datasheet file.

The SDK uploads sensor calibrations via ShmSensorUploader.upload_sensor_calibrations().

Upload Workflow¶

The three entity types are uploaded in dependency order:

1. Sensor types first — so that sensor type IDs exist for sensor creation.
2. Sensors next — referencing the sensor type by ID.
3. Sensor calibrations last — referencing the sensor by ID.

See the Upload Sensor Types how-to guide for a step-by-step recipe.