April 2001

Spherical Robot

By Technology Review

Today's robotic arms have limited flexibility, with many robots requiring up to six arms to achieve a complete range of motion. But now engineers at the Johns Hopkins University have laid the groundwork for robots with increased flexibility and accuracy by developing a spherical motor that can turn 360 degrees. Operating more like a shoulder joint than the elbow joints of current design, the prototype comprises 16 electromagnets arranged around a hollow sphere. When activated by a software-controlled electrical signal, the electromagnets attract 80 permanent magnets located inside the sphere, thereby causing motion. Within five years, the motor may be used in omnidirectional wheels, robotic cameras and even a smart computer mouse, directed by software agents. -V. Herrera