Control the LEDs

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The aim of this example is to show how to control NAO’s LEDs using a proxy to ALLeds module. This example will make a colored animation on all of NAO’s LEDs.

The whole example is available here:

Source file:


* Copyright (c) 2011 Aldebaran Robotics. All Rights Reserved
* \file ledsexample.cpp
* \brief Play with NAO's leds.
* A simple example showing how to use NAO's leds using ALLedsProxy.
* This example launches a colorful animation on NAO's leds.
* We use here a specialized proxy to the ALLeds module.

#include <iostream>
#include <alerror/alerror.h>
#include <alproxies/alledsproxy.h>

int main(int argc, char* argv[]) {

  if(argc != 2)
    std::cerr << "Wrong number of arguments!" << std::endl;
    std::cerr << "Usage: movehead NAO_IP" << std::endl;

  try {
    /** Create a ALLedsProxy to call the methods to deal with NAO's leds.
    * Arguments for the constructor are:
    * - IP adress of the robot
    * - port on which NAOqi is listening, by default 9559
    AL::ALLedsProxy leds(argv[1], 9559);

    /** Set the duration of the animation. */
    float duration = 3.0f;
    /** Play a green / yellow / red animation on all of NAO's leds. */
  catch (const AL::ALError& e) {
    std::cerr << "Caught exception: " << e.what() << std::endl;



The corresponding CMakeLists.txt file is the following:


# Copyright (c) 2011 Aldebaran Robotics. All Rights Reserved.

cmake_minimum_required(VERSION 2.6.4 FATAL_ERROR)
# Give a name to the project.
# This include enable you to use qibuild CMake framework

# Create an executable named ledsexample,
# with the source file : ledsexample.cpp
qi_create_bin(ledsexample ledsexample.cpp)

# Tell CMake that movehead depends on ALCOMMON and ALPROXIES.
# This will set the libraries to link movehead with,
# the include paths, and so on
qi_use_lib(ledsexample ALCOMMON ALPROXIES)