Voice-Activated Wheelchair - Electronic Engineering Guide
1. Introduction
The Voice-Activated Wheelchair is a mobility aid designed to help individuals with physical impairments navigate using voice commands. This project focuses on the design, integration, and control of electronic components that enable voice-based movement.
2. Objectives
• Enable wheelchair movement based on voice commands.
• Provide directional control (forward, backward, left, right, stop).
• Ensure safety, reliability, and ease of use.
• Offer an affordable solution using accessible components.
3. Components Required
• Microcontroller (Arduino Uno or Mega)
• Voice Recognition Module (e.g., Elechouse V3)
• DC Motors with Gearbox (for wheels)
• Motor Driver Module (L298N or BTS7960)
• Battery Pack (12V lead-acid or lithium-ion)
• Wheels and Chassis (wheelchair frame)
• Microphone module (included in voice recognition module)
• Emergency stop switch
• LED indicators (optional)
4. System Overview
The system uses a voice recognition module to interpret spoken commands. The recognized commands are sent to a microcontroller, which controls the motor driver module to move the wheelchair accordingly. Safety features like an emergency stop switch are also integrated.
5. Voice Recognition Module Integration
• Use a reliable voice recognition module with offline
command recognition.
• Train the module with specific commands: 'Forward', 'Backward', 'Left',
'Right', 'Stop'.
• Connect module output to Arduino digital/serial pins.
• Ensure clear voice input and proper noise isolation.
6. Motor Control and Driver Circuits
• Use L298N or BTS7960 motor driver for controlling two DC
motors.
• Connect motor driver inputs to Arduino digital pins.
• Use PWM for speed control (optional).
• Power motors directly from 12V battery.
7. Microcontroller Programming
• Read voice command output from recognition module.
• Use conditional logic to determine direction of movement.
• Control motor driver inputs accordingly.
• Stop or override motion in case of error or emergency input.
8. Power Supply Design
• Use a 12V lead-acid or lithium-ion battery for powering
motors.
• Use a voltage regulator (7805) or buck converter for Arduino (5V).
• Ensure high current rating (motors may draw 2–4A).
9. Safety Features and Fail-safes
• Add an emergency stop switch that cuts power to motors.
• Use current sensors or motor feedback for obstacle detection.
• Implement timeouts in code if no command is received.
• Add manual override for caregiver control.
10. Applications
• Mobility aid for physically challenged individuals
• Smart healthcare systems
• Assistive robotics
• Elderly care applications
11. Limitations and Future Scope
• Limited accuracy in noisy environments.
• Cannot handle complex terrain without additional sensors.
• Future upgrades: Obstacle avoidance using ultrasonic sensors, GPS for
navigation, app-based controls, AI-based speech processing.
12. Conclusion
The voice-activated wheelchair project is a practical example of applying embedded systems and voice control for assistive technology. It enhances mobility, independence, and safety for users through intuitive and accessible controls.