On a small darkened platform a handful of fruit flies wander aimlessly. There is a brief flash of light and a robotic arm darts downward, precisely targeting a fly’s thorax, a moving target roughly the size of a pinhead. The fly seems unfazed, appearing not to notice that it has been snatched by a high-speed laboratory robot. The system, which has been prototyped by a team of biologists and roboticists at Stanford, makes it possible automate many aspects of research on Drosophila, one of the most popular experimental animals.
Tasks such as determining gender, measuring the size of body parts and even performing micro-brain surgery — long performed by graduate students armed with tweezers — can now be assigned to a robot. In one experiment, the robot exposed a fly running on a tiny trackball to different odors as the researchers recorded its changing path. The robot arm is extremely precise and uses the fly’s legs as shock absorbers, to avoid crushing or impaling the insects. The robot is also far more efficient than the previous grad student-powered methods.