The robotic troika of Atmel summer interns in Trondheim

Troika: A Russian word for a group of three, and also a pretty good Norwegian chocolate bar.

It’s a safe assumption that most of us have had some sort of experience with summer jobs throughout our years as students. It’s also quite likely that some of us remember these jobs as full of sweat and manual work at a construction site, on a farm or in some kind of warehouse; however, not all summer jobs have to be this way. Today, I received a piece of mail from some of the summer interns at Atmel Trondheim, and from the sounds of it, they have some pretty cool things going on!

The Line Follower

A line follower is a machine equipped with some sort of light-sensitive sensors that follows a line — either a black line on a white surface or vica versa.

“This project utilizes two Light Dependent Resistors (LDRs) to detect the amount of reflected light from two Light Emitting Diodes (LEDs). The chassis is made of cardboard and the whole robot is made without any soldering. The idea behind this robot was to introduce some intelligence to a robot in an easy and inexpensive way,” explains Magne Normann, one of the summer interns at Atmel.

The Avoidance Robot

This is an obstacle avoidance-type robot based around the Atmel Abot. All that’s required to build this kind of robot is a platform, two motors/servos, some wires and a distance sensor. However, this particular project has got an additional servo. The ultrasonic sensor is mounted on a servo in front of the robot, and as the servo rotates, the sensor measures the distances in its envorionment and uses this information to choose a path between any obstacles.

The Atmel Tank

Have you ever seen one of those USB rocket launchers and wondered if they’re hackable? Well, they are.

“We got our hands on a USB missile launcher, disassembled it, did a reversed engineering and modified it. Then we added Bluetooth connectivity, put it on an Atmel Abot and made an app for it. The app does have both one and two-player modes; one player controls both the vehicle and the turret, and two-player mode where one player controls the car, while another controls the turret,” Magne shares.  

“Up until now the only way to interface with an USB rocket launcher had been through the complicated USB protocol. Unfortunately not many microcontrollers support this feature. We therefore decided to hack the rocket launcher down to the old school way, so we could control it with simple GPIOs. We opened the launcher up and discovered the unused footprint for a microcontroller. Apparently, initial design was based on using a microcontroller, but somewhere along the way someone decided to go with a die instead. This left the microcontroller pads unused and available for us to use. All we had to do was probe the signals for each command, disconnect the die from the circuit paths and solder our own wires to the microcontroller pads. This way we could use the existing H-bridges and switches without any additional hardware required.”

Magne notes that the tank is currently bringing havoc to the Atmel department located at Tiller, Norway. Interested in seeing it for yourself? The tank will be on display, along with several other Atmel-based projects, at Maker Faire Trondheim scheduled for August 29-30th. Maker Faire attendees will also have the opportunity to compete for the title of Maker Faire’s “Best Tank Commander.”

 

 

 

High voltage edge-lit TV topologies with Atmel

Bits & Pieces has been getting up close and personal with Atmel’s versatile lighting (MCU) portfolio in recent weeks. First, we took a look at the role Atmel MCUs (microcontrollers) have to play in brightening LED ballasts, highlighting the AVR AT90PWM microcontroller which supports the DALI standard and is used to network multiple ballasts to a centralized system for tighter light level control and significant energy savings.

We’ve also talked about how Atmel MCUs are used to light up both fluorescent and HID ballasts, as well as drive television direct backlights. And today we’ll be discussing high voltage edge-lit TV topologies. Specifically, edge-lit configurations use external power supplies and NFETs to allow voltage power supplies to drive a larger number of LEDs (72 LEDs) per string and can sink up 1A (determined by NFET ratings).

“Atmel LED drivers are capable of driving up to 16 parallel strings of LEDs, all while offering fault detection and management of open-circuit and short-circuit LEDs,” an Atmel engineering rep told Bits & Pieces.

“These devices address the edge-lit and high-brightness LEDs which require higher power while enabling dimming via external pulse width modulation (PWM) signals or analog current control with an internal digital-to-analog converter (DAC).”

In addition, the engineering rep noted that edge-lit topologies are the most popular backlight architectures in current LCD television applications because they are less expensive (requires fewer LEDs) compared to direct-backlight topologies.

“Edge-lit designs are also capable of offering zone (regional) dimming but are limited to larger tiles (coarse zones) and require expensive diffusers which use light guides to distribute light to desired zones,” the engineering rep continued.

“Edge-lit applications require an external DC-to-DC supply to boost the supply up to 250V to allow 72 LEDs per string. Television manufactures also implement LED string phase shift to reduce the overall RMS power requirements and minimize EMI noise by effectively driving one LED string at a time within a frame time period.”

Interested in learning more about high voltage edge-lit TV topologies with Atmel? Be sure to check out our official device breakdown page here.