Nothing revolutionary, just a printed quad that can take the Sony range of mirror-less cameras. Am awaiting delivery of the Herelink unit to complete build. The rest of it - Pixhawk Cube, SimpleBGC, Tmotor 4 in 1 F55A ESC. Batteries from 8000-16000. Expecting 25 mins from 14,000 6S. The Herelink will replace so many onboard units and antennas like - RX, Telemetry radio, Video TX, HDMI converter.
Posted by Vince Hogg on September 1, 2015 at 5:13am
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.
Having completed many UAV filming jobs from locations without vehicle access I was looking to improve the logistics of getting the equipment on site. I have occasionally left some vital components in the car 2km away I wanted to have everything (except the copter) in one box.
An old golf caddy was shortened to allow it to stand more upright and modified to allow the toolbox to clip on. The tray clips onto the handle with 28mm pipe clips.
I am using a 12v 7Ah PB to power a TFT screen, Nexus7 tablet and VRX. The weight of this battery makes the base very stable. The video feed is repeated in the fatshark goggles.
The octa arms fold and it can be carried on top of the box, leaving one hand free.
Posted by Vince Hogg on December 12, 2013 at 11:55am
Our Holden Drone has been finished for some for some time now but I have not had time to edit and upload any video until now.
During these two merged flights we were testing most of the Arduplane modes including some tight figure 8 waypoint routes around the field. RTL, circle and FBW all worked well. This was all done line of sight with no FPV equipment.
The current wing is rather heavy so we will make another with 3D printed ribs over a square section carbon spar. This will save about 1Kg. We will probably also add flaps as its glides rather too well when trying to land.
I am currently working on a narrow gopro gimbal for fitting in the nose which will also fit in our H quad fuselage.
Following on from the very successful H quad with vibration isolated arms I decided to build something that would lift a DSLR or larger.
Is seems a hex has marginal chances of surviving a single drive failure so I opted for an octa. The H8 was quite an attractive layout but the loss of efficiency and lift was too much so I decided to build a flat 8. It also had to fold down to less than 35cm wide if possible. I wanted to keep a vibration isolation system but the method used on the quad was not suitable. I opted for a separate frame which carries all the heavy and vibration sensitive items like controller and camera, all suspended on silicone ‘O’ rings. Rings can be added or tightened to ‘tune’ the system. Provision is in place for z axis O rings if required but with 6 rings it each corner it is already very stiff in all axis.
I was part way through the build and struggling to get the folding arm system working nicely when my son ordered a 3d printer. I was very sceptical despite their popularity on this site.
After the first few printed items came off I wondered how I ever managed without one and my poor son didn’t get a look in – sorry Leo.
Once all the plastic parts are printed it doesn’t take very long to cut the carbon to length and assemble it.
eCalc suggests it will have a max TOW of 8kg (inc 3.3 kg payload) and hover time of 11 mins at that weight. More realistically, with a DSLR and 4 x 5AH 4s is should be about 5.3kg and 22 mins. (This is using MT4008-12 with 14x4.7 props)
I am considering a production run of these frames once this one is proven.
This was the biggest test so far for my 'low vibration' quadcopter. The quarry was surrounded by professional film crews so it was with some trepidation that I took to the air in 15kts of gusty wind.
The intention was to 'park' the copter in the correct position and then concentrate on camera angle but for some reason the well tested loiter didn't hold position and got blown downwind. I suspect it was just the strength of the wind or possibly the compass getting affected by the towers. There is some indication in the tlog of 30deg shift in compass at that moment. Anyway it was all flown in STAB.
Frame weighs about 60g less than Mk1 with much more room and accessibility to the nose sections. The arm O rings mounts are more firm than the Mk1 but vibration levels about the same. All RAW x,y,z accel vib about +- 1.5. Its possible to fly without reversed motors but the YAW rate is still much better with them reversed. As the arms are enclosed there is no problem if an O ring brakes and it has been flown with two missing on the same side.
I am now working on an internal nose gopro gimbal.
Posted by Vince Hogg on January 29, 2013 at 2:28pm
Have constructed an enclosed ‘H’ frame carbon/Kevlar quad with soft mount front and rear arms for vibration reduction. Initially yaw was awful as the arms tilted in the wrong direction and opposed any motor torque so I had to stiffen the mounts to prevent yaw reversal. Now I have reversed the motors in the code and the tilt actually helps the yaw. The mounts on the video are very soft, just to help demonstrate the movement but I think they were bottoming out.
Am quite pleased with the lack of vibration showing on the camera.
Apart from the motor reverse all parameters are completely stock. Will tweak them when I get some time.
Posted by Vince Hogg on January 19, 2013 at 2:23pm
Having seen a vast improvement in the Arducopter handling when vibration was reduced I decided to experiment further. I thought it was worth trying to soft mount the tubes so cobbled together a test frame on a bit of 4x2. The 12mm tube mounts are held in place with ‘o’ rings. The video is with standard 75 shore rings 17mm ID. This was just the first test so was quite pleased but will experiment with other types/sizes.
This method will probably only work on a ‘H’ frame where the motor lift balances out.
Posted by Vince Hogg on November 26, 2012 at 9:00am
There is not a great selection of decent 3 axis camera mounts for gopro sized cameras so I have started building my own. The first one will be a ‘nose mount’ and I may later consider a belly mount for quads etc. It will have one standard sized digital servo for roll and 2 micro sized ones. The belt drive gearing is to increase the rotation angle up to 280deg. All pivots will have deep groove ball bearings.
I hope to mould a thin carbon fibre cover for rain protection (it hasn’t stopped here for 6 months).
This will fit on the nose of the Holden UAV, which has now had many successful flights with an APM2. More of that