- EOL
Attention! Product replaced by a new version:AltIMU-10 v3 gyroscope, accelerometer, compass and altimeter. |
Specification .
- Power supply voltage: 2.5 V - 5.5 V
- Power consumption: 10 mA
- Three axes: X, Y, Z
- Communication interface: I2C (TWI)
- Data format:
- Accelerometer: 12 bits per axis (aligned to the left)
- Gyroscope: 16-bit per axis
- Magnetometer: 12 bitsper axis (aligned to the left)
- Barometer: 24 bits(4096 LSb/mbar)
- Measurement ranges (configurable):
- Accelerometer: ±2, ±4, ±8, ±16 g
- Gyroscope: ±250, ±500, ±2000 °/s
- Barometer: 26 kPa - 128 kPa
- Magnetometer: ±1.3, ±1.9, ±2.5, ±4.0, ±4.7, ±5.6, ±8.1 gauss
- Size: 25.4 x 12.7 x 2.5 mm
- Weight: 1 g (without connectors)
Description
AltIMU-10 module is a 3-axis accelerometer, 3-axis magnetometer (LSM303), 3-axis gyroscope (L3GD20) and barometer (LPS331).With these sensors it is possible to create a complete AHRS (attitude and heading reference system), i.e. to determine the position of an object in three-dimensional space. Data from the barometer are easily converted to height, the gyroscope allows to track the rotation of the object and the accelerometer together with the magnetometer compensate the gyroscope drift and determine the absolute reference point.
All sensors communicate digitally via the I2C bus. The module has a voltage regulator and the necessary passive elements. The leads are the popular goldpin connectors, which allow the sensor to be connected bywires ordirectly connected to the contact plate.
AltIMU-10 is pin-compatible with MinIMU-9 v2 module. It has the same functions with the addition of a digital barometer that can be used as a height sensor. Correctly written code for MinIMU-9 v2 will work with AltIMU-10.
Arduino compatible product The manufacturer has prepared libraries for the L3G gyroscope, LSM303accelerometerandLPS331barometer, whichallowfor simple sensor operation with Arduino. |
Sample programme
In order to show the capabilities of the IMU module, a sample program for Arduino is available. It uses data from AltIMU-10 to determine coordinates in three axes X, Y, Z to visualize the object in 3D space, as shown in the figures above. The software is based on a project by Jordi Munoz, William Premerlani, Jose Julio and Doug Weibel.
Visualization of an object in 3D space.
Visualization of the object in 3D.
The sensor has five goldpin connectors - 2.54mm raster (included).
PIN |
Description |
SCL | I2C bus clock line. The high state is equal to the VIN voltage. Low GND. |
SDA | I2C bus data line. High state equals VIN voltage. Low GND. |
GND | System mass potential |
VIN | Supply voltage from 2.6V to 5.5V |
VDD | If the supply voltage is higher than 3.3V, the output can serve as a 3.3V output with a current capacity up to 150mA. When the power supply voltage is in the range of 2.5V - 3.3V, connect it to the VDD output. |
I2C addressing
The accelerometer, magnetometer, gyroscope and barometer, located in the module, have 7-bit addresses. They are set to the appropriate address:
- Accelerometer LSM303DLHC - 0011001b
- Magnetometer LSM303DLHC- 0011110b
- Gyroscope L3GD20-1101011b
- Barometer LPS331AP-1011101b
The bus works correctly at 400MHz, higher values may work correctly but have not been tested.
First-time use instructions
All necessary information on communication and sensor handling of the AltIMU-10 can be found inthe documentation ofeach sensor. Below are some of the most important facts:
- The pressure sensor, accelerometer and gyroscope are disabled by default. They should be activated by setting the appropriate bits in the respective registers.
- It is possible to multi-read and multi-record the accelerometer, gyroscope and barometer by means of a single I2C command by setting the most significant address bit (starting self-increment).
- The pressure sensor (barometer) has data in 24-bit format. The accelerometer, magnetometer and gyroscope transmit 16-bit words, but only the gyroscope data is 16-bit, the other two sensors have a maximum 12-bit precision.
- By default, the accelerometer works with a resolution of 10 bits. To use the full 12-bit precision, set the HR bit in the CTRL_REG4_A register.
- LSM303DLHC sensor is a combination of accelerometer and magnetometer (compass) in one chip. Both devices have different I2C bus addresses.
Visualization of orientation in space based on readings from the IMU module.
Dimensions
The system is small in size, its outline fits into a rectangle of dimensions: 25.4 x 12.7 mm. The assembly is done with a 2.18mm internal diameter hole.
Diagram
The system includes, among others, voltage stabilizers, filtering capacitors, pull-up resistors (e.g. I2C bus lines) and other passive elements facilitating the use of IMU sensors.
Useful links |