Category Archives: Arduino

Adafruit BNO055 9-axis Sensor Connected to an Arduino Nano

This lesson shows you some of the simple math, that will allow you to approximate tilt angle from a three axis accelerometer. In this entire series of lessons, we are using the BNO055 9-axis sensor connected to an Arduino Nano. It is possible to approximate tilt along the x-axis and tilt along the y-axis. These could roughly be considered to be like the Euler Angles of Pitch and Roll. It should be noted that the approximations are reasonable for tilt angles less than 45 degrees. Also note, that in this simple demonstration, real acceleration will be interpreted as tilt, hence the system will incorrectly interpret motion as tilt. Because of this, this approach should not be used on things like drones or other moving systems. It is just for simple demonstration purposes.

The code developed in the video above is included below for your convenience.

The code below is for demo purposes only, and should not be used in any real applications. It just demonstrates how to work with this sensor in benchtop presentations.

#include <Wire.h>
#include <Adafruit_Sensor.h>
#include <Adafruit_BNO055.h>
#include <utility/imumaths.h>
#include <math.h>
float theta;
float phi;
#define BNO055_SAMPLERATE_DELAY_MS (100)

Adafruit_BNO055 myIMU = Adafruit_BNO055();

void setup() {
  // put your setup code here, to run once:
Serial.begin(115200);
myIMU.begin();
delay(1000);
int8_t temp=myIMU.getTemp();
myIMU.setExtCrystalUse(true);
}

void loop() {
  // put your main code here, to run repeatedly:
uint8_t system, gyro, accel, mg = 0;
myIMU.getCalibration(&system, &gyro, &accel, &mg);
imu::Vector<3> acc =myIMU.getVector(Adafruit_BNO055::VECTOR_ACCELEROMETER);
theta=-atan2(acc.x()/9.8,acc.z()/9.8)/2/3.141592654*360;
phi=-atan2(acc.y()/9.8,acc.z()/9.8)/2/3.141592654*360;
Serial.print(acc.x()/9.8);
Serial.print(",");
Serial.print(acc.y()/9.8);
Serial.print(",");
Serial.print(acc.z()/9.8);
Serial.print(",");
Serial.print(accel);
Serial.print(",");
Serial.print(gyro);
Serial.print(",");
Serial.print(mg);
Serial.print(",");
Serial.print(system);
Serial.print(",");
Serial.print(theta);
Serial.print(",");
Serial.println(phi);


 
delay(BNO055_SAMPLERATE_DELAY_MS);
}

#include <Wire.h>

#include <Adafruit_Sensor.h>

#include <Adafruit_BNO055.h>

#include <utility/imumaths.h>

#include <math.h>

float theta;

float phi;

#define BNO055_SAMPLERATE_DELAY_MS (100)

Adafruit_BNO055 myIMU = Adafruit_BNO055();

void setup() {

// put your setup code here, to run once:

Serial.begin(115200);

myIMU.begin();

delay(1000);

int8_t temp=myIMU.getTemp();

myIMU.setExtCrystalUse(true);

}

void loop() {

// put your main code here, to run repeatedly:

uint8_t system, gyro, accel, mg = 0;

myIMU.getCalibration(&system, &gyro, &accel, &mg);

imu::Vector<3> acc =myIMU.getVector(Adafruit_BNO055::VECTOR_ACCELEROMETER);

theta=-atan2(acc.x()/9.8,acc.z()/9.8)/2/3.141592654*360;

phi=-atan2(acc.y()/9.8,acc.z()/9.8)/2/3.141592654*360;

Serial.print(acc.x()/9.8);

Serial.print(",");

Serial.print(acc.y()/9.8);

Serial.print(",");

Serial.print(acc.z()/9.8);

Serial.print(",");

Serial.print(accel);

Serial.print(",");

Serial.print(gyro);

Serial.print(",");

Serial.print(mg);

Serial.print(",");

Serial.print(system);

Serial.print(",");

Serial.print(theta);

Serial.print(",");

Serial.println(phi);

delay(BNO055_SAMPLERATE_DELAY_MS);

