[Travis Brown] just published a post about the traffic light controller he built. His number one goal was to make the device wireless (except for AC power) and he achieved this by using a WiFi shield for his Arduino. But there is also a separate board that provides a way for the chip to switch the AC lights.

He works for a web hosting company, and the boss wanted a fun way to display the status of the servers among other things. He chose to use the WiServer library which controls the CoperHead WiFi Shield and gives him the ability to serve simple web pages from the Arduino. When power is applied the sketch automatically connects to the AP and starts polling the company’s API for status data. If you’re not within eyesight of the traffic lights you can log into the web server and check that way.

We think [Travis] did a great job of explaining his code, and we applaud him for making proper use of the watchdog timer (something we don’t see in very many projects). This joins the pile of traffic-light display devices we’ve seen around here. We still don’t know where people are getting their hands on the things.

[Andy] needed a cheap Internet connection between a data-gathering Arduino and his home server. An Ethernet shield would suffice, but he couldn’t run CAT5 to the Arduino’s location. Wireless shields are hideously expensive, and after looking over the popular Zigbee modules, [Andy] had a few concerns about range and build complexity.

The obvious solution to this problem was getting a cheap WiFi router, flashing OpenWRT firmware on the device, and piping sensor data through the Arduino’s USB port, through the router, and over a WiFi connection to the server.

[Andy] used a TP-Link TL-WR703N wireless ‘travel router’ available on eBay £15 (~$30 USD when we checked). After flashing the router with OpenWRT, [Andy] had a wireless connection from a remote data-collecting Arduino directly to his server.

Attentive Hack a Day readers will note this is the third ‘wireless router + OpenWRT as a dev board’ build this week (first one, second one) . No, we don’t know what’s going on, or why the collective unconscious of makers around the globe decided to latch onto this type of build so suddenly. OpenWRT is available for hundreds of different routers, and anything that keeps disused routers out of the landfill (with the bonus of doing something useful) is alright in our book, so if you have another similar build, send it in and we’ll get around to it sometime.

Sure, we see hexapods all the time at [HAD], but moving around with four legs can be more tricky kinematics-wise. This Instructable shows you how to make one out of balsa wood.

Although one might not think of balsa to make their robot out of [vexedpheonix] explains that this was chosen because it’s extremely light and easy to work with. Since he was trying to keep costs down, the cheapest servos available were used. These weren’t all that powerful, so the lighter the body the better! According to the included bill of materials, he was able to keep the entire robot build under $100.

According to the article, the hardest part was making four copies of the same leg. We might suggest using a CNC router, but building one would obviously add a huge layer of complication to the project!

Thanks for the tip on this one [SteveT]! Be sure to check out the video of this little robot waving one of it’s legs or trying to walk after the break!

If you’d rather see a hexapod in action, why not check out this one!