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2018/05/29 EDM Party Shirt powered with FastLED::NeoMatrix and Adafruit::GFX, plus 160Wh (10Ah/4S) worth of lipos
π 2018-05-29 00:00 in Arduino, Clubbing, Electronics



After I figured that my previous shirt was getting a bit stale, I wanted to design EDM Party Shirt v2, which both had to be easier to wash (the previous one had LED strips all over it that were too much work to remove, making the shirt not really washable), and I also wanted it to be more special.
I had been playing with Adafruit::NeoMatrix and figured it would be cool to have a NeoMatrix on my shirt (also it would be easier to remove a whole panel to wash the shirt).

So, in the great tradition of yak shaving, I first decided that I should be able to use FastLED instead of Adafruit::Neopixel. This was mainly at the time because FastLED allows parallel output and therefore allows updating a screen by segmenting it in smaller pieces that are updated in parallel. With Adafruit::NeoMatrix, my 768 pixel panel would have taken about 30ms to refresh, or only 33 frames per second, which is not a lot. With FastLED, I was able to trivially segment it in 3 and get 10ms/100fps, which is a whole lot better for animations.
Turns out, switching to FastLED also gave me access to LEDMatrix, an alternate library which while lacking Adafruit::GFX primitives, offers another nice API including better text and basic sprite support.

So, I started a port of Adafruit::NeoMatrix to FastLED and wrote FastLED::NeoMatrix. It was actually a non trivial port, which took much longer than I thought, but I got it working in the end:


by then I was already able to display with 3 data lines, one for each 32x8 panel
by then I was already able to display with 3 data lines, one for each 32x8 panel

In the process, I managed to plug the wrong power into the panel and blew a pixel. Thankfully I was able to borrow another pixel from a strip and soldering it in place to fix it:


Once the port was done, came time to get the panels together. Wiring was a bit challenging because I had to ensure that power was injected at a mostly equal value in 9 different points (3 per panel) due to voltage sag at higher amps. I then quickly found out that with 3 data lines at high frequency, there is cross talk between the wires, so I switched to a CAT-5e cable where each data line is twisted with its ground and the remaining 2 wires are used to bring VCC (5V). Technically my 3 panels can use up to 60A at 5V at full power. Obviously many things will melt before that, and I'm using a power converter that tops out at 10A. Even 10A is too much for the wiring, but thankfully my displays don't use that much brightness (it would be blinding to people):


two 5Ah 16V lipos give about 160Wh, just enough to run 2 panels 10 to 12H
two 5Ah 16V lipos give about 160Wh, just enough to run 2 panels 10 to 12H

the fancy energy meter keeps track of how much time I used and how many Ah came out of the batteries. Useful to know how much time I have left. The blue meter is amps at 5V (after the power converter) and the red one amps at 16V (straight from the battery)
the fancy energy meter keeps track of how much time I used and how many Ah came out of the batteries. Useful to know how much time I have left. The blue meter is amps at 5V (after the power converter) and the red one amps at 16V (straight from the battery)

on the right, I have a backup ESP8266 if the main one fails, a backup BEC (5V converter) that's technically 10A capaable but not meant to do more than 5A continous, and bottom right is my older 3A BEC with in line amp meter
on the right, I have a backup ESP8266 if the main one fails, a backup BEC (5V converter) that's technically 10A capaable but not meant to do more than 5A continous, and bottom right is my older 3A BEC with in line amp meter

the new tobsun 5V converter is bulky but does 10A without issues
the new tobsun 5V converter is bulky but does 10A without issues

For the back of the shirt, I got some fabric and created an inside pocket to hold the panel:




it then mirrors the front
it then mirrors the front

All this crap goes into a fanny pack, and gets wired to my shirt, pants, and glasses:



the cool part is that my back also has a panel inside the shirt that uses the shirt as a diffuser
the cool part is that my back also has a panel inside the shirt that uses the shirt as a diffuser

You can get the code I wrote for the shirt here: https://github.com/marcmerlin/NeoMatrix-FastLED-IR

This video shows an early version of the code working on a desk:

This video shows the animations:

While this video shows the tech a bit more:

2018/05/19 A few awake hours in Vegas during EDC
π 2018-05-19 00:00 in Trips
This is probably the trip whwre I spent the least amount of time in Vegas. Between getting up around 14:00 and leaving for EDC around 18:00, that left for very little time.

