What I've been up to in Hong Kong - Page 1
Forum section: electronics / projects

author: mikeselectricstuff
author_rank: Super Contributor
timestamp: November 20, 2015, 02:05:58 am
content: Each snowflake is made up of 60 LED strips, each containing 6 RGBW LEDs and a PIC12F1501. All fixed together with plastic rivets and interconnected with SIM card connectors.Total 270 snowflakes, 16,200 PICs, 97200 LEDs

author: xrunner
author_rank: Super Contributor
timestamp: November 20, 2015, 02:11:44 am
content: What an electronic work of art - very impressive.

author: alex89
author_rank: Contributor
timestamp: November 20, 2015, 02:34:36 am
content: Very clever designHave you had any issue at all with connectors reliability ?

author: mikeselectricstuff
author_rank: Super Contributor
timestamp: November 20, 2015, 02:50:28 am
content: Quote from: alex89 on November 20, 2015, 02:34:36 amnot yet.....

author: Miles Teg
author_rank: Regular Contributor
timestamp: November 20, 2015, 03:02:18 am
content: Ho yes, very intersting connection system.How did you get the idea?

author: ataradov
author_rank: Super Contributor
timestamp: November 20, 2015, 03:03:41 am
content: Did they do it just for Christmas/New Year? Or it is actually going to be there for some time?

author: coppice
author_rank: Super Contributor
timestamp: November 20, 2015, 03:11:38 am
content: Quote from: alex89 on November 20, 2015, 02:34:36 amThe real answer will come on 12th night, when the whole thing is turned off.Interestingly, this display is just for Christmas. It is common in HK for Christmas decorations to be designed so they can be reconfigured in early January as an appropriate Chinese New Year's display (i.e. remove anything white, which symbolises death and funerals in Chinese culture, and play up the red, which symbolises good fortune).Mike employed some rather smart reuse of standard parts in this design. The contacts are a bare SIM card connector (i.e. just the gold pads, with no metal card retainer part) on one board, pressing against ENIG pads on another board. Plastic pop rivets hold the two boards together, and the whole thing seems to work well. Mike used quite a lot of rivets, so the structure is pretty stable. I watched several snowflakes being assembled. This consisted ofThree people furiously pressing pop rivets into holes for several minutesA programmer sending patterns around the segments of the flake to check each oneThe three people prodding the rivets on any flake segment that misbehaved - every failure I saw was due to something not being properly pushed into placeA clean run of the pattern testStorage in a custom made crate, for delivery to Pacific PlaceRepeat hundreds of times over a couple of weeksAfter any initial assembly issues were addressed the flakes seemed rock solid.Pacific Place is one of the most up market malls in Hong Kong, so this is a prestigious place to be.

author: mikeselectricstuff
author_rank: Super Contributor
timestamp: November 20, 2015, 03:14:42 am
content: Quote from: ataradov on November 20, 2015, 03:03:41 amCurrently only til Jan 4, but they are talking about using the parts from all 5 sections to make a big permanent display where th etree currently is some time next year

author: mikeselectricstuff
author_rank: Super Contributor
timestamp: November 20, 2015, 03:18:38 am
content: Quote from: coppice on November 20, 2015, 03:11:38 amThe primary purpose of that was to program the individual addresses into each stripThe jig uses a similar modular construction to the flake so it can easily be reconfigured to make different shapesIf we do re-use the PCBs in another form I think we'll need to make a fixture to pop all the rivets out, as it's much more work getting them out than in.

author: iampoor
author_rank: Frequent Contributor
timestamp: November 20, 2015, 03:46:03 am
content: How are all of these powered?Very impressive.

author: coppice
author_rank: Super Contributor
timestamp: November 20, 2015, 03:48:34 am
content: Quote from: iampoor on November 20, 2015, 03:46:03 amWith electricity. Surely the interesting question is how much power do 100k LEDs require.

