Swimming pool game 'Marco Polo' inspiring robot detection

Washington, March 19 (ANI): A popular swimming pool game called 'Marco Polo' is guiding scientists as to how to make robots that can independently detect and capture other moving targets.

Engineers from Duke University and the University of New Mexico say that the simple pursuit-evasion game is providing them with useful information, which can be used to create such a system that will not only allow robots to "sense" a moving target but intercept it also.The researchers say that such systems have broad applications, ranging from security systems to track unwanted intruders like enemy ships or burglars, to systems that create radiation or environmental hazard maps, or even track endangered species.

'Marco Polo' players include a pursuer who has to tag another person, who then becomes the new pursuer.

The pursuers, who must keep their eyes closed, can call out 'Marco' at any time, and everyone else must respond by saying 'Polo'. This is how the pursuers can gradually estimate where the targets are in the pool, and where they might go.

"Games give us a good way of making these highly complex problems easier to visualize," said Silvia Ferrari, assistant professor of mechanical engineering and materials science at Duke's Pratt School of Engineering.

Rafael Fierro, associate professor of electrical engineering at the University of New Mexico, added: "Just as in 'Marco Polo', we needed to create a way that permits mobile robots to detect other moving objects and make predictions about where the targets might go. When done efficiently, the mobile sensor switches from pursuit mode to capture mode in the shortest amount of time."

Ferrari has already developed a similar type of algorithm, known as cell decomposition. The researcher has revealed that past experiments with the algorithm allowed a robot to move through space without colliding with stationary obstacles.

The latest experiments included not only robots equipped with camera sensors, but also stationary camera sensors that allowed for "coverage" of all the cells within the space.

"The idea is that multiple sensors are deployed in the space to cooperatively detect moving targets within that space. As the sensor makes more detections, it is better able to predict the likely path of the intruder. The ultimate path taken by the robot sensor is one that maximizes the probability of detection and minimizes the distance needed to capture the target," Fierro said.

The resarcher say that apart from security and military applications, the new algorithms may also be be used in other ways to detect targets that are not necessarily intruders.

"Targets could be completely different things, like mines or explosives, or chemical or radiation leaks. The robots can use their sensors to keep track of the detected locations and build a 'map' to let people know where to go or not to go," Fierro said.

The algorithms could also be used to help explain natural phenomena, such as the behaviours of the members of a wolf pack as they chase and capture their prey.

The latest experiments, conducted at the University of New Mexico, involved intruders moving in straight lines at a constant speed.

"We are now developing algorithms that will more closely mimic the real world by giving intruders the ability to take evasive actions. The other main issue is to ensure that all the different mobile sensors can communicate with each other at all times and coordinate their activities based on that communication," Ferrari said.

An article on the research project has been published online in the Journal on Control and Optimization, a publication of the Society for Industrial and Applied Mathematics. (ANI)