Using T100 or T200 Thrusters in MATE Competition


My team has been very impressed with your site and the possibilities your thrusters represent. We were very happy to see that MATE was specifically mentioned on your site. Our intention is to use the T100 and T200 Thrusters on our vehicle, however, MATE has thrown in a wrinkle we are hoping you will address.

From the competition manual: ELEC - 014N “Disposable motors” are not permitted; these are exposed motors with no waterproofing.

The MATE Forum post that addresses this is below:

This came out of a discussion by out MATE judge group about testing brushless motors. This is from a company that sells brushless motors, and if you are planning on using brushless motors you should make sure yours are up to this rigorous of quality control.

Quality Control

-Insulation Test, also known as a hipot test. We submerge the thruster in water and measure current leakage at high voltage (250V) to ensure that the insulation is sufficient.

-Spin Test. The thruster is operated in air across the entire speed range to ensure that it operates correctly.

-Visual Inspection. Each thruster is inspected for visual issues or damage.”

Hope this helps if you plan on using brushless motors.

Can you tell me how your thrusters are sealed and if they are waterproofed, and can you give assurances that they should meet and pass the inspection standards from MATE? The bulk of opinion seems to be that the motors need to be epoxy encapsulated, as stated in the quote below.

“If BlueRobotics are not epoxy encapsulated, then they have to be. The Turnigy motor that I referenced to above has to be epoxy encapsulated. The bearings need to be made completely out of stainless steel so as to not rust or replaced with non-rusting bushings. I am personally in the process of coming up with a process that will make the Turnigy motors agreeable for use in MATE competition based on other discussion threads from last year.”

We really want to use your thrusters so, please, can you shed some light on your processes for us. Thank you very much.

Michael McElrath - Mentor - Friday Harbor Robotics ROV Team


I would appreciate any response but I took a closer look at the product info for the Thrusters and realize that this probably covers it:

“The T100 is made of high-strength, UV resistant polycarbonate injection molded plastic. The core of the motor is sealed and protected with an epoxy coating and it uses high-performance plastic bearings in place of steel bearings that rust in saltwater. Everything that isn’t plastic is either aluminum or high-quality stainless steel that doesn’t corrode.”

We are looking forward to using your thrusters. We plan to use 4 T100 and 2 T200 Thrusters. My kids are in the fund raising/donation mode, atm and we’ll order them as soon as they have that wrapped up. Thank you, again.

Michael McElrath - Mentor - Friday Harbor Robotics ROV Team

Hi Michael,

I actually just responded to your post on the MATE forum but I’ll copy that here for reference.

We had some detailed discussions with MATE folks about this last year. Matt Gardner’s post on the MATE forum about the insulation requirements for brushless motors is based on that conversation and our motors meet those requirements. The motor windings are encapsulated from the water and we do a high-potential (hipot) test of each one to make sure that there is no current leakage into the water. Note that the encapsulation is done with a clear compound so it’s not always obvious at a glance that they are protected.

The Blue Robotics thrusters are used by lots of MATE teams at this point and we’ve had nothing but good feedback.

Let me know if you have any other questions. We’re always happy to answer and help out.

Best regards,



Thank you for a prompt and well defined response! We’re very excited about the prospect of using BlueRobotics Thrusters. Now the real work begins!

Michael M