Freesteel Blog » Weekends

Wednesday, May 25th, 2016 at 12:58 pm - - Hang-glide

This was Sunday (yesterday) on Tailbridge Hill while Becka and friends were attempting some 80 mile massive cycle ride including a race up Great Dun Fell (844m), somewhere square in the middle of that dark grey wall of rain and hail to the north of me.

tailbridge

They didn’t make it. I suspected that something bad could happen in that area on an otherwise sunny day because of the RASP forecasts:
dunfellrasp
They were to the NE of Kirkby Stephen in the blue, and I was to the SW in the place with the nice thermal updrafts. I already knew no one was interested in my weather observations if it could lead to a change of plans, because they’d all been on a futile journey walking up a hill to a flood-prone cave on Saturday when I knew two strong cold fronts were predicted to pass overhead and make everything miserable.

I got into my own spot of hail up at the clouds at 1300m over Mallerstang Edge late in the day, and it was nice witnessing this three-dimensional field of white pixels streaming past.
mallerhail

I don’t have time to edit any video, so here is a video with a bit of hail in a flight last month from Builth Wells.

I had to do a better landing yesterday, because in Yorkshire the field boundaries are made of rocks.

Thursday, April 28th, 2016 at 12:04 am - - Flightlogger, Hang-glide

Well, the hang-gliding has been quite lovely. But the logger appears shot to pieces.
cloud
I still don’t know what I am doing when I get to cloud-base, which is probably why I plummeted out of the sky shortly after this picture was taken.

As soon as I took off, the barometer stopped communicating most of its data.
badbaro
This is the device I lavished so much time on isolating it from the rest of the electrical circuit and arranging for it to bitbash the information back through an interrupt pin.

It could be some timing issue, or whatnot. No way to debug it. Luckily I got myself a Bluefly vario which does the same thing of reading a MS5611 barometer on a tight 50Hz loop and transmitting it back to the main board. In the Bluefly’s case it’s for the purpose of running a Kobo/XCsoar system. I’ve just given up on the one I built as it’s too inferior to simply running XCSoar on the phone where I’ve got colour and more or less know how to use it.

Luckily the Bluefly also sports a GPS and works through a serial port, so I’ve yanked off the Adafruit GPS breakout board and bodged the wires to insert the Bluefly in its place.
bfbodge
Then there was a small matter coding it up using a complex state machine to program the GPS module through the Bluefly pic processor to get it to read at 10 times a second.

But then the BNO055 orientation sensor played up and decides to shutdown at unexplained moments for unexplained periods of time.
badorient
The white vertical lines are 10 minute intervals, and there is a green dot for every successful orientation reading, with y-value proportional to the time since the previous reading, so I’m getting gaps in the data of half an hour in flight.

I’ve produced a reset timer to try and start it off again if no data comes through for 20 seconds.

Anyways, here is one of those nerve-wracking close encounters with the ground during the flight.
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Tuesday, April 19th, 2016 at 11:29 am - - Hang-glide

If you look closely you can see the grin behind the helmet.
DCIM100GOPROG0020178.
There was nothing especially epic about this XC flight from the Long Mynd to Clee Hill, except a masterful get-away from the slope in nil-wind with just one thermal during which I miraculously stayed on top of all the paragliders. Also there was a very low-save.

I took off at about 1:30 during the period when the wind was less than 5mph and sometimes coming from the SW. This trace is off the Long Mynd Gliding Club weather station:
myndwind

No one could explain why there was so little breeze to make reliable ridge soaring possible. Meanwhile, there were champion pilots flying 100s of miles on seven hour flights on that day, which one must try not to feel bad about, when I “only” managed to stay up for an hour and a half.

