as mentioned on my recent tweets, was looking for a low cost multi-display solution about couple weeks. gaming oriented gfx cards already providing this feature but they costs as a new computer and requires gigantic power supplies. that will an unnecessary investment.
finally i purchased an usb displaylink adapter with a fast decision. i supposed its an gfx chip which can communicates with mainboard via usb port.
..But it's not
It creates a virtual desktop on your system by using software and captures realtime video from it. then device receives this video with 50~250ms delay. i don't sure that's applicable in commercial industry but it's terrible idea.
Maybe their certified products working without any trouble but i did my second mistake by purchasing an unknown chinese brand with high price. its getting warm on first usage and resets itself due to overheating. and i decided to use it by replacing heatsinks instead of refund. this time heatsink melts its plastic cover, and i installed a small fan into it. wtf. this is madness.
ofcourse i didn't use it due to its noise, i researched more and finally found the Sapphire HD6450 Flex edition it uses an unique technology called "Flex" to get three displays same time. that's exactly what i need but its obsolete a little bit and hard to find in local market. then found on someone's ebay store later.
after the two weeks, i received item, installed it to my mini-itx case and sent that usb-crap to trash. if you're planning a similar screen setup, stay away from displaylink devices.
after the few commercial projects, i got some "me-time" at last. i sold all of my geek toys and some trash on ebay except few arduino boards and shields. and i tried to make something useful from this spare parts.
WS2811 is a digital adressable rgb led controller unit. some eastern tech-manufacturers developed independent color led strips by combining rgb leds and that chip. i purchased half-meter length sample and tried few tests with arduino. looks like working ok but the problem is ATmega8 clock rate too slow for this kind operations. an ARM or FPGA based board required for real light shows.
The 80's childs are familiar with virtual reality term. we seen this subject in the action at johnny mnemonic, the lawnmowerman etc.
if you're not living in a cave, probably should know the oculus rift. it was a kickstarter campaign about a simple vr helmet (hmd) project and also succeeded. its currently in development stage. price is 300$ but you need at least ~650$ including shipment, customs etc. if you're staying in europe.
Today, i experienced it about five minutes in somewhere and decided to write first impressions which memories are still fresh.
- It can provide exact virtual room feeling with built-in gyros. your brain will adopt new visual input source in few seconds.
- Completely plug & play. no detailed configuration needed.
- Image quality not good for still pictures but enough for a fps simulation.
- Good price.
- You can clearly see pixels, that's annoying.
- User only see @ of 21cm (4 inch) screen from 3-4cm distance. rest of screen area wasted.
- built from cheap plastic, not designed for long life usage.
- lenses are easily vaporizing by your own breath and blocking vision after few minutes later.
- I know its development version but still too big for human head..
- All games must render two copies of scene in splitscreen. that means high usage of system resources.
- Causes headache and dizziness in 3d sbs games after 10 minutes of gameplay.
- Material is not hygienic, probably it will cause bacterial infections in long-term use.
actually its a stereoscopic viewer with aspheric lenses. all trick turning around splitscreen special games and third party extensions such as tridef. if interested with its technical part, this guy was created a exact clone of oculus and shared details on his blog
as the whole crafty geeks knows, nike has a rvsp system via twitter. they are offering free footwears to followers who sends promotion codes.
im absolutely strange their marketing strategies and not so interested. but my interest point is that cheap pictures. actually you can find this cloaked text block via any graphic editor. just open image, decrease color depth and floodfill an empty area. thats it! you found the block. any ocr engine can easily read that result.
i created a php function which can process same steps via programmaticaly. you can find it in devzone section.
other requirements for a full featured rvsp bot:
- grab twitter client class
- install tesseract OCR engine
and you have to write few lines of code which can process this steps:
1 - read nike account's timeline with a spesific time interval (~30sec)
2 - if new tweet appears with url "pic.twitter.com/***" download that image
3 - extract highlighted hashtag with this function
4 - convert extracted part of image to string with tesseract ocr library
5 - send DM to nike's twitter account with this class
aka Mass Disk Copier. can be used for copy a directory to multiple flash drives. also can handle multiple copy operations in same time. useful for manufacturing software support kits.
I get this trick from a sysadmin friend. it allows to enter system level shell access in Windows Vista and later versions. useful for bypass UAC and ntfs file permission issues.
sc create SuperCMD binPath= "C:\WINDOWS\system32\cmd.exe /c c:\windows\system32\cmd.exe" type= own type= interact
net start supercmd
and you're in system desktop now.
First RC connection tests on autonomous quadcopter project named -Wintermute-. Testing around %10~20 thrust rate with 12a speed controller.
While i get battery packs, installed components on body and it still powerless. There is science in a third world country.
First, tried with cd-rom motors but no luck. and purchased four piece turnigy brand 1100kv brushless motor. maximum thrust of all of them, enought to carry 2kg payload. Rest of body built from scrap analog tv antennas and balanced with small gibs. current weight is around ~900gr. technically it can handle 1.5kg i guess.
I decided to use a custom stabilization software named hefnycopter because completely opensource and accepts pure pwm input. original kk board only can accept ppm signal. also software has extra features like dynamic mode change (+ and x configuration) fast installation etc. im planning directly drive it via arduino and wifi & gsm shield. if it fails, i will try Multiwii lite board. looks like it also supports auto leveling features.
Lithium-Polymer batteries really sensitive than other types. if exceeds minimum or maximum voltage, can easily take damage or explode. i experienced it
fpv videos will be available soon.