I tried a new buffet:





Then time to go back to Bellagio to see their current displays:









Gordon Ramsay burger was a mistake, took 45mn+ to get the burger and it wasn't bad, but not that special either:



2018/05/18 Another EDC in Las Vegas
π 2018-05-18 00:00 in Clubbing
I can't believe it was already my 4th EDC. Time flies... Thankfully Insomniac moved it one month earlier this year, so it wasn't as damn hot as last year where some people actually died of dehydration, some apparently waiting in lines that were way too long in the hot sun :( I remember one night where it was 95F/35C all night and some stupid high temperature during the day.

This year, I got to beta test my new and improved Neopixel shirt, which is now a dual NeoMatrix shirt. Sadly, one of the 2 panels shorted by day #2 (build issue which I was only able to fix after getting home), so I was running in degraded mode with only the front panel for the last 2 days. Still, people loved the shirt :)





like pokemon, you gotta collect them all :)
like pokemon, you gotta collect them all :)

met some fellow Trance Family SF on day #3
met some fellow Trance Family SF on day #3

If you'd like see the different animations from the shirt, you can find them here:

I was able to try a very cool VR drumming game. It was very well done:


Now, I was not the only person to be shiny, which is one of the reasons I love EDC and Burning Man:




While I didn't find anyone who was able to put that many neopixels in their shirt (to be fair mine require non trivial amounts of power for something wearable). A few people had cool displays on poles with a big lead acid battery:

this one the only neopixel based one I found
this one the only neopixel based one I found

an interesting hat
an interesting hat

cool head gear
cool head gear

multiple pole based ones
multiple pole based ones

the 2nd fanciest ones I found were these, but based on a thick panel that requires constant refresh (also too thick to wear)
the 2nd fanciest ones I found were these, but based on a thick panel that requires constant refresh (also too thick to wear)

the pitch is much better though, allowing for better writing than I can do on mine
the pitch is much better though, allowing for better writing than I can do on mine

sadly the refresh rate is too poor for pictures
sadly the refresh rate is too poor for pictures

pretty nonetheless
pretty nonetheless

the fanciest pole was this one, with remotely addressable neomatrix text scrolling display
the fanciest pole was this one, with remotely addressable neomatrix text scrolling display

Good job Afik
Good job Afik

word!
word!

Other signs and people:


not the first time I saw this one, but still hilarious
not the first time I saw this one, but still hilarious




Now, you don't have to be an engineer to be shiny (although it does help :) ). Plenty of stuff you can buy (just not my shirt, sorry ;) ):


just go to the aptly named 'shiny things' store
just go to the aptly named 'shiny things' store


and if you're into drum and bass, they have you covered too ;)
and if you're into drum and bass, they have you covered too ;)

Anyway, let's look at EDC as a whole this year. Maybe I got lucky with my shuttle stop didn't have a wait that wasn't as terrible as last year. The ride was still closer to 90mn, later in the evening, which sucked somewhat (still about 2h30 from hotel to festival)


hilarious. Yes, we were ready... for the great event :)
hilarious. Yes, we were ready... for the great event :)

The VIP area had a swimming pool (no good with my electronics), a ball pool, and video games:



oh yeah, even a maze
oh yeah, even a maze




Some decors were straight out of burning man:


first saw this at burning man years ago, super fun, especially if you're on something
first saw this at burning man years ago, super fun, especially if you're on something









you could use diffraction glasses if you were sober
you could use diffraction glasses if you were sober

Let's not forget art cars, all of which I've seen at burning man:



They had even more fair attractions this year:






Let's not forget about bad ass fireworks every day:








Fireworks Day1:

Fireworks Day2:
Fireworks Day3:

Now, the music sets I saw on Day #1:



Drum and Bass was fun to listen to for a while,

they had awesome visuals
they had awesome visuals



I'm a big pendulum fan
I'm a big pendulum fan

stargate visuals, well done
stargate visuals, well done







Of course, Trance, trance, and more trance :)

fancy control console
fancy control console




ok, using the 'help' output of the DOS box on windows, was a bit lazy :)
ok, using the 'help' output of the DOS box on windows, was a bit lazy :)





