The short answer
Start from what the vehicle has to do, then check six things: voltage system, thrust in every direction you need, whether the ESC is external or built in, propeller rotation, depth rating, and mounting and cabling. For compact ROVs and student prototypes, Blu-Sub's Z60 family is the usual starting point, with the Z60E when a built-in ESC would simplify the wiring.
- The 12 V and 24 V versions use different motors and perform differently.
- Peak forward thrust alone is misleading. Size for forward, reverse and vertical control.
- Mix clockwise and counter-clockwise propellers so the reaction torques cancel.
How to choose an underwater thruster for an ROV.
Choose a thruster for the whole vehicle: thrust, voltage, rotation, depth rating, control electronics and mounting all depend on each other. Use this guide to write down a specification before you pick a Blu-Sub thruster.
Decide what the vehicle has to do first.
Inspection, research, intervention and student ROVs need different propulsion. Write down where the vehicle will work and what it will carry, then compare thrusters against that.
01 — VEHICLE
Vehicle size and mass
Estimate the dry mass, the buoyancy in water, the payload, and anything that adds drag, such as cameras, manipulators and tether-management hardware.
02 — MANOEUVRING
Thrust and layout
Decide whether the vehicle needs horizontal thrust, vertical heave, vectored thrust, or spare motors for redundancy.
03 — ENVIRONMENT
Depth and water conditions
Note the working depth, water temperature and salinity, and how likely the propellers are to meet weed, debris or sediment.
Six checks before you shortlist a thruster.
01
Voltage system
Match the thruster to the vehicle's power system. The 12V and 24V versions use different motors and perform differently.
02
Thrust requirement
Size the number and type of thrusters from the forward, reverse and vertical control you need. Peak thrust on its own will mislead you.
03
ESC arrangement
Decide whether an external ESC fits your electronics layout, or whether a thruster with the ESC built in would make the wiring simpler.
04
Rotation direction
On a vehicle with several thrusters, specify clockwise and counter-clockwise propellers so the reaction torques cancel and the layout works.
05
Depth rating
Check the pressure rating against the deepest the vehicle will go. A thruster that works in a test tank tells you nothing about depth.
06
Integration details
Check the mounting pattern, cable routing, penetrators, connectors and guard options against your frame and enclosure.
Which Blu-Thrust family to start from.
| Platform | Typical selection context | Configuration question |
|---|---|---|
| Blu-Thrust Z60 | Compact ROVs, diver-propulsion vehicles and student prototypes. | Does an external ESC suit your electronics layout? |
| Blu-Thrust Z60E | Compact vehicles where a built-in ESC saves wiring. | Would a built-in ESC help this vehicle? |
| Blu-Thrust Z80-170 | 24V ROVs, USVs and underwater robots that need more thrust. | Which propeller rotation and controller layout do you need? |
| Blu-Thrust Z80 / Z80E-290 | 12V vehicles that need high thrust. | External ESC or built-in ESC? |
Send us this and we can recommend a thruster faster.
- Vehicle type, use case and expected operating depth
- Required number of thrusters and preferred mounting layout
- Battery voltage, available current and controller preference
- Target thrust, or the vehicle mass and payload so we can work it out
- Quantity and the delivery location in India
Sources.
- Thrust, voltage, depth rating and ESC configuration figures for the Blu-Thrust Z60 and Z80 ranges, from the manufacturer's published specifications.
- Thrust figures are quoted at a stated voltage, and change with it.
Published 6 August 2026. Last revised 25 September 2026. Corrections to sales@vebixautomation.com.
Talk to us about your ROV thrusters.
Vebix Automation is an authorised Blu-Sub distributor. We can compare the options for your vehicle and quote for the quantity you need. Ask for a quote.
More on underwater robotics
- Underwater and ROV thrusters in IndiaBlu-Sub and Blue Robotics underwater thrusters for ROVs, AUVs and USVs, with prices in rupees and delivery across India included.
- How to size an underwater thruster for an ROVSize ROV thrusters from drag, target speed and vectoring angle. Worked method for thrust per unit, thruster count and the margin real vehicles need.
- Designing a 300-metre ROV propulsion systemPropulsion design for a 300-metre ROV: thruster count and layout, bus voltage, tether losses, sealing and the effect on buoyancy.
- Aluminium versus acrylic subsea enclosuresAluminium and cast acrylic subsea housings compared on depth rating, optical access, heat, servicing and cost.
- Selecting a subsea enclosure for marine research payloadsHow to choose a subsea enclosure, end caps, seals and penetrators for research payloads, and how to test them before fieldwork.
- Subsea pressure and depth conversion guideConvert depth to pressure in bar, psi, MPa and atmospheres. Reference table, the formula behind it, and how depth ratings and test pressures relate.
