IMU Interface

Connected to NUCLEO-H745ZI-Q

Use all 4 pins; Vin(3.3V), GND(Ground), SDA(I2C), SCL(I2C) directly connected to the board according to the PIN specified in STM32CubeIDE

Prepare before STM32CubeIDE

Before starting to work in STM32CubeIDE, we need to prepare a library for using BNO055 and sending values ​​to ROS2 with the following step:

BNO055 with STM32CubeIDE

We will use STM32CubeIDE to use BNO055 and send values ​​on ROS2 by following steps.

  1. Create an STM32CubeIDE Project with board selected as NUCLEO-H745ZI-Q and set the file to C

  2. TIM1 and I2C1 pins are enabled with the following settings.

    ../_images/imu_interface1.png ../_images/imu_interface2.png ../_images/imu_interface3.png ../_images/imu_interface4.png ../_images/imu_interface5.png ../_images/imu_interface6.png ../_images/imu_interface7.png ../_images/imu_interface8.png

  3. Generate code from IOC

  4. Place the bno055.c file in the Src folder, bno055.h, bno055_stm32.h in Inc folder

    ../_images/imu_interface9.png

  5. Within main.c can be written and within file bno055_stm32.h delete the line #include “i2c.h” (will not delete if STM32 Project Generate Peripheral file comes out or we check the option as below picture in .ioc file)

    ../_images/imu_interface10.png

  6. Build and Upload to board

  7. Continue in ROS2 Interface

Implemention (Core M7)

// BNO055 Read Raw IMU Data
bno055_vector_t v = bno055_getVectorQuaternion();
qw = v.w;
qx = v.x;
qy = v.y;
qz = v.z;
v = bno055_getVectorLinearAccel();
ax = v.x;
ay = v.y;
az = v.z;
v = bno055_getVectorGyroscope();
gx = v.x;
gy = v.y;
gz = v.z;

Runtime Test

  • IMU Initialization

runstarttime = micros();
//***********************************************
bno055_assignI2C(&hi2c1);
bno055_setup();
bno055_setOperationModeNDOF();
//***********************************************
runtime = micros() - runstarttime;

Runtime: 739.833 - 741.696 ms

  • IMU Read Raw Data

runstarttime = micros();
//***********************************************
bno055_vector_t v = bno055_getVectorQuaternion();
qw = v.w;
qx = v.x;
qy = v.y;
qz = v.z;
v = bno055_getVectorLinearAccel();
ax = v.x;
ay = v.y;
az = v.z;
v = bno055_getVectorGyroscope();
gx = v.x;
gy = v.y;
gz = v.z;
//***********************************************
runtime = micros() - runstarttime;

Runtime: 3.980 - 7.463 ms