Archive · IP acquired Nov 2024

AI-Driven Obstacle Detection & Pathfinding for the Visually Impaired Formerly code-named IvoryCane

Navi-Netra fuses an ultrasonic sensor array with real-time CNN/YOLO object detection and A* pathfinding to give visually impaired users proactive, hands-free navigation in both indoor and outdoor environments.

Engineered by Arnav Sharma · Mentor: Sushil Kumar Pandey

Hardware

Device Architecture

Extendable cane form factor with custom-angled smartphone mount (8–9 cm above grip) and protective sensor chassis. Two compute generations were developed.

3D CAD model of Navi-Netra with Raspberry Pi compute unit
Fig 1 — First 3D CAD model (Raspberry Pi as primary compute)
Navi-Netra physical prototype with smartphone mount and ultrasonic sensors
Fig 2 — Production prototype: smartphone edge compute, HC-SR04 array, USB-C power

Ultrasonic Array

  • Multiple HC-SR04 sensors
  • Raw range: 2 cm – 400 cm
  • ±3 mm sensor rating
  • Effective hazard envelope: 0.5 m – 4.0 m
  • ±3 cm precision at 1 m

Compute Evolution

  • Gen 1: Raspberry Pi primary unit (CAD phase)
  • Gen 2: Smartphone edge compute via wired data/power bridge
  • Onboard USB-C power bank
  • 8-hour continuous runtime

Audio & Form Factor

  • Bluetooth low-latency audio relay
  • Extendable cane w/ grip mount
  • Protective sensor chassis at tip
  • Bottom shield for ground-reflection filtering

Empirical Data

Benchmark Results

Human trials with N=10 visually impaired participants. All metrics measured under controlled and real-world field conditions.

94%
Indoor object detection rate
87%
Outdoor unstructured detection
2.5m
Avg proactive hazard alert distance
<4s
End-to-end detection-to-classification latency
MetricValueNotes
Indoor classification accuracy92%Walls, doors, chairs, steps
Outdoor classification accuracy85%Including low-hanging branches, uneven terrain
Preferred over white cane (unfamiliar env.)80%8 of 10 participants
Higher navigation confidence85%Self-reported improvement
Willing to adopt as primary aid78%Post-trial survey
Comfort & weight score8.4 / 10Up to 2 hours continuous use
Overall satisfaction8 / 10Including audio clarity
Proactive alert vs. white cane contact2.5 m vs <1 mAverage hazard detection distance

Software

AI & Sensor-Fusion Pipeline

Real-time object detection and dynamic pathfinding fusing ultrasonic distance telemetry with visual bounding boxes.

01 · CaptureSmartphone camera stream + HC-SR04 ultrasonic distance telemetry
02 · DetectCNN / YOLO real-time object detection — walls, steps, doors, chairs, tree branches
03 · FuseBounding-box geometry merged with ultrasonic range measurements in a spatial map
04 · PathfindA* (A-star) search algorithm computes proactive safe-path routing
05 · AlertLow-latency Bluetooth audio relay delivers spoken turn-by-turn instructions

Research

Technical Whitepaper

Full 20-page research paper covering motivation, literature review, system design, methodology, results, and future scope.

Download PDF ↓