[Sigurd] manage to obtain an old vending machine from his dorm. The only problem was that the micocontroller on the main board was broken. He and his friend decided they could most likely get the machine back into working order, but they also knew they could probably give it a few upgrades.

This system uses two Arduino Pro Minis and an Electric Imp to cram in all of the new features. One Arduino is connected to the machine’s original main board. The Arduino interfaces with some of the shift registers, relays, and voltage regulators. This microcontroller also lights up the buttons on the machine as long as that particular beverage is not empty. It controls the seven segment LED display, as well as reading the coin validator.

The team had to reverse engineer the original coin validator in order to figure out how the machine detected and counted the coins. Once they figured out how to read the state of the coins, they also built a custom driver board to drive the solenoids.

A second Arduino is used to read NFC and RFID cards using a Mifare RC522 reader. The system uses its own credit system, so a user can be issued a card with a certain amount of pre-paid credit. It will then deduct credit appropriately once a beverage is vended. The two Arduinos communicate via Serial.

The team also wanted this machine to have the ability to communicate with the outside world. In this case, that meant sending cheeky tweets. They originally used a Raspberry Pi for this, but found that the SD card kept getting corrupted. They eventually switched to an Electric Imp, which worked well. The Arduino sends a status update to the Imp every minute. If the status changes, for example if a beverage was dispensed, then the Imp will send a tweet to let the world know. It will also send a tweet to the maintenance person if there is a jam or if a particular slot becomes empty.

[Connor] was working on a project for his college manufacturing class when he came up with the idea for this sleek desk lamp. As a college student, he’s not fond of having his papers glowing brightly in front of him at night. This lamp takes care of the problem by adjusting the color temperature based on the position of the sun. It also contains a capacities touch sensor to adjust the brightness without the need for buttons with moving parts.

The base is made from two sheets of aluminum and a bar of aluminum. These were cut and milled to the final shape. [Connor] found a nice DC barrel jack from Jameco that fits nicely with this design. The head of the lamp was made from another piece of aluminum bar stock. All of the aluminum pieces are held together with brass screws.

A slot was milled out of the bottom of the head-piece to make room for an LED strip and a piece of 1/8″ acrylic. This piece of acrylic acts as a light diffuser.  Another piece of acrylic was cut and added to the bottom of the base of the lamp. This makes for a nice glowing outline around the bottom that gives it an almost futuristic look.

The capacitive touch sensor is a pretty simple circuit. [Connor] used the Arduino capacitive touch sensor library to make his life a bit easier. The electronic circuit really only requires a single resistor between two Arduino pins. One of the pins is also attached to the aluminum body of the lamp. Now simply touching the lamp body allows [Connor] to adjust the brightness of the lamp.

[Connor] ended up using an Electric Imp to track the sun. The Imp uses the wunderground API to connect to the weather site and track the sun’s location. In the earlier parts of the day, the LED colors are cooler and have more blues. In the evening when the sun is setting or has already set, the lights turn more red and warm. This is easier on the eyes when you are hunched over your desk studying for your next exam. The end result is not only functional, but also looks like something you might find at that fancy gadget store in your local shopping mall.

Yesterday at Maker Faire Bay Area 2012 we visited the Electric Imp booth to chat with the startup's founders and get some hands-on time with the tiny wireless computer. What is the Electric Imp? It's a module containing an ARM Cortex M3 SoC with embedded WiFi that's built into an SD card form factor. While the device looks just like and SD card, it's not pin-compatible with the standard -- the idea is to leverage a reliable and affordable connector for the Electric Imp. The module is not very useful on its own -- it only comes to life when inserted into one of several boards, which provide the Electric Imp with power and access to the real world. In turn the device gives these boards a brain and an Internet connection. Eventually the company hopes that appliance manufacturers will incorporate Electric Imp slots into products to make them network aware.

We talked with CEO Hugo Fiennes (formerly with Apple) about the past, present and future of the Electric Imp so hit the break to read more and to watch our hands-on video.

Gallery: Electric Imp hands-on

Continue reading Hands-on with the Electric Imp at Maker Faire (video)

Hands-on with the Electric Imp at Maker Faire (video) originally appeared on Engadget on Mon, 21 May 2012 00:20:00 EST. Please see our terms for use of feeds.