That’s July Over

 

We’ve had a heatwave all week, then at the weekend, a weather front has caused torrential rain and wind. I’m rushed off my feet anyway, as we ran another drone workshop on Friday and I’m in the process of getting everything ready for the next one on Tuesday. That’s a four day turn-around, which is the quickest we’ve ever done it. Each workshop takes its toll on the kit as we allow the kids to experiment with things, but resetting back to the pre-workshop state for the next one means me having to check 6 flight controllers, 24 motors, 24 props and 17 batteries. I was going to say that I haven’t done any flying this week, but I’ve had to fly the HubSan quadcopter indoors to run the batteries down and test their duration, charge them all up and repeat. They often don’t get used for months at a time, so I like to give everything a thorough shake-down from storage charge state to flight ready.

As you can probably see from the picture, I flew the new dragonfly 3D quadcopter for the first time this week. Actually, the first flight was two days before the workshop, so we included it as a new frame for the students to have a go with. It’s a beast to fly. It’s very light and the motor supports were flexing on me, so I added an extra support strut to give to the students. That seemed to do the trick. The design works really well with the wings providing a spring for the split motor holder, while providing a rigid support with very little frame blanking the prop. The flight controller also sits in a very good position with regard to the motors too. The battery holder is a bit of an issue, though, but I can work on that. It’s only taken me about 6 months with Fusion 360 to get to this stage, so it could never be perfect. I was really disappointed after the workshop to find that the white dragonfly that I had only painted the eyes onto the night before was missing. We got the yellow one back (smashed), but the white one just disappeared without a trace. I’ve got to 3D print another one now before Tuesday.

One new thing that I tried this time around was to give the students the Taranis X9D to fly with, while I used my Taranis QX7S as the master in a trainer setup. This worked really well and they did a lot less damage than usual. It was quite a challenge getting it to work, though, so I might do a follow-up post on the technology. I’ve bought myself a multi-protocol adapter for my Taranis which allows me to use it to fly the HubSan quadcopters that we use for the workshops. This is an iRangeX IRX4 module which I bought from FlyingTech. It works a treat and lets me choose the protocol using a rotary switch on the back. The only issue was having to turn it off and on every time we switched quadcopters as the HubSan only auto binds on power on. There’s no rebind switch on the unit. Very minor niggles aside, though, it was a fantastic improvement. I can tell when the students are about to crash and cut the throttle to zero. This was what minimised the damage as every time previously they would crash, forget they were flying the aircraft, and leave the throttle at 100% until I could reach over and flick it off. I did try flying them out of trouble a few times, but it’s really hard to do with a quadcopter. If you take over a fixed wing plane with the throttle at zero, then it glides until you find the correct position to fly. Do the same with a quadcopter and if falls out of the sky like a brick before you can do anything. Not great when you’re trying to fly in a space with an 8 foot ceiling. All I could really do was a bit of throttle modulation to try and limit the impact in the times when they got completely out of control and stopped flying. All in all it was a very interesting experience.

Anyway, I’ve got to go as I’ve still got to test the six quadcopter kits for Monday and cycle the batteries. Here we go again.

Two in a Row and the Drone, Tree, Stick Manoeuvre

That’s flying two weeks running now. I haven’t managed that in a while. What I’ve noticed is that I’m not planning ahead what I want to fly any more, rather, I’m just grabbing the old RS352 when I can and trying to get some air time. I should really be thinking ahead and flying the Atom autogyro, but I need consistency in the weekend weather.

Anyway, I almost forgot to take any photos this week as it was really busy.

This is a quick post-flight shot that I grabbed just as I was going home.

Firstly, there was an old friend waiting for me with a new aeroplane. He had been flying it with his son during the week, but it was even smaller than his Champ. It was tiny. This white foam high wing Cessna looking aircraft flew on a single cell with rudder, elevator, throttle and had stabilisation. This was good in the wind, otherwise the rudder control was very hit or miss. You wouldn’t call it agile, but, put in a good solid rudder command, and it definitely did go where you wanted it to. With a bit more power (or a lot less wind – this was 10mph) it would be even better. We both had a go at flying it, which is unusual.

We had noted that somebody had come over with a drone and kept well away from us as they tend to do. At one point we could see him chasing down the field after it, obviously out of control. Then I flew my RS352 on its first flight of the day and the drone flyer did the sensible thing and came over to have a chat with us. He was a really nice guy, but his drone had some real issues with range. It was a VN10 Eagle Recon Drone, which he let me have a go on. It has a very strange throttle, where it is spring loaded to sit in the middle, then up or down controls your vertical speed i.e. it’s not really a throttle, but good for beginners to get the hang of it. There are lots of other buttons on the strange looking controller and it also takes pictures. It’s not bad to fly, but it does have a serious range issue. We’ll come back to this in a bit, but another guy turned up around this point. He’s the one whose small white foam model I crashed for him over a year ago due to radio failure linked to an incorrect prop and an overloaded ESC. He was flying while I was having my second flight with the RS352, but he still wasn’t having a lot of luck with it. Even turning down the gyro, it still looked a handful and he eventually crashed and broke the wing. At this point we both noticed that the guy with the drone was busy looking around in the grass at the extreme edge of the field. He had obviously lost it.

This is the errant drone.

Much searching of the grass followed, but no drone could be found. That is until I heard an odd noise of an object falling in the tree next to us. I thought, “that’s either a big pigeon falling out of a tree, or a drone has dropped down a branch or two”. Basically, it was just instinct that I picked up on it and, sure enough, there was the errant drone right at the top of the tree. So, what followed was the drone, tree, stick manoeuvre, resulting in us recovering it perfectly intact. He actually flew it again later. I’m glad that he was so much better at stick throwing than either of us, because I could never have lobbed the stick as high, or with the accuracy that he did.

