IMU – Accelerometers and Gyroscopes
Accelerometers and Gyroscopes as well as combination IMU devices (Inertial Measurement Unit). The ADXL345 from Analog Devices is a small, thin, low power, 3-axis accelerometer with high resolution 13-bit measurement at up to ±16 g.
On the right the ADXL345, connected to the I2c-bus, and when connected well, you will find it in the I2c-scanner. This is the Bascom-AVR
code for the I2c-scanner. When the ADXL345 and the HMC5843 are fixed on the board you should see this in Hyperterminal.
This guide is intended to everyone interested in inertial MEMS (Micro-Electro-Mechanical Systems) sensors, in particular Accelerometers
and Gyroscopes as well as combination IMU devices (Inertial Measurement Unit).
FreeIMU – an Open Hardware Framework for Orientation and Motion Sensing. Ongoing research project which aims to design Open Hardware 9/10 DOM/DOF Inertial Measurement Units as well as easy to use Orientation and Motion Sensing libraries, built on top of the Arduino platform.
FreeIMU can be easily used on Arduino compatible boards using the Arduino FreeIMU library which implements sensor fusion MARG orientation filter enabling you to do easy and straightforward orientation sensing.
Communication procedure between the ADXL345 and the Arduino and then, between the Arduino and Processing
There are two ways to talk to the sensor, SPI and I2C protocols. I’ve chose the I2C (the schematics above are for I2C communication) because it is easier to wire for, and easier to code – the downside, they say, is that I2C is slower.