Robot Dog Master’s Land and Water Sports Like Real Mammals

Scientists unveil a groundbreaking amphibious robot that moves with excellent efficiency across multiple environments, with the potential to change how we handle search and rescue operations, environmental research and military applications.

Unlike previous amphibious robots that are primarily based on reptiles or insects, this new amphibious robot dog (ARD) draws inspiration from mammal swimming mechanics to achieve excellent mobility on land and underwater. Breakthrough Design details the long-term challenges of robot mobility in a study published on May 8 in IOP Publishing’s journal Biosmog and Bionics, and demonstrates how creating bionic types of quadruped mammals can create more multifunctional machines that can navigate our complex world.

The research team’s approach is very different from traditional amphibious robot designs, which often carry limitations in speed, agility, and transitions between environments.

Revolutionary design inspired by dog ​​swimming

The innovative robot directly observes its swimming function by observing the real dog paddling in the water. Unlike the amphibious robots that used to be excellent in one environment but shaky in another, this quadruped’s design maintains impressive performance on different terrains.

The key to the robot’s aquatic ability is a unique paddling mechanism that carefully replicates the dog’s swimming movement. The researchers designed the robot with a specially designed double-leg structure designed to optimize underwater propulsion while maintaining the ability to walk effectively on land.

“This innovation marks a big step forward in designing robots in a natural style,” explained Yungui, author of the study. “Our robot dog’s ability to effectively pass through water and on land is due to its biologically inspired trajectory planning, which mimics the natural paddling gait of a real dog. The double-leg structure and three different paddling gaits resolve previous limitations such as slow swimming speeds and impractical gait planning, which makes the robot dog more efficient in the water.”

Three unique swimming gaits are used for different priorities

A particularly interesting aspect of the study is the development of multiple paddling gaits, each with different advantages. Through extensive experimental testing, the team identified three different swimming modes:

• Two transverse sequence paddle gaits (LSPGs) have 25% and 33% power stages optimized for maximum speed and forward advancement
• Trotter-like paddle gait (TLPG) with 50% power stage, designed to prioritize stability over speed
• Each gait has systematically evaluated theoretical performance and real-world effectiveness
• Dog paddle-inspired gaits achieve higher speeds, while trotting-like methods provide enhanced stability

These specialized gaits allow robot dogs to achieve maximum water speeds of 0.576 km per hour (0.16 meters per second) while maintaining their speeds of 1.26 km per hour (0.35 meters per second) on land.

Precision engineering for environmental adaptation

Creating a well-performing robot in a variety of environments requires careful attention to weight distribution and buoyancy. The researchers carefully balanced the center of gravity and buoyancy to ensure stable movement in the water while maintaining land mobility.

This delicate balance represents one of the most challenging aspects of amphibious robot design. Too much attention to waterproofing and buoyancy can damage the robot’s land speed and agility, while optimizing land movements often make water navigation inefficient or impossible.

The waterproof robot dog design overcomes these challenges through its bionic approach, achieving what the researchers call “effective paddling gait in water with trotting ability on water.”

The science behind swimming robots

Before building the physical robot, the team conducted extensive theoretical modeling and experimental measurements of hydraulic power. They analyzed how different leg movements were performed underwater and then verified these predictions by actual testing.

The research process combines the biomechanical observation of real dog swimming with refined engineering principles. This methodical approach ensures that the robot’s movement is both natural and effective.

Static water experiments measure the fluid dynamics generated by each gait mode and then perform dynamic swimming tests to evaluate real-world performance. The results confirm that lateral sequence gait provides excellent propulsion and speed, while trotting-like paddling gait provides enhanced stability, as predicted by the team’s theoretical model.

Future applications across multiple fields

What makes this development particularly important is its potential for real-world applications. The ability to seamlessly navigate across a variety of terrains can revolutionize how we respond to environmental monitoring, disaster response and exploration of complex environments.

Can such robots ultimately help with flood rescue operations, conduct scientific research in coastal environments or assist with military reconnaissance of various terrains? The researchers believe that their work provides theoretical and practical guidance for the development of more capable amphibious robots inspired by mammalian mobility patterns.

With the continuous development of robotic systems, this study demonstrates the ongoing value of finding solutions to natural solutions to engineering challenges. By carefully observing and adapting to the mammal’s evolutionary movement patterns that have been evolving for over millions of years, engineers can create machines with unprecedented versatility, allowing the gap between land and water to be between lakes that dogs jump into.