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2015/05/23 Diving a Cenotes and Cozumel with Arturo
π 2015-05-23 00:00 in Diving
I was going to Japan at the end of May, but Arturo who was travelling in Cuba made us an offer to join him in Mexico to go dive around Cozumel, and get back just in time for my flight to Japan. Since I had never been to Mexico to dive or otherwise, and Jennifer only once a long long time ago, before she was certified, we accepted and joined him there.

The first day, we went to dive in a Cenote (underground river system), which was a bit colder (24C), mostly devoid of aquatic life (it was fresh water, not salt water), but the cave formations were interesting to dive.
A few pictures from the Cenotes:







We then took a ferry to Cozumel, where we did a combination of boat dives (2 every morning, some in the afternoon), and shore dives which actually were quite good considering, especially if you enjoy fishies in training like Jennifer likes to say:


fish like to hunt in pair with rays
fish like to hunt in pair with rays

so many lobsters, everywhere...
so many lobsters, everywhere...



The wreck dive was interesting:




My heart will go on... :)
My heart will go on... :)




Nice fishies in training by the jetty for a dusk/night dive:

those baby rays were being 'friendly' :)
those baby rays were being 'friendly' :)






More boat diving:







they had very nice sea horses
they had very nice sea horses










The night dive we did from the boat was particularly good. Octopus coming out to hunt, giant crabs, lobster, and more:






The next morning, I got up at 05:00 to do a night/sunrise dive by the jetty and it wasn't half bad either :)



this shrimp was suicidal in my opinon :)
this shrimp was suicidal in my opinon :)


We then had time for 2 more boat dives before being done for the day:







A few vidoes I got by the Jetty: An octopus hunting at night:

Eel/snake feeding:

Octopus feeding by the jetty at night:

Baby ray, those things are so cute:

Now a few videos from the boat dives. We saw many turtles, including this turtle eating:

They also had those shrimp crabs everywhere. This one was busy eating:

There were lobsters everywhere. We saw those two lobsters 'talking':

This lobster was out hunting at night:

A big crab out hunting:

And a big octopus hunting:

And that was it for diving in Cozumel. The water was super nice, great vis, temps in the 29-30C range, not too much current, and actually pretty good critters to see. Thanks to Arturo for getting us there :)

2015/05/23 Some Time in Playa Del Carmel and Cozumel with Arturo
π 2015-05-23 00:00 in Trips
Arturo was flying through Mexico on his trip back from Cuba, and he figured he'd go do some diving in Cozumel on his way back, and invited us to join him, so we did :)


where we spent our first night, noisy due to partying and music on the beach
where we spent our first night, noisy due to partying and music on the beach

Arturo and Peter, waiting for us to arrive
Arturo and Peter, waiting for us to arrive


The main street had a bit of 'everything':

no prescription? no problem :)
no prescription? no problem :)


very classy T-shirts.
very classy T-shirts.

The next morning, we took a guided tour to a Cenote (underground river system) to go diving there:



Diving can be found on this page.

After our 2 dives, we took the ferry to Cozumel:






working hard, or hardly working? :)
working hard, or hardly working? :)

One evening, we had a mexican party, including a pinata:


Jennifer had a shot
Jennifer had a shot

and she won a hat
and she won a hat

Lots of cruise ships:




One afternoon, since we didn't have any dives, we went to the nearby dolphinaris:















At the end, they had a dolphin tow us across the pool. I hope it didn't mind too much:



you do get water in your nose though :)
you do get water in your nose though :)

Nice sunsets:


after sunset, it was a good time to night dives by the peer
after sunset, it was a good time to night dives by the peer



After our last dives, we went back to the mainland for a private tour to Chichen Itza:


Grr! :)
Grr! :)













rain wasn't much of a prolem, but the blazing sun was :)
rain wasn't much of a prolem, but the blazing sun was :)

Many street vendors:




Also got to see some iguanas:



On the way out, we went to see a couple of Cenotes:




A big thank you to Arturo for organizing everything.

