Latest news with #UniversityofRostock
Yahoo
3 days ago
- General
- Yahoo
Seals playing a video game reveal how they find their way
The world's harbor seals (Phoca vitulina) are masters in seeing through the cloudy coastal waters they call home. Equipped with dexterous whiskers, these pinnipeds use a suite of senses to navigate their surroundings with ease. Harbor seals may also use an important part of their vision to determine which direction they are moving, even with such an opaque view of the world. Now, we might know a bit more about how they can tell which direction they are heading. New research involving a simulated swim finds that the particles in cloudy water moving across the retina at the back of the seal's eye can tell them which way they are moving. The findings are detailed in a study published May 29 in the Journal of Experimental Biology. Harbor seals are commonly found along the eastern and western coasts of the United States. Adult harbor seals are about five to six feet long and they 'haul out' (aka rest) on various rocks, reefs, beaches, and glacial ice when not at sea. This coastal lifestyle means they must navigate in some very busy and murky waters in order to survive. [ Related: Arctic seals have special noses. ] 'We wanted to know whether harbour seals can determine their heading from optic flow fields – the pattern of motion on the retina generated as a seal moves past visible objects, including particles in the water, in their surroundings,' Frederike Hanke, a study co-author and neuroethologist at the University of Rostock in Germany, said in a statement. To examine this, Hanke and the team essentially set up an arcade for seals with a gaming challenge. They designed three different computer simulations to show three captive seals. One simulated moving through the open sea, with dots streaming towards the viewer out of the screen. The second used a plane of dots rushing towards the viewer to simulate the seabed passing below. The third emulated the surface of the sea flowing above the viewer's head using another plane of dots. The team then trained three seals–Nick, Luca, and Miro–to shuffle into place in front of a large screen and showed them the simulations. They were encouraged to indicate which side they were moving towards while watching the simulations (left or right) by touching a red ball with either side of their heats. In return, they were given sprats as a reward. According to Hanke, Nick and Luca were gaming veterans and picked up this new task with ease. Miro was a novice, but he was reportedly a very open-minded seal, and 'coped with all new situations easily.' Once the seals were comfortable with the game, the team kept track of the animals' choices as they watched the dots in the simulations. The simulations appeared to show that the seal was heading in a direction that was 22, 18, 14, 10, 6 or 2 degrees to the left, or in similar positions to the right. The team then plotted the animals' successes and mistakes, as the seals indicated which direction they believed they were travelling in during the simulations. 'These are living animals, not robots,' said Hanke. 'Errors are most likely due to inattentiveness or sometimes a drop in motivation.' When the team plotted the seals' successes, it was clear the animals were capable of determining which direction they were travelling based on the dots streaming in their view, the way that particles would look while they were really swimming. Even in faint lights, the seals appear to be able to use their vision to take advantage of cloudy water to determine which direction they are travelling based on the motion of objects and particles in the water going past their eyes. In future research, the team is hoping to find out whether they use this same visual effect to determine how far they have travelled.
BBC News
14-02-2025
- Science
- BBC News
Radio vision: See through smoke and around corners
If you want to find out whether your robot can see through smoke, well, you're going to need some a University of Pennsylvania student got a shock when they began setting up a late night experiment to test such a after flicking the switch on the smoke machine, a loud fire alarm went off. "The whole building got triggered," says Mingmin Zhao of the University of Pennsylvania, smiling. "My student called me. He was very surprised."The incident was a minor setback for the team developing a robot equipped with a innovative radio-based sensing waves could allow robots or autonomous vehicles to see through thick smoke, intense rain – or even around corners. Such waves can even detect concealed simulating visual imagery based on radio waves is an unusual approach for robots and autonomous vehicles. Much more established in those fields are regular optical cameras, light detection and ranging (Lidar), and other Prof Zhao and his students have developed a potentially powerful way for robots to see using radio course radar, which uses radio waves, has been used for decades to track aircraft, ships and the weather. But the spinning array on Prof Zhao's robot throws radio waves in all directions. An on-board artificial intelligence (AI) system then builds a 3D view of the environment with this information."What we have been trying to do here is basically help robots obtain superhuman vision – to see in scenarios where human eyes or traditional visual sensors cannot," explains Prof suggests the technology could help a future search-and-rescue robot save people from a burning tests of the bot used a clear plastic box full of smoke placed around the its spinning equipment, in order to avoid triggering any nearby fire alarms. Although humans can't see them, radio waves are a form of light in the sense that they are part of the electromagnetic spectrum, which also includes X-rays and gamma rays. Only a small part the spectrum is classed as visible light, radio waves can reflect off surfaces and materials, though in a slightly different way to visible light. Prof Zhao and his colleagues have designed their robot so that it can sense these radio wave crucial factor here is that radio waves are much longer than visible light waves meaning they are not blocked by tiny smoke Zhao says he has also been working on adapting the technology so that the robot can see part of the way round a corner. Think of it like a hall of mirrors, he suggests, just for radio waves rather than visible light."It's really very interesting work and quite impressive," says Friedemann Reinhard at the University of Rostock in Germany, who was not involved in the work. In 2017, Prof Reinhard and colleagues described how Wi-Fi signals could allow spies to see into private slight limitation is that the spinning array cannot, by definition, see in all directions at once. Prof Reinhard says that a lot of data processing carried out by the system appears necessary to clean up the image that results from this spinning the robot sends out radio waves in the millimetre wave band (waves that are between one and ten millimetres long). This is the same technology used for some 5G installations."That's potentially very attractive, it's a very well understood, cheap technology," says Prof Reinhard. "I certainly would love to see a self-driving car driving only on radar." But it is possible to avoid using spinning radio-emitting devices to get a full picture, says Fabio da Silva, founder and chief executive of US firm Wavsens, which is also developing radio-based sensing technology."We created an algorithm that allows you to sense the entire space instantaneously and continuously so we don't have to spin our antennas," he describes the system as akin to echolocation, used by bats. It sends out radio waves and "listens" to how the waves come back, which reveals the shape of whatever they have researchers have used radio waves to detect concealed weapons such as hidden handguns and waves can even "fingerprint" the details of a room. Then, if scanned again later, this would reveal whether any objects in the room have been year, scientists in Germany proposed that countries use this method to scrutinise other countries' management of their nuclear weapons stockpiles. It would be one way of knowing whether someone had been moving the warheads around, for example. Separately, Luana Olivieri at Loughborough University has explored using a different form of non-visible electromagnetic radiation, terahertz waves. These are shorter than radio waves but longer than visible light waves. "This wavelength is particularly unexplored," says Dr is possible to see through objects and analyse materials using this form of radiation, she adds. Such a system could even, in theory, identify specific drugs by detecting their chemical while seeing through materials could help a rescue bot find a trapped person in some future disaster, it also has other applications. Police forces and militaries have access to radio-based technology that allows them to see through doors and walls, to some extent."Warfighting is definitely one market that it caters to. It can be used to find and kill someone," says Mr da Silva. He has exhibited Wavsens' technology to the US Department of Defense and the Israeli Ministry of Defense, he yet these applications are not entirely surprising, suggests Prof Reinhard, who points out that a range of emerging technologies have, in principle, made it easier to detect and attack people."Maybe radar sounds scary – but drones and cheap cameras are the much more dangerous thing," he says.