One thing I did learn for sure is that I utterly depend on the thermal assist of the XCSoar running on my android phone. (That Kobo kit you see in the video is going in the bin.) The magic went away when the phone ran out of batteries; my thermal tracking abilities went out the window from that moment on. So this flight (and hopefully many more, when I sort out an extra power supply brick for the phone) is dedicated to Lines 145 to 202 of XCSoar/src/Renderer/TrailRenderer.cpp which was able to direct my search for lift whenever I lost it. This is the section of the manual describing the critical feature:

xcsnailtrail

A couple more regrets. I didn’t make cloudbase by at least 300m, according to the dew point measurements. And the barometric reader, based on bit-bashing and interrupts, is completely shot to pieces by the overload on the microcontroller from acquiring so many other inputs of data. Only about 1% of the readings are getting through. I’ve got to come up with some other answer, and I don’t have a lot of time in a week when we’ve got some help doing something about the state of the kitchen floor.
kitchenhole

Wednesday, April 13th, 2016 at 12:39 pm - - Hang-glide

Thought I’d scan and upload my article about flying in Austria for folks to download:

JGTskywingsLoser.PDF (7Mb)

Individual pages:

JGTskywingsLoser_p1

JGTskywingsLoser_p2

JGTskywingsLoser_p3

Tuesday, March 29th, 2016 at 9:28 am - - Flightlogger, Hang-glide

It happened towards the end of the flight before last when my wings became my own, and I just wasn’t thinking about it any more. I stopped having those intervals where I lose concentration and fall out of the sky because there was no concentration to lose. It was all about the feeling.

teba1
Above the town of Teba watching the cars scooting along the grid of streets like busy beetles in a rotten log

teba2
Low on same rocky hill just after take-off where I struggled to survive for some minutes before I found a bubble of rising air

If you need to learn hang-glide, there’s a English school down here called Lejair where you could get it all done in two weeks (instead of the average two years of weekends back in England) because the weather is better and they use tow trucks with gliders tethered above a trailer so you can learn how to fly it without having to run up and down the hill and learn how to steer in short difficult bursts. (If you have to ask why you need to learn hang-gliding, then you don’t need to.)

birdscage
We were woken by all this nice birdsound. Then we spotted that it was from three tiny birdcages in the courtyard below and it seemed so cruel. Why can’t they use little speakers tuned to a radio channel that broadcasts live birdsound?

Got to go now. We’ve not had an off-day where I can devote 10 straight hours to coding the datalogger analysis or write any of it up. I have two interesting results to report. One being the delay on the GPS, and the second being the clean mathematical relationship between the turning circle and bank angle as measure.

Wednesday, March 23rd, 2016 at 11:19 am - - Kayak Dive

I really have been neglecting to blog. I’m going to bang out a few quick posts on this the day before my holiday.

Saturday 12 March involved a grumpy day paddling around Hilbre Island with a rather fuzzy camera.

This is the stone wall on the northwest corner of the island at high water:

The professor on the water had just gone on a 10 day trip to Japan to use up an academic travel budget, and at the same time busted a chunk out of the dwindling global carbon budget [podcast here]. You don’t want to see what the bailiffs do when they collect on an unpaid carbon debt. They’ll take your food.

I’ve been speculating about a specialization of my Question from Hell proposal where visiting professors who have just flown to give a lecture get routinely asked about their carbon budget (which they could have avoided by teleconferencing) as the first audience question from a young student. It will be rude and ungrateful to ask such questions of a visiting guest, and will embarrass everybody. The excuses are lame.

The top excuse will be: “We don’t have the equipment”.

If that one gets a lot of laughter, the second excuse will be: “Meeting in person makes a big difference”. To which I’d like to respond: “Where’s the research?”

There isn’t any.

I’d love to set up a controlled experiment where the person who doesn’t do the 10 day trip to Japan gets to take a 24 hour bus ride to a hotel opposite a Japanese takeaway in Dundee via Plymouth and is locked-in with the internet where his only communications portal for the next 120 hours is a telepresence robot parked in the corner of the lab in Japan. He is free to rove the corridors if he’s being ignored. Maybe one of the brighter students would take pity on the robot and take it home overnight for late night chat with bottle of sake, or even for a night tour round the city on a motorbike. I hear these VR goggles and hi-def cameras are pretty good these days.

The time duration exposure, the portability, and the lessening of inhibitions could easily mean that human bonds and interaction could be much enhanced compared to proceeding to these places as a meat embodiment that smells and needs to go to the toilet occasionally.

If this Questioning takes off I am expecting that university administrators, who can be blindingly stupid, commit to ban such questions, as you cannot ban something like this without actually telling people what it is you are banning.

PS. Cory Doctorow was burning up the planet ten years ago.