Day #1 Summary:

Now, we can move to Day #2:



Circuit Grounds had Hardwell and Armin Van Buuren that night:





Day #2 Summary: https://youtu.be/3aHCxI5Xq34

Finally Day #3:

Drum and Bass DJs definitely like to stand on their DJ table :)
Drum and Bass DJs definitely like to stand on their DJ table :)





Cosmic Gate
Cosmic Gate

ATB
ATB






Let's finish with a sunrise:










Day #3 Summary:

I won't go into how hard it is to timeshift 12H overnight (I got up at 06:00 the previous day to go to a racetrack and went to bed at 07:00 the next night. That was tough.
Insomniac did a great job with the lineups, definitely more trance now compared to the first year I went. I was not a huge fan of the way quantum valley looked, it sure was hard to get good pictures through all those metal stands. I'm also under the impression that at least on the first day, they cranked the bass way up, maybe in a misguided attempt to compete with drum and bass across, to the point that you couldn't really hear much of the music anymore. Thankfully it was a lot better by day #3.

The shuttles worked a bit better this year, although the premium shuttles were kind of a joke. You were supposed to tell them months early what time you were going to go and come home, and have that be the same every day, not that you had lineups with times anyway. I ended up taking the standard shuttle most days, which sadly got moved farther away from my hotel I had already booked. I don't understand why they simply don't have VIP lines for the standard shuttles and be done with it. Having 2 different shuttle systems with different locations and less flexibility on the premium ones, makes no sense at all.

Thanks to Insomniac for the event and lineups. Also, thumbs up to anyone who came with costumes and tasteful totem poles (sadly, there are some really crappy ones too, which sometimes end up being right in the front stage, ruining all the pictures I was trying to take).

See more images for Another EDC in Las Vegas
2018/05/12 back to Speedzone Dallas, 11.5 years later: disappointing :(
π 2018-05-12 00:00 in Cars
It's been eons since we went to Speedzone in Dallas in 2006, so I was looking forward to going back.


They added a slick track where the karts have little traction and you can practise drifting. That's actually a lot of fun, and not something I've done anywhere else.


Their main kart track sadly got toned down a lot, to the point that it was boring and pointless. I was a full gas the entire time, never had to brake.

the 2 person kart was more powerful and more fun thankfully
the 2 person kart was more powerful and more fun thankfully


They added electric karts that were also underpowered and had no lap times.




The dragsters were still there, but sadly I kept coming 2nd to dragster #1 because even though I got off the line at full speed every time, the other one was just faster and would first catch up and then pass me, disappointing.






fastest response time
fastest response time

But oh well, it was still a fun enoug day out :)

2018/04/28 Trance Family SF 8 at Midway, SF
π 2018-04-28 00:00 in Clubbing
It's already been a year since the great TFSF 7 party last year, I was definitely looking forward to this new one in an even bigger venue.

I got to try my new shirt, I had spent weeks working on:



found a friend :)
found a friend :)

The outdoor patio was nice, and the psytrance wasn't bad either :)



Khromata did a nice set, quite enjoyable
Khromata did a nice set, quite enjoyable


Other inside pictures:





The main room sadly was way too loud most of the time, even with earplugs, kind of a bummer. At times, it was also way too smoky. At times, it was not possible to take any decent pictures when it was barely possible to see the stage due to smoke. On the flipside, that allowed me to spend more time in the Trance Classics room, which worked out totally fine :)






did I say too smoky?
did I say too smoky?


Other rooms:




I spent most of my time in the Trance Classics room. It was smaller, but it was definitely the best music for me :)


David did great work with the video visuals
David did great work with the video visuals





then, my friend DJ Blurr took over
then, my friend DJ Blurr took over





Taj was last, spinning vinyl
Taj was last, spinning vinyl

I definitely had a great night. The venue was nice, the decors were also good, and the choices of DJs and music were great. Thank you!

Quick sample/summary video:

And DJ Blurr's entire set:

Oh, and if you're curious, an early demo of my new shirt prototype, which I got to try for the first time that night (still work in progress):

See more images for Trance Family SF 8 at Midway, SF
2018/04/23 FastLED::NeoMatrix library
π 2018-04-23 00:00 in Arduino
I've been a fan of Neopixels and Adafruit's Neomatrix library since last year. Why is Neomatrix special? It allows you to create Neopixel displays and treat them like a panel display on which you can apply Adafruit::GFX primitives.

