OpenAssistive — Technical Specification v1.0

Author: Milton Rodolfo Amador Zúniga
Copyright (C) 2026 Milton Rodolfo Amador Zúniga
License: GNU General Public License v3 (GPLv3)
Non-profit open social technology initiative.

1. Purpose and Scope

Defines a modular, low-cost assistive mobility system to support blind and visually impaired persons. Complements the white cane with sensors, camera reading, haptic and audio feedback.

2. Design Principles

• Low cost
• Modular hardware
• Repairability
• Textile-integrated cabling
• Offline capability
• Open documentation
• GPL licensed software
• Social purpose first

3. System Overview

Modules: Smart Cane Sensor, Shoulder Camera, Backpack Compute, Haptic Feedback, Audio & Voice Interaction.

Flow: Sensors ? Microcontroller ? Compute ? Haptic / Audio Output

4. Main Modules

• Cane sleeve with ToF sensors and MCU
• Handle with button and vibration motor
• Shoulder camera + microphone
• Backpack Raspberry Pi compute unit
• Haptic feedback motors
• Audio headset interface

5. Recommended Components (v1)

• ToF sensors (VL53L1X class)
• ESP32 or RP2040 microcontroller
• Raspberry Pi 4 / 5
• Pi Camera or USB camera
• Coin vibration motors
• 20,000 mAh power bank
• Magnetic safety connectors

6. Electrical Topology

Sensors connect to a microcontroller, which connects to the Raspberry Pi via USB or UART. This improves timing reliability and modularity.

7. Power Budget

Estimated average consumption: 8–12W.
Typical autonomy: 6–10 hours with 20,000 mAh battery.

8. Prototype Phases

1. Sensor sleeve + vibration alerts
2. Microcontroller integration
3. Raspberry Pi connection
4. Camera QR reading
5. Backpack integration
6. User field testing

9. Safety Notes

Assistive only. Does not replace mobility training. Must be tested gradually in controlled environments.

10. Open Contribution Model

Derivatives must remain GPL-compatible. Modifications must be documented.

11. Future Extensions

• GPS assist
• Offline maps
• Object recognition
• Indoor beacons
• Wireless cane module

---

OpenAssistive Project — Open Social Assistive Technology