Wearable technology is finding inroads into vertical markets such as healthcare, industrial, and automotive sectors. For example, special vehicle-health applications that monitor fuel efficiency, automobile speed, and the heart rate of a fatigue driver are being developed by Nissan, BMW, and Mercedes automotive manufacturers. The cost of wearable technology development boards ranges from low cost to highly expensive. Adafruit has created a cost-effective wearable platform called the Flora were special electronic modules have been designed to work with the microcontroller-based maker board. In this article, I’ll explore the Flora’s system architecture using block, circuit schematic diagrams, and its printed circuit board design. Also, to illustrate the ease in prototyping wearable device concepts, I’ll provide a mini how-to guide on wiring and testing a GPS (Global Positioning System) module with the Flora.
|The Flora is a cost-effective platform to build wearable devices and technologies. (Source: Adafruit Industries)|
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The Flora System Architecture
In exploring the Adafruit Flora I found the wearable device to be made of several subcircuits wired to an 8-bit microcontroller mounted on a small circular PCB (Printed Circuit Board). An Atmel ATMEGA32 microcontroller provides the processing power for the Flora, providing six digital pins, two communication pins, and two serial control lines. These digital pins and control lines are accessible to makers, designers, and engineers by half circle solder pads that surround the Flora’s perimeter. In addition, a reset switch, mini USB, dual regulated power supply (3.3V/5V supplies), and three LEDs (transmit, receive, and power) complete the Flora’s system architecture.
|The system architecture block diagram of the Adafruit Flora. (Source: Don Wilcher)|
Adafruit has provided all of the Eagle Cad circuit schematic diagrams and PCB layout drawings for engineers, designers, and makers interested in experimenting with the mechanical packaging and electronic designs of the Flora on their github website.
|PCB and circuit schematic diagrams for the Flora. Electronic designs were created using Eagle Cad software. (Source: Adafruit Industries)|
The Ultimate GPS Module
Before discussing the prototyping specifics of the Flora-GPS wearable device, here’s a few technical specifications about the module. The Ultimate GPS module uses the MT3339 chipset manufactured by GlobalTop Technology company. This GPS module is capable of tracking 22 satellites using 66 channels, according to the Adafruit website. All of the electronics are packaged in a 4 mm x 15 mm x 15 mm small plastic box. The module is soldered to a small circular printed circuit board with soldered pads.
|The Ultimate GPS module uses a tiny satellite receiver chipset. The solder pads makes it easy to prototype wearable devices. (Source: robotshop.com)|
The soldered pads provide accessible power, TX (transmit), RX (receive) pins for experimenting and prototyping wearable device concepts with the Flora. A small ceramic patch antenna for receiving satellite data sits