Quick hexTronik DT700 Brushless Outrunner 700kv motor test

[sthone]

motor2.jpg (130.29 KiB) Viewed 6754 times

motor2-2.jpg (125.16 KiB) Viewed 6754 times

While I was testing out the BlueRobotics T100 and my Magnettice drive thruster today I though I'd quickly test this motor also hexTronik DT700 Brushless Outrunner 700kv motors I bought this awhile ago because it already had a 4mm shaft so it fits most of the props I already have.

With a 3 blade 50mm Robbe prop it put out a max of just about 5 lbs of thrust. I'm not sure of the amps at thrust because my meter is a POS, but at 3.5 lbs it was drawing around 11 amps.

I also tried it with a 60mm prop but that only put out 4.5 Lbs at a staggering 18 amps.

Running it straight in the water would probably make it disposable after a while, maybe with a little epoxy coating it might last longer but overall for a quick cheap $13 thruster the results were not to bad.

-Steve

[a_shorething]

damn! You guys are testing stuff with crazy high amounts of force these days. (and power draw). I don't think I'd want or need to carry enough batteries to run two or four thrusters at 5+amps.


Steve, did you ever test the bilge pump motor thrusters that you have on your current ROV? That was sufficient power to do what you needed, right?

[sthone]

The most thrust I get out of the bilge pumps is around 2lbs (less after the voltage drop) but for normal use I find it plenty. (Keep in mind you'll hardly ever use full throttle either with a 6+ lbs of thrust)

My goal for any thruster I ever tried to do was 4lbs, which is why I was excited when I got that with the Bluerobotics thruster at a reasonable amp draw.

I think at this point I'm pretty much done trying to reinvent the wheel, I mean I still have thruster things I want to do just to see if I can do them but as far as thrusters go a simple exposed brushless setup works good enough for me. I might even build another Rov around the Bluerobotics thrusters but to go that route I would have to learn a lot more about programing to come up with control system.

-Steve

[a_shorething]

The most thrust I get out of the bilge pumps is around 2lbs (less after the voltage drop) but for normal use I find it plenty. (Keep in mind you'll hardly ever use full throttle either with a 6+ lbs of thrust)

My goal for any thruster I ever tried to do was 4lbs, which is why I was excited when I got that with the Bluerobotics thruster at a reasonable amp draw.

I think at this point I'm pretty much done trying to reinvent the wheel, I mean I still have thruster things I want to do just to see if I can do them but as far as thrusters go a simple exposed brushless setup works good enough for me. I might even build another Rov around the Bluerobotics thrusters but to go that route I would have to learn a lot more about programing to come up with control system.

-Steve

Thanks Steve, that helps a lot. I'm still making progress on my mag coupled thrusters and I plan to continue until I either come up against a wall or someone else does one that's affordable. For me, the idea of exposing an electric coil to the open water just seems wrong and no matter how many times someone tells me that it's OK it just won't feel right. It goes against everything I ever learned about electronics and electricity.

If you're interested in doing some stuff together, programming is my thing. I've got an interface that works on a laptop right now (using Xbox controller). It's working over Ethernet to a NetDuino but I'm playing with some other stuff as well, including serial comm to arduino Uno (previous iteration of the same interface) and some HUD stuff when I get that far.

I can help you with programming the way you've helped us all with your experience and by providing this forum.

Let me know.

[sthone]

I might just have to take you up on the programing help (eventually) I have a Arduino Diecimila Board that I was trying to run using a program I started in Visual Basic Express. I made some progress moving some servos and things but I got side tracked and probably forgot more than I ever knew at this point so I have to start over. I want to start a new Rov this year and if I do I want to get the control system done before I even think about building the actual Rov. I though of buying a ready made system but I kind of like the parts where I have to figure everything out myself. Designing things is more of the fun end of stuff to me. I use to have plenty of time for this stuff and limited budget, now I have the budget but limited time, and time is the one thing budget can't buy.

-Steve

[a_shorething]

I might just have to take you up on the programing help (eventually) I have a Arduino Diecimila Board that I was trying to run using a program I started in Visual Basic Express. I made some progress moving some servos and things but I got side tracked and probably forgot more than I ever knew at this point so I have to start over. I want to start a new Rov this year and if I do I want to get the control system done before I even think about building the actual Rov. I though of buying a ready made system but I kind of like the parts where I have to figure everything out myself. Designing things is more of the fun end of stuff to me. I use to have plenty of time for this stuff and limited budget, now I have the budget but limited time, and time is the one thing budget can't buy.

-Steve

Steve,

No problem, drop me an e-mail or PM or something and we can work together.

This little haven for hackers and tinkerers is a great little incubator for ideas and support (and criticism when it's warranted). This is like my favorite car forum: Feels like there are people hanging out in my garage waiting to talk about stuff I'm interested in.

There's no way I'd be as far along as I am without you and this forum and whatever I can do to return the favor is my pleasure.

I'm pretty good with the arduino stuff, OK with the hardware stuff, and really good at the PC-based programming (if I do say so myself ).

So far my research has led me through serial comm (PC to Arduino via USB) which could also be scaled to the RS485 I'm pretty sure to my eventual goal of Ethernet comm (using UDP but TCP/IP is a small step if that's what you're into, it's just more comm traffic and more secure). I've experimented with the Raspberry Pi and plan to use that for a webcam and currently my control of choice is the NetDuino that I plan to augment with an I2C bus in the ROV.

Let me know