author: mikeselectricstuff
author_rank: Super Contributor
timestamp: November 20, 2015, 04:17:33 am
content: For first 4 frames we are maxing out all available sockets if we did 100%rgb+w , about 8kw from memory. Tree about 5.5kw

author: calzap
author_rank: Frequent Contributor
timestamp: November 20, 2015, 05:39:07 am
content: Mike,Very impressive and creative. Was everything preprogrammed or can it be reprogrammed in the sky? Are the suspensory cables (at least some of them) also power conductors or is suspension independent of electrical supply?Mike in California

author: TerraHertz
author_rank: Super Contributor
timestamp: November 20, 2015, 02:52:36 pm
content: That's neat.It looks like all the hexagonal units are independently suspended, and not directly interconnected?Is the design also able to work with extended regular matrices?Is there any processing power on the modules or are they all just commanded from something central?If something like this could be connected together in an extended matrix, with a bit of processing in each node, you could do cool chaotic system stuff, like Game of Life. I guess there'd have to be multiple power feed points though.I really like that interconnect idea.Hmm... if the hubs were a bit flexible (and came in 6 & 5 arms) then geodesic structures would be possible. Though, then there'd have to be several different length segment pieces.

author: brabus
author_rank: Frequent Contributor
timestamp: November 20, 2015, 02:58:17 pm
content: Very neat, very clever and very nicely made, as usual!With a total power in the range of 8 kW, I would be very curious to see the power distribution strategy.I had color drift issues when driving a chain of 120 WS2812: the first LED had 5.00V, the last one barely 4.60V --> the first one was full bright white, and the color drifted progressively towards light red to the end of the chain!I had to struggle to bring additional low resistance 5V paths to various points of the string.

author: DanielS
author_rank: Frequent Contributor
timestamp: November 20, 2015, 04:21:25 pm
content: Quote from: brabus on November 20, 2015, 02:58:17 pmI'm guessing that each hub (36 LEDs) has its own power feed. That's still ~1600A total at 5V, which means either quite a few AC-DC converters or massive 5V bus bars hidden behind those top form supports.

author: Artlav
author_rank: Frequent Contributor
timestamp: November 20, 2015, 05:13:18 pm
content: Quote from: coppice on November 20, 2015, 03:11:38 amPlease tell me he is not getting paid with exposure...?

author: Macbeth
author_rank: Super Contributor
timestamp: November 20, 2015, 06:16:20 pm
content: Great stuff Mike,I especially like the fact that dad can easily tear it apart and pack it into the box of baubles and tinsel and leave it up in the attic until it comes out again next yearI hope you got paid for this as an "art piece" rather than an "electronics project" as one of them seems to command a lot more cash than the other!

author: alanambrose
author_rank: Frequent Contributor
timestamp: November 20, 2015, 06:55:23 pm
content: Hmmm, the MES law of LED count vs time suggests a million LED project in the not too distant future?

author: mikeselectricstuff
author_rank: Super Contributor
timestamp: November 20, 2015, 08:17:51 pm
content: Quote from: DanielS on November 20, 2015, 04:21:25 pmEach strip has 3 rgbw LEDs per side, in series to run from 24v

author: coppice
author_rank: Super Contributor
timestamp: November 21, 2015, 08:46:18 am
content: Quote from: Artlav on November 20, 2015, 05:13:18 pmIf you are creating artworks, your main exposure to prospective clients is your existing artworks, and being in prestige venues helps a great deal.

author: mikeselectricstuff
author_rank: Super Contributor
timestamp: November 21, 2015, 10:54:41 am
content: Quote from: TerraHertz on November 20, 2015, 02:52:36 pmEach is seperately hung, but pairs are linked together to lock the rotationQuoteNo processing - it's just a pixel display driven by an external system. Each drop cable carries 24V power and TTL data at 125kbaud. Up to 12 flakes plug into splitter boxes on the frame, which distribute (and fuse) power, and split data out from four 2Mbaud RS485 buses.QuoteOr you use rigid corners and longer, more flexible PCB strips.Stay tuned

author: mikeselectricstuff
author_rank: Super Contributor
timestamp: November 21, 2015, 10:58:56 am
content: Quote from: alanambrose on November 20, 2015, 06:55:23 pmIt's a bit random - I think the biggest to date is Heathrow airport at about 350,000 LEDshttp://cinimodstudio.com/project/emergence/

author: amyk
author_rank: Super Contributor
timestamp: November 21, 2015, 05:43:37 pm
content: Quote from: brabus on November 20, 2015, 02:58:17 pmIf it's an art installation, that could be a bonus feature - gradients for free!

