In context
By early 2023, autonomous underwater vehicles (AUVs) had become essential for ocean observation, resource exploration, and seabed mapping, with growing military roles in target detection and mine countermeasures. Advances in sensors, 3D printing, and lightweighting made it feasible to shrink AUV displacement without sacrificing capability, pushing micro AUVs—smaller, lighter, cheaper, and suited to swarm operations—into the spotlight for both civilian and defense applications.
What was reported
This review, from the State Key Laboratory of Robotics at the Shenyang Institute of Automation, systematically examines micro AUV research. It clarifies definitions: micro AUVs typically weigh no more than 50 kgf in air, carry payloads up to 7 kg, and if axisymmetric, have a main body diameter under 200 mm. They are characterized by small size, low power (average under 100 W), and low cost—often $10,000–15,000, versus $250,000 for small AUVs and $1 million for mid-size models like REMUS 600.
The paper categorizes micro AUVs by structure into body-of-revolution, arrow-body, and multi-body types. It details systems fully compliant with sonobuoy A-size standards (length ≤914.4 mm, diameter ≤123.875 mm), such as REMUS M3V, ecoSUBμ 5, MK 39 Mod 2 EMATT, ALAUV, and SEAScout. These are designed for air-drop or torpedo-tube launch, with features like vector duct thrusters, post-propeller rudders, and buoyancy adjustment for communication. Others, including RIPTIDE μ AUV, NemoSens, and SandShark, have main bodies within A-size but with protruding appendages, offering extended endurance—RIPTIDE μ reaches 400 hours using aluminum-seawater batteries.
Key performance figures include ecoSUBμ 5's 500 m depth rating and 24 h endurance at 1 kn, and ALAUV's 350 km range at 1 kn with a 0.42 W total power draw. The review also notes structural trade-offs, such as post-propeller rudders providing greater turning moment due to increased flow velocity.
Why it mattered
This review provided a structured reference for designing and applying micro AUVs, highlighting their potential to expand AUV use in shallow-water observation, scientific teaching, and distributed sensing via multi-vehicle cooperation. For industrial automation, it underscored a trend toward smaller, cost-effective, and easily deployable robotic platforms that can operate in swarms, opening new possibilities for scalable underwater inspection and monitoring.
“Micro AUVs have the advantages of small size, fast speed, and high maneuverability, making them suitable for mass production and swarm operations.”
Source: 《机器人》期刊 (robot.sia.cn) · Published 2023-03-11 · “微小型自主水下机器人研究现状”