Homebuilt ROVs Forum

Rusty I'm blown away so far by the thrusters they exceeded my expectations so far. I got a little excited and rushed that post I actually meant to mention that I'm sure that is not the top performance of the thruster. I don't have it setup still but I'm far far done with my tests. I just check the battery though and I'm only getting 11 volts to start with and I have it feeding the speed controller with at least 10' of 14 gauge wire so I am sure you are correct that I am getting a lot of voltage drop. I just wanted to see what the thrust to amp ratio was, either way the 4lbs of thrust at less than 8 amps so far is phenomenal, I'm going to get my better battery this week and shorten the leads and try it again this thing deserves to hits it's full potential.

-Steve

Steve,

Great! Glad to hear that you like it. I'd love to hear about the rest of your testing. We have a few performance plots on our website, also attached here. It would be great to have some of the data points validated on a different test rig.

Best,

Rusty

Got mine a few days ago. 6 of them for my ROV. Just finished flashing ESC's and it worked like charm. I got the 20A ESC. Thought about it.. How the heck can i cool down 6 ESC's inside of a 110mm tubing with 4 5A batteries.. Well. Love the thrusters so far. Printing mountingbrackets for my ROV later this week

Ok, I ran some more test today and the lower thrust outputs I was getting last time was definitely all battery/meter related on my end. (I should have prepared better last time but I was excited to give these things a go.)

Today I tested the thruster with two different batteries. The first battery was the same battery I used last time, but fully charged. This battery was putting out 12.6 volts. The second battery was my tiny motorcycle battery (Shorai Lithium-Iron) which was putting out 13.3 volts.

At first I ran the test the same why as before with the first battery and was getting only 4.8 Lbs of thrust at 10 amps which is a slight increase from last time, but the results still didn't seem right after talking to Rusty so I decided to forget the meter all together and hook directly to the battery. When I did this I could tell the instant I hit the stick there was a huge difference. The thruster was now pushing 6.4 pounds of thrust. I then tried the 2nd battery (also wired directly) and the thruster was now pushing 7lbs of thrust.

I'm not sure why I'm losing so much through power running though the meter when I try to check the draw, but maybe I'm hooking it up wrong (electronics really isn't my strong point) or this meter is a POS.

Overall I can definitely say these thrusters live up to Bluerobotics thrust claims I can honestly say I would and will recommend these thrusters to anyone in a heart beat. I might just have to get my hands on a T200 next (when they are available of course.)

-Steve

So I bought a new meter and ran a few more test today on the T-100 and the results pretty much coincide with the charts Rusty posted.

Thrust vs Amps
1 Lbs @ .95 Amps (12.87 volts)
2 Lbs @ 2.17 Amps (12.70 volts)
3 Lbs @ 3.8 Amps (12.52 volts)
4 Lbs @ 6.1 Amps (12.26 volts)
5 Lbs @ 8.2 Amps (12.05 volts)
6 Lbs @ 13.2 Amps (11.68 volts)

Again these are great numbers, most of the time you with be running at limited throttle with an Rov anyway so even if you programed your controller to max out say at 4 lbs of thrust to limit your amp draw you would have plenty of thrust for most tasks and more than enough when you needed it. I said it before ....... I think these thrusters are going to be a real game changer in the home build Rov hobby. I really have to hand it to the guys over at Bluerobotics they have an awesome product here. I think my next Rov is going to be built around a set of these.

-Steve

Good numbers! But at what voltage?

Sorry.. I added the volt info.

-Steve

Steve - Very nice! It's great to see some confirmation of our numbers on a different test rig. Thanks for doing that.

-Rusty
Blue Robotics

Very Interesting (and impressive ) article on Woods Hole Oceanographic Institution testing the T100 to 3000m.

http://www.bluerobotics.com/pressure-te ... 00m-depth/

-Steve

We recently built a jig the same as this
https://www.youtube.com/watch?v=tTSXH0VC5_k
It seemed to give a result not effected by the circling water you get in a small tub or increase in thrust from the water being pushed against a wall.
Anyway, using a variable voltage 50A power supply we got 2100grams @ 14.7amps holding 12volts from a new T100