}

Arduino, Tutorial

Arduino Tutorial 28: Using a Pushbutton as a Toggle Switch

September 17, 2019 admin

In lesson 27 we learned how to incorporate a pushbutton into an arduino project. We learned how to utilize pull-up and pull-down resistors in order to incorporate a button into a circuit. The operation of the button in lesson 27 was pretty simple . . . if the button was held down, the LED would come on. When the button was released, the LED would turn back off. This is an interesting demonstration, but much more interesting is the case where we make a toggle switch. If you press and release the button, the LED comes on, and then if you press and release the button again, the LED goes off. While this sounds very similar to the previous case, it turns out to require a lot more thought. This video lesson explains how to think about this problem, and how to make it work.

If you want to follow along at home, you can order the Arduino Kit we are using HERE.

Below is the code we used to achieve the toggle operation. The video gives details on how to connect up the circuit.

int LEDState=0;
int LEDPin=8;
int buttonPin=12;
int buttonNew;
int buttonOld=1;
int dt=100;

void setup() {
  // put your setup code here, to run once:
Serial.begin(9600);
pinMode(LEDPin, OUTPUT);
pinMode(buttonPin, INPUT);

}

void loop() {
buttonNew=digitalRead(buttonPin);
if(buttonOld==0 && buttonNew==1){
  if (LEDState==0){
    digitalWrite(LEDPin,HIGH);
    LEDState=1;
  }
  else{
    digitalWrite(LEDPin, LOW);
    LEDState=0;
  }
}
buttonOld=buttonNew;
delay(dt);
}

int LEDState=0;

int LEDPin=8;

int buttonPin=12;

int buttonNew;

int buttonOld=1;

int dt=100;

void setup() {

// put your setup code here, to run once:

Serial.begin(9600);

pinMode(LEDPin, OUTPUT);

pinMode(buttonPin, INPUT);

}

void loop() {

buttonNew=digitalRead(buttonPin);

if(buttonOld==0 && buttonNew==1){

if (LEDState==0){

digitalWrite(LEDPin,HIGH);

LEDState=1;

}

else{

digitalWrite(LEDPin, LOW);

LEDState=0;

}

buttonOld=buttonNew;

delay(dt);

}

Arduino, Arduino 9-Axis IMU Totorials

9-Axis IMU LESSON 5: Calibrating the BNO055 9-axis Inertial Measurement Sensor

September 12, 2019 admin

BNO055 IMU — Our 9-axis BNO055 9-axis sensor connected to our Aurduino Nano

In this lesson we show you how to get a clean calibration on your BNO055 9-axis sensor. In the video below we take you through the coded needed to calibrate the sensor, and a simple technique to quickly get the system properly calibrated.

The code developed in this video will be used in future lessons, and is included below:

The code below is for demo purposes only, and should not be used in any real applications. It just demonstrates how to work with this sensor in benchtop presentations.

#include <Wire.h>
#include <Adafruit_Sensor.h>
#include <Adafruit_BNO055.h>
#include <utility/imumaths.h>

#define BNO055_SAMPLERATE_DELAY_MS (100)

Adafruit_BNO055 myIMU = Adafruit_BNO055();

void setup() {
  // put your setup code here, to run once:
Serial.begin(115200);
myIMU.begin();
delay(1000);
int8_t temp=myIMU.getTemp();
myIMU.setExtCrystalUse(true);
}

void loop() {
  // put your main code here, to run repeatedly:
uint8_t system, gyro, accel, mg = 0;
myIMU.getCalibration(&system, &gyro, &accel, &mg);
imu::Vector<3> acc =myIMU.getVector(Adafruit_BNO055::VECTOR_ACCELEROMETER);


Serial.print(acc.x());
Serial.print(",");
Serial.print(acc.y());
Serial.print(",");
Serial.print(acc.z());
Serial.print(",");
Serial.print(accel);
Serial.print(",");
Serial.print(gyro);
Serial.print(",");
Serial.print(mg);
Serial.print(",");
Serial.println(system);

 
delay(BNO055_SAMPLERATE_DELAY_MS);
}

#include <Wire.h>

#include <Adafruit_Sensor.h>

#include <Adafruit_BNO055.h>

#include <utility/imumaths.h>

#define BNO055_SAMPLERATE_DELAY_MS (100)

