Thanks for the info bill, do you know how should I start with the power numbers for 8017 and 8102 motors? Thanks
Steve you were right, the new one (v2) has no i2c errors and seems to work fine. Tomorrow i will try. Thanks. jordi
I'm looking at picking up one of the Alexmos new 3-axis 32-bit basecam boards for use with GB 85 motors. http://flyduino.net/Alex-Mos-Brushless-Gimbal-BLG-32bit-Basecam_1 The board is said to supply 3A to each motor. Is that sufficient for the 85's or will I need the 70A high power board ? Thanks for your input!
Hey guys... I've got an issue with my new built 3axis direct driven gimbal. It's a mix, i used the 2 axis parts from the DYS eagle eye gimbal and for the pan i bought a pan motor cage with a dys bgm8108-90 motor in it. Roll and tilt are rock steady in flight, but i struggle with the pan. in my dry tests on the ground the pan works great, i can tilt the gimbal 40° and control it via the operators Tx without problems, but as soon as i go up in the air the pan starts cogging left and right, like it did before i got the "right" PID's on the ground. I have to wait for the bluetooth module, before i can do some quicker in-flight PID changes, now i have to land it and connect to the laptop, set new value etc... what really takes a lot of time, so maybe i simply havent' found the right values yet. The gimbal is balanced very good and not affected by vibrations from the MR, i've tested this several times. Now my question: Do you guys think the downwind of the MR motors could affect the landing legs in that way, that the yaw axis begins to struggle? I use a flat CS 8 with 450mm booms and 14" Tiger props. Could this be the problem or do i still haven't found the right PID values? Thanks for any help!
Urs: [EDIT: I thought you were using a MōVI, but then I realized you were not so edited this posting.] Can you confirm that, with the CS8 on the ground, and tipped up so that it's resting on two of the boom ends on the ground/table (in other words the booms are in a vertical plane), that you can rotate the EDIT MōVI the gimbal into any arbitrary angle and it will stay there? EDIT: My guess is that the pan motor is not receiving a high enough current to hold the mass of the gimbal and so the gimbal is overpowering it. The propwash may indeed be enough to buffet the gimbal beyond the holding power of the pan motor. Thanks Andy.
Dear Andy, i haven't tried it with the gimbal on the CS, only mounted to a speaker tripod. Yes i can confirm that, but it's not a Movi! it's something selfmade, as you can see in the pictures...? Regards, Urs
Urs: Sorry -- I edited my post when I realized it was not a MōVI -- so see the blue text of my posting. Andy.
Andy, yes i saw it right after i wrote.... Thanks for your thoughts. Do you think i haven't given enough power to it by the software or is the alexmos not able to get enough current to such big motors? I'm building right now a serial bluetooth module, so i hope i can do some inflight tuning tomorrow. Thanks again!
Hi Urs: I'm not really sure. I don't know much about Alexmos as it's not a Freefly-related product, I'm afraid. Andy.
I solved it, i simply had wrong PID's and Power. Could adjust it in-flight via bluetooth... Thanks anyway for your help! And to all: i really can recommend this gimbal. It costed me 600$ for the eagle eye handheld (with original basecam alexmos), 200$ for the pan cage and 180$ for the motor. Everything ordered from china.... All booms and the legs are the original freefly ones. So if you want a really cheap 3axis brushless gimbal, i recommend this mix! Thanks
Hello Urs Would you mind posting your before and after PID for the PAN when you were having the issues and what you corrected them to its a reference for others who may run into a similar issue?
EDIT as promised, here are the PID's i used for my gimbal: https://dl.dropboxusercontent.com/u/12574832/PID's.jpg First I only gave 155 Power to the pan motor. It works good with 190 now, the PID's are quite good. Here is a link to a footage video, i've cutted it because i was hovering the most of the time. No post-stab! The Pan works quite good, there are little jitters still there, but most of it what lookks like jitters in this video is because of the youtube compression. Still need some fine-tuning, but looks promising. i hope this values and video helps someone. Camera is the Sony a7r with the Sonnar T* Zeiss FE 24-70F4 Cheers
Good morning? Have a question. I just finish my gimbal with 2 8017, pan and rol and 2 iPower GBM5108-120T on tilt. MY question is: when 2 motors are used for tilt, do I have to double the amount of poles? Thanks
Nope, what you need is connect the two tilt motors in parallel, but with cables switched so that each motor turns in different direction (since they are going to be mirrored). What's really important is to align the two motors together so that their stators and magnets mirror each other. This can take a bit of trial and error. The motor pole count in the settings should be set to mimic only one motor. The controller acts as if there was only one motor.
Hi Reno, For now we shoot with the Sony a7R, but as soon as we get it, we're going to upgrade the gimbal for the BmPC4K