Monday, August 25th, 2014 at 1:53 pm - - Canyon, Cave, Hang-glide

I did get a very short canyon trip with an even shorter rope before expo was finished.


The canyon was called Salza Stauseeabfluss, and it went from the dam on the lake from Grimming. The rope was labeled at 80m, but no one had noticed it had been cut at 36m when they picked it up. We had to descend down the wall of the canyon in three stages off trees. We also got the walk out spectacularly wrong, and ended up clawing our way up a 60degree grassy slope in the dark.

This was on the same day I had a very nice 3 hour flight off Loser totally alone (due to west wind predicted) with a relatively low cloud base again, and tactically squeaked through the pass into the Bad Mitterndorf valley knowing that there was a good landing field there which I had used a week earlier.


Unfortunately every single field including this one seemed to be full of tractors cutting and bailing hay. Fortunately, a bird appeared and showed the way up to the clouds after 15 minutes of barely maintaining height.

That’s one of the lessons from the 50k Or Bust Book: both time and place matters. Use your arithmetic to know that a slow descent rate of 0.2m/s is only 12m a minute (or 120m in ten minutes), which means you can stay in the game for long enough for the next thermal to rise.

Because the clouds were low, I didn’t want to stray up into the mountains, and stayed close to the valley where the lift was scratchy. The predicted winds were never materialized and I belly flopped on my landing again.


Here I am looking to the Grimming. If conditions this year had been equal to last year I would have got beyond it into the Enns Valley and maybe around to the Dachstein. This is the big target.

The annoying thing about flying is how quickly a good flight wears off on you. I was already fidgeting the next morning as though I had achieved nothing the day before.

Becka said something very mean to me last night: “You seem a lot more dissatisfied with life since you took up hang-gliding again.”

This needs sorting out. My original notion had to be to treat hang-gliding like skiing, where you go abroad on holiday to the appropriate place and do as much of it as you can to get it out of your system, and then come home and get on with normal life. But it’s not quite working out like that.

The final flight in Austria was in rough conditions and didn’t go anywhere, but the landing was perfect, like I was on autopilot.


Then the weather became rainy and normal for Austria, and we were into the depressing phase of bringing things down the hill and tidying up after expo.

We got away from the campsite at 5am in the drizzle and caught the 10pm Dunkirk ferry to Dover, although I did insist we stopped at the McDonalds in Zweibrucken because that’s where the previous car stranded me for two days in May.


It was the highlight of the journey.

Saturday, August 16th, 2014 at 7:25 am - - Adaptive, Cave, Hang-glide

It rains and rains and just won’t stop. It’s also gotten pretty cold and I’m having to wear all my clothes that aren’t damp from lying in the tent. The last day of warm sunshine was six days ago where I stood on takeoff for 2 hours as paragliders wafted past and went down in the totally dead air of that day.
See the smile? I want more flying. Some canyoning would be good too, but it ain’t going to happen on this trip.

When I finally took off I flew in a direct straight line across the valley beyond the highway and golf course, and then had to walk 5 miles back via an ice cream stand to Base Camp for a lift back up the hill, after which I drove down, fetched my glider, and drove back up again for the walk up to Top Camp (the Stone Bridge).
Here’s the outside view of Top Camp:
And this is the inside:
It’s both a rock and a hard place with nothing in between, but it is still better than tents because it is larger, cavernous, and not like a box of damp fabric that progressively rots things as each day passes.

I dropped into the far end of Tunnockshacht down to the new connection to Arctic Angle. Becka was away with the Austrians on a different expedition and couldn’t warn me that it was going to be an unutterably deep one. That wasn’t the problem. The problem was getting terrifyingly stuck in a U-bend crawl while weaseling around the C-leads waiting for the guy with the drill to rig a rope traverse along a ledge of an undescended shaft to access the phreatic continuation. Then we surveyed about 100m until it crapped out, and hauled ourselves back out by 2am.

