Welcome to How Stuff Works Now. I'm your host, Lauren vocal Bam, a researcher and writer. Here at How Stuff Works. Every week, I'm bringing you three stories from our team about the weird and wondrous advances we've seen in science, technology, and culture. This week, there's some science that says drivers who wait until the last second to merge out of an ending lane are actually in the right and unrelated researchers have built a humanoid robot that can do push
ups and cool itself off by sweating. But first, Tex Stuff host Jonathan Strickland, via our freelance writer David Ruse, debunks a few myths about the care and feeding of smartphone batteries. There's a lot of conflicting information out there, but we're here to straighten things out. You've probably taken note of all the talk about smartphones and lithium ion batteries, so we thought we'd take this opportunity to address three burning questions. Question one, isn't a bad idea to leave
your phone plugged in overnight? You might have heard that if you leave your phone plugged in for too long, it will damage the battery in some way. But assuming your charger is in proper working order, there's nothing to worry about. Smartphone battery stopped charging once they hit a limit. It's as if your phone is already unplugged, so good news.
As long as your charger is working correctly, you don't have to set an alarm for the middle of the night so that you don't accidentally overcharge your smartphone into the incredible hulk. Question two, should you run your smartphone's battery out completely before recharging it. You've probably heard that batteries have a limited number of power cycles. This represents the number of times a battery can discharge and recharge before it loses so much capacity then it's pretty much useless.
This is true. Batteries experienced stress through usage, similar to what you'd see in a mechanical system. Eventually the battery wears out, But recharging your phone when it's at say capacity doesn't represent a full charge. It's not like you lose one cycle every time you plug in your phone. That means you don't need to discharge a battery completely before recharging it. In fact, that would cause more stress to your battery, wearing it out faster. Experts suggest recharging
your battery when it's between forty and eight capacity. This will decrease the amount of stress the battery experiences as it discharges and recharges. For some of us, this means recharging our phones several times throughout the day. If you can't do that, don't sweat it. Most of us replace our phones before we've significantly whittled down battery capacity. And now question three, how does heat affect battery performance? Not great, bob.
Heat will reduce a battery's capacity faster than going through lots of charging cycles in a short time. That means when you fully recharge your smartphone, you'll have fewer hours of operation because the battery won't be able to store as much energy as it did previous sleep. So don't leave your smartphones sitting out in the sun or in a hot car, or I don't know, on the stove
or something. It's better. Next up step, editor Christopher Hasiotus and freelancer Jescelin Shields explain how one annoying traffic behavior turns out to be for the good of all of us. Merging lanes at the last possible second isn't just more efficient, it's safer To imagine you're driving down the road, and all of a sudden you see a brightly colored sign announcing lane closed in one thousand feet. You've got a couple of options. One, immediately turn on your blinker and
wait until someone in the next lane lets you in. Two, just stay in your lane and wait for all the plaite people to get out of your way. Then zoom to the front of the line and merge at the last moment, right where the lane closes. Watches people who merge hurley rage in your general direction, silent behind their
glass windows, but faces twisted in fury. To most people, the first option seems more courteous and patient, less selfish, but study upon study proves the upstanding early mergers among us are just creating a single slow line of traffic that's not only frustrating for drivers, it's inefficient. That's because by merging early, we minimize the amount of usable road, leaving a long swath of perfectly good street capacity open
and unused. What we all should be doing is called the late merge zipper system, and by the way, the Germans naturally have their own word for it, rice verst loose system. In this system, every car in the lane that's ending drives all the way up to the front of the line and takes turns merging with the other lane of traffic. From above, it looks a bit like
the teeth on a zipper coming together. Because the system uses all the available road space for as long as possible, it cuts congestion by according to recent studies from various US state departments of Transportation and as well as the Federal Highway Administration. The late merge zipper system also reduces crashes because it keeps all traffic moving at the same rate of speed, rather than having some cars going slow to merge early while others zoom passed them. So why
don't we all just zipper merge at the last minute? Already? The problem is, of course, that our driving habits are baked in pretty deep. But to help steer us to a more rational place, some states are shelling out big bucks to actually retrain their drivers to use the zipper merge. Colorado and Minnesota have been working on encouraging the late merge zipper for a decade, already, followed by Washington, Missouri in Kansas, and even earlier this year, Missouri launched its
own public education campaign. Will this efficient and safe merging technique find a place in our traffic habits. Minnesota Radio's Bob Collins reflected after his state implemented its campaign, saying the zipper merge is going to be this centuries conversion to the metric system in the seventies great idea made perfect sense and was dead on arrival. However, change could
be on its way thanks to a generational shift. A two thousand thirteen Minnesota survey found that only eight percent of senior drivers felt comfortable with the late March zipper system. On the other hand, among drivers aged to thirty four, a full fort of the young population are okay zipping up for common sense and the common good. Finally, this week, I'm bringing you a story from our freelance writer Patrick Jake Tiger about a robot built to manage the heat
from its machinery by sweating. It's only gross and or hilarious until you start thinking about how efficient biomimicry can be. When you physically exert yourself, you break a sweat. You've probably noticed this that dripping is a biological mechanism that keeps your body from overheating when the water secreted out of your sweat glands evaporates, it draws off heat and cools you down. Now, if a machine does something strenuous, it has to get rid of the resulting heat energy too.
In the past, engineers have relied upon fans, motors, and radiators to cool robotic gadgetry. But those solutions are pretty bulky, and when you're talking about robotic gadgetry that mimics living creatures movements, bulky equals cumbersome. That's why University of Tokyo j s K Lab researchers, who are designing robots with muscular and skeletal systems based on the human body, have come up with a solution to the heat problem that's
either ingenious or obvious. They've created a robot that uses sweat to cool itself. The robot, named Kenoto, was presented at the International Conference on Intelligent Robots and Systems in October. It's a five and a half foot tall, hundred and twenty three pound automaton, which is one point seven ms and about fifty six ks for our metric friends. It's stuffed with circuitry and a hundred and eight motors that
need to remain relatively cool to function. Optimally. To do that, the designers created a system of channels that allow water to run through the robot's body and then evaborate out from its metal skin. To accomplish that, the engineers three D printed a highly permeable aluminum frame with a spongelike array of tiny gaps and tunnels through which water can trickle.
Ken Godo has to be kept constantly hydrated for the cooling to be effective, just like you or me, but ken Godo only needs about half a cup of water per day, far less than a human. To demonstrate how well the system works, researchers had the robot do push ups for eleven minutes straight, which it managed without overheating.
The whole thing looks well a lot like you'd expect to push up maniac robot to look, which is to say, something like a Terminator T eight hundred skeleton, except it's ropey muscles are more puffy than sleek, and they gave it a face based in classic manga think Samu Tezuka, but more Buddha than Astro Boy. For anyone who doesn't speak fluent nerd, there's a video on now dot how stuff works dot com with a visual and of course, the j s K Lab isn't just interested in making
robots that do push ups. Lots of their research is bent toward designing bots that are humanoid enough to move with ease around space. Is built for humans like the homes of the elderly and other people who need help with housework or around offices. Do you think how stuff Works would buyas a robot that delivers our inter office mail, sets up teleconferencing, and microwaves our luncheons. That's our show for this week. Thank you so much for tuning in.
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