Introduction: Motion Tracking Using MPU-6000 and Particle Photon
MPU-6000 is a 6-Axis Motion Tracking Sensor which has 3-Axis accelerometer and 3-Axis gyroscope embedded in it. This sensor is capable of efficient tracking of exact position and location of an object in the 3-dimensional plane. It can be employed in the systems which require position analysis to the highest precision.
In this tutorial the interfacing of the MPU-6000 sensor module with particle photon has been illustrated. To read the values of acceleration and rotational angle, we have used particle with an I2c adapter.This I2C adapter makes the connection to the sensor module easy and more reliable.
Step 1: Hardware Required:
Step 2: Hardware Hookup:
The hardware hookup section basically explains the wiring connections required between the sensor and the particle photon. Ensuring correct connections is the basic necessity while working on any system for the desired output. So, the requisite connections are as follows:
The MPU-6000 will work over I2C . Here is the example wiring diagram, demonstrating how to wire up each interface of the sensor.
Out-of-the-box, the board is configured for an I2C interface, as such we recommend using this hookup if you’re otherwise agnostic. All you need is four wires!
Only four connections are required Vcc, Gnd, SCL and SDA pins and these are connected with the help of I2C cable.
These connections are demonstrated in the pictures above.
Step 3: Code for Motion Tracking:
Lets start with the particle code now.
While using the sensor module with the arduino, we include application.h and spark_wiring_i2c.h library. "application.h" and spark_wiring_i2c.h library contains the functions which facilitate the i2c communication between the sensor and the particle.
The entire particle code is given below for the convenience of the user:
#include<application.h>
#include<spark_wiring_i2c.h> // MPU-6000 I2C address is 0x68(104) #define Addr 0x68 int xGyro = 0, yGyro = 0, zGyro = 0, xAccl = 0, yAccl = 0, zAccl = 0; void setup() { // Set variable Particle.variable("i2cdevice", "MPU-6000"); Particle.variable("xAccl", xAccl); Particle.variable("yAccl", yAccl); Particle.variable("zAccl", zAccl); Particle.variable("xGyro", xGyro); Particle.variable("yGyro", yGyro); Particle.variable("zGyro", zGyro); // Initialise I2C communication as Master Wire.begin(); // Initialise serial communication, set baud rate = 9600 Serial.begin(9600); // Start I2C transmission Wire.beginTransmission(Addr); // Select gyroscope configuration register Wire.write(0x1B); // Full scale range = 2000 dps Wire.write(0x18); // Stop I2C transmission Wire.endTransmission(); // Start I2C transmission Wire.beginTransmission(Addr); // Select accelerometer configuration register Wire.write(0x1C); // Full scale range = +/-16g Wire.write(0x18); // Stop I2C transmission Wire.endTransmission(); // Start I2C transmission Wire.beginTransmission(Addr); // Select power management register Wire.write(0x6B); // PLL with xGyro reference Wire.write(0x01); // Stop I2C transmission Wire.endTransmission(); delay(300); } void loop() { unsigned int data[6]; // Start I2C transmission Wire.beginTransmission(Addr); // Select data register Wire.write(0x3B); // Stop I2C transmission Wire.endTransmission(); // Request 6 bytes of data Wire.requestFrom(Addr, 6); // Read 6 byte of data if (Wire.available() == 6) { data[0] = Wire.read(); data[1] = Wire.read(); data[2] = Wire.read(); data[3] = Wire.read(); data[4] = Wire.read(); data[5] = Wire.read(); } delay(800); // Convert the data xAccl = ((data[1] * 256) + data[0]); if (xAccl > 32767) { xAccl -= 65536; } yAccl = ((data[3] * 256) + data[2]); if (yAccl > 32767) { yAccl -= 65536; } zAccl = ((data[5] * 256) + data[4]); if (zAccl > 32767) { zAccl -= 65536; } delay(800); // Start I2C transmission Wire.beginTransmission(Addr); // Select data register Wire.write(0x43); // Stop I2C transmission Wire.endTransmission(); // Request 6 bytes of data Wire.requestFrom(Addr, 6); // Read 6 byte of data if (Wire.available() == 6) { data[0] = Wire.read(); data[1] = Wire.read(); data[2] = Wire.read(); data[3] = Wire.read(); data[4] = Wire.read(); data[5] = Wire.read(); } // Convert the data xGyro = ((data[1] * 256) + data[0]); if (xGyro > 32767) { xGyro -= 65536; } yGyro = ((data[3] * 256) + data[2]); if (yGyro > 32767) { yGyro -= 65536; } zGyro = ((data[5] * 256) + data[4]); if (zGyro > 32767) { zGyro -= 65536; } // Output data to dashboard Particle.publish("Acceleration in X-Axis : ", String(xAccl)); delay(1000); Particle.publish("Acceleration in Y-Axis : ", String(yAccl)); delay(1000); Particle.publish("Acceleration in Z-Axis : ", String(zAccl)); delay(1000); Particle.publish("X-Axis of Rotation : ", String(xGyro)); delay(1000); Particle.publish("Y-Axis of Rotation : ", String(yGyro)); delay(1000); Particle.publish("Z-Axis of Rotation : ", String(zGyro)); delay(1000); }
Particle.variable() function creates the variables to store the output of the sensor and Particle.publish() function displays the output on the dashboard of the site.
The sensor output is shown in the picture above for your reference.
Step 4: Applications:
MPU-6000 is a motion tracking sensor, which finds its application in the motion interface of smartphones and tablets. In smartphones these sensors can be employed in the applications such as gesture commands for applications and phone control, enhanced gaming, augmented reality, panoramic photo capture and viewing, and pedestrian and vehicle navigation. MotionTracking technology can convert handsets and tablets into powerful 3D intelligent devices that can be used in applications ranging from health and fitness monitoring to location-based services.
