The field of robotics has taken a significant leap forward with the development of an amphibious robotic dog, capable of efficiently navigating both land and water. This innovative creation was inspired by the remarkable mobility of mammals in aquatic environments.

Unlike existing amphibious robots that often draw inspiration from reptiles or insects, this robotic canine is based on the swimming style of dogs. This design choice has allowed it to overcome several limitations faced by insect-inspired designs, such as reduced agility and load capacity.

The key to the amphibious robot’s water mobility lies in its unique paddling mechanism, modeled after the natural swimming motion of dogs. By carefully balancing weight and buoyancy, the engineers have ensured stable and effective aquatic performance.

To test its capabilities, the researchers developed and experimented with three distinct paddling gaits:

* A doggy paddle method that prioritizes speed
* A trot-like style that focuses on stability
* A third gait that combines elements of both

Through extensive experimentation, it was found that the doggy paddle method proved superior for speed, achieving a maximum water speed of 0.576 kilometers per hour (kph). On land, the amphibious robotic dog reaches speeds of 1.26 kph, offering versatile mobility in amphibious environments.

“This innovation marks a big step forward in designing nature-inspired robots,” says Yunquan Li, corresponding author of the study. “Our robot dog’s ability to efficiently move through water and on land is due to its bioinspired trajectory planning, which mimics the natural paddling gait of real dogs.”

The implications of this technology are vast and exciting, with potential applications in environmental research, military vehicles, rescue missions, and more. As we continue to push the boundaries of what’s possible with robotics, it’s clear that the future holds much promise for innovation and discovery.

A breakthrough in augmented-reality (AR) technology has been made by POSTECH researchers, which could revolutionize the way we interact with everyday life. The core AR device, typically bulky and heavy, can now be designed to be thin and light, making prolonged wear comfortable.

One of the main hurdles to commercializing AR glasses was the waveguide, a crucial component that guides virtual images directly to the user’s eye. Conventional designs required separate layers for red, green, and blue light, leading to increased weight and thickness. POSTECH researchers have eliminated this need by developing an achromatic metagrating that handles all colors in a single glass layer.

The key to this innovation lies in an array of nanoscale silicon-nitride pillars whose geometry was finely tuned using a stochastic topology-optimization algorithm to steer light with maximum efficiency. In experiments, the researchers produced vivid full-color images using a 500-µm-thick single-layer waveguide – about one-hundredth the diameter of a human hair.

The new design erases color blur while outperforming multilayer optics in brightness and color uniformity. This breakthrough has significant implications for the commercialization of AR glasses, which could become as thin and light as ordinary eyewear. The era of truly everyday AR is now within reach.

“This work marks a key milestone for next-generation AR displays,” said Prof. Junsuk Rho. “Coupled with scalable, large-area fabrication, it brings commercialization within reach.”

The study was carried out by POSTECH’s Departments of Mechanical, Chemical and Electrical Engineering and the Graduate School of Interdisciplinary Bioscience & Bioengineering, in collaboration with the Visual Team at Samsung Research. It was published online on April 30, 2025, in Nature Nanotechnology.

This research was supported by POSCO Holdings N.EX.T Impact, Samsung Research, the Ministry of Trade, Industry and Energy’s Alchemist Project, the Ministry of Science and ICT’s Global Convergence Research Support Program, and the Mid-Career Researcher Program.

The study, conducted by University of Bristol academics, has shed light on the importance of tailoring social media to suit individual needs. By categorizing users into distinct groups based on their motivations and behaviors, researchers have found that finding the right level of personal investment is key to a positive experience online.

The research revealed three main user types:

1. Those who browse without strong intentionality, often mindlessly scrolling through feeds.
2. Those deeply invested in their online lives, potentially leading to compulsive use and negative consequences for well-being.
3. Those who see value in using social media but retain personal distance, arguably having the best outcomes overall.

The findings suggest that social media platforms could be redesigned to support more intentional use by introducing customized features tailored to different user needs. This approach has the potential to help users regain control over their time online and make it more purposeful and valued.

By adapting interfaces to align with individual well-being, social media platforms can promote sustainable engagement connected to things that matter to the user, rather than just maximizing screen time. The implications of this work extend beyond social media design into technology use more broadly, offering a data-driven approach to promoting digital self-regulation and overall well-being.

The next phase of this research will explore how social media platforms can identify different user groups and adapt interfaces to support intentional online engagement that prioritizes personal well-being.