Underwater Drones and Surveillance Systems | Science & Technology for UPSC CSE PDF Download

Introduction

Underwater drones, also known as Unmanned Underwater Vehicles (UUVs) or Autonomous Underwater Vehicles (AUVs), and associated surveillance systems are advanced technologies transforming maritime defence, exploration, and security. These systems leverage robotics, artificial intelligence (AI), and sensor technologies to operate autonomously or remotely in underwater environments, performing tasks like surveillance, reconnaissance, mine detection, and oceanographic research. As of August 2025, underwater drones are critical for maritime powers, including India, to secure strategic waters like the Indian Ocean Region (IOR) amid rising tensions with China and Pakistan. 

Fundamentals of Underwater Drones and Surveillance Systems

• Core Principles:

  • Underwater Drones (UUVs/AUVs): Unmanned vehicles designed for underwater operations, equipped with propulsion systems, sensors, and AI for autonomous or remote control. They operate in challenging environments with high pressure, low visibility, and communication constraints.

  • Surveillance Systems: Integrated sensor suites (sonar, LIDAR, cameras) and communication technologies (acoustic modems) for real-time data collection and transmission.

  • Autonomy Levels: Range from remotely operated vehicles (ROVs) requiring human control to fully autonomous AUVs using AI for decision-making.

• Key Technologies:

  • Sensors: Sonar (active/passive for mapping and detection), hydrophones (sound detection), magnetometers (metal detection), and optical cameras.

  • Propulsion: Electric thrusters or propellers; some use biomimetic designs (e.g., fin-like movements).

  • Communication: Acoustic signals for underwater data transfer, as radio waves are ineffective; surface relays for satellite/uplink connectivity.

  • AI and Machine Learning: Enable real-time target identification, navigation in GPS-denied environments, and data processing.

• Advantages:

  • Access to hazardous or inaccessible areas (e.g., deep-sea trenches, minefields).

  • Reduced risk to human divers in surveillance or combat operations.

  • Cost-effective for long-duration missions compared to manned vessels.

• Limitations:

  • Limited battery life (typically 6–24 hours for AUVs).

  • Slow data transmission due to acoustic communication constraints.

  • High development and maintenance costs.

Types of Underwater Drones

• Remotely Operated Vehicles (ROVs): Tethered to a surface vessel, controlled by human operators. Used for tasks like deep-sea inspections (e.g., pipeline maintenance). Example: US Navy’s REMUS 600.

• Autonomous Underwater Vehicles (AUVs): Operate without tethers, using pre-programmed missions or AI. Suited for long-range surveillance. Example: Boeing’s Orca XLUUV.

• Gliders: Low-power AUVs that use buoyancy changes to glide, ideal for oceanographic data collection over months. Example: Slocum Glider.

• Hybrid UUVs: Combine ROV and AUV capabilities for flexibility. Example: China’s Haiyan glider with modular payloads.

• Swarm UUVs: Coordinated groups of small drones for collective tasks like wide-area surveillance or mine countermeasures.

Applications in Defence

• Maritime Surveillance and Reconnaissance:

  • Monitor territorial waters, exclusive economic zones (EEZs), and choke points (e.g., Malacca Strait).

  • Detect submarines, mines, or illicit activities (e.g., smuggling, illegal fishing).

• Anti-Submarine Warfare (ASW):

  • Track enemy submarines using sonar and AI-driven pattern recognition. Example: US Navy’s Sea Hunter tracks diesel-electric submarines.

  • Deploy sonobuoys or torpedoes autonomously.

• Mine Countermeasures (MCM):

  • Detect and neutralize sea mines using sonar and robotic arms. Example: Norway’s HUGIN AUV for mine hunting.

• Undersea Infrastructure Protection:

  • Secure underwater cables, pipelines, and offshore platforms from sabotage.

  • Monitor critical assets like India’s offshore oil rigs in the Arabian Sea.

• Search and Rescue:

  • Locate sunken vessels, aircraft, or personnel in disaster scenarios.

• Electronic Warfare:

  • Deploy decoys or jammers to disrupt enemy sonar or communications.

Global Developments in Underwater Drones and Surveillance

• United States:

  • Leads with programs like the Orca Extra-Large UUV (XLUUV), deployed in 2024 for long-range ASW and ISR.

  • Sea Hunter (Medium Displacement USV) integrates with UUVs for networked operations.

  • Budget: $500 million in FY2025 for UUV development; DARPA’s Manta Ray program tests stealth AUVs.

• China:

  • Rapidly expanding UUV fleet, including HSU-001 (large AUV) and Haiyan gliders for South China Sea surveillance.

  • Deployed swarm UUVs in 2025 exercises, enhancing A2/AD (anti-access/area denial) capabilities.

  • Operates underwater “Great Wall” sensor network for real-time monitoring.

• Russia:

  • Poseidon nuclear-powered UUV, capable of carrying 2-megaton warheads, tested in 2024.

