HOW TO : Differential Thrust | Flite Test
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- เผยแพร่เมื่อ 16 มิ.ย. 2024
- Josh goes over the basic setup for differential thrust. In this overview we use the Graupner MZ-12 but the information should help you with any 6 channel transmitter.
Learn more about the MZ-12 here:
store.flitetest.com/graupner-m...
Graupner MZ12 Product overview here:
• Graupner MZ-12 - Tutor...
Some of our DIY airplanes that can be setup with differential thrust:
FT Seaduck
• DIY Foam Board Water P...
FT Cruiser
• Flite Test - FT Cruise...
More R/C airplane kits available here:
store.flitetest.com/all-aircraft
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I recently programed my spectrum 6(black) for differential thrust, watching every video I could find. It took two full days. The roller is now hard to use due to wear. Result was a switch was activated in a menu 3 levels into the programing FROM THE FACTORY that prevented success . After all that work I found that flying two motors on one battery (2200 mha 35c) drew so much current (40 amps)that it swelled a battery with each flight. The plane I built was able to carry two batteries in parallel and cured the problem . You really have to want a twin! I wish josh would put a wattmeter on their recommended setup.
Keep up the great work with the videos. You guys got me into the hobby. One suggestion I think you guys should make a video on another day along with a video on Monday and Wednesday.
Love you guys and the show. without you guys I would probably be out of the hobby. building is what kept me in it
Really enjoy you info videos, I learn a lot from them. THANKS
Really nice tutorial. Keep up the great work guys.
this is awesome, I think if more videos were out there like this one, not so many people would stop a 4 channels
I am gong to describe a very interesting problem I had/have using HKing ESC's and a Turnigy reciever, that i think is worth sharing in case anyone else runs into it.
I set up differential thrust essentially the same way you did, but one or more of my motors would continue spinning even at zero throttle following rudder inputs. As long as I didn't enable the rudder mix, both motors would start and stop at the same time. If I enable rudder mixing and move the rudder back and forth a bit, many times one or more of the motors would continue spinning at low speed even though the rudder is moved neutral and the throttle moved all the way down. After doing some troubleshooting/meditating on the issue, I came up with a possible explanation.
Before you ask, I did all the obvious stuff, ESC calibration, small tweaks to trim and mix settings, and the like.
The total travel of the sticks on my radio is limited mechanically by the chassis of the transmitter itself. If I were to take off the front faceplate of my radio, my sticks would have a small amount of extra movement. At some level, the sticks themselves have to return to the computer in the radio a numerical value indicating their position. For my example, I will say that with the faceplate on, my radio delivers a numerical range of -95 to +95, and with the faceplate off, perhaps it delivers a maximum of -105 to +105.
When the sticks on the radio are calibrated, the radio knows that when the throttle reads back "-95" indicating the throttle is all the way down. The radio sends a "-100%" signal to the throttle channel, and the ESC's are calibrated to exactly this signal. What I think happens to cause my problem, is that when i'm at 25% throttle, and I throw the rudder hard to the left, the right ESC somehow gets sent a signal that is "lower" than -95. This somehow causes the ESC to think "oh no, I must have been miscalibrated before because I'm getting a new lowest possible reading on the throttle." The ESC seems to on-the-fly recalibrate itself to this new value for "zero throttle," thus when I move the stick all the way down, one or more of my motors continues to turn.
My workaround for this problem was to disable subtractive mixing all together. Rudder inputs only add signal, they never subtract it. Since making this change, my motors always stop when I kill the throttle. A more robust solution would probably be to install better firmware for my radio.
Great demo and good info. Thanks.
The amount of mixes required for this function can vary depending on your transmitter's programming capailities/functions. One very IMPORTANT thing to have when doing this sort of setup is to make sure you have a receiver that has the proper FAILSAFE functions for the secondary throttle as some receiver will simply HOLD LAST COMMAND which would be very bad with this setup in the event signal was lost.You would get the esc/motor on throttle channel go to low throttle position while the other secondary esc/motor would simply stay running at what ever RPM/throttle you had it moments before losing signal...
You should make a compilation of your crashes :D great job as always
Thanks so much, this video was so helpful!
this is very helpful, and like you said works on most tx,s as I am using turnigy 9xr and 9xr pro would you say this is possible with these tx,s or not if I wanted to use this idea???
Watching videos, 737-800 NGX, I've seen the engine throttles at slightly off positions of each other to off set what I believe to be two problems of flight. One being to off set cross winds and the other to compensate for engine torque. Are there any problems in flight were you would intentionally use a off set in engine thrust for RC Model Planes?
