[youtube=http://www.youtube.com/v/exTpD0–BCo]
[Tixlegeek] used a Motorola 68HC705J1 development board to remotely control his home through his cellphone. The video above, as well as [Tixlegeek]’s website, is in French, though the video has been captioned. The development board (called the ERMES125) is controlled by a PIC externally. It has an array of LEDs, and apperantly a few high voltage relays. The PIC is connected to a laptop through a serial interface. The laptop is running a small web server, which uses CGI to control the PIC from a webpage. This system allows [Tixlegeek] to log onto the webpage from his web enabled phone, click a few buttons, and have appliances turn on or off through relays controlled by the PIC (via serial signals from the laptop).
Year: 2009
Diamond Thermal Paste: Update
The need to conduct laboratory-style experiments runs deep in some people. [Freddyman] built an apparatus to test out several commercial and homemade thermal pastes, including the DIY diamond thermal grease we reported on last month. He setup each experiment in the middle of an air conditioned room, ran the heat sink fan for 30 minutes to equalize the temperature, then turned on the DIY heat generator that the paste and heat sink were connected to. He’s got a lot of data from tests he ran with the eight thermal conductors; air (using no paste), Arctic Silver 5, Ceramique, Dow thermal fluid, pure silicone oil, silicone and diamond slurry, Dow fluid with diamonds, and the Inventgeek.com remake.
One of the big problems with DIY paste is the air bubbles that are introduced into the slurry as you mix in the diamonds. All of the homemade pastes except one were put in a vacuum chamber in an attempt to remove tiny bubbles. The one that wasn’t put in the vacuum performed the worst of all the thermal conductors. In all cases, the commercially available products performed quite well while the DIY solutions delivered mixed results.
DIY Coffee Table Scale
[Guus] screwed together this coffee table which doubles as a scale. No welding was required to put it together – just some bolts, pulleys, miscellaneous fittings, and an original design. The weight is indicated through the (unlabeled) position of the counterweight arm. Currently it is limited to measuring 10kg (22 pounds), but can easily be boosted by adding a heavier counterweight. It looks pretty robust, maintenance-free, and fitting for any living room workshop’s weighing needs. [Guus] is also the proud inventor of the rock radio, and he is working on creating Man-Y-Man: a modular play system allowing children to create up to 1520 unique creatures.
Toyaanisqatsi: Time Lapse Control Using LEGO Parts
[youtube=http://www.youtube.com/watch?v=Fm1fFQfGc9M&feature=player_embedded]
A simple panning motion can add impact to the already-dramatic effect of time lapse photography. To accomplish this, frugal cinematographers sometimes build [Rube Goldberg] contraptions from clock motors, VCR parts or telescope tracking mounts. Hack a Day reader [Stephan Martin] has assembled a clever bargain-basement system using an Arduino-driven stepper motor and a reduction gear system built up from LEGO Technic parts, along with some Processing code on a host PC to direct the show.
While the photography is a bit crude (using just a webcam), [Stephan’s] underlying motion control setup might interest budding filmmakers with [Ron Fricke] aspirations but Top Ramen budgets. What’s more, unlike rigid clock motor approaches, software control of the camera mount has the potential for some interesting non-linear, fluid movements.
Take Command Of Your BASH Prompt
[Joshua] has put together a list of BASH prompt customizations. The command prompt is used in a command-line interface to show that the system is ready for the next command. Often times this is nothing more than a user name, host name, and working directory:
mike@krusty:~$
[Joshua’s] customization examples can be used to color code the information in your prompt, change what information is displayed, and make the prompt respond differently when an invalid command is typed. A BASH prompt reference is helpful in deciphering what each of these commands do. The easiest simplification is to understand that non-printing characters (such as color codes) are surrounded in escaped square brackets. For example, line 1 is the sequence for Red, line 2 is the sequence for Dark Grey, and line 3 sets a simple prompt to display in Red and all text after that to be in Dark Grey:
\[\e[0;31m\] \[\e[1;33m\] PS1="\[\e[0;31m\]\u@\h:\w\$ \[\e[1;30m\]"
Harry Potter Marauders Map Realized
After reading about cheap wireless for microcontrollers, [Leigh] left a comment about his Marauders map. Much like the Harry Potter version, whoever holds the ‘map’ is able to see the location of the ‘marauders’ within certain bounds. Unlike the magical version however, each person being tracked needs to hold a PICAXE 08M, GPS, and 433.92MHz transmitter: while the map needs a computer running his Python script and a receiver of the same frequency. It has the potential for locating people, but we feel it might be better off in a swarm robotics setup.
Programmable Spring Actuator Legs
[youtube=http://www.youtube.com/watch?v=_g79mOSvSsE]
This proof of concept shows an interesting way of making robotic legs. They are using programmable spring actuators to make these legs function as though they had a “reflex”. The builder pulls the robot along on a leash. As the leg reaches its limit of backward motion, a signal is sent from the shoulder down to the knee that lifts it, causing it to return to the forward position. A signal is also sent to the opposing shoulder to suppress the lift reflex, keeping them from both stepping at the same time. The resulting motion is very organic feeling. We’re curious how this could be implemented in a robot which moves under its own power.
[via makezine]
