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Want to get a humanoid robot up and running quickly? Here’s how: Download open-source software to handle the major robotic tasks.
The open-source robot movement has gathered steam in recent years with whole robot designs, software, and part lists now available on Web sites such as orocos. org and ros.org. Among the latest robot designs to use software available via open-source is one called REEM. Designed as a service robot, it stands 5.5-ft high so it can interact with humans at eye level. It has a mobile base that lets it move at 2 mph and a lithium battery that lasts up to 8 hr.
REEM has a motorized head and computer vision able to recognize and track faces. The commercially available robot also contains a microphone, stereo camera, laser and ultrasound sensors, accelerometers, and gyroscopes. It uses the equipment to identify its current position, move around autonomously, and avoid sudden obstacles or people walking across its path. A touchscreen in its chest lets the public connect with the robot. In a recent demonstration, REEM wandered around a trade show and provided directions to visitors.
REEM comes from a robotics R&D firm called PAL Robotics based in Barcelona, linked to the PAL Group of the United Arab Emirates. It is the culmination of work that started with a prototype called REEM-A, which was able to walk and play chess, and REEM-B, a more-advanced version.
Developers at PAL Robotics say they wanted to keep the robot relatively light, but with a low center of gravity and space to house the batteries. REEM weighs around 200 lb and can also carry up to 66‚lb on its lower loading platform. Each arm can move up to 6.5 lb independently. Two electronically commutated dc-motor microdrives from Dr. Fritz Faulhaber GmbH & Co. KG are in the robot’s neck and waist and let the bot exhibit some humanlike expressiveness. Thanks to their compact dimensions, the drives readily fit in these two “constricted” areas.
The small actuators move the head and torso independently of one another, letting the robot assume different postures and imitate human traits using body language that fits the occasion.
Fortunately for robotic enthusiasts, PAL Robotics makes a virtual model of the REEM robot publicly available that is compatible with the Robot Operating System (ROS). ROS is a software framework for developing robot software and it functions a bit like an operating system. Originally developed for an artificial intelligence project at Stanford University, ROS development continues primarily at Willow Garage, a personal robotics research institute in Menlo Park, Calif. ROS is open-source software and is free for commercial and research use.
ROS provides standard operating-system services such as hardware abstraction, low-level device control, message-passing between processes, and similar functions. Packages contributed by users (organized into sets called stacks) ROS provides standard operating-system services such as hardware abstraction, low-level device conimplement other functions, such as simultaneous mapping, planning, perception, and so on.
The model of REEM that PAL Robotics makes available includes kinematic, visualization, collision and (rough) dynamic descriptions. It also provides configuration files for loading the model into an opensource 3D robotic simulator called Gazebo, which Willow Garage supports.