DRDO’s Advanced Viscoelastic Isolation Mounts: Missiles, fighter jets and sonar systems usually dominate conversations about defence technology. But sometimes, one of the most important technologies on a modern warship is something most people would barely notice: a specially engineered mount placed underneath a machine.
The technology has recently drawn attention after reports that DRDO’s Naval Physical and Oceanographic Laboratory (NPOL) sought advanced NAVEM-A Mk1 viscoelastic isolation mounts for naval applications. The reported specifications are striking: the mounts are designed to support machinery weighing up to 2,000 kg, with a natural resonance frequency below 15 Hz and vibration isolation beginning at around 21 Hz.
What Is DRDO’s Advanced Viscoelastic Isolation Mounts?
Think about a washing machine during a high-speed spin cycle. Without proper supports, its vibrations can travel into the floor and walls. Now imagine that same problem on a naval warship except the machine may be a powerful diesel generator, pump, compressor or another piece of heavy equipment. The vibrations can travel through the ship’s structure and eventually into the surrounding seawater.
A viscoelastic isolation mount is designed to sit between the vibrating machinery and the ship’s structure. Its job is to reduce the amount of vibration and mechanical energy transmitted from one to the other.
The word viscoelastic describes a material that behaves partly like an elastic solid and partly like a viscous material. The elastic behaviour allows the mount to deform and recover. The viscous behaviour helps dissipate some vibration energy as heat.
Together, these properties allow the mount to act as a carefully engineered vibration filter rather than simply a piece of rubber under a machine.
How Does The Technology Work?
Every machine produces vibrations at certain frequencies. A properly designed isolation mount attempts to prevent those vibrations from efficiently travelling into the supporting structure.
The mount has to balance several competing requirements. It must be:
- Strong enough to carry extremely heavy equipment.
- Flexible enough to reduce vibration transmission.
- Durable enough to survive years of marine use.
- Resistant to temperature changes, mechanical loads and corrosion.
- Built to work well at the vibration frequencies the machines create.
A new line of work linked to DRDO-NPOL has looked at low frequency anti vibration mounts. In one test, researchers used nitrile rubber with short carbon fibers. They showed that changing the material mix can help cut vibration for marine platforms.
Why The 15 Hz and 21 Hz Figures Are Not Just Numbers?
The NAVEM-A Mk1 requirement puts weight on two values. First is a natural resonance frequency that should stay under 15 Hz. Second is the start of isolation near 21 Hz.
To keep it simple, each vibration isolation setup has a natural frequency. If the mount is not set up right, some vibrations can get stronger around the resonance point. So the mount needs to carry heavy equipment and still limit how much operating vibration passes through once it is past the isolation range.
DRDO’s 2024 Technology Focus publication also described Rubber Anti-Vibration Mounts (RAVMs) developed by NPOL. According to the publication, the mounts were developed for onboard machinery and equipment, with reported vibration damping of up to 60 dB, while some versions had been evaluated or accepted for naval applications.
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Why DRDO Is Investing In A Technology Most People Have Never Heard Of?
1. People often focus on radar and stealth.
But in water, sound control matters a lot too. If an enemy cannot detect your noise well, you can sail and maneuver with less trouble.
Inside a hull, parts can be hidden. Yet motion and vibration can still leak clues. Those small shake patterns can be noticed. So, cutting that noise makes the ship harder to track and harder to label.
2. Engines and drivetrains need extra shielding. Isolation mounts do more than just reduce noise. They also limit how vibration travels into the frame. That helps protect key parts are:
- Electronics that need stable conditions
- Sensors
- Sonar systems
- Other careful instruments
3. DRDO and the wider government effort have worked on making defence research and production more local. For FY 2026 to 2027, DRDO’s budget rose to ₹29,100.25 crore. Policy also asks for more help from industry, start ups and colleges for defence R and D.
4. Acoustic research is getting more attention now. NPOL works on sonar and related topics. Its work includes engineering systems, materials and ocean based technologies.
India is also expanding support for naval research. In April 2026, the government set the foundation for a Large Cavitation Tunnel at DRDO’s Naval Science and Technological Laboratory. The goal is to boost local research and testing.
These investments show that underwater technology is not limited to one weapon or platform. It involves a wider ecosystem of materials, acoustics, sensors, propulsion and structural engineering.
What Could These Mounts Be Used For?
While specific deployment details are not publicly available, heavy-duty isolation mounts of this type could potentially support machinery such as:
- Diesel generators
- Pumps
- Compressors
- Cooling and auxiliary systems
- Other vibration-producing naval equipment
The key point is that these systems may need to operate reliably without turning the surrounding ship structure into a pathway for mechanical noise.