author: mikeselectricstuff
author_rank: Super Contributor
timestamp: November 21, 2015, 06:36:20 pm
content: Quote from: amyk on November 21, 2015, 05:43:37 pmOne advantage of art projcts as opposed to commercial products is that things that might be regarded as faults can be re-interpreted as artistic quirks

author: coppice
author_rank: Super Contributor
timestamp: November 21, 2015, 07:00:47 pm
content: Quote from: mikeselectricstuff on November 21, 2015, 06:36:20 pmSimilarly the only real bug you can have in a game is one that completely locks it up. Everything else is just "character"/

author: TerraHertz
author_rank: Super Contributor
timestamp: November 24, 2015, 07:23:21 am
content: Quote from: mikeselectricstuff on November 21, 2015, 10:54:41 amHmm... but then the overall shape would be a bit wobbly, and hard to keep looking 'round' despite distortions due to suspension points.Also the strips wouldn't bend spherically, but rather in centenary curves, which could look a bit odd since the overall shape would be a series of discontinuous curves. Unless you did some very careful profiling of the width of the PCB pieces along their lengths, with the middle thicker than the ends so the amount of bend was constant.Btw, are you aware of the detailed geodesic chord length and joint angles tables (for all the major dome geometries) in the old 'Domebook I & II' ? I have them; if you need them and can't find a copy I could scan parts.Also google 'tensegrity structures'. These are cool looking. Just begging to be made out of electronics and wire. The wire needs to be non-stretchy; stainless multi-stranded fishing line and crimp ferrules work well.)One way to do rigid hubs, with straight struts, interconnects and fasteners the same as you did there, would be injection molded hubs with little flexible PCB clip-ins.

author: coppice
author_rank: Super Contributor
timestamp: November 24, 2015, 07:40:37 am
content: Quote from: TerraHertz on November 24, 2015, 07:23:21 amI suspect thick stiff hub boards, combined with thin strip boards, that will form into a nice curve, could be used to construct a soccer ball like assembly.

author: bookaboo
author_rank: Frequent Contributor
timestamp: November 24, 2015, 02:11:59 pm
content: Is the PCB aluminium or FR4 with white silkscreen and lots of vias?

author: mikeselectricstuff
author_rank: Super Contributor
timestamp: November 24, 2015, 03:34:50 pm
content: Quote from: bookaboo on November 24, 2015, 02:11:59 pmFR4 - there are no major heat issues - LED current is only about 15mA per RGBW

author: mikeselectricstuff
author_rank: Super Contributor
timestamp: March 21, 2016, 01:46:00 pm
content: Just found a making-of video - ignore all the "little prince" stuff - that was down to someone else!

author: Mr Smiley
author_rank: Frequent Contributor
timestamp: March 21, 2016, 03:21:09 pm
content: Sorry, off topic but relevant to thisFor some strange unknown never solved reason, I've never ever been able to play vimeo videos. Linux and FirefoxI get the first frame and that’s it, frozen ( the video that is, not anything else ).

author: WillHuang
author_rank: Contributor
timestamp: March 21, 2016, 04:23:06 pm
content: Adobe flash not installed?Sent from my SM-N900W8 using Tapatalk

author: Molenaar
author_rank: Regular Contributor
timestamp: March 21, 2016, 04:27:22 pm
content: Quote from: Mr Smiley on March 21, 2016, 03:21:09 pmI also often get this, and it seems dependent on the sample rate my sound card is currently set to. For youtube, I often have to change it from 44.1K to 48K, after which everything does smoothly.

author: Macbeth
author_rank: Super Contributor
timestamp: March 22, 2016, 06:28:24 pm
content: For those playing "Where's Mike?" I think I spotted him at 00:07 in a black '1. On time' T-Shirt and at 00:32 in a white Timberland T-Shirt

author: Towger
author_rank: Super Contributor
timestamp: April 20, 2016, 08:21:11 pm
content: The was last spotted on the Amp Hour, comming clean on his phone hacker past.