Engineering: This year’s top engineering feats smack of the sort of sci-fi future-gazing you can find in retro issues of Popular Science. Ski on top of a trash incineration plant—in the middle of a city! Eat bacon made from mushrooms! Control a prosthetic arm with your mind! But our winners have more going for them than just the gee-whiz factor: each item on this list is helping to create a more just, sustainable world, whether by protecting the environment or by improving our health and safety. That’s a sci-fi future we can get behind.

LUCI smart wheelchair accessory by LUCI

A safer wheelchair

Motorized wheelchairs can weigh upwards of 300 pounds, and it only takes a 2.5-inch dropoff to tip one over. That’s in part why there are roughly 30,000 annual hospitalizations from wheelchair accidents in the US alone. LUCI aims to eliminate those with an attachment that retrofits certain power chairs with a combination of ultrasonic sensors, cameras, and radar. Combined, they provide collision avoidance and drop-off protection to keep riders safe—plus, they boast an anti-tip alert system that automatically notifies loved ones in case of an accident. Its $8,500 price tag is steep, especially without the help of insurance, but the folks at LUCI are hoping to secure coverage soon.

View the whole list