I forgot to take any pics, so here’s a photo of a nosy horse’s nose:
On Tuesday I went to the newly discovered Balconyhohle. (The horizontal entrance is from a ledge within the side of a hole.) I was cold and had to keep eating. We killed a couple of going leads there too, but there’s enough unexplored ways on to keep this one spreading further underground. This has been the big find of the expedition. It’s a lot of work to keep up with the mapping.

Here’s a picture from the walk back to the carpark from Top Camp in the morning:

Since then I’ve been working on the Adaptive Clearing stay-down linking killing the bugs one at a time while all my HSMWorks buddies have been at a big planning meeting in Copenhagen this week. It seems like an endless grind. Anyway, I don’t plan to go there again, and the ferry between the UK and Denmark is being terminated this September.

One of the things that crashes the system is when the A-star linking can’t find a way to connect from point A to point B, and spreads out through every single cell in the dense weave until it runs out of memory.

One obvious solution is to generate a weave that has a wider cell spacing and solve the routing issue in it, but this is too complicated. I worked out another way, which is to deny it access to most of the interior cells of the fine weave that are nowhere near the boundary or on the theoretical direct line route. The A-star algorithm is so powerful that it will find a way round, even though the domain would look so much more complicated. This initial result becomes the starting solution for the linking path, on which the PullChainTight() function is called. This is actually a bad name for it. It should be called RepeatedlySpliceStraighterSectionsIn(), but this discription wouldn’t remotely be so compelling to the imagination.

This will get implemented only if absolutely necessary. The thing about the linking routine is that it does not need to work 100% of the time, because it can always fall back to the old way of retract linking, which is what everybody puts up with right now, so it might not be worth expending too much effort for the last 2% of awkward cases where the reliability is going to be questionable anyway. In software development the trick is to know when to stop.

Time to work on some cave surveying software today. Maybe I’ll get a flight in tomorrow. Hope so.

Sunday, July 6th, 2014 at 3:18 pm - - Cave

The Tour de France did their first stage through Yorkshire, crossing Buttertubs north of Hawes. This is quite a long way from Bull Pot Farm where we stayed, so I got a lift most of the way out and completely failed to find Becka and the others on the hill. (Luckily, I was carrying the lunch.) Who knew there would be such an incredible crowd and no phone signal on such a bleak moor? It was more packed than the Col d’Aubisque when we saw the Tour three years ago.

The ridiculous caravan was the same, albeit shorter and with not so many freebies being chucked out. You got to admire that corporate consumer product sculpture that gets paraded all up and down the countryside.

It was a really biting cold wind in the open. At least it blew the midges away. Take your pick. It’s a bad year for midges.

The leader Jens Voigt came through much earlier than the pack, ten minutes after an unexplained flyby of four helicopters.
This was further up the hill from the real packed crowd on the steep bit where there was barely any room for the riders to squeeze through.

Then it was time to clear the hillside. It became apparent that every man and woman that owned a fancy bike anywhere in a 200 mile radius was on that road trying to get off at the same time. All the cyclist spectators overtook me on the road back to Ingleton in a steady stream, because I’m really quite slow. There were no other cycles on the stretch back to the farm: just me. Some DVDs of the live race had been burned and driven up the track by the time I got there, so we could watch the whole race and all the stuff we’d missed while we had our tea.

Apparently that’s the real way to do it: sit in a cafe or pub on the route watching the live race on the TV, then step outside for the split second it goes past in real life, then get back in and carry on watching on the screen while you enjoy your beverages in the warmth.

Monday, June 16th, 2014 at 10:33 am - - Cave

What’s been going on since I got back from Austria? Mostly working (for a change), washing up, catching up on stuff.

After 18 months of agitation, I organized a Simultaneous Satellite Tech Summit in AD and managed to get 3 other people to turn up. The Tech Summit is a single 2-day conference between lots of the AD developers that takes place once a year in a hotel where everyone is flown in on expenses. Many of the talks are streamed on-line, so I thought it was a pretty obvious idea to hold a group watching event between the developers in England who were not burning lots of carbon to cross the Atlantic. This enables us to meet and interact in our local halls as people claim they productively do when they go to the real Tech Summit. After all, it’s more useful to form collaborations between the offices in the same country because it costs hardly anything to move between them and work on joint stuff.