2015/05/20 5 Miles of Thunderhill with TS
π 2015-05-20 00:00 in Cars
Since I have been melting my brake sensors on my car and using up my tires and brakes too much, McLaren nicely decided to send one of their coaches and a technician with me at my last Thunderhill track day. Greg, the coach, was there to try and get me to be nicer on the brakes, and Johan, the tech guy, made sure my tires were not overflated so that they would last longer (so far I have been running them in the 34-37 range, short of being told anything else when I asked, and turns out I had to run them 28-31 range instead.

Like previous time, this private track day had great cars, pictures are worth a thousand words:


Hi Attila, nice plate!
Hi Attila, nice plate!









So, my coach Greg did a great job of quickly figuring out that I was overworking the brakes by just being on maximal brake pressure for too long. I know about releasing brakes and finishing with a light trail braking to reach the apex (add steering while releasing brakes), but in a straight line, for maximum braking, I was using maximum pressure for 3 seconds or more if need be.
He pointed out that I should get off maximum pressure as soon as start braking, and taper off pressure as the car slows down, even if I might still be doing over 100mph at the time.

For now, I'm slower on laptimes doing this because it's harder to keep optimal pressure and just braking a different way from the easy "full on brakes" I've been done for many years, but I believe him if he tells me that the car can stop as fast or faster, if I modulate pressure from the beginning and start easying off the brakes right away, not later just before I'm about to turn.

In the morning, we drove way below normal speed so that I could try and practise the braking, but I found it hard to odd because the speeds were not realistic and I just couldn't force myself to brake well when I was going too slowly.
He then got off the car to let me try on my own but I only got 2 laps before the track was shut down before lunch. Still, I got a 3:33:85, which was 8 seconds faster than his lap, because I kind of quickly reverted to the full force braking I've done for so long (thunderhill 5 mile track with cyclone). Sad thing is that I got that best time of the day without having a great line everywhere because I don't know the west track well (that was my 3rd time on it).

He then confirmed that I obviously had gone hard in braking and the corners, and I had lunch to try and drill in my head to try harder to apply what he had been telling me.
The next session, I slowly did better trying to apply what he was saying and trying to ease off the brakes. I was a lot slower, but that was expected.

While reviewing the video and data recording, Greg pointed a few places where I wasn't braking right, some minor line suggestions, some were definitely better, and others were maybe about the same, but worth trying.
My 2nd and last session on my own, I started with a wet track and worked my way up slowly as it dried, and got back up to a 3:35. That was with better lines and not doing some mistakes on the west track that I did in the morning on my faster lap.

So, clearly I haven't yet matched my speed driving the aggressive (but strangely controlled, because I've been doing it for too many years) way, but hopefully I can work my way back up to it without being as hard on the car.
I'm not really disappointed there, I have 15 years of practise driving the way I do, so I didn't expect to match my times driving a new way in just 2 sessions at speed.

What this all means is that I will have do try this a few more times to see how I do, and measure resulting brake wear and see if Dan tells me "eh, I've never seen that color on metal before, and we've just ordered another set of wear sensors because the other ones were nowhere to be found" :)

I'll now have to go back to see how I do with more practise. Also, because this was the 5 mile track, I have no idea how fast 3:33:85 is, or how much faster I could have gone with more laps at full speed with maximal braking. So, I'll know more next time(s).

The flight home was somewhat interesting, rain in the surroundings, low clouds, but I was still able to sneak below the cloud lawyer and get in to Palo Alto:




See more images for 5 Miles of Thunderhill with TS
2015/05/17 Cularis 7 Channel Glider With Crow Flaps and Washout Taranis Config EEPE
π 2015-05-17 00:00 in Rc
The Frsky Taranis is a great transmitter, but it can be a tough to program when you're learning:


So after many hours of making a very custom 7 channel config for my Multiplex Cularis FPV Glider, with differential flaps, crow flaps, aileron washout for tip stall avoidance, and switches to control my FPV camera and talk to APM::Plane, the autopilot running on my pixhawk, I've published my setup with explanations so that others can use it.


Again, here's a link if yould like to read about my Multiplex Cularis FPV Glider Build.

