From Queensland University of Technology:
Queensland University of Technology and the Commonwealth Scientific and Industrial Research Organisation (CSIRO), Australia’s national science agency, have announced their next international unmanned aircraft challenge, UAV Challenge Medical Express 2016.
The previous UAV Challenge, held in 2014, tasked entrants with designing and creating an UAV that could deliver an emergency package to a hiker lost in the outback.
Announcing UAV Challenge Medical Express 2016 at an unmanned systems conference associated with the Avalon Airshow, event co-ordinator Dennis Frousheger said the 2016 challenge was designed to push UAV technology to the limit.
“It’s unlikely that traditional fixed-wing unmanned aircraft or small multi-rotor vehicles will be capable of meeting this challenge – new hybrid flying robots will probably be required,” said Mr Frousheger, an engineer in CSIRO’s Digital Productivity Flagship.
“This time, our hapless bushwalker is stuck in a clearing in the Australian Outback, surrounded by floodwaters, and his doctors have requested an urgent blood sample be sent to them. He’s found his way to a clearing and has emailed his GPS coordinates.”
“Joe’s located in an area surrounded by obstacles so teams will need to develop systems capable of understanding the landing site, and plan and execute a landing – all of this at a distance of at least 10kms from their location.”
To complete the mission, teams will need to deploy an aircraft from a small town outside the flooded area and have it fly autonomously for at least 10km to find Outback Joe. The robot aircraft must locate Joe and automatically land nearby. After Joe places his blood sample into the aircraft, it must take off and fly quickly back to the town.
UAV Challenge co-founder Professor Jonathan Roberts, a QUT robotics expert with the Australian Research Centre for Aerospace Automation, is not expecting a winner in the first year of the new competition – but is happy to be proven wrong.
“It took eight years to save Joe in our Outback Rescue competition – that’s with more than 2,000 people from 350 teams working on the problem and sharing their knowledge,” Professor Roberts said. “We’re expecting many of those teams to take up the medical express challenge, along with others keen to push the envelope for UAV capabilities. The prize for saving Joe will again be AU$50,000.”
The competition will take place in September 2016 in Outback Queensland, Australia.
Comments
Thx Sam
Just made a new post to discuss.
Hi all,
The first version of the 2016 rules have been released: https://docs.google.com/file/d/0B5JgqjkRDqw8dTllN085ZTJyNjQ/edit
Cheers,
Sam
Hi Rob, interesting to know that even at 10C they are overrating the Multistars.
I have several places that say that the 2900mah Panasonic 18650 PF and PD lithiums are capable of 3.4C continuous, the only place I haven't actually been able to confirm it at is Panasonic who have no online information at all about the PD and PF.
Sadly, Panasonic is very quiet about these batteries.
If 3.4C is the case, I really think we could work with 3.4 C.
I haven't even gotten to 5 C on my Extended arm Flip FPV Pro as I hover at about 1/3 throttle around 2-3C.
I will try to dig deeper.
Thx Rob.
Yeah Sorry you got the GA right! ;)
In considering your advice I now am now more interested in a VTOL with the least amount of tilting mechanism and a optimized fixed prop drive for both hover and forward flight. Conceptually do you think the Lotus I linked to above is a good compromise otherwise?
My concept so far is that if most hover lift is produced wing tip motors, where most of the weight (COG) is as well, then a third tail mounted motor that also tilts for forward flight, is merely there to "balance" the whole affair in hover. A tricopter has the least amount of components to maintain hover, and if the wing tip hover blades form part of the wing (as in they recessed into the wing) in forward flight there should be less drag. I have some ideas how to get rid any folding mechanism entirely and simplify the drive train some more. I'd also like to decrease the wing area as much as possible to make it small, portable and under 3kg, preferably even 2kg if possible.
Would you be interested in a co-development of such an aircraft? Or possibly offer design advice?
Regards JB
Rob: here you have a video of a high endurance (in process) quad fliyng in windy day; the first part is near trees to have the "evidence" ;), the second part is 30-50 mts on open field to test flying; I'n not a good pilot but I have a great code that can drive this truck with 35-40km/h winds, is not for take a smooth video but can fly FPV and take same reasonable photos, only thing that's didn't work well was landing today (last video), it's lands faster than always this time, no crash but not good land to visit Joe. I hope than you and other developers are doing a better job than imagine :)
tarot 650 windy day from Linca on Vimeo.
I assume GA (General Aviation = full scale?) VP props are designed for maximum efficiency at typical cruise conditions, and then everything else is a compromise.
I wouldn't hazard a guess as to efficiency of VTOL. But if I just had to take a crack at it, I'd go with dedicated lift motors/props, and then a single dedicated pusher. The requirements for the lift motors and the thrust motors are just far to disparate. If you try to compromise, it'll be... heavily compromised. The weight of a single pusher will be well less than the conversion hardware.
Thx a bunch for the explanation Rob. Makes sense.
How do the GA VP props compare? Do they use a taper?
