Basic components for building mHealth devices.

One step beyond the platform is adding other components. What do you create when your motto is “Computing stuff tied to the physical world?”  A tiny, fairly well featured kit with wireless capability. The JeeNode wireless communication platform.

It looks like a fun and cost effective way to get into experimenting with RF communication. By combining an Arduino-compatible processor (ATmega328) with a low-cost HopeRF radio module, Jean-Claude Wippler in a town called Houten, The Netherlands,  creates these building blocks and offering them for sale as a kit, or, since it is an open source hardware design, you can just download the PCB layout and roll your own. You can think of lots of applications (remote candle lighter, interactive cat toy:)) that aren’t worth a full xBee-based solution, where it would be handy to have a development board like this that I could just drop in and use.

Jee Labs also has a weblog with daily news about projects being worked on in the fascinating world of physical computing, wireless comm’s, sensors, lights, switches, motors, robots, WSN’s, Arduino’s, you name it.

Building a sensornetwork for mHealth purposes.

For a wireless sensor network you need a platform to start with. But what? Arduino is an open-source electronics prototyping platform based on flexible, easy-to-use hardware and software. It’s intended for artists, designers, hobbyists, and anyone interested in creating interactive objects or environments.

Arduino can sense the environment by receiving input from a variety of sensors and can affect its surroundings by controlling lights, motors, and other actuators. The microcontroller on the board is programmed using the Arduino programming language (based on Wiring) and the Arduino development environment (based on Processing). Arduino projects can be stand-alone or they can communicate with software on running on a computer (e.g. Flash, Processing, MaxMSP).

The boards can be built by hand or purchased preassembled. The software can be downloaded for free. The hardware reference designs (CAD files) are available under an open-source license, you are free to adapt them to your needs.

Wireless Sensor Networks and mHealth basics 1.

Building a Wireless Sensor Network is fine, but what are the unique characteristics of such a network:

• Limited power they can harvest or store
• Ability to withstand harsh environmental conditions
• Ability to cope with node failures
• Mobility of nodes
• Dynamic network topology
• Communication failures
• Heterogeneity of nodes
• Large scale of deployment
• Unattended operation
• Node capacity is scalable,only limited by bandwidth of gateway node.

Sensor nodes can be imagined as small computers, extremely basic in terms of their interfaces and their components. They usually consist of a processing unit with limited computational power and limited memory, sensors (including specific conditioning circuitry), a communication device (usually radio transceivers or alternatively optical), and a power source usually in the form of a battery. Other possible inclusions are energy harvesting modules, secondary ASICs, and possibly secondary communication devices (e.g. RS-232 or USB).

The base stations are one or more distinguished components of the WSN with much more computational, energy and communication resources. They act as a gateway between sensor nodes and the end user.