#Craig-Wright claims, in 2013, that he can make a (modern, but poor quality) pencil from scratch. But he hasn’t done it yet. #bootstrapping
#Craig-Wright explains #mining of graphite in order to make his pencil from scratch. #materials
Thomas Thwaites has published a book about his Toaster Project, where he made a toaster from scratch, inspired by the Hitchhiker’s Guide to the Galaxy. #bootstrapping
The tile-roof-hut guy built a fireplace with a chimney and a larger kiln for firing larger pots for cooking. #bootstrapping
Jeri Ellsworth makes transistors and integrated circuits at home. #DIY #bootstrapping
overview of the Global Village Construction Set #bootstrapping project.
on the value of tolerance in #politics and #social-justice
#Public-shaming campaign of a female gamer who streamed on Twitch culminates in someone #SWATting her.
US gross international trade (imports + exports) is US$5T per year, 28% of its GDP and almost US$16000 per capita. #economics
ex-Barclays CEO thinks banks are “Approaching the Uber moment” (due to #bitcoin?) over the next decade.
#pdf #paper showing that syntax highlighting is mildly helpful in programming, especially for novices. #UX
#NodeMCU is an open-source firmware for programming #ESP8266 WiFi 32-bit #microcontroller #hardware in #Lua. Doesn’t run Node.js (of course!) but has a node.js-style network API. 64 kilobytes of instruction RAM, 96 kilobytes of data RAM, 64 kilobytes of boot ROM, and 4 megabytes (!!!!) of Flash. A breakout board costs US$10 from Adafruit, or US$7 in a 24mm×16mm×3mm (1.15 mℓ!) surface-mount PCB.
#ESP8266 #hardware #pdf #datasheet (sort of anyway). 12μA in sleep mode. #ARM Thumb apparently, specifically a Tensilica Xtensa LX3. 80MHz.
#poem on sorrow and brokenheartedness
new US$5 #Raspberry-Pi without the Ethernet.
Espruino is a STMicroelectronics #ARM Cortex-M3 #microcontroller board that runs #JS for US$25, or US$40 from Adafruit. Reputedly you can run the Espruino firmware on #NodeMCU boards.
Tessel is a 180MHz #ARM Cortex-M3 LPC1830 board with 32MB of SDRAM and 32MB of Flash that you can program in #JS.
comprehensive overview of the #microcontroller #hardware landscape as of today, starting from the Raspberry Pi. Mentions that the ARM11 in the #Raspberry-Pi is an ARMv6 rather than ARMv7 and therefore won’t run most current Linux distributions.
John Nagle mentions Edison’s “chalk telephone”, which used the #Johnsen-Rahbek effect to directly control friction between a rotating damp chalk cylinder and a wiper. “Silicon carbide was much better than wet chalk, and this effect was used in IBM line printer clutches.” Perhaps this could be used for controlling a 3-D printer. #materials
Development of the Electrostatic Clutch: “A brief historical review of the electrostatic clutch operating on the #Johnsen-Rahbek effect is presented. #Mechanical design of a clutch, special lubrication, and the fabrication of electronically conductive clutch facing material are described. A high-speed, high torque-to-inertia ratio test model with bi-directional shaft control is described. With the clutch operating at 2500 rpm on 30 milliamperes at 150 volts, torques over 80 inch-pounds are available. The most useful single property of the electrostatic clutch is its fast response time. It can actuate levers, interposers, print hammers, optical gates, etc., in fractions of a millisecond; it can accelerate shafts to high rpm’s with moderate loads in a few milliseconds from extremely low input control energy.” Fitch 1957. Note that 30mA×150V is 4.5W, while 80 inch-pounds × 2500 rpm is 2400 W, an amplification factor of >500.
patent on a new version of IBM’s electrostatic clutch using the #Johnsen-Rahbek effect in 1979. #patents