But what happens when I take both a VP quad and a fixed wing and blend them into a VTOL? Won't the efficiency of the wing compensate for the losses of the VP quad? I would tilt the VP rotors for forward flight. I only use the VP quad part for takeoff and landing, so say about 2-5min of flight hover and then some 30minutes of high speed forward flight using the wing. By doing this I'm hoping to use 40A or so in hover but then less than 10A in forward flight to cover the distance search area required. We got our Skywalker X8 down to 7A at 18m/s so I'm hoping for about the same but on a much smaller wing/airframe. I'm thinking that I should be able to use a fast wing, one with a high stall low drag, because i dont need to worry about takeoff/landing velocities as the VP will get the wing to flight speeds.
For imaging ops endurance is irrelevant only range is required to cover ground. The faster the better for SAR. I just want it to be able to VTOL, not really hover for long periods.
Do you think the combination has merit? Or would a fixed prop work better than a VP quad? The transition is always the killer i know. Have you seen this one? http://www.jobyaviation.com/lotus/ or this one that uses APM? http://www.wingcopter.com
Regards JB
JB, if there's not amp ratings in that thread, then I would really be guessing at this point. It's been too long and if I didn't write it down, it's unreliable. You can work it backwards. 25 minutes from 4S 10,000 mAH at 3300g. 24A. Or, 25 minutes at 4S 5000 at 2050g, 12A. Those seem about right.
Or was I using the 4S 8000 Multistars... ?
Oh hey Gary, you asked about my 5C comment on those. They are rated 10C, but I have found they puff if you draw more than 5C for more than a few seconds. I did one flight on my quad where I was pushing it, drawing... not much more than 40A from a 4S8000, and it puffed a bit.
So why are VP quads less efficient? Two reasons.
First, and this one is easy, efficient props have the perfect taper and twist, engineered for the designed airflow. However, VP props typically are slabs, with no twist or taper. You could have taper, but nobody makes them. And the twist will only ever be correct at one specific pitch angle.
Look at it this way: What is the angle of attack out on the tips of your nice efficient fixed pitch blades. Maybe 4°? Maybe even 2°? Well, you're going to want somewhere around 10° of pitch variability in your design. If you design with twist, such that optimum efficiency is occurring at the mid range, at the minimum pitch setting, the ends will actually have negative AoA. Ooops.
Second thing, is that to operate as intended, variable pitch props must have "thrust reserve". ie: they must be spinning faster than they need to, at a mid-pitch setting, in order to be able to generate more thrust at full-pitch. If they were spinning at just the perfect speed at mid-pitch, when you increase pitch to generate more thrust, they will stall.
Basically, the most efficient rotor rpm, is the one which has the blades close to stall. So going for efficient flight, you are tickling the dragon, trying to use the lowest rotor RPM you can get away with, while still having enough reserve power to be able to climb and manoever. This measurement is called Ct/Sigma. Typical RC Helicopters operate in a range with a Ct/Sigma 100-1000 times below the peak (not linear). I'm increasing efficiency by operating in the 10 times below range.
So, variable pitch props are always going to be less efficient than an equally loaded fixed pitch prop. Again, because the blade design can't be optimized as well, and because they need to be wasting power spinning faster than peak efficiency.
However, helicopters have an advantage. Because it's so easy to have such a huge disk area, they gain much of that lost efficiency back through the Momentum Theory. That is, lower disk loading, is more efficient.
A VP quad, is the worst of both worlds. High disk loading like a FP quad, but then inefficient rotors like a helicopter.
The CY quad is cool, and flies really well. But remember, it only flies for what, about 5 minutes?
Rob
You dont have an amp draw for cruise with your 500 heli you'd like to share? :) Would be helpful for me to run some figures. Thx.
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With VP quad I can agree that they're mechanically more complicated, but one benefit they have on a tilt rotor version is that the prop pitch can be adjusted for efficient foward flight. They aren't that complicated though, have much better control rates, better wind penetration and allow for larger props to be used without extra response latency.
Rob what is the reason you think a large VP prop quad wont be effcient?
Wouldn't a tilt rotor VP using a very small (+40-50kmh stall) wing for foward flight and small props for hover always be more eficient than a heli even though the hover itself might not be? Im thinking hovering will be limited to just 2x takeoff and landing so a tilt rotor would be ideal to achieve those objectives.
Here is a reference to Curtis Youngblood's gas engined variable pitch "TEST" quad as presented here on DIYDrones.
http://diydrones.com/profiles/blogs/curtis-youngblood-single-motor-...
It does work, but it is mechanically complex and since the test version, I haven't heard any news that Curtis was actually thinking of producing these.
Watch the video - talk about flying lawn mower, more flying brush-hog.
What can possibly go wrong.
One advantage of this design over normal multis is that there is zero prop lag since you are keeping more or less constant speed and just changing pitch which means extrmely fast response as can be seen in the video, but glad Curtis is flying it and not me.
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