Metin Sitti at the Max Planck Institute for Intelligent Systems in Stuttgart, Germany, and his colleagues have developed tiny robots called “microrollers” that can carry cancer drugs and selectively target human breast cancer cells. The team drew inspiration for the design of the robots from white blood cells in the human body, which can move along the walls of blood vessels (血管) against the direction of blood flow.

The microrollers are round and made from glass microparticles. One half of the robot was coated with a thin magnetic nanofilm (磁性纳米膜) made from nickel and gold. The other half was coated with the cancer drug doxorubicin as well as molecules that recognize cancer cells.

The team tested the robots using mouse blood and artificial channels lined with human endothelial cells—the kind of cells that line the inner walls of our blood vessels. The robots were exposed to a mixture of cancerous and healthy tissue. The microrollers selectively attached to the cancer cells and were activated using UV light to release the doxorubicin.

By applying magnetic fields, the team was able to control the movement of the microrollers, both with and against the flow of blood. The microrollers can reach a speed of up to 600 micrometers per second. “If you come to a spot where you need to take the right path and if you miss it, then you could go back and go to the right one,” says Setti.

In future, the researchers want to use other methods to start the drug release, such as heat or near-infrared light. They also plan to try making microrollers out of materials that would break down in the body over a few weeks or months.

The team hopes to test the microrollers in animals soon. “The rollers need to carry enough cancer drugs, which is why we need to have them in large numbers,” says Setti. “But since we can locally take drugs to the right target, we don’t need huge dosages (剂量).”

This could be the perfect gift for the partner, who embarrasses you on the dance floor. Smart socks, which can teach to dance, may be the answer for anyone with two left feet.

The socks have been developed as a running tool to help runners improve their skills. Thanks to the socks, users can accurately record not only how far and fast they run but also how well. It means the user maximizes their performance, and reduces damage to body and prevents hurt. The hi-tech socks are made of special fibers that watch the movements of your feet. They look, feel and can be washed like normal clothes.

Sensors (传感器) record each movement and send it by an ankle transmitter (脚踝发射器) to a smart phone. Then a “virtual coach” application shows the information and can tell the user what they are doing wrong, and help to improve skill in any task with feet.

The socks should be useful to athletes and weekend joggers. “People think running is so easy and of course everybody can do it but not necessarily safely and well,” Dr. Davide Vigano said. A recent study showed that between 60 and 80 percent of runners got hurt per year. This is pretty much more than any other human activity. Researchers say the technology can also be developed to teach people how to dance, play sports such as golf, or even to help to teach women to walk better in high heels.

Mr. Vigano said, “People could all benefit from the idea. We have had interest from all sorts of sports, like skiing, football, cycling and golf. Anything where you have to use your feet can use it. It could even be put in high heels to help women walk in them safely.”

Socks are just the start, and the technology could be used in gloves, hats and boots. The socks, anklet and software package, are expected to be sold for around￡120, which will go on sale in March.

Every year, TIME highlights inventions that are making the world better, smarter and even a bit more fun. Here are some select ones that will absolutely blow your kids’ mind.

Coding is a matter of problem-solving and pattern recognition. Sphero Indi teaches both, no screen required. Instead, kids use different-colored cards to move a robotic car from point A to B — green cards increasing its speed, pink cards telling it to turn left, and so on. “We really wanted to bring these abstract concepts into the physical world.” says Jef Wiencrot, one of the product developers.

For children who are upset for some reason, Purrble comes to their rescue. An interactive toy equipped with seven sensors that respond to touch. Purrble’s heartbeat speeds up when it senses somebody’s playing with it. Kids can then comfort their companion with gentle petting, slowing Purrble’s rapid heartbeat to a purr (咕噜声) — calming themselves as well in the process.

The effort to get kids interested in science has just got a helping hand — a cyborg hand, to be precise. Kids build a robotic arm that copies their hand gestures, while they learn about engineering and robotics. Once assembled (组装) and slipped on like a glove, the device passes forces from the user’s fingers to the extended ones of the robotic hand.

The Lego Group, intending to make all Lego bricks from sustainable sources by 2030, spent the past three years testing different recycled PET plastic materials, and finally developed its first recycled PET brick that is nearly identical to the usual brick. The Danish toy company hopes to integrate the recycled blocks into Lego sets in the next 18 to 24 months.