Aren't you supposed to dissconnect one of the ESC's power leads from the cables when running dual? Not sure if the Futaba ones have some sort of smart power management, but I'm pretty sure you could fry a cheaper reciver if booth ESC's feed power to it.
I would, but it really depends on the BEC.
I needed this for my mini kraken!
I noticed the radio you are using is very similar to my Tactic TTX 650. I will try the same set up in it. Thanks
It worked perfectly
Love the Flags At the end :) cool video
Bugga me, I have ben wondering if proportional throttle was an effect of the circuit board/rx or the transmitter, out of the blue you answered my question ( you popped up in recommended video for you section on youtube ), either you or youtube have phychic powers :), thanks mate this video is awesome. I have bought ( and broken ) enough planes for a lifetime, and am know looking at building flying things with my scraps/parts, if it wasnt for your channel i think i would of thrown them away ages ago.If you ever get bored ( lol ) do one for a spektrum dx6i ( if its possible to program that to do the same thing ). Good job tho guys. One weird thing i noticed about your videos, and its you guys yourselves, even when im watching one that doesnt concern me ( liike im never going to build a star destroyer big enough to launch from a truck, but you guys did ) i find that i still end up watching it as you all seem to have personallities that make great tv. If any one of you move to England could you please apply to host the new Top Gear, the show needs you.
Gonna set this up soon on a Bloody wonder twin using Deviation on my 12s ...But have a question on the twin baron what size motors are you using? Looks like a pair of 2204s ?
Can you guys make more videos with Spectrum controllers and reservers?
Please do a challenge where you fly a plane ONLY on the switches on a transmitter. No sliders or sticks.
interesting. i would like to see that one too.
eww no
hi flite test, can you make a p38 swappable/foamie?
Can you guys please do a review on the new 1.2m spitfire by horizon hobby?
Quick question: Instead of using channels 5 and 6, can't I use channel 5 and original throttle? Because then I'd have one channel left for a servo to open cargo doors and what not.
Does it matter which motor is mounted on which side of the wing? I know to run one cc and one ccw motor to counter the torque roll but does it matter which side they should go? CW on left or right ect...
What would be a good transmitter with the 4 mixing options. I wanted the fs-t6 but I think that only has 3.
I think about getting that radio(newer version). What can you tell me about gimballs how much worse to these feel compared to frsky taranis?
Very nice and simple video. This is probably a hack you don't read in a official manual. 👍😃😃
Nice one! Can you guys do a review of flysky Fs-T6 ? Really really appreciate that😁😁😁😁
I have had one of those radios for years now it is really good I never have problems with it, but there is another model that can give you more programming options if you want to do things like this.
if you're at 100% throttle, is there any throttle "travel" left to go in either direction? Or are you subtracting throttle then? If so, can you only turn in one direction?
How about showing for a Hitech Aurora 9 or HT 7 pro?
@FliteTest What lipo should i use if i fly 2 Motors? I have two 2S brushless motors should i use then 4S and 3S ESC's????
can you do this with a spektrum dx6i - we need it for the sea duck
Would it be possible to use a yaw control gyro with differential thrust?
If I have a 10 channel and I bus then would i be able to have flaps, landing gear, etc. also can I do differential thrust on the tgy i10?
EXCESSIVELY LOW THROTTLE!
Okay, so maybe I missed a post about this, but:
I have a Spektrum DX8G2 and I followed this setup. I am flying the FT Sea Duck with the Power Pack C (Emaxx GT2215/09 motors). I tried running a 2200mah 50c 3s battery and it was a pain to just keep the plane from stalling. I tried my 3200mah 30c 3s battery and it was pretty much the same thing.
I notice that when I am full throttle and use the diff thrust, one motor cuts down and the other one still revs up quite a bit. This tells me that my issue is the radio setup, not my hardware. How do I set it up so that my throttle is actually 100% when I set it at 100%?
Just a thought...
... could you use differential thrust to make a four motor plane, without any flaps at all?
You guys use to be all spectrum. I miss that.
spektrum is overrated. I use a frsky taranis and have a dsm2/X orange module on it for the smaller blade bnf helicopters 450 size is the biggest i fly with dsmx . for the bigger heli's like my 600 and 700 i use frsky receivers. better range and for the functions on the taranis you would pay big time on a spektrum transmitter. taranis is budget friendly and has so much to work with.
Lol Spektrum, they're just the apple of the rc world. I use FrSky FlySky and Walkera and never had problems with any, plus I'm saving a ton of money in the long run.
+Metallica4Life1995 that's a good one.
