We have tested the actuators to the equivalent of 10 meters depth for short periods (<30 minutes), but we cannot guarantee the actuator running continuously in a submerged without additional protections, like keeping the actuators at sufficient positive internal pressure. Each actuator has an internal pressure sensor that gets reported in the actuator feedback, making it possible to be sure of the integrity of the actuator seals while running.
Thanks for the question.
The easiest option would be to use the unused cord grip in the actuator and directly pass your air in thru there like in this image: except just directly connect your valve to the tube, no need for the t-junction. I have inserts for the cord grips that I can give you to fit (I believe) 1/4" tubing. Just send me an email (Willig@hebirobotics.com)
Then you will need to use 1.5mm OD SOLID CORE WIRE (like these: https://www.digikey.com/en/products/det ... 05/2195459 | https://www.digikey.com/en/products/det ... 05/2195471) into the other cord grip and you don't need to worry about the "pressurization adapter" shown on the docs website.
The reason you'll need to use the solid core wire is that the standard stranded wire we sell with the R-Series actuators allows a enough air to leak through it when the cord grip is closed such that actuators that are daisy chained together will, over time, evenly distribute their internal air pressure.
In the situation where, you have a chain of actuators that you want to pressurize all of them, use the standard electrical wire we supply between the actuators and then use the solid core wire coming out of your first actuator to prevent leaking. Then you can use the open port at your end-effector actuator to pressurize the system (like in the image below): *** NOTE: The internal pressure sensor on the R-Series actuator has the following stats - Most of this is found here for future reference: https://docs.hebi.us/hardware.html#r-series-sealing