This proposal brought out all sorts of flimsy arguments against it about how face-to-face meetings are so much better for forming relationships that don’t take account of the fact that we are software developers. We’re quite good at working together when we can actually access the same source code, and it is often the case that when we do meet physically on a personal level we won’t like one another at all. Stop arguing, the managers said. It makes our ears hurt. But how are we supposed to change things without arguing? You’d think a company that employs so many computer programmers would have some sort of a handle on the psychology of computer programmers.

I am not going to comment on the ScraperWiki newsreader event I went to in London, because I don’t know what to say.


Anyways, that’s just work. At the weekend Becka decided that I should go caving down Newby Moss Pot on Ingleborough as it was one of the ones she had not yet done from her favourite book: Not for the Faint-Hearted: 50 harder caving trips in Yorkshire.

I can’t say I learnt my lesson, so much as I should say: suckered again! It’s just a midge-infested fleabag of a cave with tight squeezes that lead to nothing of interest. Against everyone’s recommendation, I did it in a wetsuit, which meant I fit through the tight bits a lot better than when I have rolls of PVC fabric around me hooking onto every bit of rock in those wormhole crawls.

That’s enough of that. While Becka went on a quick trip down Penyghent Pot, I did a cycle tour of some of the Dales Hang Gliding and Paragliding Club sites over some of the region’s steepest passes.

I got everything from my waist down saturated with water walking up Cow Close Fell. I’m not sure any hang-gliders fly there due to the carry up and the bottom landing field in the valley being embarrassingly small. It looks like it would be harder work than Whernside. Whernside takes a SE-E, and Cow takes NNE-NE.


The other site I checked was Hawkswick which takes SW. This has a good track you could push a hand-truck up to the top and a good clean steep face to soar on.

I got tired of pushing my bike up the track and left it partly hidden in the bracken on the left. When I got back it was gone! Along with all my valuables in the pannier. That was a bad moment. I found it parked against the wall down by the main road. Not helpful.

I had no cream teas on the entire ride as there were none on the route. Becka and the others were already in the pub when I got back to the car in Horton.

Tuesday, May 13th, 2014 at 7:54 am - - Cave

I got tricked into going on my second caving trip of the year. Some friends visiting Snowdonia requested a caving trip nearby, and then got lazy and pulled out after Becka, one of her friends from up north, and a couple of other cavers wishing to inspect some new dig sites were already up for it. These digs are beyond the dig we had dug in ODB for 3 years before it broke through last year into a previously known cave beyond a rarely dived sump.

There were two parallel new digs, both good, with drafts detected by watching the smoke from a stinky joss stick. You could hear voices ahead of you from the other one when you had crawled to the far end of each one, so they were connected, although the draft was not circular. The dig I worked at was wide, up a 30 degree slope and full of slightly damp mud and boulders.

Excavating each boulder out and rolling it down the slope was satisfying and freed up a surprising amount of space.

That was Saturday. Sunday was windy and noisy about the house. Becka went to the science museum in Manchester. I should go to Manchester more often. I delivered some election leaflets and then went to bed, feeling that I had caught a nasty cold just in time for my holidays. Turned out it was probably a lack of sleep. The four hour kite surfing lesson that suddenly popped into the schedule on Monday turned out fine.

Hey, it’s more fun than piano lessons. We should all take lessons in a variety of things that are economically useless and we’re never going to be good at.

It was light winds, which was good for the confidence, even though the instructor said it was not great for making progress. Still, it was pretty magical to be out there in shallow murky water with the Liverpool skyline on the horizon and the wind turbines not spinning. I do feel these homemade wetsuits are a bit on the chilly side. I actually hate buying gear, so we’ll make do.

Tuesday, April 8th, 2014 at 9:56 am - - Cave

Weather was nasty over the weekend, I’m losing the plot when it comes to programming, and I enjoyed the physical activity I did last weekend, even though the flying was not successful.