The problem is that https://github.com/adafruit/Adafruit_NeoMatrix only supports the https://github.com/adafruit/Adafruit_Neopixel backend which in turn only supports neopixels, and only in a serialized fashion. Serialized means that if you have 1024 pixels (32x32 matrix), it takes about 35 to 40ms to send a single frame, which means you can only update at a 25fps rate, which is not that good.

https://github.com/FastLED/FastLED fixes this by offering support for a lot of different kinds of LEDs, but also for offering parallel output on multiple MCUs, allowing you to get up to 16x faster updates by segumenting the strip to update sequentially. It also offers much nicer primitives like automatic fading, and the ability to have multiple independent strips of different lengths that can display different patterns.

Neomatrix is aweseome since it offers access to the GFX library primitives (circles, lines, rectangles, and fonts), but since it didn't work with a FastLED backend, I ported it to FastLED.

You can get the code here: https://github.com/marcmerlin/FastLED_NeoMatrix
You can also see my NeoMatrix Shirt on this page


Hello world
Hello world

Thanks to Adafruit::GFX, it's easy to display fonts and bitmaps
Thanks to Adafruit::GFX, it's easy to display fonts and bitmaps

32x32 is slightly better to display bitmaps
32x32 is slightly better to display bitmaps


This will be the display on my shirt
This will be the display on my shirt

GFX allows drawing lines, circles and all
GFX allows drawing lines, circles and all

Fonts can be of any size
Fonts can be of any size

See more images for FastLED::NeoMatrix library
2018/04/17 Private BBR Track Day at Thunderhill
π 2018-04-17 00:00 in Cars
Rob setup a few track days for his customers at Thunderhill.

Luckily the other folks hired a pilatus PC12, which I was able to join instead of flying my own butt as usual. It didn't suck :)





Once at the track, few people, lots of track :)







Sadly my car apparently has a wire harnest loose somewhere, causing some errors when I was driving. We tried multiple places, but haven't quite found which one is causing issues yet.


Nonetheless, we got it driveable and I was able to get a 1:48 lap before running out of talent and tire grip (not sure which one came first :) ). The car can go faster, but that's the best I could do that day. I guess I still have a bit of room to improve :)

Thanks to Rob for setting this up.

2018/04/15 Jean Michel Jarre @ San Jose City National Civic Theatre
π 2018-04-15 00:00 in Clubbing
Like I was saying in my previous post, I've been a fan of Jean Michel Jarre since the 1980's when I was a teenager. Along with Vangelis, Jean Michel Jarre is one of the founders of Electronic Music. The two of them were popular before anyone else was even around doing any EDM.

Well, after never having managed to see JMJ live in all these years I was listening to his music in France, I now get to see him twice in less than a year. His last show was less than a year ago at the Berkeley Greek Theatre. It feels so weird to see him twice in such a short time when I had never seen him in the last 30 years before that.

A few pictures:














great show, fun to see it again
great show, fun to see it again

2018/04/12 Late Season Quick Powder Day at Sugarbowl
π 2018-04-12 00:00 in Snow
This year was not the best snow year in Tahoe, it only got good in March, making for a short season. After that, we got warm weather and a lot of melting.
And out of nowhere, a cold front came. Unfortunately, the initially promised 12 inches for sugarbowl became a mere 5 inches by the time we arrived, so that was a bit of a let down, but eh, it was still snow :)
This wasn't quite enough to cover the ice underneath and wind blown locations were sheer ice given that the new snow was actually cold and light.

I hadn't been to Sugarbowl in over 10 years, so it was nice to go back and give it a shot. A big thanks to Marius who was a trooper and drove us there and back when I was clearly not awake.









By the end of day, clouds came in and it was starting to ice up a bit, so we had enough and went back.

2018/04/04 First Droid and Friends of the Year at Thunderhill
π 2018-04-04 00:00 in Cars
It was early in the season, but we got lucky enough with the weather. I however was rusty for sure, and apparently managed to mismanage the tires on my first session, and after that I never really got good times due to limited traction from the tires by the time I was making fewer mistakes and getting faster.






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