All case studies
Robotics & AutomationENGINEERING STUDY

On-Device Edge Vision Defect Detection on ESP32-S3

In this embedded systems study, YantriX investigated on-device computer vision inspection running on an ESP32-S3 microcontroller—evaluating INT8 neural inference within a compact low-power footprint for line-side quality checks.

By Tirth Borda · Co-Founder · Robotics Systems Lead2 min readManufacturing Quality Inspection
Compact embedded vision inspection camera for assembly line quality control

Overview

Engineering Scope & Context

Embedded vision study deploying quantized neural networks on a low-cost ESP32-S3 microcontroller to classify surface and assembly defects locally without PC hardware.

Engagement: ENGINEERING STUDY

Discipline: Robotics & Automation

Project Type: Embedded AI (Microcontroller Vision + Quantization Study)

Application: Manufacturing Quality Inspection

YantriX Scope Ownership

  • Camera hardware selection (OV2640 / GC0308) and ESP32-S3 microcontroller circuit integration
  • Dataset collection and annotation of surface defect samples
  • Model training, post-training INT8 quantization, and deployment via ESP-NN
  • Line-side optical trigger sensor integration and status indicator firmware
  • Compact 3D printable fanless enclosure design for mounting at assembly fixtures

Key specifications

Core engineering parameters & stack.

ESP32-S3
Microcontroller Target Architecture
INT8
Quantized Micro Inference Framework
Low Power
Line-Side Workstation Footprint
Self-Contained
Zero PC/Network Infrastructure

Objectives

What the project needed to achieve

  • Implement real-time image capture and inference on an ESP32-S3 module
  • Quantize classification model to INT8 to fit within 512 KB SRAM and flash memory
  • Achieve real-time inspection rates on microcontroller hardware
  • Keep steady-state operational power consumption below 0.5 Watts

Challenge

Engineering constraint

Traditional line-side computer vision inspection relies on expensive industrial PCs, bulky gigabit cameras, and facility network drops. This study evaluated whether recent dual-core microcontrollers with vector instructions (ESP32-S3) can handle localized pass/fail surface inspection directly at the workstation within a low-power, self-contained footprint.

Approach

How YantriX approached the work

  1. 01

    Trained a lightweight MobileNet-derivative architecture on custom industrial part images.

  2. 02

    Applied full integer post-training quantization using TensorFlow Lite for Microcontrollers.

  3. 03

    Utilized ESP-NN optimized vector assembly kernels on the Xtensa LX7 processor cores.

  4. 04

    Designed a compact 40 x 40 x 25 mm snap-fit housing with adjustable mounting brackets.

Outcomes

What improved by the end

  • Demonstrated real-time on-device inference directly on microcontroller hardware
  • Demonstrated low-power steady-state operation during continuous camera and inference cycles
  • Evaluated classification accuracy on laboratory defect test samples
  • Eliminated all external computer and network infrastructure requirements

Deliverables

Engineering Deliverables & Outputs

  • Embedded C++ firmware source code for ESP-IDF
  • Quantized INT8 model files and conversion scripts
  • 3D printable camera bracket and enclosure CAD files
  • Hardware wiring schematic and test evaluation report

Tools used

Stack and tooling

  • ESP32-S3
  • ESP-IDF
  • TensorFlow Lite for Microcontrollers
  • SolidWorks

Impact

Business-level effect

  • Shows the feasibility of deploying standalone TinyML inspection fixtures at manual assembly benches with minimal capital cost

Conclusion

Thoughtful neural network quantization combined with embedded hardware co-design makes real-time computer vision feasible on constrained microcontrollers without requiring expensive PC infrastructure.

Working on a similar engineering problem?

Need compact, low-cost inspection or embedded perception hardware for your assembly workstations? Discuss embedded vision options with our engineers.

Tagged

  • Embedded AI
  • ESP32
  • Computer Vision
  • TinyML
  • Hardware Design

Related case studies

Adjacent proof you can read next.

Continue exploring

Related blogs, services, and capability pages

Explore the engineering service and practical guides related to this work.

Similar Engineering Need?

Need help developing something similar?

Discuss your on-device edge vision defect detection on esp32-s3 requirements, design challenges, or target specifications with our engineering team. NDA support is available where required.