UnityBioFeedbackTesting

Getting data from Arduino into Unity Serial Ports

• Setting up the Arduino and Pulse Sensor with Bluetooth
• Reading values in Unity
• Particle Systems in Unity

Setting up the Arduino and Pulse Sensor with Bluetooth

Items necessary:

• Arduino Uno (any model is fine)
• USB B cable
• HC-05 Bluetooth Module
• Pulse Sensor

Step 1: Connect Arduino to Computer containing Arduino IDE and HRVSensor.ino using a USB B cable

Step 2: Connect the Pulse Sensor to the Arduino (black wire to Ground, red wire to 3.3V power, and purple wire to A0 - Analog Input 0)

Step 3: Verify and Upload the HRVSensor.ino sketch to the Arduino Uno (make sure to select the correct COM port under Tools

Step 4: Open Serial Monitor (or Serial Plotter) to view the heart rate readings

Step 5: Disconnect Arduino from the Computer

Step 6: Connect the Bluetooth Module to the Arduino

• RX on HC-05 connects to TX on Arduino
• TX on HC-05 connects to RX on Arduino
• GND (ground) on HC-05 connects to GND on Arduino
• VCC (power) on HC-05 connects to 5V on Arduino

Step 7: Connect the Arduino UNO to an external power source (either a portable power bank or a power outlet)

Step 8: Connect to Bluetooth from the computer

• Open Bluetooth Preferences and connect a device named "HC-05". The password is 1234.

Step 9: Select the COM port in Arduino IDE

• On a Windows, go to Bluetooth Settings (click on more options in Settings>Bluetooth)
• Click on the tab COM ports
• Use the COM port that is "Outgoing" and has the name "HC-05 'Dev B'"
• Select the above COM port (with the correct #!) in the Arduino IDE under Tools>Port

Step 10: Open Serial Monitor and see the values transmitted through Bluetooth!

Reading values in Unity

HRCollector.cs contains code to open and listen to the Serial Port 9600 (default + recommended for Bluetooth) in Unity.

• Create a new object in Unity.

• Click on the object, and in the Inspector tab, add a component called as New script. Title the script HRCollector. Add the code from HRCollector.cs.

• In the script, change the COM port to the one used earlier in the Arduino Sketch when reading via Bluetooth.

  line 16: SerialPort sp = new SerialPort("\\.\COM3", 9600);

  Windows format: \.\COM<#>

  Mac format: /dev/tty.HC-05-DevB

This script contains public static variables (essentially global variables) so that other scripts can access the values. Other scripts can access the variables by HRCollector.<variable_name>

For example,

In HRCollector.cs

public static int heartRate;

RandomAwesomeObject.cs accesses the variable through the class HRCollector

myfunc(HRCollector.heartRate);

Particle Systems in Unity

• Create a new object in Unity
• Click on the object, and under Inspector, add a component called as Particle System
• You can change the color, texture, size, etc of the particles under properties for the Particle System in the Inspector.
• In order to manipulate the parameters of the newly created Particle System through code, reference the awesome documentation here. RandomVariability.cs contains code that manipulates a particle system in Unity.