stream_imu

7 Series IMU Streaming Example (C++)

This example demonstrates how to stream basic IMU sensor data from a MicroStrain 7-series device with the MIP SDK using the C++ API.

Overview

The example showcases basic IMU sensor data streaming setup and operation of a 7-series device, including:

• Device initialization and communication
• Sensor message format configuration
• Real-time data streaming and display
• Dynamic magnetometer support detection (device feature check)
• Basic packet and field-level callbacks

Configurable Options

The example uses the following default settings, which should be adjusted based on application requirements:

Setting	Value	Description
PORT_NAME	"COM1" (Windows) "/dev/ttyACM0" (Unix)	Serial port for device communication
BAUDRATE	115200	Communication baud rate
SAMPLE_RATE_HZ	1	Data output rate in Hz
RUN_TIME_SECONDS	30	Example runtime duration

Usage

1. Connect your 7-series device to the specified serial port
2. Update the configuration options based on your application needs
3. Compile and run the example
4. The program will:
   • Initialize the device and query supported descriptors
   • Configure data streaming
   • Register callbacks for data processing
   • Stream data for the specified runtime
   • Display real-time sensor data
   • Clean up and exit

Building

With CMake (Recommended)

The project can be configured on its own using the supplied CMakeLists.txt. The file is configured to work directly in the MIP SDK project or as a standalone project. If building outside the MIP SDK project, all that's needed is to define MIP_SDK_ROOT_DIR. When building within the MIP SDK project, make sure to enable the examples using the MICROSTRAIN_BUILD_EXAMPLES CMake option.

Standalone Command Line

mkdir build
cd build
cmake .. -DMIP_SDK_ROOT_DIR:PATH=<path_to_mip_sdk>

Without CMake

If the project cannot be configured using CMake, then the following project configurations are required:

Required Libraries

Link against these libraries:

• mip - Core MIP SDK library
• microstrain - Core MicroStrain SDK library
• microstrain_serial - MicroStrain serial communication library

Make sure to include those library paths as additional link directories if needed

Include Directories

Add these include directories:

• [path_to_mip_sdk_include]/c
• [path_to_mip_sdk_include]/cpp
• [path_to_project_root]

path_to_mip_sdk_include can be installed paths or source paths:

• Unix - /usr/include/microstrain
• Windows - C:/Program Files/MIP_SDK/include/microstrain
• Source: [mip_sdk_project_root]/src

Compiler Definitions

Add these compiler definitions:

• MICROSTRAIN_LOGGING_MAX_LEVEL=MICROSTRAIN_LOGGING_LEVEL_INFO_ Sets the logging level to info which is the minimum required for this example

Key Functions

Device Setup

• initializeDevice() - Establishes communication, validates device connection, and loads defaults
• isDescriptorSupported() - Checks device capabilities for supported data types

Message Configuration

• configureSensorMessageFormat() - Configures IMU sensor data output including:
  • Scaled accelerometer
  • Scaled gyroscope
  • Scaled magnetometer (if supported)

Data Processing

• packetCallback() - Processes complete MIP packets and displays field information
• accelFieldCallback() - Handles accelerometer data fields
• gyroFieldCallback() - Handles gyroscope data fields
• magFieldCallback() - Handles magnetometer data fields (if supported)

Communication Interface

• Uses the mip::Interface class for device communication
• Serial connection handled by microstrain::connections::SerialConnection

Data Handling

This example uses modern C++ features including:

• Data Extractors: Automatic parsing of incoming data fields
• Type Safety: Strongly typed data structures for each message type
• Callbacks: Automatic data callbacks for registered message types
• String Handling: Safe C++ string operations

C++ Implementation Features

This example demonstrates:

• MIP Interface: Modern C++ interface for device communication (mip::Interface)
• Modern C++ Connection Management: RAII-based resource handling
• Type-Safe MIP Command Interfaces: Compile-time type checking
• Exception Safety: Proper error handling and resource cleanup
• STL Integration: Use of standard library containers and algorithms
• Portability: Cross-platform compatibility (Windows/Unix)

Connection Management

This example uses modern C++ connection handling:

• SerialConnection: RAII-based serial connection management
• Automatic Cleanup: Connection automatically closed when the object goes out of scope

IMU Sensor Data Output

The example streams the following IMU sensor data:

Accelerometer Data

• Units: g (gravitational acceleration)
• Range: Device-dependent (typically ?2g, ?4g, ?8g, ?16g)
• Format: [X, Y, Z] scaled acceleration vector

Gyroscope Data

• Units: rad/s (radians per second)
• Range: Device-dependent (typically ?250?/s to ?2000?/s)
• Format: [X, Y, Z] scaled angular rate vector

Magnetometer Data (if supported)

• Units: Gauss
• Range: Device-dependent
• Format: [X, Y, Z] scaled magnetic field vector
• Note: Automatically detected and configured if available

Streaming Output Format

The example displays sensor data in the following format:

Scaled Accel Data (0x80, 0x04): [ 0.012345, -0.098765,  0.987654]
Scaled Gyro Data  (0x80, 0x05): [-0.001234,  0.005678, -0.002345]
Scaled Mag Data   (0x80, 0x06): [ 0.123456, -0.234567,  0.345678]

Error Handling

The example includes comprehensive error handling with:

• Command result checking using mip::CmdResult
• Connection failure detection and recovery
• Graceful termination functions for different error types
• Detailed error messages with context using built-in documentation strings

C++ Features

This example demonstrates:

• Modern C++ connection management
• Type-safe MIP command interfaces
• Automatic data field extraction
• RAII resource management
• Standard library integration

Type Safety and Documentation

This example provides additional C++ benefits:

• Built-in Documentation: Data structures include DOC_NAME constants for easy reference
• Strongly Typed Enums: C++ enum classes prevent accidental misuse
• Automatic Descriptors: DESCRIPTOR constants eliminate magic numbers

Requirements

• MicroStrain 7-series device
• Serial connection (USB or RS-232)
• MIP SDK library with C++ support
• C++11 or later compiler

See Also

• C version: 7_series_stream_imu_example.c
• Other examples in the examples/ directory
• MIP SDK documentation