I joined Becka and others on a “promising” dig in Gaping Gill beyond Hensler’s endless flat out crawls, and through the “blowhole”.

The dig was a tight wet inlet with pooling water, mud, and not enough room to turn over onto your back from your front. Clearly this had been subject to terminal worm-holing. There were a lot of digging tools to use with which I tried to widen the passage vertically at the front — though I didn’t pass much spoil back into the digging trays during the process. Tom took over after 90 minutes of me hogging the dig until he got too cold due to not wearing enough neoprene. We retreated and warmed ourselves up by chucking a heavy rock back and forth between us until our lower backs hurt. The remaining diggers complained that we’d used up all the air, so they couldn’t do any more. Never a good sign that a dig is heading towards big passages.

I got back-of-the-knees wetsuit rash walking up to the entrance, and we nearly got lost in the fog on the walk down. It was great. After a quiet night at Bull Pot Farm (all members were at the dinner/AGM), I got dumped at Clive’s house for a few hours while Becka went caving. This lead me wasting time on a couple of FOI requests to [1], [2], and flicking through the ACCU magazine to find an article about the First International Conference on Software Archaeology.

About time people started talking about software archaeology. It’s evidence of the dereliction of responsibility that the executives running our large moneyed software companies whose wealth depends on the functioning of decades old piles of buried and very crappy code are not properly funding this field of study, and leaving it up to a small number of visionary amateurs to do what little they can, while the executives cash out their share-options for yachts and corporate take-overs. I see no process within the corporate power structures that would result in those who control the money becoming aware of where the actual needs for investment lie. If it was seen that corporations devolved certain budgets to be disbursed by internal committees staffed by people who understood the challenges and were in a position that they did not need to get things signed off by senior officers who didn’t understand the challenges, maybe something positive would come out of it. After all, the public sphere exists as a system of quasi-autonomous organizations with their own budgets to get on with matters that central government are not always politically happy with, but which need to get done, so why is it not a viable option to consider such formal systems of operation within corporations?

Saturday, November 30th, 2013 at 2:56 pm - - Cave

Short note on the previous weekend. There was a meeting at Andy Eavis’s house under the Humber Bridge following their great cave chamber laser scanning projects in China over the summer. Somehow I got invited, probably because I say I can able to do things with CADCAM software, and such forth.

We cycled from Brough behind the BAe factory where they make the Hawk “Trainer” jets. Funny how there’s so many “Trainer” jets being exported. What a laugh. Doesn’t do any harm. They’re not “weapons”. Like those “replica” hand-guns with a complete set of working parts. Or a presidential candidate who says that he smoked, but did not inhale. Far too few people laugh at these official lies to stop them sticking.

Andy is the current president of the International Union of Speleology, an off-shoot of the International Congress of Speology, the 16th of which I went to in Brno this summer in the Czech Republic. It’s a fantastic bureaucracy, worthy of Kafka, where Andy is named as the coordinator of the Long, Deep and Large Caves Commission, among about a hundred other commissions.

Of course, none of the commissions is in charge of new technology that would be game-changing for cave surveying. Nor do they have anyone who is particularly interested in cave survey software (at the Congress, we had to have our meeting in a cafe round the back). If I was in charge I’d establish a Commission on the Relevance of Commissions and do some long-overdue weeding.

Anyways, we got to see some of the point clouds being rendered by the experts using the open source Cloud Compare software. As standard practice, the point cloud was thinned to make it renderable.

Someone there need to produce a video of a flythrough and wanted to use all the points, and didn’t know how as the expensive software they used crashed when it received more than 10 million points. What crappy software engineering. I worked with him on a work-around.

I haven’t had time yet to download and install Autodesk ReCap to see if it is up to the job. Probably not. We’re getting hit with trillions of laser scanner points now, and no one with a budget is taking it seriously in the software world yet. (I do, but I don’t have a budget, do I?)

Quite coincidentally, someone sent this youtube video about a company called Euclideon claiming to be able render unlimited point clouds at a reasonable frame-rate using just the CPU. It’s a great little video. I’ve watched all of it twice.

