NAO Next Gen is a French robot designed in the labs of Aldebaran Robotics company based in Paris. NAO is an advanced humanoid robot with autonomous features and open platform for education and research. Since 2004 when the first generation was released, the robot has gone through many changes until 2011 when the last version was released and called NAO Next Gen.

For education and research, 2011 brought a very advanced tool with NAO Academics Edition designed for social applications, researches in computer science or human-robot interaction.

From the interaction of academic skills, NAO offers the possibility to develop and add new educational applications inspired by behavioral approaches.

For complete usage in education or research based on the idea to develop the next generation of home robots, the NAO was designed as a fully programmable platform while the company offers complete documentation in order to help everyone who wants to add new programming lines in the robot memory. Many sensors and actuators give users freedom to add new functionalities and build new applications for recognition or interaction.

The 58 cm (23-inch) tall and with 25 degrees of freedom, the robot structure offers great flexibility while inside has a powerful 1.6 GHz processor that runs the Linux operating system.

Inside, the robot has embedded software located in the head and running for autonomous behavior, while outside the user can run on computer desktop software for remote control or to create new applications for the robot.

Beside the based platform Linux, the robot uses an OpenNAO operating system for embedded systems or to develop applications.

Moreover, because an advanced robot is based on complex hardware and software systems, below I made descriptions of the main parts of the NAO together with its underlying software.

NAO has weaknesses and these are the battery, the ultrasonic sensors located in the chest, and a limited interaction in communication.
The battery has a working time between 60 to 90 minutes, a short time when the robot can be used until the next recharging cycle.

The second weakness of the robot is the ultrasonic sensors with a range that start from 25 centimeters. These sensors were attached to the body for object detection, but what happens if an object is located under the 25 centimeters where the ultrasonic sensors are not working?

Even the robot has support for up to eight different languages, it doesn’t have the capacity to maintain an interactive communication as long as the answers are almost entirely predefined.

NAO Head

NAO head is like a box that brings together sensors, vision systems and loudspeakers. Like humans, the NAO has vision and systems used for vision. The two eyes are two infrared sensors while on left and right sides are located two loudspeakers. Depending on the equipment version, at the top can be located up to four microphones integrated in different zones of the head for 360 degrees of sound capture. To capture clear sound waves from different directions, the head has a microphone located in front, two microphones located on the sides, and another microphone located at rear side. Having different location for all four microphones, the robot can detect the direction of the sound based on milliseconds time measure until the sound wave will hit all four microphones. If the sound is emitted from the right side, the right microphone will capture first these sound waves while the same sound waves will hit the other microphones after a few milliseconds.

With communication capabilities like voice recognition or speech, NAO is a multilingual robot with support for up to eight different languages.

In addition, the head hosting two video cameras located in the forehead and with 920p resolution. Both cameras are used by the visual system for objects or human identification.

Emotions are also present in the NAO project and are represented by LED’s located in the zone of eyes and ears. The robot has integrated at the top of the head three capacitive sensors to respond at the touch. Two electric motors offer flexibility for head and in the same time support the head.

NAO Body

The head, arms, and legs are linked and controlled by the body. Inside, the body of NAO hosting the battery, sensors, processing unit, and other communication systems. The motors and actuators offer the highest flexibility of the robot, and according to the specifications of electric motors, there are located three types of electric motors. From small to high torque, the body uses the electric motors to produce motion for head, arms, and legs.

The brain of the robot is not located in the head, is located in the body. A powerful 1.6GHz processor and 1GB of RAM memory hosting the parallel process that controls all robotic systems. For storage are available two flash memory cards, one card has a capacity of 2GB and is used exclusively for basic functionalities of the robot, while another card with 4/8GB can be used by the user.

With a fully programmable and opened platform, NAO can be programmed for new applications. Based on Linux, the robot can run any application developed in C++, Python, Java, MATLAB, Urbi, C, .Net programming languages.

The battery is located in the body of the robot and has an autonomy of 60 minutes if the robot is very active, or 90 minutes in normal use. The capacity of the battery is 27.6 Wh and can be charged in about 2 hours.

NAO can walk and dance, two tasks that cannot be possible without the inertial unit located in the torso. This unit designed to maintain the balance of the robot uses two gyrometers sensors and only one accelerometer sensor.

The chest hosting two ultrasonic sensors to measure the distance between the robot and objects from the environment. Each ultrasonic sensor is split into transmitter unit and receiver unit. The range of ultrasonic sensors is between 25 centimeters to 255 centimeters.

Three tactile sensors are located in the head, while on the chest of the robot is located only one tactile sensor.

Arms and Legs

Two arms and two legs are designed to mimic the human body. Each arm has five degrees of freedom while each hand has only one degree of freedom. Five degrees of freedom are available for each leg and offer the flexibility for walking or dancing.

Tactile sensors are available in each hand and are controlled in order to ensure safety both for humans and for the robot. On the feet are located force sensitive resistors that measure the resistance when a pressure is applied.

Applications

Using a mobile device like an iPhone, any user can build application to control the robot. From animation for games and interaction, the robot is an inexhaustible resource for entertainment and education.

Specifications

• Dimensions: (HxDxW) 573×275×311mm / 22.5×10.8×12.2 inch;
• Weight: 5.2kg / 11.4 lb;
• Autonomy: 60 minutes for active use, 90 minutes in normal use;
• Degrees of freedom: 25;
• Processor: Intel Atom at 1.6GHz;
• RAM memory: 1 GB;
• Built-in OS: Linux;
• Compatible OS: Windows, Mac OS, Linux;
• Programming languages: C++, Python, Java, MATLAB, Urbi, C, .Net;
• Vision: 2 x HD 1280×960 cameras;
• Connectivity: Ethernet, Wi-Fi;
• Microphones: 4;
• Loudspeakers: 2;