R&DBondstein Technologies Ltd.Work period · 2025-2026High-Speed Lines

Pharma Blister Pack, Cap-Seal & Liquid Fill Inspection

Industrial inspection R&D for blister-pack cavities, cap presence and seating, and liquid fill levels using lightweight geometry and image-processing methods with a queued inference runtime.

Internal R&D / Personal Engineering Project at Bondstein Technologies Ltd.

Module of Bondstein Vision Suite; presented as a separate case study.

Pharma Blister Pack, Cap-Seal & Liquid Fill Inspection project workflow and system architecture
Project workflow and system architecture overview. Open full-size diagram

Workflow at a glance

  1. Acquire line imagery

    Read frames from an inspection camera.

  2. Inspect product regions

    Analyze blister, cap, or fill-level regions.

  3. Apply task rules

    Evaluate configured visual inspection cues.

  4. Review candidates

    Present candidate defects for assessment.

Project facts & reported results

Blister, cap, fill level
Modules

Implementation fact

Reference comparison + geometry + Sobel energy
Methods

Implementation fact

Queued inference runtime
Architecture

Implementation fact

Project Overview

Problem Statement

Packaging inspection must balance defect sensitivity with predictable latency and maintainability on production hardware.

Approach & Methodology

Built lightweight, classical CV modules powered by a shared inference runtime. Implemented grid cavity brightness/fill signature analysis for blister packs, minAreaRect geometry for cap tilt/height, and Sobel row-energy line regression for bottle liquid levels.

Outcome & Scope

Created configurable inspection modules and a micro-batched runtime suitable for controlled line trials and further calibration.

System Architecture

Lock-free microservice inspection suite for industrial packaging lines

Key Components:

CameraWorker

Threaded RTSP/webcam reader with auto-reconnect and per-camera FPS throttling

InferenceServer

Lock-free micro-batched queue managing processing requests without global locks

Blister Cavity Analyzer

Per-cavity brightness and fill signature validation against reference template

Cap Geometry Evaluator

HSV mask + minAreaRect geometry for detecting cocked or elevated caps

Liquid Line Regressor

Sobel row-energy gradient search to measure exact liquid fill level percentage

Key Features & Capabilities

Blister pack cavity brightness & fill signature comparison against auto-learned reference

Cap presence, tilt (cocked cap), and seated height (high cap) geometry analysis

Liquid fill line regression inside bottle ROI using Sobel row-energy

Lock-free micro-batched InferenceServer queue architecture

Config-driven operation requiring zero global model locks

Technologies & Tools

OpenCV
Python
Classical CV
InferenceServer Micro-batch
PyYAML
Sobel Energy