Cog - Humanoid Robot

Overview:
Cog is a humanoid robot developed by the Artificial Intelligence Laboratory at MIT. The robot is used as a platform on which to bring together and explore the many subfields of human and artificial intelligence. The robot consists of a trunk, a head, and two arms and hands. It has no legs nor a flexible spine. It is equipped with sensory systems to mimic those of humans, including sight, hearing, touch, proprioception and a vestibular system. A voice is currently being worked on.

The philosophy adopted by this research group is that the form of our bodies is an essential ingredient for the development of internal thought and language. Therefore human-like artificial intelligence can only be created in a robot with human-like form. Also, human-like intelligence develops through the interaction with other humans. Thus it must be easy and natural for humans to interact with the robot.

The Brain:
Cog does not have a single central all controlling "brain". Instead Cog is controlled by a heterogeneous network of many different processors. The individual joints are each controlled by small dedicated microcontrollers, such as the Motorola 6811. These microcontrollers process inputs such as feedback from strain gauges, perform servo calculations, and drive the motor responses. Audio and visual pre-processing is performed by digital signal processor (DSP) networks consisting of Texas Instruments C40's. The core controlling network consists of 200MHz industrial PC's running the QNX real-time operating system and connected by a 100VG Ethernet. The core network currently consists of 4 nodes, but this number can be easily increased by simply plugging new nodes into the network. The DSP's relay data to the core processor network via ISA and PCI interface cards.

Sensory Systems:
Cog's visual system mimics that of humans in that it is binocular and each eye can rotate about a vertical and horizontal axis. Each eye is made up of two greyscale cameras, one for the wide-angle view of the peripheral visual field, and one for the narrow-angle view of the centre of the visual field.

Hearing is enabled by a pair of microphones similar to those used in hearing aids. Stereo sampling of sound occurs at 22.05kHz with an 8 bit resolution. The purpose of Cog's auditory system is to provide real-world, robust hearing similar to that of humans. The auditory system is heavily integrated with other modalities such as vision, motor, etc. Sound localization has been achieved and current research is focussed on the segregation of multiple sound streams.

Cog's vestibular system also mimics that of humans. The 3 semi-circular canals found in humans are implemented as 3 rate gyroscopes positioned on orthogonal axes. Cog also has 2 linear accelerometers. All of these are mounted in the head just below eye level.

A rudimentary tactile system has also been implemented. A 6x4 array of sensors on the front of the robots torso can detect the position and force of a touch. Similar systems have been used on some of the hands built for the robot.

Links:
The Cog Shop: www.ai.mit.edu/projects/humanoid-robotics-group/cog
Kismet: www.ai.mit.edu/projects/humanoid-robotics-group/kismet