Robotics

Microrobot system regenerates knee cartilage in rabbits

A team of researchers affiliated with multiple institutions in China and one in Korea has developed a micro-robot system that regenerated knee cartilage in rabbits. In their paper published in the journal Science Advances, ...

Consumer & Gadgets

Samsung's home helper shaped like ball and rolled to CES

Samsung at CES showed its ball-shaped rolling robot that follows you around, beeps and performs tasks as your personal assistant. The company posted a video showing just how Ballie would help out in your home.

Engineering

A smart, self-powered ping-pong table

A team of researchers from China and the U.S. has built a smart, self-powered ping-pong table. In their paper published in the journal Nature Communications, the group describes how the table was built and how it powers itself.

Robotics

New robot hand is soft and strong

50 years ago, the first industrial robot arm called Unimate assembled a simple breakfast of toast, coffee, and champagne. While it might have looked like a seamless feat, every movement and placement was coded with careful ...

Computer Sciences

How a computer learns to dribble: Practice, practice, practice

Basketball players need lots of practice before they master the dribble, and it turns out that's true for computer-animated players as well. By using deep reinforcement learning, players in video basketball games can glean ...

Hi Tech & Innovation

A system for influencing hypnagogic micro-dreams

A team of researchers at MIT has created a hand-worn device that they claim can influence a person's micro-dreams during hypnagogia. The group has announced their device by posting a page describing it on an MIT website. ...

Energy & Green Tech

Using crumpled graphene balls to make better batteries

Lithium metal-based batteries have the potential to turn the battery industry upside down. With the theoretically ultra-high capacity of lithium metal used by itself, this new type of battery could power everything from personal ...

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Ball

A ball is a round, usually spherical but sometimes ovoid, object with various uses. It is used in ball games, where the play of the game follows the state of the ball as it is hit, kicked or thrown by players. Balls can also be used for simpler activities, such as catch, marbles and juggling. Balls made from hard-wearing materials are used in engineering applications to provide very low friction bearings, known as ball bearings. Black powder weapons use stone and metal balls as projectiles.

Although many types of balls are today made from rubber, this form was unknown outside the Americas until after the voyages of Columbus. The Spanish were the first Europeans to see bouncing rubber balls (albeit solid and not inflated) which were employed most notably in the Mesoamerican ballgame. Balls used in various sports in other parts of the world prior to Columbus were made from other materials such as animal bladders or skins, stuffed with various materials.

As balls are one of the most familiar spherical objects to humans, the word "ball" is used to refer to, or to describe, anything spherical or near-spherical.

This text uses material from Wikipedia, licensed under CC BY-SA