I would honestly use FlySky's protocol over Spektrum. I've used spektrum multiple times and ended with up frustration and constant signal drop outs, while the FlySky receiver (Which mind you is a fraction of the price of spektrum) has gone out to 2-2.5 km range with no hiccups whatsoever
Yea definitely is
God it is very complicated. I know these Graupners are great expensive radios but man these are quite complicated beasts.
I did it with my cheap and great FS-i6 which only has 3 mixes and it works!!!!! I used all of the mixing possibilities (it would be nice to have more) but it is just doing what it should, and I only used 5 channels (delta mix + diff. thrust + front steering wheel on the place of the rudder) I still have one more channel for some bomb dropping :-)
Richard .UK. Please could you show mixing on a Graupner MZ12 Pro. I am using the boat model section none the less it seems to be different to your good illustration ? I have downloaded the manual but it seems to me you need a dgree in physics to understand the instructions.
Is this possible with the cheap fs-i6 TX, if the model is a wing (no rudder), but with retracts. Or do I need more channels?
Do i have to cut/pop off one of the + leads for the esc before I connect it to Rx?
Not many people have this radio. nice to know how to do it if I get one though
Is this transmitter good for an fpv miniquad?
Now try this with an idle up on a twin variable prop plane. That should make some tight flatspins. If I'm counting the channels up properly, it should only take 7, leaving one free for lights, or gear, or something.
Does ESC with BEC damage the reciever wenn i plug bot in ?
Are the motors spinning the same way
Do we still need vertical stabilizer if using differential thrust?
Can differential thrust be done with the flysky i6
Na, it's just the old people in Germany who fly mode 1. I think the reason why it is default on Graupner, is because it's the first mode. I have the mx20 and I love it!
Is there going to be a Flitefest west
What if I also wanted reverse? What would I have to change?
can you fly a plane with differential thrust but with no ailerons or rudder
Almost half a million subs
i bought a devo 7 receiver, it doesn't have numbers but it already has names by each port i.e. elev aile thro rudd it only however has one port for the throttle, are these just guides and can i overall these guides, or have i messed up.
Kind Regards
Hi Flite Test,
I was in ohio the other day so i ran hover to your HQ and no one was there, so i left something with a note on it asking for you (Josh, and anybody else available) to sign it and send it back, and i was wondering if you got it?
Hi guys, I have a problem. I want to do this differential thrust on a resque boat (2 motors, no rudder). Only my Graupner mx16 hott has only 3 free mixes. Can you solve this? Forward and backward. Thanks Herman from the Netherlands
Who has this radio? Can you do it for the 2 common radios? FR Sky or spectrum?
Wish you'd do some videos on the FS-i6 for us poor folks that can't afford high end gear. Why do you think we're avid Flitetest viewers and foam builders? I think there's a number here that can't afford the "good stuff". I'll admit it, I'm retired and poor..
I did it with my cheap and great FS-i6 which only has 3 mixes and it works!!!!!
agreed! I have the fs-i6 and u would like some videos on it
I don't do video but if you are interested I can write it down how to do it.. by far not as complicated
I don't have a twin to do it with yet, wanted to know for future builds, thank you for the offer Banati.
Bánáti János hope you see this, would the set up you described work the same on the fs th9x?
I have 2xBATTERY and 2xESC... can i connect the battery to each esc?
Hi Guys
I have a Futaba T8FG
I have looked the mixing program and I am confussed
Can you help
Thanks
Hi I got the same issue. Debating trying to set up a v tail mixer... I’ll have to figure out how to reassign the elevator though...
God, you guys really need to make an me262 kit using this type of thrust
Damn buddy do i have some news for ya
1- Isnt better to remove one of the red wires in the ESCs so only 1 bec is providing power to avoid conflicts?
2- Its as simple as use 2 separated channels for motors and mix rudder with each one of them (in the desired direction) and each mix use a switch to enable/disable.. you can play with how much.. a 100% mix would do one motor stop and the other go full whrn using full rudder
Can this be done on the new Orange tx6i?
Are you guys ever going to bring up the USA Today drone again? You said you would. 😑
What about removing the power line from one of ESCs?!
How do you reset the mixes to neutral?
My radio is hitec flash 7. Its possible with this radio?
Could you build a 3 propellered airplane with a decent size with differential thrust ?
Yeah - Like the German tri-motor used in "Where Eagles Dare". Same winter camo too. That'd be cool.
very informative viedo but i am trying to do this setup on my taranis to fly my super bee that i built
What motors and escs are that?
What about throttle cut ? without it my fingers feel endangered.
Why don't you show us how to program the old Spektrum DX7 for this??? Please??
can u do a tutorial on tuning a quadcopter with naze32?
I'm pretty sure they already have a tutorial
Josh how to differentiate my fs i6 right joy stick thrust
When is this plane gonna be out??
