Flow measurement does not always happen in calm or easily accessible water.
Survey teams may need to work during flood season, measure very shallow water, reach specific points accurately, or operate in areas where putting a crewed boat on the water is not practical.
The Alpha M4 hydrological USV is designed to support these kinds of field conditions. With an ADCP onboard, it combines autonomous vessel operation with real-time flow measurement in a compact, single-person system.
Here are 10 common questions about the setup.
The Alpha M4 can carry an ADCP (Acoustic Doppler Current Profiler) to measure flow velocity and direction across different water layers.
This makes the system suitable for a range of flow measurement applications, including low-flow and high-flow conditions, ecological flow monitoring, irrigation channels and reservoir gates.
Yes.
The M4 features a dedicated mounting platform that supports Alpha Surveying’s ADCP as well as mainstream ADCP models from other manufacturers.
The platform is not limited to ADCP applications. Depending on the survey task, it can also be configured with multibeam sonar, water-quality multiparameter sensors and automatic water samplers.
This gives users more flexibility to configure the same USV for different field applications.

No.
The system hardware is integrated and tested before delivery. After receiving the system, only simple installation is required before operation.
This helps reduce setup work in the field and allows the survey team to focus on the measurement itself.
No.
The Alpha M4 + ADCP can be operated using the boat's controls and a remote controller, without the need for an external computer or additional communication equipment.
During measurement, flow velocity profiles and flow direction are displayed dynamically in real time. Flow results can also be output directly, without requiring additional software for processing.


Yes.
The Alpha M4 integrates RTK positioning and heading functions.
Operators can plan a route for autonomous navigation or select a location directly on the map for automatic navigation.
The system supports:
This reduces manual steering during repetitive measurement tasks and helps improve field efficiency.
The Alpha M4 + ADCP supports an operating speed of up to 5 m/s, allowing it to operate in fast-flow conditions during flood season.
The ADCP used with the system has also passed product certification by China’s Ministry of Water Resources. Its technology is domestically developed and manufactured, and its flow measurement accuracy meets the requirements of the relevant acoustic Doppler flow measurement standard.
For survey teams working in changing water conditions, this provides a combination of mobility and measurement capability.
The M4 + ADCP is designed to cover a wide range of flow conditions.
It can measure both relatively fast and very slow flows, as well as work in deep and shallow water.
Its shallow-water measurement capability extends down to 20 cm.
This makes the system suitable for flow measurement across different water-level conditions, including reservoir surveys during high-water and low-water periods and ecological flow monitoring.
Working on moving water requires more than measurement accuracy. The vessel also needs to handle common field risks such as entanglement, obstacles and accidental contact.
The Alpha M4 incorporates several features for this purpose.
The pump-jet propulsion system is fully integrated into the hull and designed for strong anti-entanglement performance.
If entanglement occurs, the propulsion unit can be removed by hand for cleaning without searching for additional tools.
An HD camera provides a live view of the vessel and its surroundings, allowing the operator to monitor navigation conditions remotely.
A built-in millimeter-wave radar can detect obstacles and support automatic deceleration and intelligent obstacle avoidance.
The hull uses alloy bow armor and full-perimeter bumpers to provide additional protection against collisions, including impacts at higher operating speeds.
The M4 uses a modular battery design.
Users can configure the system with 1–3 batteries depending on the required operating time and portability.
The standard configuration includes two batteries and provides up to 7.5 hours of endurance.
This allows the same platform to be configured differently for shorter inspection tasks or longer field operations.
Yes.
The Alpha M4 is 115 cm long, allowing it to fit into the trunk of a typical passenger car.
The complete boat weighs 24 kg without batteries, making it possible for one person to transport and operate the system.


The Alpha M4 is not designed around just one sensor or one survey task.
Its ADCP configuration supports flow measurement across different water conditions, while its flexible equipment platform allows other payloads to be installed when the application requires them.
For survey teams, that means one compact USV can serve as a platform for different water-based operations — without having to start with a completely different vessel for every task.
Alpha M4. One platform. Multiple survey applications.