Selecting gimbal motors
  • Hi,

    I'm new to this forum.
    So I'm trying to build a MoVI-like device. It's only going to be for handheld. But I'd like it to be able to handle heavy cameras such as the Epic or 5DMk3, etc. I just saw Alex's 3-axis prototype on youtube, very impressive.
    So my questions regarding the motors are:
    1. What off-the-shelf gimbal motor is best suited for this? Obviously the more turns of the wire is going to give me more torque, but what about noise? Which one is the most quiet? I've seen some powerful motors on youtube, but some are also quite noisy.
    2. Do I need 3 different motors or can I use 3 of the same motor for pitch/roll/yaw?

  • 5010 rctimer motors seem to be doing the job with a 5D, just had a few tests and it worked. For the epic i think we would need another board but not sure.....
  • Working on something much like this myself. What exact motor is Alex using in that new video showing 3 axis? tks in advance.
  • Fuwu, thanks for the info!
    johngore: I haven't built anything yet, still searching for various parts.
    Re Alex's motors

    Alex Moskalenko 3 weeks ago
    ROLL - DT750 (custom rewound), PITH - iflightrc 4008, YAW - biggest of turnigy multistar (custom rewound). But it is just prototype for my tests, don't use ROLL motor this way, but add second support.
  • Tks Jimmys. So will Gimbal Brushless Motor 5010 work for all axis then as well, or is this too weak / some other problem?
  • Some test with a 5D and 105 mm zoom lens:
  • jimmys On this gimbal I used the 5208´s...and they handle the RED for handheld no problem...

  • kikojiu, i have 5208 180t sealed motors, never checked with RED, here is my question, will the motors over heated for longer run time ?
  • Would 3x RCTimer 5010's on a handheld rig do the job for a Canon 60D with a 24-105mm lens, when correctly balanced? This configuration weights roughly around 1,5 kg. Or are the GBM5208's a better option for me?

    Where does 5010, 5208 etc stands for anyhow? Or are those just product numbers?

    @Fuwu, I just saw your video, I am assuming you are using the 5010's? No problems so far?
  • the 24-105mm shifts weight a lot when zoomed, especially if filters are used. GB85 is well enough for Canon 5D and 24-105, so maybe 5010 can take it at least in limited zoom range.
  • this is great info guys. I have been straggling to get gimbal for GH1 with a heavy lens (together around 900g) working properly and I thought my 5010 motors were not powerful enough. Now I know the problem is in the numbers not in the hardware. Back to tweaking PIDs...
    @OnlyNK as far as I know the numbers are made up by the manufacturers and not mean much. 5208 is supposed to be much stronger than 5010 and I was going to replace my 5010 with them.
    I have been tweaking numbers for 2 weeks now bot with 2.4 and 2.3 firmware. I got better results using 2.3 but I have to be gentle with the gimbal to get reasonable results. Any bump and I get jitters and rolling shutter issues on pitch.
  • do you use 3s or 4s batteries with 5010? does it matter?
  • You get more power with 4s, unless the motors get too hot already with 3s. Overall, for handheld use, I would recommend getting big motors, It makes things much easier and reliable. It is not only the power, but big motors have often better bearings too.
  • jhonalovej the 5208 will work with the RED depending on the accessories (weight). I mounted a RED on a gimbal with those motors it worked fine but it´s crossing the threshold. If you intend to fly on RED (multicopter) or use it heavily handheld go for stronger motors. You won´t be disappointed. 5208 or any other motor this size can´t be used with 3s...not enough voltage. Always use 4S. You´ll have power when you need it.
  • After a lot of tweaking I found that I have to set power to around 70-80 in the GUI to get the best footage. Will switching to 4s change anything in that case? If I use more power the gimbal is much more stable when stationary but I get lots of jitters once on the move. ALso with higher power I have to use very low values of D otherwise the motors start to vibrate.
    is 5010 considered a big motor and requires 4s? Will 4s change the threshold when motors start to vibrate?
  • pOlas once you increase the D you have to increase the P and vice -versa. It is always a 2 way compromise...One follows the other. Setting up one alters the other.
  • If you are running 70-80 with 3S I do not think there will be any improvements going to 4S.
  • @kikojiu. thanks. didn't know about that. My motors buzz/vibrate with any combination of P/D if I go up. especially with higher power. I took a scientific approach and just tried lots of combinations keeping track of them in a big spreadsheet. I'm still tweaking but I think I'm at the point that I'm happy with the footage. I have to be quite gentle though - any bumps result in some vibrations.
    @Garug thank you for clarification. That's what I thought but being inexperienced I wanted to make sure that I'm not missing something important.