There’s been a lot of controversy around the claim, which is not surprising for something that’s been worked on for seven years without releasing a product.

I think I may have worked out what’s going on here, after a long sleepless night. If I have it right, the technique does not allow you to zoom; you can only move nearer or further from the view.

I don’t need any more distractions. Maybe I’ll toy with an implementation once we do start getting our own cave scans to play with.

Monday, September 23rd, 2013 at 2:27 pm - - Cave 7 Comments »

I just spent a grey sky weekend down in Bristol investigating the cave surveying technology potential of this Hokuyo UTM-30LX-EW, that I bought with my much diminished pocket money.

I bought this one, as opposed to the slightly cheaper UTM-30LX that most robot research teams go for, because it is IP67 rated, as opposed to IP64. The IP Code says the first 6 means “Dust tight”, and second digit 7 means protected against “Immersion up to 1m” rather than 4, protected against “splashing of water”.

I know what caves are like.


Sunday, August 11th, 2013 at 8:09 am - - Canyon, Cave, Hang-glide

Expo is small this year. Everyone is up the hill, except for me and Becka, and Becka isn’t with me at base camp because she has disappeared to a different caving expedition run by Austrians for the week. The weather has reverted to type, with several days of rain.

I’ve been working and programming for a change and my eyes are sore. A recap of some things.

In the last week of July when it was perfect flying weather I was at the 16th International Congress of Speleology in Brno.

It happens every four years and was a little too proto-scientific for me. I followed up every talk that had to do with data loggers and temperature sensors, and the general message is that nobody really knows what to do with the data. In particular, the Hoffman institute who collects lots of lovely data, and then stuffs it all into an excel spreadsheet with no idea what to do with it later.

In spite of the attendance by all the major contributors to the field, there was no scheduled workshop on cave surveying software. (Software is not real science, see?) So we had to invent one in a cafe at short notice.

Becka had a go at the speleo-oplympics and got scars from the chest tape on the 100m prussick (done in a T-shirt). Unfortunately it wasn’t a fair fight because a couple of Russian ladies who took this sort of thing a lot more seriously and probably trained throughout the year came along and cleaned up. People came out to see them race through the SRT obstacle course, which they did many times to get it right.

Then we got to expo. We’ve had the mid-expedition dinner. Got a visit from the deputy mayor of Bad Aussee for our 30th year of squatting in the same campsite every summer.

Yesterday we went canyonning in Strubklamm. Seems you can do a canyon too many times. I knew every corner off by heart. The jumps were good, although they didn’t seem to require the usual amount of dithering, standing on the edge, Will I? Won’t I? When do I go?

There’s kind of a decision-making protocol happening in your brain, with one part holding you back because it’s a silly pointless dangerous thing to do, and one part that eventually has the guts to over-ride it.

It’s like that with the hang-gliding. Except you can get sufficiently focussed on waiting for the moment when the wind is right that your guts are tricked into missing the moment. It needs to throw its veto in at the exact instant when you could simply step back, and this requires accurate timing as to when you higher brain is minded to be about to do something ridiculous. If the trigger for the action is external rather than internal, then it’s a little more tricky for it know when to step in react. It gets there too late when you’re already off.

It is exquisite magic that you can become a speck in the beautiful sky. Of course, it does not look like that when you are up there, because all you see is the ground around you looking down. The realities of where you feel and where you are are quite different. You’re in another dimension.

Meanwhile, I’m working through yet another half-baked idea on 5-axis machining, after all the other ones have failed. I’m getting far enough away from the usual approach that something might work. I do know now that it should not be done by (a) drive surface projection or (b) contact point driving, so it’s all about finding the alternatives.

Friday, May 24th, 2013 at 9:26 am - - Cave

I have a confession to make. The digging trip in April wasn’t quite as boring as said.

In fact, we broke through. But since it would be about a month before the digging team could get back together and do all the stuff we needed to get done before the teeming hoards went in, we kept it secret.

To recap, the dig started in the dry mud floor in this terribly obvious place here: