packing — defect_detection (efficientad-label-presence)
Physics
Section titled “Physics”A camera inspects packed cartons on the packing line for label/seal presence and placement defects: a missing label, a skewed label, or a missing seal. efficientad is a lighter-weight anomaly model than patchcore (a compact student-teacher network trained only on known-good carton images rather than a large nearest-neighbour memory bank), so it is chosen here specifically because the packing line runs faster than the moulding and stamping stations in the other two defect recipes and needs lower per-frame inference latency to keep up without falling behind the line. The inspection Zone covers the carton’s label-bearing face as it passes the inspection point. A diffuse backlight-free ring light is used to give even illumination across both the label’s printed surface and the carton’s bare cardboard, since label edges and seal tape need consistent contrast to score reliably, not silhouette separation. At a line speed of up to 60 cartons/min with a minimum gap of 150 mm at 0.3 m/s belt speed, each carton’s label face is in frame for ~0.5 s; a photo-eye trigger fires one capture per carton as it reaches the inspection point so exactly one frame is scored per carton regardless of small line-speed variation, rather than relying on free-running capture to happen to catch each carton square-on.
Sensor
Section titled “Sensor”- Spec: industrial GigE/PoE area-scan camera with fixed-focal C-mount lens and diffuse LED ring light, photo-eye-triggered single-frame capture, global shutter
- Signal: state (1), range n/a
Example parts
Section titled “Example parts”- Teledyne FLIR Blackfly S BFS-PGE-16S2C-CS GigE PoE camera with 8mm C-mount lens, HW trigger input
- Basler ace 2 a2A1920-51gcPRO GigE area-scan camera (1920x1200, global shutter, PoE)
- Banner Engineering QS18VP6D through-beam photoelectric pair (trigger sensor, 18mm barrel, PNP NO)
Mounting
Section titled “Mounting”Mount the camera on a rigid bracket beside or above the packing line, square-on to the carton’s label-bearing face as it passes the inspection point, at a working distance that frames the full label area with margin for carton-to-carton position variation. Mount the ring light coaxially with the lens. Mount the trigger photo-eye just upstream of the camera’s field of view so the carton is centered in frame when the trigger fires.
Wiring
Section titled “Wiring”Camera connects via PoE Ethernet to the edge box’s GigE Vision NIC; the trigger photo-eye’s digital output is wired to the edge box’s digital trigger input, firing the camera and ring light together; route trigger and camera cabling away from the belt drive and any package-sealing equipment to avoid induced noise on the trigger edge.
Validation
Section titled “Validation”run 50 correctly-labelled cartons and a set of deliberately defective cartons (missing label, skewed label, missing seal) through the inspection point and compare flagged/not-flagged against a human QC sort
Expected: correctly-labelled cartons score below score_threshold on >=98% of frames; each seeded defect class is flagged; re-tune score_threshold against the good-carton score distribution if label stock or print contrast changes
Safety notes
Section titled “Safety notes”- lock out/stop the line (LOTO) while mounting camera, light, and trigger photo-eye brackets near the moving conveyor or sealing equipment
- rigidly secure the camera and ring-light brackets; an unsecured overhead bracket is a falling-object hazard onto operators below
- electrical safety for PoE camera cabling, ring-light power wiring, and trigger photo-eye wiring routed near the belt drive and sealing equipment
450–1700 USD, difficulty 3/5, ~60 min install downtime.