    One thing that is really weird/annoying that I can get perfect PID settings with USB cable plugged in and the moment I disconnect it my motors start to vibrate. Like they need that additional power from USB - that's why I thought about going to 4s batteries. Anyone experience something similar?
  • I am using the bluetooth connection. Works great. But maybe as related to the 'USB cleaning the power'

    I have been thinking about the power subtly to the board and will be experimenting adding capacitors near the board. I have long wires between the battery and board and lot of audible non sequential noise from the motors, I think capacitors near the board might help. And maybe additional capacitors on the board. I will report back after experimenting.
  • pOlas if they vibrate lower the power. Sometimes vibrating without the cable connect means that the really light weight of the cable avoids the gimbal to resonate. When you have motor vibration resonates throught the gimbal and actually feeds back to the IMU. When the motor power is on the limit that happens. Also sometimes the tuning when on the stand it is very different for example when you are holding it handheld....
  • For those that are considering getting bigger motors, I got this from Neil Whiteley who already did:

    >>Little tip for you. DON'T use GBM8028-90T motors. These motors have amazing torque and look sick but they have substantial cogging. They are unsmooth especially on small slow movements. Stick with 8017-90T or maybe even another 42 pole motor from T motor or other manufacturer. I have two 8017-90Ts in the mail and Ill be replacing the 8028s.

    To save you the hassle if they don't work well for you either.

    http://www.iflight-rc.com/product/iPower-Brushless-Motor-iPower GBM-Motor-iPower-GBM8028-90T.html

    I think he meant 8017-120T

  • Would be useful the hear more about the GBM8028-90T, What does the substantial cogging mean, how does it show on video, would be good to see some video.

    I am currently using GB85 on the frame under development, it is really demanding for a solid frame.

    I am not totally convinced that huge number of poles is the solution for a smooth operating gimbal. Maybe it sets very high demand for the manufacturing accuracy. I am mostly happy with the GB85, but not totally happy yet. It is difficult to know if the issues are due motors, parameters, board/Sw, or frame, or maybe just how the camera/IMU is installed. Testing goes on, here is my current report:

  • Can someone else point out any tough on those big motor ?
    i woud prefer if they were closed but not if it is twice the price for the same result!

    From what i have understand
    the more turn the more torque.
    more pole equal more presision
    But 10 omh vs 15 ohm !???

    On the smaller side did someone tried those
    they look like 5208 closed but super cheap
  • you get what you pay for! do not complain when cheep crap fall apart.
  • Ok but what about the Ohm !!!???
  • Indon't go by Ohm but by tuns on the motor, more turns the more tork mor powet to lift , as you can see Ipower and tiger have the best GB motorsnon the market.
  • Turns alone do not tell much, unless comparing two otherwise similar motors. More turns mean more ohms, if everything else is same. More turns and Ohms may require more voltage to archive the full power (i.e. 4S might not be enough).

    Number of poles is a factor too, more poles provide more torque (if the poles compared are otherwise similar) larger can diameter provides also more torque.

    If looking only one parameter I would look the torque at the given voltage, but unfortunately this is rarely available.
  • exactly! so go by turns and poles most turns with most poles best motor Tiger GB85 top the list
  • Yes, GB85 is nice, I have it on all 3 axis ;-)

    With GB85 you get what you pay for and it is not only the torque, but excellent bearings, construction and quality.
  • Gb85 seam to ne priced a bit high but
    If it is good quality for à closed motor than it is where i will go.
  • Guys currently which is the best brushless motor in the market? I am cracking my head on how to reduce cogging and how to modify the motors. Any ideas?
  • I do not think there is simply one best motor. More information of your setup and problem would be needed.
  • Hey, guys!

    Do you think that a 4114 motor with 3 S lipo can manage a weight of minimum 700 g (usually this) and maximum 1,5 kg (rarely, only DSLR) with enough torque?

    I have RCTimer GBM4114 017-100T in my 3-axis gimbal and I'm suffering of some roll vibrations/fast oscillations I'm still trying to solve. I wonder if it needs more torque or it's something else.

  • what gimbal frame would the 8017 t120 fit on
    i have the 32 bit alexmos and motors but dont knowwhat frame to buy.....please help
  • I think the best for you is to buy some parts ( cages, tubes and connectors ) to build yourself your gimbal, because it's 4 days that i search on websites and i never saw a complete Gimbal without motors for 8017 motors size.
    You can find many parts here: http://mymobilemms.com/OFFTHEGRIDWATER.CA/index.php?main_page=advanced_search_result&search_in_description=1&keyword=cage&inc_subcat=0&sort=0&page=1