Prototype Underwater Servo (Discontinued)

We have designed a special waterproof servo capable of operating at depths exceeding 100 m. Use the servo to build an underwater robot arm, trigger a water or sediment sampler, or drop a clump weight after your vehicle has made it to the bottom of a deep lake. We are very excited to see how these servos are going to be used. Here are a few projects that already use this device:


The servo has a standard three-wire servo connector so it can be adapted for use in many different projects. It is compatible with OpenROV 2.7 through the auxiliary wires but will require modification to the controller board. More detailed instructions and integration documentation will be released soon.

Release schedule:



  • Simple mechanical parts and injection molded housing helps keep the unit low-cost
  • Utilizes the rugged and reliable Hitec HS-82 metal gear servo
  • Liquid compensation architecture allows the device to work at tremendous depths
  • Standard servo connector for easy integration with many products

Servo specifications:

  • Speed: .1 to .12 sec @ 60 deg.
  • Torque: 2.8 to 3.4
  • Size: ~50mm x 45mm x 20mm
  • Weight: ~34g 

Why is this in the experimental category?

This is our first stab at a waterproof servo.  So far we’ve done basic testing in the field (watch a video of our first test at Lake Tahoe here), as well as tests in our pressure vessel with both freshwater and seawater. Before starting out with this servo here’s a list of some things to be aware of:

  • Spline extender is not held concentric - some oil may leak out when spline is loaded
  • Bottom panel is weak near screw holes - may crack open if dropped
  • Currently doesn't have a ready-to-go mounting solution - you will need to figure out a way to attach it to your device for now
  • Wiring it to your OpenROV will require some modification to the control board and installation of software/firmware to control the servo
  • The servo, like all the things in the experimental section of the store is community supported through the forums and is intended for advanced users or developers.

Once an order is placed on our webstore, it will ship within 1-3 business days. 

Taxes: For international orders, please note that it is the responsibility of the customer to cover any import any duties and taxes. You can use this third party online duty calculator to determine what the cost of this fee will be prior to ordering. The harmonization code we apply to commercial invoices is as follows:

ROV's, parts and accessories: 9503000000

Batteries: 8507600000

Apparel (Shirts and Hats): 6109100004

Once an order has been shipped, please allow up to: 

1 Week for Domestic (US) orders to arrive. 

2 Weeks for International orders to arrive. Please note that every countries' customs offices process orders at a different pace. 

Once your shipping label has been printed in our warehouse, you will then receive an automatic email containing a tracking number, and an invoice that you can use for accounting purposes. For international orders a commercial invoice is affixed either physically, or electronically to the package for the customs agents to access.