IIT Bombay Develops GPS-Free Swarm Control System for UAVs

Professor Dwaipayan Mukherjee and research scholar Chinmay Garanayak from the Indian Institute of Technology (IIT) Bombay) have developed a new control scheme that allows unmanned aerial vehicles (UAVs) to operate in coordinated swarms without depending on GPS, inter-drone communication, or centralized control systems.

Technology and Methodology

• The system relies on bearing-only measurements captured through onboard cameras to determine relative positions between drones and maintain formation.
• The researchers applied this control method to Vertical Take-Off and Landing (VTOL) UAVs, which can:
  • Lift off without a runway, and
  • Hover mid-air, making them ideal for surveillance and monitoring in confined spaces.

Advantages of the ‘Bearing-Only’ Scheme

• Each drone uses its onboard camera to observe its immediate neighbours and compute bearing information.
• Camera-based measurements are:
  • Less prone to noise compared to conventional distance sensors,
  • Simpler, reducing sensor complexity,
  • More energy-efficient, leading to lower battery usage and reduced drone weight.

Application to VTOL Drones

• The researchers noted that VTOL drones are underactuated systems, meaning:
  • They have six degrees of freedom, but fewer directly controllable movements.
  • While capable of vertical lift and rotation along three axes, lateral and forward-backward motions require indirect control through advanced algorithms.

Source: TH