Network Device with Bluetooth Sensors

Project overview

Our company was commissioned by Parrot (Paris) to develop a compact device for collecting data from Bluetooth sensors and transmitting them to the server. This new network device works with multiple Parrot Flower Power mobile gadgets that measure lighting, temperature, humidity, and soil fertility, helping users to create optimal conditions for growth and development of their plants.

The hardware platform of the device is based on the TI Sitara Cortex-A8 microcontroller and the Wi-Fi / Bluetooth 4.0 module. Software: Linux kernel, u-Boot, Qt and Bluez. Mobile applications for Apple iPhone (iOS) and Nexus (Android) smartphones have been developed to test the use of a BLE interface.

The enclosure designed features a stylish modern design, small size and high durability (it can withstand falling on concrete from a height of one meter).

The device has successfully passed pre-certification testing for impact resistance, air condition (0 ... + 40 ° C), safety in compliance with ETSI EN60950 2001, as well as radiated and conducted interference in compliance with EN 550022.

Bluetooth Smart Gateway features:

  • No analogues (it works with Parrot trademark sensors)
  • No external Wi-Fi antenna (PCB-embedded)
  • Low power consumption: about 1 watt per hour
  • BLE interface support
  • Power supply via micro USB

Project outcome

Promwad experts completed the following tasks under the project:

  • Hardware platform design
  • Software development
  • Enclosure construction development
  • Manufacturing of prototypes
How It's Made

Solution

1. Hardware

The main hardware components: Wi-Fi / Bluetooth 4.0 module; TI Sitara Cortex-A8 microcontroller; DDR3 128 MB; NAND Flash 128 MB.

Figure 2. A block diagram of the device  


Figure 3. The front side of the printed circuit board

 


2. Software

The device uses the following software:

  • Linux kernel 3.12
  • u-Boot 2013.04
  • Qt 4.8
  • Bluez 5.21

To test the interaction of mobile platforms with the device through the BLE interface, two mobile applications have been developed

  • A mobile application for Apple iPhone operated by iOS7
  • A mobile application for Nexus phone operated by Android 4.4

 


3. Enclosure design

A compact enclosure with a modern design has been developed for the device. The enclosure features:

  • A rather thin device
  • Shock resistant (it can withstand falling on a concrete floor from a height of 1 m)

Figure 4. Enclosure: side view

 


4. Pre-certification testing

After a prototype was developed, the device successfully passed the following tests:

  • Impact test (the device was thrown on a concrete floor from a height of 1 meter)
  • Environmental testing at a temperature of 0 to 40 degrees Celsius
  • Safety testing: the device has been tested for compliance with ETSI EN60950 2001 1.6-1.7, 2.1-2.10, 3.1-3.5, 4.2, 4.3, 4.5, 5.1-5.3
  • Radiated emissions testing: compliance with EN 55022 6.2. Testing in the frequency range of 30 MHz to 1 GHz and 1 GHz to 6 GHz with a 1 MHz spacing
  • Conducted interference testing in compliance with EN 550022

 


Advantages

  • No rivals: the device is created to collect data from Parrot’s Bluetooth sensors
  • Low power consumption: about 1 watt per hour
  • Access to the sensors through the BLE interface
  • Since there is no external Wi-Fi antenna, this helps save on the cost of electronic components for mass production (the antenna is soldered directly to the PCB)
  • Modern and compact design
  • Shock resistance (falling on concrete from a height of 1 m)
  • Power supply via micro USB connector