Step 1: 1 – User Interface

We want to use the spectrum analyzer shield to process the audio signal that’s generated from the RealSmartz App. First obtain a male to male AUX(audio) cable. Plug one end to the input jack of the shield and the other to the Apple device. For the newer Apple device you need to obtain an extension cable. Next, launch the RealSmartz App.

Step 2: 2 – Drive Train Interface

Attach the Spectrum Analyzer Shield to the Arduino Uno and pwm pin 3 to Servo and 5 to ESC of the RC car. First make sure the pins line up correctly between the Spectrum Analyzer Shield and Arduino Uno. Push down with slight pressure and the two parts should fuse into one unit. Next, connect the power of the servo to v3and ground of the Arduino.

Step 3: ✅ Putting Everything Together

Upload and modify the driveTrainArduino/driveTrainArduino.ino to the Arduino and test everything out.The Servo and ESC value is specific to your RC car and may not be the same.

Step 4: Materials

- RealSmartz running on Apple device [iPhone, iPad, iPod touch]:

- https://itunes.apple.com/us/app/real-smartz/id138...

- Spectrum Analyzer Shield:

- https://www.sparkfun.com/products/13116

- https://www.ebay.com/itm/Arduino-Uno-Compatible-Dual-MSGEQ7-Spectrum-Analyzer-Breakout-Board-Shield/322619787678

- Male to male AUX(2.5 Audio) cable

- Arduino Uno: https://store.arduino.cc/usa/arduino-uno-smd-rev3

- Arduino Uno drive train program

- https://github.com/DownloadTheBearCompany/BigTrakReborn/blob/master/driveTrainArduino/driveTrainArduino.ino

- RC Car, **convert the RC car to the point it's drivable with the Arduino**

- https://www.sparkfun.com/tutorials/348

- https://www.instructables.com/id/RC-Car-to-Robot/

- https://www.instructables.com/id/How-to-convert-almost-any-27-or-49-MHz-RC-Car-in/

- More: https://www.google.com/search?q=convert+rc+car+ar...

Step 5: Test It Out on the Field

Added a few GPS instructions on RealSmartz App. The RC car should be able to drive towards the GPS way points. If your RC Car is behaving incorrectly. Give your iPhone a call. It will stop the Car at its track.