From Human to Humanoid.(Company Business and Marketing)

Physics-based simulations move robots toward more lifelike motion

The general perception of robotic movement as slow, choppy, and mechanical may soon fall by the wayside as researchers specializing in the digital re-creation of human motion are extending their innovative technology to the robotic realm. Boston Dynamics Inc. (BDI), an R&D company based in Cambridge, Massachusetts, has partnered with Sony Corp. to develop a simulator for modeling the physics and control mechanisms for a prototype robot that Sony is developing for entertainment applications.

The technology, which utilizes real-time 3D graphics to display the simulated behavior, enables Sony engineers to test ideas for robot control and behavior in software, before trying them on the real robot.

The robot simulator is an outgrowth of BDI's human simulation tools. Building on the existing technology required adapting the basic model of human kinematics and geometry to the kinematics and geometry of the Sony robot, according to Marc Raibert, BDI president and former robotics professor at the Massachusetts Institute of Technology, where the BDI technology was born.

"We also had to model the specific electric motors and drive trains used by the robot, rather than what we use for human simulation, and we expanded the ground-contact simulation, so the robot can sit or lie on the ground and behave properly when it gets up."

Critical to the development of the technology has been the use of 3D visualization to analyze the simulation. "When developing a robot or robot-control system, progress can be accelerated by having a good visualization of what is going on" says Raibert. For example, he says, "we sometimes display the simulated forces calculated by the physics as 3D vectors to show where the forces are applied to the body. And it is very useful to vary time when viewing behavior--perhaps moving forward and backward in time to see what happened at a particular event--and coordinating the ...