You will need sounds to install on your Taranis in SOUNDS/ subdirectory on the sdcard:

  • sounds (it's a complete collection, more than the ones I use, but you should find them useful)
  • Here is my EEPE config file for companion to load the config into OpenTX:

  • Cularis EEPE
  • Last, but not least, you will want to read this document that explains how it all works:
    https://docs.google.com/document/d/1bGKjyvOksHBhD8gT3Q20ZmDu1TUsDn15BvGPHw-doVg/edit
    You can also download (a maybe slightly out of date) PDF:

  • Cularis_Taranis Setup PDF
  • 2015/05/16 Another Maker Faire
    π 2015-05-16 00:00 in Public
    Mmmh, I didn't read my own blog post from 2 years ago saying that going both days was overkill and unnecessary. I stretched the time by going to some talks Saturday and Sunday, and that was kind of a mistake as more than half the talks were not worth the time at all, and some were a total waste of time. Maker Faire really needs to improve their talks by giving full description, vetting speakers, and ensuring proper content, or people will know that talks are mostly not worth it.

    But the rest was still worth seeing, and I enjoyed it. Big stuff outdoors:







    backyard roller coaster, very nice
    backyard roller coaster, very nice

    Indoors:

    very cool, you can now draw circuits with a silver pen
    very cool, you can now draw circuits with a silver pen

    food 3D printing, brilliant!
    food 3D printing, brilliant!


    very very nice hack
    very very nice hack


    big and small robots :)
    big and small robots :)



    the drawings were made with balls run with a magnet underneath
    the drawings were made with balls run with a magnet underneath




    They had a battle of the drones which really was quadcopter fighting (knocking the other guy out of the air):


    One worthwhile talk was a status update on arduino, from its creator:


    another talk from Atmel on arduino debugwire was very interesting too
    another talk from Atmel on arduino debugwire was very interesting too


    Google was showing off its original VTOL package delivery plane:


    RC plane used for city imaging
    RC plane used for city imaging

    robot wielding a knife between a hand's fingers
    robot wielding a knife between a hand's fingers

    Anyway, I was mostly done by saturday evening. I went back sunday to see a few things I could have seen if I hadn't gone to some talks Saturday, and then called it a day.

    See more images for Another Maker Faire
    2015/05/05 My talk on using Docker to Containerize Existing Applications on an Existing OS Install
    π 2015-05-05 00:00 in Linux


    Summary: how to use docker in ways it was never meant to be used, namely to containerize already installed applications on your host system without needing a separate server image just for the container, and a new install of your app in that container.

    Full talk description: Container solutions like docker were designed to let you run an application on a vanilla OS image. This is great if you want to totally decouple a new application from the underlying OS. This is not great if you don't want to have to maintain 2 operating systems (the host one and the container one) if you already have well customized OS, and if you simply want to run some existing applications in a container. This gives you the security benefit from resource/disk/network separation between untrusted applications and the rest of your operating system without having to start from scratch with a base OS and lots duplicate packages between the container and the host OS. More importantly this lets you switch existing working applications to a state where half their functionality (like the web facing portion with untrusted php code) runs in a read only container, while the backend that needs access to local disk and network resources, run outside the container, and post the data to a filesystem that is only read only in the container but sufficient for serving results.

    You also benefit from completely controlling the container image and not relying on an image retrieved from the internet that may not be trustworthy by reusing the exact same OS image inside and outside the container, also minimizing upgrade time and cost.

    My talk will show how to use docker to achieve those goals and get a chance to containerize applications that you probably wouldn't get around to run in containers otherwise.

    Video:

    Slides which you can read:

    2015/05/03 Linuxcon JP 2015 in Tokyo
    π 2015-05-03 00:00 in Linux
    I was thankful to be invited at Linuxcon JP again to speak, this time about using Docker in ways it was never meant to be used :)

    A few pictures from the event:






    use of linux at Facebook by Chris Mason
    use of linux at Facebook by Chris Mason

    The new aria android phone with swappable modules
    The new aria android phone with swappable modules

    nice snacks for attendee reception
    nice snacks for attendee reception

    and just like this, it was over, and time go depart until next time.
    and just like this, it was over, and time go depart until next time.

    Thanks all, see you next year hopefully.

    See more images for Linuxcon JP 2015 in Tokyo

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