Subnero Water Assessment Network

Subnero Water Assessment Network (SWAN) consists of a team of low-cost, autonomous, robotic swans that can navigate autonomously, collect water samples at different locations, analyze them in the field and upload the results to a central server, where a user can monitor it from the comfort of his/her own office. Swans are usually associated with clean waters and go along well with recreational activities. A team of swans can do simultaneous spatial data sampling, over a period of time, in a cooperative and adaptive fashion making them perfect for obtaining statistical coverages. They need minimal logistical support as they return home automatically after their tasks are completed.


Clean and sustainable water sources are, without doubt, a basic requirement for any modern society. However, monitoring rivers, lakes, reservoirs etc. is not a trivial task. Some of the commonly employed methods are periodic manual sampling, continuous fixed sampling (e.g. fixed buoys) and sampling with Autonomous Underwater Vehicles (AUVs). Most of them lack the capability to generate dense datasets (both in time and space) which are required by researchers and managers of these facilities for effective monitoring. Also, they do not provide real-time, in-field data processing capability at a manageable cost.

The SWAN provides a scalable, autonomous platform for in-situ water quality measurements. Some of the key features of SWAN are:

  • Unattended, autonomous
  • Mobile, intelligent
  • Sample at places that matter
  • Persistent presence
  • Cloud-based
  • Real-time data
  • Interactive mission control
  • Minimal logistics
  • Low cost, simple & safe

Fully autonomous

A team of low-cost robotic swans navigate autonomously, take in-site water quality measurements, upload results to a central server, and when required, collect water samples. Users can monitor a fleet of swans from the comfort of their own offices.

Cloud enabled

A cloud-based system allows the operator to adapt missions quickly based on real-time data. Operators can access the user interface from a variety of platforms. This enables rapid software updates and improved scalability, thereby lowering operational costs.

Ease of integration

The SWAN supports industry standard water quality probes. Other sensors such as camera, echo sounder, etc can be easily integrated into the system, catering to a variety of applications such as water quality monitoring, surveillance and bathymetric mapping.

Comparison with other methods

  SWAN Manual Fixed buoy AUV
Automated n/a
Real-time data
Low maintenance
Low cost

Technical specifications

Feature Details
Communication interfaces SMS, 3G/4G, WiFi (802.11g 2.4 GHz)
Control & navigation Autonomous (GPS), 2.4 GHz radio
Software & user interface Cloud-based integrated management console
Endurance 8-12 hours (depending on mission)
Battery 270 Wh Li-polymer chemistry, rechargeable
Storage 128 GB
Supported sensors GPS, compass, camera, echo sounder
Supported water quality probes Eureka Mantas 2, YSI 6000
Dimensions (base, including thrusters) 70 × 40 × 40 cm
Weight (typical) 12 kg
Additional accessories Battery charger, storage stand