  • Klavesin-1R AUV for deep-sea ISR, deployed in Arctic waters.

• Europe:

  • Norway and UK lead with HUGIN and REMUS AUVs for MCM and oceanography.

  • EU’s Ocean2020 program funds networked UUVs for maritime security.

• Other Players:

  • Japan: OZZ-5 AUV for seabed mapping and ASW.

  • Australia: Ghost Shark XLUUV under AUKUS for Indo-Pacific operations.

India’s Initiatives in Underwater Drones and Surveillance

India is advancing UUV capabilities through the Defence Research and Development Organisation (DRDO), Indian Navy, and private sector partnerships, aligning with maritime security needs in the IOR:

• Key Projects:

  • AUV-150: DRDO’s autonomous vehicle for oceanographic research and surveillance, tested at 1,500m depth in 2024.

  • Samudra Kantha: Naval AUV for ASW and MCM, with AI-driven sonar, slated for 2026 induction.

  • Underwater Swarm Drones: DRDO’s 2025 trials of 10-drone swarms for coordinated ISR in the Arabian Sea.

  • Sea Guardian: India’s lease of US MQ-9B Sea Guardian drones (2023) includes underwater surveillance modules.

• Developments in 2025:

  • Successful tests of AUV-150 with indigenous sonar for submarine detection.

  • BEL-developed acoustic communication systems for real-time UUV data transfer.

  • Private sector (L&T, Tata) collaboration for modular UUV payloads.

• Strategic Role:

  • Counter China’s submarine deployments in the IOR and South China Sea.

  • Protect India’s 7,500 km coastline and EEZ from Pakistan’s drone-based incursions.

  • Secure trade routes through Malacca Strait and counter piracy/smuggling.

• Challenges:

  • Limited battery life and underwater communication bandwidth.

  • High costs: ₹5,000 crore allocated for UUV R&D (2023–2028).

  • Dependence on foreign sensors and propulsion systems.

• Opportunities:

  • Leverage India’s IT expertise for AI-driven UUV autonomy.

  • Collaborate with QUAD (US, Japan, Australia) for technology transfers under AUKUS-like frameworks.

Challenges in Underwater Drones and Surveillance

• Technical Challenges:

  • Limited endurance due to battery constraints (6–24 hours for most AUVs).

  • Acoustic communication delays (kilobits/second vs. gigabits in terrestrial systems).

  • Navigation in GPS-denied environments requires advanced inertial systems.

• Operational Challenges:

  • Harsh underwater conditions (pressure, corrosion) demand robust materials.

  • Vulnerability to acoustic jamming or cyberattacks on AI systems.

• Environmental Concerns:

  • Noise pollution from UUVs may disrupt marine ecosystems.

  • Risk of abandoned drones becoming ocean debris.

• Geopolitical Issues:

  • Proliferation to non-state actors (e.g., terrorist groups) could threaten maritime security.

  • Territorial disputes over UUV operations in contested waters (e.g., South China Sea).

Ethical and Regulatory Issues

• Ethical Concerns:

  • Autonomous Lethal Actions: Fully autonomous UUVs with strike capabilities raise accountability issues for unintended casualties.

  • Privacy Violations: Surveillance in international waters may infringe on sovereign rights or civilian privacy.

  • Environmental Impact: Prolonged UUV operations could harm marine biodiversity, necessitating ethical guidelines.

• Regulatory Frameworks:

  • International: No specific treaties govern UUVs. UN Convention on the Law of the Sea (UNCLOS) provides limited guidance on underwater operations.

  • India: Governed by Naval Integrated Command and DRDO’s Technology Perspective and Capability Roadmap (TPCR). Guidelines emphasize human oversight for lethal UUVs.

  • Challenges: Lack of global standards for UUV deployment; need for agreements on autonomous maritime weapons.

Future Outlook

• Short-Term (5–10 Years):

  • Semi-autonomous UUVs dominate, with India deploying Samudra Kantha for ASW by 2027.

  • Advances in battery technology (e.g., lithium-sulfur) extend mission durations.

• Long-Term (10–15 Years):

  • Fully autonomous UUV swarms integrated with quantum communication for real-time coordination.

  • Hybrid UUV-USV networks for multi-domain maritime operations.

• Strategic Implications:

  • UUVs will redefine naval warfare, enhancing ISR and ASW capabilities.

  • India must prioritize indigenous R&D to reduce reliance on foreign technology.

Underwater drones and surveillance systems are revolutionizing maritime defence, offering India tools to secure its vast coastline, counter submarine threats, and protect trade routes. As of August 2025, India’s advancements, like AUV-150 and Samudra Kantha, align with global leaders, but challenges in battery life, communication, and ethics persist. For UPSC aspirants, this topic underscores the intersection of technology, security, and geopolitics, requiring policies that balance innovation with responsible governance to ensure India’s maritime dominance.