Bird in the hand: Robotics, vision systems aid search for rare woodpecker

By Control Engineering Staff February 20, 2007

Berkeley, CA —A high-resolution, intelligent robotic video system developed by researchers at three major universities is finding applicability for tasks beyond automation and control. The equipment, developed by researchers from the University of California, Berkeley, and Texas A&M University, hangs in the bayous of eastern Arkansas, amidst ancient trees and swamp creatures, patiently waiting to capture video of an elusive bird once thought to be extinct.

The high-resolution intelligent robotic video system, installed in the Bayou DeView area of the Cache River National Wildlife Refuge in Arkansas, is part of a major effort to locate the ivory-billed woodpecker in its historic habitat. The new robotic video system is also providing detailed video sequences of other birds, suggesting a new high-tech approach to doing field biology work. Ken Goldberg, a UC Berkeley professor of industrial engineering and operations research, and of electrical engineering and computer sciences, presented initial samples from the video system last weekend in a news briefing on the future of robotics held at the annual meeting of the American Association for the Advancement of Science (AAAS) in San Francisco.

The robotic video system is part of a new project, called Collaborative Observatories for Natural Environments (CONE) and funded by the National Science Foundation, to develop automated systems that can observe and record detailed natural behavior in remote settings. Goldberg and his former graduate student, Dezhen Song, now an assistant professor of computer science at Texas A&M, are co-principal investigators of the project.

The search for the ivory-billed woodpecker is being made throughout the Southeast by U.S. Fish & Wildlife and in the Cache River Refuges of Arkansas by the Arkansas Game and Fish Commission. The bird had been feared extinct until sightings in recent years revived hopes of its survival. However, most eyewitness observations are inconclusive.

Researchers are hoping to obtain a high-resolution video clip that would provide definitive proof of the bird’s existence. However, simply pointing video cameras at the sky and recording is not practical, as the images would quickly fill up a computer’s hard drive. The challenge, they say, is for the software to recognize when animals are present automatically. “Passive infrared (PIR) motion sensors are sometimes used in wildlife research,” said Goldberg. “The problem is that PIR sensors look for heat and are not triggered by birds flying overhead. So we’re developing a robotic system that analyzes high resolution video in real time.”

The system was placed in the Cache River National Wildlife Refuge near a power line that cuts through the bayou and provides a 50-ft-wide clearing unobstructed by trees. “At this location, said Ron Rohrbaugh, project director at the Cornell Lab of Ornithology, “we should have the highest probability of capturing an image of the ivory-billed woodpecker.”

With the help of the Arkansas Electric Cooperative, a 69 kV transformer was erected for the project that provides a power source and a post to mount the equipment. Two cameras, one pointing east and the other west, are connected to a computer that processes the data. Waterproof gear helps protect the equipment from the elements. The researchers created software that keeps video files only when potential “bird flight” movement is sensed. It is based on algorithms that can handle the unpredictable conditions of a natural environment, filtering out false readings from clouds, water reflections and falling leaves. The program, said Song, knows that the bird, for example, flies 20 to 40 mph and deletes anything outside that range. “The high-resolution camera we have shoots at 22 frames per second,” he added, “with approximately 2 to 3 megapixels per frame. That’s a huge amount of data that must be managed.”

An autonomous camera is more alert than a human bird watcher and less disturbing to the environment. The camera also enables the search season to extend throughout the year. The researchers are continuing to fine tune the system and algorithms while combing carefully through each new set of video that is collected. Said Rohrbaugh, “Certainly going into this I had a lot of skepticism about the usefulness of this robotic camera. But now there’s hope that by using this camera, we can get a hi-res image that is an indisputable piece of evidence that the ivory-billed woodpecker is living in Arkansas.”