Adafruit_BNO055 myIMU = Adafruit_BNO055();

void setup() {

// put your setup code here, to run once:

Serial.begin(115200);

myIMU.begin();

delay(1000);

int8_t temp=myIMU.getTemp();

myIMU.setExtCrystalUse(true);

}

void loop() {

// put your main code here, to run repeatedly:

uint8_t system, gyro, accel, mg = 0;

myIMU.getCalibration(&system, &gyro, &accel, &mg);

imu::Vector<3> acc =myIMU.getVector(Adafruit_BNO055::VECTOR_ACCELEROMETER);

Serial.print(acc.x());

Serial.print(",");

Serial.print(acc.y());

Serial.print(",");

Serial.print(acc.z());

Serial.print(",");

Serial.print(accel);

Serial.print(",");

Serial.print(gyro);

Serial.print(",");

Serial.print(mg);

Serial.print(",");

Serial.println(system);

delay(BNO055_SAMPLERATE_DELAY_MS);

}

Arduino, Tutorial

Arduino Tutorial 27: Understanding Pushbuttons and Pull Up and Pull Down Resistors

September 10, 2019 admin

Being able to add push buttons to your projects adds important new capabilities to your prototypes. It is a clever way you can get input from a user. You could imagine using push buttons to turn something on or off, or they could be used to set motor speed or direction. In order to incorporate buttons into a project, you need to understand the concept of pull up and pull down resistors. In this tutorial we show you how to include buttons in a project, by demonstrating a simple on/off function on an LED.

If you want to follow along at home, you can order the Arduino Kit we are using HERE.

This is the code we used in this project to switch the LED on and off.

int LEDPin=8;
int buttonPin=12;
int buttonRead;
int dt=100;
void setup() {
  // put your setup code here, to run once:
Serial.begin(9600);
pinMode(LEDPin, OUTPUT);
pinMode(buttonPin, INPUT);
}

void loop() {
  // put your main code here, to run repeatedly:
buttonRead=digitalRead(buttonPin);
Serial.println(buttonRead);
delay(dt);
if(buttonRead==1){
  digitalWrite(LEDPin,LOW);
}
if(buttonRead==0){
  digitalWrite(LEDPin, HIGH);
}

}

int LEDPin=8;

int buttonPin=12;

int buttonRead;

int dt=100;

void setup() {

// put your setup code here, to run once:

Serial.begin(9600);

pinMode(LEDPin, OUTPUT);

pinMode(buttonPin, INPUT);

}

void loop() {

// put your main code here, to run repeatedly:

buttonRead=digitalRead(buttonPin);

Serial.println(buttonRead);

delay(dt);

if(buttonRead==1){

digitalWrite(LEDPin,LOW);

}

if(buttonRead==0){

digitalWrite(LEDPin, HIGH);

}

Arduino, Arduino 9-Axis IMU Totorials, Tutorial

9-Axis IMU LESSON 4: Plotting Serial Data from Arduino with Control of Axis Scale

September 5, 2019 admin

As this project continues it is very important for us to be able to quickly and easily plot data streaming from the sensor. The Arduino Serial Plotter has some real limitations, we recommend a simple “Serial Plotter” tool that can be downloaded. In this video we take you step by step through the download and installation process, and then an overview of how to use the tool.

Technology Tutorials

Category Archives: Arduino

9-Axis IMU LESSON 6: Determine Tilt From 3-axis Accelerometer

Arduino Tutorial 28: Using a Pushbutton as a Toggle Switch

9-Axis IMU LESSON 5: Calibrating the BNO055 9-axis Inertial Measurement Sensor

Arduino Tutorial 27: Understanding Pushbuttons and Pull Up and Pull Down Resistors

9-Axis IMU LESSON 4: Plotting Serial Data from Arduino with Control of Axis Scale

Making The World a Better Place One High Tech Project at a Time. Enjoy!