IMU or Inertial Measurement Unit from POLOLU

The POLOLU-2739 module is a combination of a 3-axis gyroscope, 3-axis accelerometer, 3-axis magnetometer, and a digital barometer. They are embedded in a compact (12.7 mm by 25.4 mm), 2.54 mm pitch PCB circuit.

The POLOLU-2739, also known as AltIMU-10 (version 5), uses precise, highly miniaturized integrated circuits: LSM6DS33 (accelerometer and gyro carrier), LIS3MDL (3-axis magnetometer) and LPS25H (pressure gauge). These are the latest generation of MEMS (microelectromechanical systems), characterized by speed and precision of measurements. Unfortunately, their use in amateur projects (and even in the early stages of professional prototyping) is sometimes difficult due to their SMD casings and the 3.6V DC power supply, which is incompatible with popular platforms such as Arduino. The POLOLU-2739 contains a built-in logic level converter and voltage regulator/stabilizer, so that it can operate with a wider voltage range (from 2.5V to 5.5V DC).

POLOLU-2739

POLOLU-2739 position sensor

Functionalities include dynamically selectable sensitivities for the accelerometer, gyro and magnetometer, as well as adjustable barometer scale. All sensor functions are available via the shared I²C interface, so that with the help of two lines (clock and communication line) it is possible to use all components independently (addresses can be changed via a dedicated pin to avoid conflicts with other elements). Sensor data allows you to build an attitude and heading reference system (AHRS). In addition, the barometer readings can easily be processed; thus, it can act as an altimeter.

The POLOLU-2739 provides the functionality necessary to build a drone, aircraft, or RC helicopter. It will work in any application that requires constant detection of position changes. It is also an excellent educational platform – by providing multiple sensors in a single module it will make the first steps into robotics, remote control modelling and other challenging projects easier.