[Casual hacking] GPIO app PROJECT 1 : Traffic lights

[Casual hacking] GPIO app PROJECT 1 : Traffic lights

What is GPIO app PROJECT?

GPIO app PROJECT is automation projects created with GPIO ports of Raspberry Pi and apps for PROTA. The result is simple. Programming is building a logical formulation that executes specific operation using computer language. The combination of the two elements, GPIO and PROTA apps, give users a chance to build for themselves logical, working products, that we believe is an user-defined programming, that they can experience in just a couple of steps.

(Users can simply program in a couple of steps using GPIO by choosing sensors on the top and actuators on the bottom.)

Projects may vary depends on the combination of the apps. To start off, you’ll be able to grasp the basic idea of the GPIO app by following the instructions below.

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PROJECT 1 : Traffic lights

Have a look at the above two rules. By simply selecting and defining conditions that users desire, a formulation of traffic lights can be built in just three steps.

If you still have a hard time grasping the idea of Ambiency, please check out the link below.

[Quick & Dirty guide] Automation solution, Ambiency tutorial. Why not make your own rule?

[Quick & Dirty guide] Make an image file of Ambiency rule!

1. How to setup pins on the breadboard, LED, and webcam

Wire LED to GPIO pins 17 and 27.

2. Set up the GPIO app

Set the values of the above pins on the UI.

The saved values on this app becomes the source values when creating automation rules on Ambiency. Please click Remember & Save button to save.

3. Create automation rules!

Create two rules like the following by choosing the source values you've created in the above steps on the GPIO app.

• 1st Rule

• Sensor app - Webcam app
  Trigger - "Motion detected : Edge rising"
• Actuator app - GPIO app
  Action - "Write value : GPIO $pin : Write=1" & "Write value : GPIO %pin : Write=0"
• If motion detected is interrupted on Webcam -> write value 1 in the output of $pin on GPIO(app) to turn on a LED -> write value 0 in the output of %pin to turn off a LED.
• As a result, the rule turns on the green and turns off the red traffic lights on motion detection for pedestrian signals.

• 2nd Rule

• Sensor app - Webcam app
  Trigger - "No motion : Edge falling"
• Actuator app - GPIO app
  Action - "Write value : on GPIO $pin : Write=0" & "Write value : on GPIO %pin : Write=1"
• If No motion on Webcam -> write value 0 in the output of $pin on GPIO to turn off a LED -> write value 1 in the output of %pin on GPIO to turn on a LED.
• As a result, the rule turns off the green and turns on the red traffic lights on no motion for pedestrian signals.

4. Test and find out in History!

In this session, you’ve just created a working traffic lights by creating rules with GPIO. As shown in the first picture, there’re many combinations of rules that can be created with GPIO and other apps.

Please check out other projects you can try out in the coming sessions.

Thank you.