Power Cycling A Problematic Modem

June 29, 2010 by Mike Szczys 53 Comments

[Gigawatts] struggled against a shoddy Internet connection for quite some time. Changing modems, having the line serviced, and spending far too much time on the phone didn’t do any good. In fact, the only thing that fixed the problem was power cycling the modem once it stopped responding. His solution was to automate the power cycling process. He added a cron task to his router which is running DD-WRT, a favorite firmware alternative for hacked routers. The script monitored the WAN connection and when it went down it would toggle one of the serial port pins. He whipped up an outlet box with a relay in it and used that serial pin to cut the power going to the modem. A workaround yes, but it was the only thing that brought an end to his frustration.

Intelligent Ground Vehicle Competition 2010 Day Two Report

June 7, 2010 by Gerrit Coetzee 11 Comments

Culture Shock II, a robot by the Lawrence Tech team, first caught our eye due to its unique drive train. Upon further investigation we found a very well built robot with a ton of unique features.

The first thing we noticed about CultureShockII are the giant 36″ wheels. The wheel assemblies are actually unicycles modified to be driven by the geared motors on the bottom. The reason such large wheels were chosen was to keep the center of gravity well below the axle, providing a very self stabilizing robot. The robot also has two casters with a suspension system to act as dampers and stabilizers in the case of shocks and inclines. Pictured Below. Continue reading “Intelligent Ground Vehicle Competition 2010 Day Two Report” →

Intelligent Ground Vehicle Competition 2010 Day One Report

June 5, 2010 by Gerrit Coetzee 19 Comments

The Intelligent Ground Vehicle Competition (IGVC) is the precursor to the DARPA Grand Challenge, and in many ways it is just as difficult. We have the pleasure of being at the competition this year with the Tennessee Technological University Autonomous Robotics Team. The teams at the competition pull off some amazing home-brew robotics, so we’ve decided to do a short section on some exemplary robotic hacking each day of the competition.

Today’s robot comes from the York College of Pennsylvania. The robot, dubbed “Green Lightning”, features an impressive set of custom made hardware.

We interviewed the team, and got a pretty thorough rundown of their robot with pictures after the jump. Continue reading “Intelligent Ground Vehicle Competition 2010 Day One Report” →

JTAG Programming Over A Network

June 1, 2010 by Mike Szczys 18 Comments

[Matt Evans] was running up against the common programming gotcha caused by disappearing parallel ports. For years he had used a JTAG parallel cable when working with FPGAs but recently realized he no longer owned any machines with that interface available. Instead of shelling out $50 for a USB programmer he a programming interface from an old router.What he’s doing is bit-banging using Linux. In this case it’s a router running a version of Linux which makes his setup Internet friendly but this could be done in the same basic manner on any Linux device with enough available I/O to connect to the device you are programming.

CPU As A Heat Sink

May 1, 2010 by Mike Szczys 51 Comments

We’ve noticed that wireless routers pump out a bunch of heat. [Jernej Kranjec] wanted to make sure that he didn’t fry it once he started adding more load to his router using OpenWRT. What he came up with is the idea of using an old CPU as a passive heat sink. He applied a bit of thermal paste to the center and some super glue to the corners. You can see the finished product is an old AMD chip adhered “dead bug” style to the stock processor. We’d bet it’s not very efficient compared to an aluminum or copper heat sink, but it normally would have no help in shedding those extra degrees.

CNC Project Roundup

December 29, 2009 by Jakob Griffith 10 Comments

We asked for CNC projects, and wow did you guys deliver!

First up is [J-J Shortcut’s] MDF based CNC. He’s made three thus far, with the most recent costing about 180 euro and taking 2 months to build.

[Qwindelzorf] has also constructed a multitude of CNC machines including this industrial size router and this smaller miller.

Finally, [Mick’s] large steel CNC which just made its first cut only a week ago!

Keep up the great work guys, CNC machines are not easy to build and your accomplishments are ones for the record books.

CNC Circuit Board Fabrication

November 23, 2009 by Mike Szczys 35 Comments

[Jonathan Ward’s] pcb mill is as impressive as it is inexpensive. Twenty-six plywood parts, labeled A-Z, are used to assemble the machine along with the customary precision rods, stepper motors, and router assembly. His bill of materials prices the unit at $458.18, a small price to pay in order to forgo a multi-step etching process.

His test board shows some fairly fine pitch that could turn out most home-project circuit boards. We’ve contacted [Jonathan] regarding the specifics of milling the plywood parts out of a 2 foot by 4 foot sheet of plywood. Watch for an update with any information he’s willing to share. We hope he’ll make the milling files for the plywood parts available so that you can build a copy of the device for your own use.

[Thanks Charles]