Wednesday, February 24th, 2016 at 9:59 am - - Hang-glide

Work interrupted by a couple of mid-week trips, first to Long Mynd:

Then to Llangollen, where I didn’t fly so well and spent the entire time getting buzzed by this huge dual hang-glider that seemed always able to keep up with me.
llanfeb
That’s why you’re supposed to learn a lot by flying with really good pilots so you can see exactly why you’re not anything special at any time.

And anyway, the data logger was bust with a loose wire on the I2C connection. I should have enough data from the Long Mynd flight that I ought to be doing stuff with this morning. Instead I’ll probably work on the serial connection to the orientation sensor or do some on-line shopping for other electronic gadgets whose data streams I record and ignore.

Record and ignore

Remember the rule: the further removed in time and place is the data, the lower its value. While some data becomes relevant when it gets old, it’s as rare as antique furniture. You can count on the crap rotting in your garage not being within that category. The conclusion is if you don’t find an application for the data now, you’re not going to find it later on.

Tuesday, February 16th, 2016 at 6:30 pm - - Flightlogger, Hang-glide

Following a very grumpy Friday and an off-the-cuff comment by someone on Facebook to the Wrynose Pass as a potential easterly site, I headed off from Bull Pot Farm into the Lake District where I have never been before.

I was not in the most ideal mood for this sort of thing, being alone with a hang-glider on an unfamiliar craggy hill at 3degreesC and 27mph wind. Fortunately I stopped myself from doing anything really stupid, and sat in the car stewing and programming until suddenly and unexpectedly the wind dropped to something between too light and perfect.

I didn’t hang around, having already scouted for my hillock of a take-off point.

snaptakeoff
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Monday, October 5th, 2015 at 7:18 pm - - Kayak Dive

Not much bloggable recently. Some well-formed untested ideas on matters of servo motor control, and lots of bad psychology. Two discoveries of note that’ll take up a lot of time are jscut for CAM and chilipeppr for CNC downloads, both of which run in the browser. I have an interest in this approach, but now that I’ve found some people who are doing it effectively, it will save me a lot of time.

Meantime, here’s a couple of bad pictures from a cheeky kayak dive in the docks during Becka’s Thursday night canoe polo session (aka murderball).

Getting ready to go down:
eel1

One of the scary eels that made me shriek when it appeared in the dark.
eel2

Eels look and move a lot like snakes. We’ve got an instinctive fear when we encounter them in their own environment. It was interesting how they could swim backwards just as easily as forwards.

Monday, September 7th, 2015 at 10:55 am - - Kayak Dive

Home at last. Lots of stuff to do, so here’s just the bare facts of the trip to the north part of Ireland with our kayaks, as well as a 4-day booking with aquaholics where the weather blew northerly gales the whole time, which denied access to the famous north face of Rathlin Island and the basking sharks were a no-show.

Date Site Place type depth (m) time (mins)
2015-08-28 Mulroy Bay Downings Kayak 15 19
2015-08-28 Mulroy Bay Downings Kayak 17 35
2015-08-29 Melmore Head Downings Kayak 20 45
2015-08-30 Gloster Rock Malin Beg Kayak 20 12
2015-08-30 Shark Rock Malin Beg Kayak 20 30
2015-08-31 2nd Pinnacle Slieve League Kayak 18 12
2015-08-31 Big Cave Slieve League Kayak 9 15
2015-08-31 Carrigan Head Slieve League Kayak 20 23
2015-09-01 Portnagh Rock St Johns Point Shore 26 52
2015-09-01 Skuddagh Rock St Johns Point Shore 17 48
2015-09-02 Black rocks Rahlin Island Boat 31 36
2015-09-02 HMS Drake Rahlin Island Boat 18 46
2015-09-03 Black rocks Rahlin Island Boat 31 38
2015-09-03 Scallop bed Rahlin Island Boat 21 48
2015-09-04 SS Lough Garry Rahlin Island Boat 30 29
2015-09-04 Harbour wreck Ballycastle Boat 19 37
2015-09-05 SS Lough Garry Rahlin Island Boat 29 29
2015-09-05 Black rocks Rahlin Island Boat 29 36
2015-09-06 Lees Inner Wreck Strangford Lough Kayak 11 24
2015-09-06 Lees Outer Wreck Strangford Lough Kayak 12 29

Kayak diving wins again!

The most notable sighting of wildlife was this unexplained swimming snail above the kelp at the start of yet another black rocks dive (where we failed to find the right bit as usual).