First off, Thank you to Sam, Greg and everyone else in Greg’s thread for the info I have been lurking and trying to absorb as much as I can. This is the build I wanted to do a couple years ago before I got into quad racing. I’m just waiting on a few more parts that should be here this week. I’m trying to follow the Mozzie blueprint as much as possible. I’m waiting on the carbon from Australia since I couldn’t find that size in the US.
Parts:
XUAV Mini Talon
Pixhawk 2.1 /w Here GNSS
Mauch Hall sensor(200a)
TBS Crossfire Diversity RX
Demon Core v3 PDB 200a
EMax ES08MA II servos
Fwd Motor: Cobra 2814 1050kv
Fwd ESC: Cobra 40a wing esc
Fwd Prop: APC 9x4.5 (i need to revisit this since I don’t need to launch as a plane… I went by the Cobra chart when i picked up these props)
Quad Motors: TBS Endurance 2206 1450kv
Quad ESC: Spedix IS45a
Quad Props: HQ 7x4.5 I should get 1.1kg thrust per Motor with this setup
First Question:
I’m putting the CNX pod out front with a pan tilt servo for a swift 2 flight cam and Session. I’m getting worried about being nose heavy with the front quad arms on the nose as well(mozzie). Does the way Greg has them mounted high right behind the pod cause problems? Greg’s seems to fly fine.
HI Josh !
I plan to build the same project than you. I just received the fuselage of the MT and need to choose motors/prop.
I finished a similar project (vtol with pixhawk on a 1900 skywalker) but it was a prototype and not really a clean build. However it flied well !
I Will use a CF plate for hover motors like mozzie configuration.
Do you know your estimated flight time with your configuration (with about 2min in hover mode) ?
I’m looking for an efficient configuration with a simple pan and tilt fpv camera in front.
Sebastian, do you have any post or a photo from your skywalker build? When I finished my phantom flying wing vtol I plan to make vtol my old skywalker, thank’s
Sebastien, This is my first VTOL build but the Mozzie looks to be getting 75mins with only using the quad motors for take off and landing. My goal for this plane is 60mins. Will be used for mapping and search and rescue.
Greg, thanks for the link. That would have been much faster than waiting on a package from Australia!
If you are running a 8Ah or 10Ah Multistar pack or similar weight, you should be fine with mounting a pan/tilt on the front of the MT with the CoG. In our configuration with the avionics enclosure and a 8Ah battery it still needs a good 100g of ballast up in the front nose as well to get on CoG. Feel free to ping me with any questions BTW.
@GregCovey Thx for the link, I’ll be adding the CF flat bar link to the docs, with some other stuff shortly.
Thanks Sam… To start I’m going to use 2 4s tattu 3700 in parallel since it is what i have for several other applications. they are 40g heavier than the 8000mah multistar, but with room to move them back if needed so in that case I should be fine mounting the front Quad arms in the mozzie spot.
Now the problem is going to be getting my big hand into the nose to mount the backing plate, lol. I guess that only needs to be done once.
Ah for mounting the quad arms backing plate I put some velro on the leftover cutoff from the CF bar (or anything similar), and some velcro on the backing plate so I can feed the screws through and direct it properly. Once the screws are in the locking nuts and tightened against the foam you can just rip the velcro apart. I also put some UHU Por glue on the top of the backing plate, so I never have to do it again
You should have plenty of room to move the batteries back. Probably about 150mm.
Ah yeah and one more thing, the placement of the quad arms is also CoG sensitive. So where they are on the Mozzie is the same distance front and rear from the COG point.
I debated starting a new thread for my question, but decided to reply here instead. I hope Josh doesn’t mind my riding his coattails on this thread a bit. There is already a lot of QP expertise chiming in here.
I have been watching Greg, Sam, Tridge et al on the quadplane stuff for a while, with curiosity, but no burning interest to build/own/fly one. Until now. I have a new mission profile that might best be served by a quadplane. Goals are:
Multi-hour endurance, possibly augmented by ArduSoar logic, and/or PV cells on the wings.
Li-ion flight pack for better amps per gram.
Downward facing video camera with 2-axis gimbal. Probably Mobius or similar. Ability during flight to toggle HD recording on/off, switch to JPG’s, and always have FPV option from that cam. Probably video switcher with forward facing basic FPV flight cam as well.
Urban rooftop launch and land. With sufficient tractor motor/esc/prop combo, no need for VTOL takeoff, only VTOL landing.
