When electric cars first started hitting the mainstream just over a decade ago, most criticism focused on the limited range available and the long recharge times required. Since then, automakers have been chipping away, improving efficiency here and adding capacity there, slowly pushing the numbers up year after year.
Models are now on the market offering in excess of 400 miles between charges, but lurking on the horizon are cars with ever-greater range. The technology stands at a tipping point where a electric car will easily be able to go further on a charge than the average driver can reasonably drive in a day. Let’s explore what’s just around the corner.
Continue reading “Longer Range EVs Are On The Horizon”
A beach is always a relaxing summer vacation destination, a great place to hang out with a drink and a book or take a swim in the ocean. For those who need a more active beach-going activity with an electronics twist, though, metal detecting is always a popular choice too. And, of course, with an Arduino and some know-how it’s possible to build a metal detector that has every feature you could want from even a commercial offering.
This build comes to us from [mircemk] who built this metal detector around an Arduino Nano and uses a method called induction balance detection to find metal. Similar to how radar works, one coil sends out a signal and the other listens for reflections back from metal objects underground. Building the coils and determining their resonant frequency is the most important part of this build, and once that is figured out the rest of the system can be refined and hidden treasure can easily be unearthed.
One of the more interesting features of this build is its ability to discriminate between ferrous and non-ferrous metals, and it can detect large metal objects at distances of more than 50 cm. There are improvements to come as well, since [mircemk] plans to increase power to the transmission coil which would improve the range of the device. For some of [mircemk]’s other metal detectors, be sure to check out this one which uses a smartphone to help in the metal detection process.
Continue reading “Arduino Finds Treasure”
While we’re certainly not denying that smoke detectors are useful, there’s a certain kind of tragedy to the fact that most of them will never realize their true purpose of detecting smoke, and alerting us to a dangerous fire. On the other hand, [Ben] really unlocks the potential hidden deep in every smoke detector with his latest project which uses the smoke-detecting parts of a smoke detector to turn on the exhaust fan over his stove.
The project didn’t start with the noble aim of realizing the hidden and underutilized quiescent nature of a smoke alarm, though. He wanted his range exhaust fan to turn on automatically when it was needed during his (and his family’s) cooking activities. The particular range has four speeds so he wired up four relays to each of the switches in the range and programmed a Particle Photon to turn them on based on readings from an MQ-2 gas-detecting sensor.
The sensor didn’t work as well as he had hoped. It was overly sensitive to some gasses like LPG which would turn the range on full blast any time he used his cooking spray. Meanwhile, it would drift and not work properly during normal cooking. He tried disabling it and using only a temperature sensor, which didn’t work well either. Finally, he got the idea to tear apart a smoke detector and use its sensor’s analog output to inform the microcontroller of the current need for an exhaust fan. Now that that’s done, [Ben] might want to add some additional safety features to his stovetop too.
When we think of physics experiments, we tend to envision cavernous rooms filled with things like optical benches, huge coils in vacuum chambers, and rack after rack of amplifiers and data acquisition hardware. But it doesn’t have to be that way – you can actually perform laser interferometry with a single component and measure sub-micron displacements and more.
The astute viewer of [Ben Krasnow]’s video below will note that in order to use the one component, a laser diode, as an interferometer, he needed a whole bunch of support gear, like power supplies, a signal generator, and a really, really nice mixed-signal oscilloscope. But the principle of the experiment is the important bit, which uses a laser diode with a built-in monitoring photodiode. Brought out to a third lead, older laser diodes often used these photodiodes to control the light emitted by the laser junction. But they also respond to light reflected back into the laser diode, and thanks to constructive and destructive interference, can actually generate a signal that corresponds to very slight displacements of a reflector. [Ben] used it to measure the vibrations of a small speaker, the rotation of a motor shaft, and with a slight change in setup, to measure the range to a fixed target with sub-micron precision. It’s fascinating stuff, and the fact you can extract so much information from a single component is pretty cool.
We really like [Ben]’s style of presentation, and the interesting little nooks and crannies of physics that he finds a way to explore. He recently looked at how helium can kill a MEMS sensor, an equally fascinating topic.
Continue reading “[Ben Krasnow] Builds A One-Component Interferometer”
More and more electric bikes have been rolling out into the streets lately as people realize how inexpensive and easy they are to ride and use when compared to cars. They can also be pedaled like a normal bike, so it’s still possible to get some exercise with them too. Most have a range somewhere around 10-30 miles depending on battery size, weight, and aerodynamics, but with a few upgrades such as solar panels it’s possible to go much, much further on a charge.
[The Rambling Shepherd] had a tricycle (in the US, generally still considered a bicycle from a legal standpoint) that he had already converted to electric with a hub motor and battery, and was getting incredible range when using it to supplement his manual pedaling. He wanted to do better, though, and decided to add a few solar panels to his build. His first attempt didn’t fare so well as the 3D-printed mounts for the panel failed, but with a quick revision his second attempt survived a 50-mile trip. Even more impressive, he only had his battery half charged at the beginning of the journey but was still able to make it thanks to the added energy from the panels.
If you’re thinking that this looks familiar, we recently featured a tandem tricycle that was making a solar-powered trip from Europe to China with a similar design. It has the advantage of allowing the rider to pedal in the shade, and in a relatively comfortable riding position compared to a normal bike. Future planned upgrades include an MPPT charge controller to improve the efficiency of the panels.
Continue reading “Pedal Far With A Solar Powered Tricycle”
In families with three kids, the middle child always seems to get the short end of the stick. The first child gets all the attention for reaching every milestone first, and the third child will forever be the baby of the family, and the middle child gets lost in-between. Something similar happened with the U.S. manned space program in the 60s. The Mercury program got massive attention when America finally got their efforts safely off the ground, and Apollo naturally seized all the attention by making good on President Kennedy’s promise to land a man on the moon.
In between Mercury and Apollo was NASA’s middle child, Project Gemini. Underappreciated at the time and even still today, Gemini was the necessary link between learning to get into orbit and figuring out how to fly to the Moon. Gemini was the program that taught NASA how to work in space, and where vital questions would be answered before the big dance of Apollo.
Chief among these questions were tackling the problems surrounding rendezvous between spacecraft. There were those who thought that flying two spacecraft whizzing around the Earth at 18,000 miles per hour wouldn’t work, and Gemini sought to prove them wrong. To achieve this, Gemini needed something no other spacecraft before had been equipped with: a space radar.
Continue reading “Radar In Space: The Gemini Rendezvous Radar”
Frankencars are built from the parts of several cars to make one usable vehicle. [Jim Belosic] has crossed the (finish) line with his Teslonda. In the most basic sense, it is the body of a Honda Accord on top of the drive train of a Tesla Model S. The 1981 Honda was the make and model of his first car, but it wasn’t getting driven. Rather than sell it, he decided to give it a new life with electricity, just like Victor Frankenstein.
In accord with Frankenstein’s monster, this car has unbelievable strength. [Jim] estimates the horsepower increases by a factor of ten over the gas engine. The California-emissions original generates between forty and fifty horsepower while his best guess places the horsepower over five-hundred. At this point, the Honda body is just holding on for dear life. Once all the safety items, like seatbelts, are installed, the driver and passengers will be holding on for the same reason.
This kind of build excites us because it takes something old, and something modern, and marries the two to make something in a class of its own. And we hate to see usable parts sitting idle.
Without a body, this electric car scoots around with its driver all day, and this Honda doesn’t even need the driver inside.
Continue reading “Car Revival According To Tesla”