Mikrokopter Can Mikrokopter FlightCtrl run a 2 axis gimbal directly?

[JohnGore]

Hi

Still deciding which gimbal to buy (like MK HiLander SLR2 or Photohigher AV200).

I want to run the gimbal stablisation from outputs on the MK FlightCtrl that is already running the OctaXL (ie. so only 1 set of gyros runs stabilisation of the OctaXL and the Gimbal as well).

Is this possible?
Will the output voltage and amps be enough to run the servos on the gimbal (either MK HiLander SLR2 oe Photohigher AV200) ?

tks very much!

 

[BorisS]

HI John,

japp the MK FC can stabilize whatever 2 axis gimbal you choose. Concerning the amps that the servos need or even the voltage it is better to use a separate BEC. Once to be flexible on the voltage and the MK FC docent provide enough amps for most servos or lets say it like the the ones you find on the gimbals you mentioned before.

check for example the MK wiki http://www.mikrokopter.de/ucwiki/en/FlightCtrl_ME_2_1

connectioons diagram for roll and nick servo

Boris

 

[JohnGore]

HI John,

japp the MK FC can stabilize whatever 2 axis gimbal you choose. Concerning the amps that the servos need or even the voltage it is better to use a separate BEC. Once to be flexible on the voltage and the MK FC docent provide enough amps for most servos or lets say it like the the ones you find on the gimbals you mentioned before.

check for example the MK wiki http://www.mikrokopter.de/ucwiki/en/FlightCtrl_ME_2_1

connectioons diagram for roll and nick servo

Boris

Tks very much for the fast reply!

So I would need 1x 6v BEC for each of the servos? (2 BEC's in total). Should I then also carry 2 batteries, or just one on the gimbal (maybe 2 would be easier to wiring and weight balancing).

 

[BorisS]

NAh you need one bec that can provide enough A for both servos. I would recommend a little more in the pricey side but good quality:

http://www.castlecreations.com/products/ccbec.html

you will also need the CC USB link to program it.

Can give out up to 10 A more than you need and you can program in 1/10 th step for voltage output so you can really tune it to what works best.

Voltage intake from 2s to 6s.

http://www.castlecreations.com/support/documents/cc_bec_user_guide.pdf

Separate Lipo is good for a the gimbal but not a must.

 

[BorisS]

There are cheaper ones. But i already ruined stuff with the cheap ones to i stick to CC from now on. If you want a cheaper one look for a bed that can do 5v/6v output and up to 5A.

 

[JohnGore]

NAh you need one bec that can provide enough A for both servos. I would recommend a little more in the pricey side but good quality:

http://www.castlecreations.com/products/ccbec.html

you will also need the CC USB link to program it.

Can give out up to 10 A more than you need and you can program in 1/10 th step for voltage output so you can really tune it to what works best.

Voltage intake from 2s to 6s.

http://www.castlecreations.com/support/documents/cc_bec_user_guide.pdf

Separate Lipo is good for a the gimbal but not a must.

Great, but sadly they are out of stock...

Will this work? Can do both 5V/5A or 6V/5A ... http://www.hobbyking.com/hobbyking/store/__6320__TURNIGY_5_7_5A_8_42v_HV_UBEC_for_Lipoly.html
or this one (8A or more): http://www.hobbyking.com/hobbyking/store/__6233__TURNIGY_8_15A_UBEC_for_Lipoly.html

 

[RTRyder]

Great, but sadly they are out of stock...

Will this work? Can do both 5V/5A or 6V/5A ... http://www.hobbyking.com/hobbyking/store/__6320__TURNIGY_5_7_5A_8_42v_HV_UBEC_for_Lipoly.html
or this one (8A or more): http://www.hobbyking.com/hobbyking/store/__6233__TURNIGY_8_15A_UBEC_for_Lipoly.html

Any decently made BEC will work provided it has enough amperage to power the servos at maximum draw. The MK flight controller uses a Recomm on the servo power circuit that is rated at 1 to 1.5 amps maximum, most middle to high end digital servos are capable of drawing 2 to 3 times that at full power so anything larger than an MK Hisight II with small analog servos needs it's pown power supply. If you plan to use a gimbal with high power servos AND carry a heavy camera you want a BEC that is capable of providing at least 8 amps to have enough power to move both servos at the same time and a bit of a safety margin.

I use the CC BECs exclusively, on the smaller GoPro mounts I use their standard BEC, on my Cinestar with Photohigher AV130 I use the BEC Pro with dual outputs so each servo has its own power feed rather than having to make a Y harness to use with the single output standard BEC. If you do a Google search you can easily find someplace that has the CC BECs in stock, I highly recommend them.