If I had to pick an airframe today, it would be a Radian or Radian Pro, admittedly largely because of familiarity. I am wanting a high endurance motor glider, and believe a ~2M foamie is a good starting point.
Foamie because of low cost, in case, God forbid, something bad happens.
Assuming I go weight-conscious on FC, OSD, ESC, cameras, Rx, VTx, etc., looking to have just enough quad thrust for a controlled roof-top landing. My initial back-of-the-envelope calcs suggest I could get all the above in around 1200g AUW, before adding quad gear.
Provided you have enough current rating on your Lithium Ion cells landing 1.2kg with a quad setup is easy. You should be able to do it with a set of KDE 1806 on a 5x3 prop with 2:1 thrust to weight ratio and hover at around 20A. Two KDE 1806’s plus 2x 20A ESC’s and flat bar CF quad arms should only weigh around 120g each, so 240g for the whole QP setup. Another option is a parachute…but you won’t have much in the way of landing accuracy. High pitch reverse thrust might be another option for landing, or belly stitter config on a wing.
Solar is possible, Banggood have some MPPT controllers for around $70. PV cells are an issue on the wing, legit Sunpower ones bend at least and have good conversion. Would need to know what the cruise requirement is of the plane to see if solar is worth it. 1.2kG with solar is very lightweight for a 2m foamie, Radian weighs 980g by itself? Even 4s2P battery is 400g. So maybe more like 1.6kg? Soaring might be easier and lighter to make proper use of and like solar would depend on flying weather.
The other question is if you really need endurance or range. They aren’t the same thing. If you need endurance then solar power becomes more likely, if you need range it’s less so unless you can sustain flight with solar power alone. It also strongly influences the optimisation of the forward motor/prop combo. So you’d be able to do one or the other. The quadplane takeoff (and landing) can also improve the flexibility you have in selecting the best forward motor/prop combo as you can neglect static thrust for forward flight takeoff.
On the avionics and imaging side that’s all possible, and reducing the size and weight of the required payload to a minimum is essential in reaching endurance and range. Gimbals etc add weight. The other question is if you need endurance do you need comms range, like LTE modem. If so then a CC (Companion Computer) is required, but a raspi zero W could do all the required, including 8MP imaging, FHD video FPV over wifibroadcast running Maverick. Will also provide a telem path for GCS, and cost less overall. Otherwise, LTE range is limited only by your aerial cell coverage (as in it can be on the other side of the planet!), data is fairly cheap in most places, and you can easily use Zerotier to punch through the Mobile phone NATs to connect from and to anywhere.
Thanks Sam. Extremely helpful information. Couple thoughts in response:
Last time I weighed AUW of one of my foamies, it was a Radian Pro with an 1100mAH and full Vector setup, at 1178g. Vector et al is ~180g, and that was before I moved to Ardupilot. I believe my non-motor/non-ESC electronics would come in well under the older Vector 180g mark. So before adding quad gear and possibly PV cells, I think ~1200g is achievable.
Good question re range vs endurance. I need endurance, not extreme range. I need to loiter within a few mile radius for a few hours, at a fairly constant altitude.
The great thing about ArduSoar is that it weighs zero grams.
Flights during daylight, in high radiance climate/location.
Re control and video, I was planning on forthcoming Dragonlink Nano Rx (UHF, very lightweight, fully bi-directional mavlink telemetry), DL OSD, and 1.3GHz VTx. That said, I am starting to play with a SBC (Rock64) and a USB3 board camera for a land-based application. Putting something like the RPi zero W in the bird would be fun.
A follow-on thought: you quoted hover amps. I’m not sure I even need to hover, to be honest. Just a “controlled crash landing” of sorts. Is it possible that quad system would be small enough, light enough to just manage something like a meter per second descent at near full throttle, and if for some reason the landing’s not looking good, go 'round with front motor? Never having flown a quad plane, I know the transitions between hover and forward flight are the most critical part. That said, maybe I shouldn’t be so cheap on hover, as landings would be more relaxed with full hover-level quad thrust.
Also, is it possible to estimate the mAH needed for a VTOL landing? I might inadvertently get my crash landing if I wait too long on flight pack.
Haven’t used the 8AH in a while, but when we tried them last they’d only sustain about 2-3minutes of hover before coming down. They are 2 years old now though and have done their share of work
You should still see over 60minutes of forward flight with limited VTOL time at a few minutes. The biggest issue is always the high current on landing with the quad, not necessarily that the batteries are “empty”. (40A in hover vs 4A in flight)
