Hi everyone, I hope it’s okay to post here even though I’m not using Blue Robotics products — I figured this community would have the most relevant expertise for my situation.
I’m a university engineering student working on a capstone project: a robot designed to traverse mudflat terrain (tidal flat environments with soft, waterlogged mud). Here are the details:
-
Motor: ROBOTIS XM430 series servo motor
-
Drive system: Sprocket + timing belt power transmission
-
Environment: Mudflat surface — not fully submerged, but continuously exposed to mud, water splashing, and high moisture
The XM430 is not rated for submersion, and I’m struggling to figure out the best approach to protect it. Specifically, I’m uncertain about:
-
How to seal the rotating shaft where the sprocket connects (lip seal, O-ring, or other?)
-
Whether to enclose the motor in a sealed housing, apply conformal coating, or use another method
-
What IP rating I should realistically be targeting for this kind of environment
Any advice from those with experience in wet/harsh environment motor sealing would be hugely appreciated. Thank you for your time!
Hi @2silver_q -
waterproofing an existing servo motor seems extremely challenging! Blue Robotics is on track to launch a subsea, pressure rated servo, that takes a somewhat similar approach to Blue Trails Engineering’s current offerings - encapsulate an existing servo “guts”. This is because modifying an injection molded part to have the necessary seals isn’t really practical, especially for more than a prototype!
In answer to your questions:
- A shaft seal is the typical o-ring type used to seal a rotating shaft. Checkout the parker o-ring manual as a design reference!
- It’s best to enclose the motor and gear train in a dry space - while flooding it would help with cooling and lubrication, the motors are typically brushed and use position feedback - both of these won’t work when wet. Additionally, solid particles of mud could really gum up your gears!
- IP69 rating (or Ingress Protection 69) is the highest standard for device durability against dust and intense liquid washdowns. It certifies that an enclosure is completely dust-tight and can withstand close-range, high-pressure (80–100 bar), and high-temperature (up to 80°C) water jets. Blue Robotics enclosures aren’t formally rated to this spec, but are subsea rated to the extreme pressures specified on each product page’s technical details section.
Thank you so much for the detailed response — this is incredibly helpful! The advice on keeping the motor in a dry enclosure and using a shaft O-ring seal gives me a clear direction to move forward with.
I’ll make sure to check out the Parker O-ring manual for the sealing design. Once I’ve completed the build and tested it in the field, I’ll come back and share the results here. Hopefully it can be useful for others working on similar projects!