I would like to share my latest 7kg multicopter design with the DIY drones community.
Having designed and operated fixed wing, helicopter and multicopter camera systems for a number of years now I have learned what is important, at least to my operation, namely low vibration, endurance and ease of use.
The first two are fairly obvious but the ‘ease of use needs a little more explanation.
I guess many of you will have suffered from drone pilots back after lifting and carrying an awkward heavy octa around. Even working on the central electronics can be difficult.
I set about designing something that was a pleasure to operate, from building, transporting and flying. My other designs were ‘one offs. and often had time consuming carbon laminating but this Q7 is built from 2 sizes of carbon tube, fitted together with 3D printed ABS and is easily reproduced.
This Q7 (quad 7kg MTOW) can be quickly dissembled to various levels. As shown in the video, folding the arms and lowering the GPS gives a very easy to carry unit.
The new (in house) 3 axis gimbal is on a quick plug connector (thanks Leo) so by loosening 2 knobs it can be removed in seconds and the copter legs folded in. (gimbal in photo above is older 2 axis one)
To get even smaller, the 2 end units come away easily, with no wires to disconnect. We may use folding propellers to reduce packed size of end units further but this may compromise endurance.
Lastly, the central (rainproof) electronics unit can be removed. This is still fully functional (without motors) and can be tested & adjusted on the bench.
The system as currently set up with a Sony Alpha is achieving an honest 30 mins flight time with 2x 6s 8Ah at 4.5kg. Each pair of arms is isolated on sorbathane so very little vibration is transmitted to the centre frame.
I know there will be questions about a ‘serious’ copter with only 4 motors and that is a very interesting debate. I designed and constructed my Octa because I was concerned about survivability after a motor failure. Since then I have monitored various sources and noted reasons why UAVs crash. It seems to be extremely rare to have a good quality motor or ESC fail. Loose screws or wires would defiantly go into operator error category.
We already have a number of requests for frames so we are currently setting to more 3d printers as this is a but of a bottleneck.
I would like ‘expressions of interest’ so I may judge how seriously to consider a larger production run.