Design of a Bio-Inspired Miniature Submarine for Low-Cost Water Quality Monitoring
Authors: Quang Huy Vu, Quan Le, Manh Duong Phung
Organizations: Quang Huy Vu is with HUS High School for Gifted Students, VNU University of Science, Hanoi, 100000, Vietnam. · Quan Le is with Fulbright University Vietnam, Ho Chi Minh City, 700000, Vietnam. · Manh Duong Phung is with College of Engineering and Computer Science, VinUniversity, Hanoi, 100000, Vietnam.
Water quality monitoring is essential for protecting aquatic ecosystems and detecting environmental pollution. This paper presents the design and experimental validation of a bio-inspired miniature submarine for low-cost water quality monitoring. Inspired by the jet propulsion mechanism of squids, the proposed system employs pump-driven water jets for propulsion and steering, combined with a pump-based buoyancy control mechanism that enables both depth regulation and water sampling. The vehicle integrates low-cost, commercially available components including an ESP32 microcontroller, IMU, pressure sensor, GPS receiver, and LoRa communication module. The complete system can be constructed at a hardware cost of approximately $122.5, making it suitable for educational and environmental monitoring applications. Experimental validation was conducted through pool tests and field trials in a lake. During a 360 degrees rotation test, roll and pitch deviations remained within +/-2 degrees and +/-1.5 degrees, respectively, demonstrating stable attitude control. Steering experiments showed a heading step response with approximately 2 s rise time and 5 s settling time. Depth control experiments achieved a target depth of 2.5 m with steady-state error within +/-0.1 m. Field experiments further demonstrated reliable navigation and successful water sampling operations. The results confirm that the proposed platform provides a compact, stable, and cost-effective solution for small-scale aquatic environmental monitoring.
Figures & tables
Fig. 1 : Locomotion mechanism of a squid based on jet propulsion [ 18 ] .
Fig. 2 : Prototype of the squid-inspired miniature submarine with labeled main components
Fig. 3 : Electronic circuit diagram
Fig. 4 : Controller software initialization in the Arduino IDE serial monitor.
No.
Item
Spec
Qty
Unit Price (USD)
Amount (USD)
1
Body
Acrylic cylinder OD 100 mm, length 750 mm
1
8
8
2
Thruster
12V 9W
2
5
10
3
Steering
5V 1W
2
1
2
4
Battery
12V 6Ah 10A
1
15
15
5
DC-DC converter 5V
5V 3A
1
1.5
1.5
6
DC-DC converter 3.3V
3.3V 2A
1
1
1
TABLE I : Bill of materials (BOM) for the miniature submarine prototype
Fig. 5 : Experimental setup in a pool.
Fig. 6 : Attitude stability during a 3600 yaw turn.
Fig. 7 : Differential drive steering response.
Fig. 8 : GPS track of a water navigation session in a lake.
Fig. 9 : Longitudinal stability during depth transition.
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Indian Institute of Science Education and Research Bhopal, India