So, we have one drone back, one damaged but repairable foam glider and one further casualty to report. As we were recovering the drone, a father and son walked past us with what looked like a white foam Wot-4. We saw them fly it from a distance, but I was a bit baffled by seeing what looked like a 27MHz sized aerial on the transmitter. We were too late to help them before they tried the first take-off from the ground as we all saw it lift off, roll over to the right and crash. It looked like something came off, which I think was the rudder, but the pair of them were huddled over the bits for quite some time. By this point we had got back to the centre and expected them to come over and we could look at the plane for them and have a chat, but they went straight back to the car park. Oh, well. Maybe next time?

Then, almost as I was leaving two other guys turned up with lots of FPV aircraft, deck chairs and a helicopter. One was flying around with his FPV plane that looked like a Bixler or Multiplex Easy Star pusher layout while I was having my fourth and final flight of the day with the RS352.

That’s all I can manage for now, as I’ve got another Drones masterclass to run this Friday and desperately need to set up and test 6 micro drones. I’m playing with an iRange multi-protocol module for my Taranis so that we can use a buddy box setup with the HubSans. I didn’t know these things existed, but I’ll post more details if I can actually get the thing to work.

Mainly Just me and a Skylark

It was very quiet today, but I did finally manage to get some flying in.

 

The weather was strange too. I got woken up this morning at about 6:30am by torrential rain hitting the roof. The clouds had largely cleared and was looking hot and sunny by 9am, so I thought I’d take my coat just as a precaution. I was both so hot I felt the sun burning me, but not long after I was so cold I was grateful for my coat and jumper and wanting a fleece too. It’s weird old weather.

This is summer.

Anyway, I had two quick flights with the RS352 and then two recharges. I was all on my own for most of the day, apart from a guy with an Inspire who always chooses the part of the field furthest away from me and never talks to me. Then, just as I was about to go for flights three and four, I see a guy walking across the field with his son carrying a small red ArtTech Cessna looking aircraft. Unfortunately, there was a problem with it and I advised them not to fly. This particular aircraft was quite old, never flown and had been given to them by a friend. It used 35MHz radio, we presume a brushed motor, and originally ran on NiMH cells. These had been replaced with a 1300mAH Li-ion battery from a camera, which seems to be where the problems stem from. It doesn’t have a high enough C rating, so there was not enough power to fly. Even more serious was the fact that its owner told me that any throttle setting above about 50% caused total power failure – loss of both thrust and control. No way would I fly that. So, we had an intelligent discussion about all things radio controlled aviation and he seemed like he really knew what he was talking about. He just needed some guidance in the right direction. I’ve got high hopes that they’ll fix the problem and come back.

I didn’t feel as rusty when I was flying this time, and had four really good flights. However, my flight lipos need replacing and my main 12v Lead acid battery has had it. Mind you, I did buy it from Sandown Park model show over 20 years ago and it definitely wasn’t the last year it was on either. It’s had a very good run, but I should buy another one. My second charge off it depleted the battery completely, when I should have been able to get at least 3 or 4 full charges out of it.

Finally, the date today marks two years since the maiden outing of my autogyro. I’m sorry to say that I really haven’t made much progress with it recently. It’s still sitting there on the table looking at me and waiting to fly. I need to remedy that situation. The mini autogyro I designed just needs its radio installed though. I think that’s the way forward.

Funny Old Weather (part 15)

I would have been on the bike this week anyway, but it was raining when I got up this morning. That’s after a week of 30 degree tropical weather when it’s been too hot to do anything. Last night and early this morning we had heavy rain, which was such a relief as it cooled everything down. Then, all through this morning, it’s been overcast with a light mist of rain in the air, but looking like it’s about to turn heavy at any moment. Now we’ve got into the afternoon, and it’s back to hot, humid and sunny. But enough of the weather report, I’ve got a drone workshop to prepare for.

 

Here we go again. I’ve got to prepare six working micro quadcopters from what was left of the wreckage from the last one in March. I just haven’t been able to face soldering the flight controllers in the 30 degree heat, so today has been a bit of a relief. The soldering is almost complete as the temperature is starting to rise again. I really can’t understate how bad it is holding a 200 degree soldering iron when the ambient temperature is 40 degrees.

In my hardware order this time around, I’ve added a multiprotocol transmitter module for my Taranis QX7S. I didn’t realise these things existed, but it’s a module that contains the A7105 protocol chip used in Hubsan radios, plus some open source software to make it work. There are other protocol chips like the Syma, FlySky and Walkera too, so it can be used to control a whole load of cheap “toy” quadcopters using the Taranis. Now, this is good, because we have two Taranis transmitters, so I’m planning on connecting them with a trainer lead and flying using a buddy box system which will improve the flying part of the workshop. Basically, I can take over and fly when the students lose control, which should make the hardware last a lot longer. It’s going to need some setting up and testing, but it looks like a really good idea.

So, the rest of my day is going to go like this:

1. Fix remaining flight controllers, install in drone, test.
2. Finish dragonfly model battery holder (I hate Fusion 360), ready for 3D printing.
3. If time, make improvements to the bug and turtle.
4. Design a new “AXE” drone – TOP SECRET.
5. Look at the electronics for the 6 gram lidar that I bought ages ago and forgot about.
6. Updates to the quadcopter and fixed wing flight simulators.

And finally, I do have the movie completed for the mini autogyro build that I did a while ago, but it’s too big for me to upload on Vimeo. I’m going to try compressing it and then probably set up a YouTube account instead. The electronics to make it fly is on the order with the rest of the drone workshop kit, so that’s not going to happen just yet.

OK, well that’s a full schedule of work planned for this afternoon and evening, so I had better get going.