Ken

 

[Bartman]

john,
you can make the whole thing very easy for yourself....put high voltage servos in that will run off of a 2 cell lipo pack and power the servos directly with only the signal coming (white wire in Futaba servo wires) from the flight control. That way you don't have to worry about a BEC crapping out and you can also put a switch in the wire so you can wait to power up the mount until after you've done the sensor calibration (your mount will thank you). The 2 cell lipo power is also good for powering other things that may be operating independent of the FC like a video transmitter. I've got a 2200 mah pack on my camera mount and it's good for at least ten flights.
Good luck with it.
Bart

 

[RTRyder]

john,
you can make the whole thing very easy for yourself....put high voltage servos in that will run off of a 2 cell lipo pack and power the servos directly with only the signal coming (white wire in Futaba servo wires) from the flight control. That way you don't have to worry about a BEC crapping out and you can also put a switch in the wire so you can wait to power up the mount until after you've done the sensor calibration (your mount will thank you). The 2 cell lipo power is also good for powering other things that may be operating independent of the FC like a video transmitter. I've got a 2200 mah pack on my camera mount and it's good for at least ten flights.
Good luck with it.
Bart

If you do that and have only the control signal coming from the F/C which is powered from a completely independent power source, you really should have a common ground between the two battery packs. There is no way for the servo to accurately reference the voltage level of the control signal unless both the servo and F/C have that common ground. You may get away without it for a while but don't be surprised if at some point the servos act funny or fail to respond to stabilization commands from the F/C.

On an MK it really doesn't matter if the servos have a switch or not, the control circuit doesn't become active until the gyro calibration is done (throttle to max and full left rudder). If you're finding this to be an issue it's likely to be because the common ground isn't there.

Ken

P.S. a switch in the power feed anywhere on a multirotor is more likely to fail than a BEC, vibration will kill a switch a lot quicker than the MTBF of solid state components.

 

[JohnGore]

Any decently made BEC will work provided it has enough amperage to power the servos at maximum draw. The MK flight controller uses a Recomm on the servo power circuit that is rated at 1 to 1.5 amps maximum, most middle to high end digital servos are capable of drawing 2 to 3 times that at full power so anything larger than an MK Hisight II with small analog servos needs it's pown power supply. If you plan to use a gimbal with high power servos AND carry a heavy camera you want a BEC that is capable of providing at least 8 amps to have enough power to move both servos at the same time and a bit of a safety margin.

I use the CC BECs exclusively, on the smaller GoPro mounts I use their standard BEC, on my Cinestar with Photohigher AV130 I use the BEC Pro with dual outputs so each servo has its own power feed rather than having to make a Y harness to use with the single output standard BEC. If you do a Google search you can easily find someplace that has the CC BECs in stock, I highly recommend them.

Ken

Thank you, this is very valuable info!

How do you find the cinestar gimbal vs the av200? I'm about to buy a gimbal, and serriously thinking of going for the cinestar, rather than av200, but is the difference noticeable? Tks

 

[Bartman]

If you do that and have only the control signal coming from the F/C which is powered from a completely independent power source, you really should have a common ground between the two battery packs. There is no way for the servo to accurately reference the voltage level of the control signal unless both the servo and F/C have that common ground. You may get away without it for a while but don't be surprised if at some point the servos act funny or fail to respond to stabilization commands from the F/C.

On an MK it really doesn't matter if the servos have a switch or not, the control circuit doesn't become active until the gyro calibration is done (throttle to max and full left rudder). If you're finding this to be an issue it's likely to be because the common ground isn't there.

Ken

P.S. a switch in the power feed anywhere on a multirotor is more likely to fail than a BEC, vibration will kill a switch a lot quicker than the MTBF of solid state components.

hi ken, how's everything been. i do have a common ground in the harness for the camera mount and you're right, the control signal doesn't activate until after the gyro calibration but the signal isn't always clean when it first activates and can cause the mount to spasm before going to it's presets. regarding the switch, the camera mount is the lowest vibration spot on the helicopter if i've done my job correctly and the switch is built into the mount. so far, so good, not too worried about it and boy is it convenient to not have to plug and unplug another battery connection after every flight.

fwiw, i don't think the servos will function without the common ground. my first harness when i was using A123 packs for the mounts was DOA until I added the ground to the signal line.

for anyone that wants to try it, the harness is pretty easy to make using two standard servo y harnesses. signal/ground to the flight control for each servo (clip the red or dark brown power wire), signal/power/ground to the servo, power/ground to the battery (clip the white or tan wire), combine the two power/ground leads from each Y harness to a common plug for the mount's battery. throw a switch in the red wire coming from the battery and you've got an independent, switchable power supply for your camera mount. any switch from an RC kit will work as they do on hundreds of thousands of RC planes/helicopters/cars that have ever been built.

bart