How do you do this with a tactic ttx660?
This is a super late comment but i had to say it because im curious. So i just watched this so i can do diff thrust on my bushmule. However i already have a 7 channel receiver and tenecally i need 8 for the reverse. But i dont see why you guys aren't just mixing throttle to aux 1 then rudder to throttle and rudder to aux 1 its the same thing really just easier in my opinion and 1 less mix and the best still able to use aux 2 for flaps or gear or whatever you need.
you've got 2 power supply's going into your Rx possible damage to Rx ???
the Rx doesn't care but the becs might. just remove one of the positive leads and tape it.
Can I use a kk2 board instead
why am i watching this, i don't even have rc
Cause these guys rock :)
Me too
Because they are awesome. Also yt recommendations are messed up right now.
well alvin it is time you did get rc. It's a blast my friend, find a club or someone near you and get started!
step up your game and buy a drone man! Thats the future
There is a bixler3 in the hobbyking store!!!!!!😆
I want to buy the radio sends to Brazil?
How to throttle calibrate 4 esc's at a same time using flysky fs i6 transmitter if anybody knows about it then please reply me
For anyone using a flight controller (like the eagle tree vector) that doesn't support differential thrust, I wrote this arduino sketch which does the mixing: github.com/fahrvergnuugen/rc-differential-thrust-mixer
Can you do this mix on a FS-i6?
YES you can ( a lot more easier) I did it...
Thanks Banati
Look my post I wrote it down...
Would you guys ever consider vlogingOr filming everyday in the office
I will Youse it für a Tank and i Testet it with 2 Servos and locked my legt stick Grad it spring back To the Middle the Servos is nor working
The Graupner MZ-12, eh. Guess I gotta buy the White Album all over again ;-)
finish the shinden plz
What is the easy proper formula to app lie for weight of plane to proper KV Size of brush less motor Size..So if I have a 8 lbs plane, what size kv do I need. Keep in mind that I have watched 100s of videos. Ive been searching every where. Why is this information not easily available to all the rc hobbest in the world. Brian. I dont need a treasure hunt! I need an exact answer please. Thanks
I imagine there are lots of variables including the air frame itself and lift generated by it moving through the air. I built a few quadcopters recently but just looked at models of the same size and what kinds of components they use. Answers to questions like this or ones about battery life have too many factors not accounted for to really answer.
Also kV just tells you how many revolutions per minute per volt applied. So depending on the voltage you'll get different speeds having a larger radius motor will give it more torque some brushed motors are also taller than others and have variable quality in the windings for the motors magnets and adhesives used for the magnets think it's really a matter of just seeing what's out there and experimenting with your particular air frame.
Hey y'all should put out the vtol Guinea pig
Im using this on my boat
too bad im using old futaba 6ex, anybody knows how to do this.........thanx in advance for your help
you can get a mechanical differential thrust using a V-tail mixer between the rudder and throttle.
Thank you! I've been wanting to try differential thrust, but didn't think it was possible without an expensive transmitter. Never heard of a V-tail mixer before now.
Master Kammelryder thanx for the reply. i think i will try that. I just dont know exactly how to program in the radio, and the exact throws. I will be trying this for my FT Sea duck. thanx once again
can u do a video talking about your tein bloody baron. Like if u want to see this
twin engine bloody bsron
im going
Make a quad that you fly around FPV and catch Pokemon with.
I want a triangle plane, like the circle plane but a triangle!
Bring back the vigen
Yea
the viggen in still for sale. i doubt they will do another video though as it is so old. it was just rereleased in waterproof foam though!
+RCFlightReviews omfg yessssss I can finically fly it in the snow!!!
or maybe use a v-tail mixer? otherwise I've no channels left for flaps.
I have a video on mixing throttle to gear. So ch6 is still open. Search YT for "dx8 differential thrust". Just another way to do it. I did it on the FT Cruiser
Actually, you can do more mixes with a higher channel radio. He just used a 6 channel, but there are 7,8,9,10,12, and 18 channel radios, that I am aware of, all of which should be capable of more mixes. My person favorite are the Spektrum 6,8, and 9 channel radios because they talk back to you.
+Raycefan I think the point was to show it could be done on a 6ch radio. A lot of people can't afford a multi channel digital radio with 10+ channels.
Thank you. I wasn't sure how to reply. So in the video I did years ago I used throttle and 1 extra channel. Which left 1 more available for gear/flaps/etc.
+notasixpack I've no idea why he didn't use the throttle channel and mix ch5 into it either other than not confusing people with references to the throttle channel by using both from the aux channels. I use mechanical mixers anyway to keep the few mix channels I have free for flaperons etc.