Embedded World: basketball, Bluetooth and the IoT
The latest version of Bluetooth has seen an explosion in innovative and interesting fitness applications, writes Mark Zack, v-p global semiconductors, Digi-Key.
Imagine a Bluetooth-enabled basketball that tracks all the moves in your game or a Bluetooth-enabled tennis racket that monitors your swing to help you improve.
With Bluetooth Smart, all kinds of equipment has suddenly, and perhaps surprisingly, become connected.
This is just the first stage. Bluetooth Low Energy (BLE) has enabled a wide range of wireless transceiver modules that can be easily added to equipment. With the smartphone at the other end, there is a ready-made terminal and control software available to everyone through the App Store or Google Play.
Now the next iteration of Bluetooth Smart, version 4.1, adds capabilities that allow one smartphone to link to a network of devices, rather than just one. Moreover, this opens up previously passive consumer and industrial everyday equipment to the internet of things (IoT).
The internet of things means a lot of different things to a lot of different people. There may be billions of devices (maybe 30 billion, maybe 50 billion, depending on your fortune teller of choice) connecting together, and behind the scenes, the Bluetooth Special Interest Group has been learning from other network technologies to produce an easy to use low power specification for a network of devices.
Imagine if your electric toothbrush becomes connected to your smartphone – you can tell whether the kids have brushed their teeth this morning, if it needs a new head, or even download the latest new brushing technique.
Connecting up and controlling your TV, stereo, oven, refrigerator, air conditioning, security system and any other home system becomes quick and easy. The opportunities for new ways to make life easier are endless. The same applies for connecting heating and cooling systems in offices and factories, linking and easily controlling all manner of equipment.
Key to Bluetooth Smart 4.1 is that it allows devices to support multiple roles simultaneously, so that a Bluetooth Smart Ready product can act as a hub and a peripheral at the same time. The coexistence with other wireless technologies, notably Wi-Fi on the same 2.4GHz band, has been improved, and dedicated channels have been added for IoT applications.
This Logical Link Control and Adaptation Architecture (L2CAP) supports higher-level protocol multiplexing, packet segmentation and reassembly, and quality of service information with 64kbyte packets.
The architecture is based around channels where each endpoint has a channel identifier (CID). The CID assignment is relative to a particular device and a device can assign CIDs independently from other devices, making it easy to add devices to a network.
There are many modules now available from manufacturers such as Laird Wireless, connectBlue and BlueGiga that support the current 4.0 version of the specification. Dropping these into existing designs – from basketballs to fitness devices – has given industrial and consumer designers confidence to move quickly.
Many different wireless technologies vying to be part of the internet of things, and they all have their place. However, Bluetooth holds a trump card by being part of every current smartphone, providing a ready-made, low power, high performance terminal.
The Bluetooth-enabled basketball is just the start. Just wait for the connections we will make in the home, office, and factory floor.
Mark Zack, v-p global semiconductors, Digi-Key