car

244 Articles

Amphibious Dragster Drives On Water

November 17, 2022 by No comments

Dragsters are typically about peak performance on a tarmac drag strip. [Engineering After Hours] took a different tack, though, building a radio-controlled amphibious dragster intended to cross small bodies of water.

The build is based on a Traxxas Raptor RC car. However, it’s been heavily reworked from a pickup-like design to become a dragster with a motor mounted in the rear. It’s also been fitted with a foam underbody to allow it to float when stationary. The rear tires have been replaced with 3D-printed versions with large paddles, which provide propulsion in the water.

Initial tests showed the car struggled to make progress in the water, as the paddle tires tended to drag the rear end deeper under water. The tiny dragster tires up front didn’t help it steer, in water either. Large foam discs were added to the front tires to enable them to act as better rudders.

Fitted with its water tires and foam floatation aids, the car can only drive slowly on land, but [Engineering After Hours] points out this is enough to call it amphibious. It does a better job at skittering around on water, and it was able to cross a local pond at low speed.

We’ve seen some other creative techniques for making amphibious vehicles, like these crazy star-shaped wheels. Video after the break.

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Lamp Flashing Module Is Perfect For Automotive Use

October 1, 2022 by 17 Comments

Modern cars tend to have quite advanced lighting systems, all integrated under the control of the car’s computer. Back in the day, though, things like brake lights and indicators were all done with analog electronics. If your classic car needs a good old-fashioned flasher module, you might find this build from [DIY Guy Chris] useful.

It’s an all-analog build, with no need for microcontrollers or other advanced modern contrivances. Instead, a little bipolar PNP transistor and a beefier NPN MOSFET as an oscillator, charging and discharging a capacitor to create the desired flashing behavior. Changing the size of the main capacitor changes the flash rate. The MOSFET is chosen as running 12 volt bulbs requires a decent amount of current. The design as drawn is intended to run up to eight typical automotive bulbs, such as you might find in indicator lamps. However, [Chris] demonstrates the circuit with just four.

Flasher circuits were in regular use well into the 1990s. The original Mazda Miata has a very similar circuit tucked up under the dashboard to run the turn signals. These circuits can be hard to find for old cars, so building your own may be a useful workaround if you’re finding parts hard to come by. Video after the break.

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Coils In The Road Could Charge EVs While Driving

August 17, 2022 by 131 Comments

One of the primary issues with EVs is that you need to pull over and stop to get a charge. If there isn’t a high-speed DC charger available, this can mean waiting for hours while your battery tops up.

It’s been the major bugbear of electric vehicles since they started hitting the road in real numbers. However, a new wireless charging setup could allow you to juice up on the go.

Electric Highways

Over the years, many proposals have been made to power or charge electric vehicles as they drive down the road. Many are similar to the way we commonly charge phones these days, using inductive power transfer via magnetic coils. The theory is simple. Power is delivered to coils in the roadway, and then picked up via induction by a coil on the moving vehicle.

Taking these ideas from concept into reality is difficult, though. When it comes to charging an electric vehicle, huge power levels are required, in the range of tens to hundreds of kilowatts. And, while a phone can sit neatly on top of a charging pad, EVs typically require a fair bit of ground clearance for safely navigating the road. Plus, since cars move at quite a rapid pace, an inductive charging system that could handle this dynamic condition would require huge numbers of coils buried repeatedly into the road bed. Continue reading “Coils In The Road Could Charge EVs While Driving” →

Probing CAN Bus For EV Battery Info

July 27, 2022 by 8 Comments

The widespread adoption of the CAN bus (and OBD-II) in automobiles was largely a way of standardizing the maintenance of increasingly complicated engines and their needs to meet modern emissions standards. While that might sound a little dry on the surface, the existence and standardization of this communications bus in essentially all passenger vehicles for three decades has led to some interesting side effects, like it’s usage in this project to display some extra information about an electric car’s battery.

There’s not a ton of information about it, but it’s a great proof-of-concept of some of the things CAN opens up in vehicles. The build is based on a Citroën C-Zero (which is essentially just a re-badged Mitsubishi i-MiEV) and uses the information on the CAN bus to display specific information about the state of charge of the battery that isn’t otherwise shown on the car’s displays. It also includes a build of a new secondary display specifically for this purpose, and the build is sleek enough that it looks like a standard part of the car.

While there are certainly other (perhaps simpler) ways of interfacing with a CAN bus, this one uses off-the-shelf electronics like Arduino-compatible microcontrollers, is permanently installed, and has a custom case that we really like. If you’re just starting to sniff around your own vehicle’s CAN bus, there are some excellent tools available to check out.

Thanks to [James] for the tip!

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The Surprisingly Manual Process Of Building Automotive Wire Harnesses

July 27, 2022 by 115 Comments

Even from the very earliest days of the automobile age, cars and trucks have been hybrids of mechanical and electrical design. For every piston sliding up and down in a cylinder, there’s a spark plug that needs to be fired at just the right time to make the engine work, and stepping on the brake pedal had better cause the brake lights to come on at the same time hydraulic pressure pinches the wheel rotors between the brake pads.

Without electrical connections, a useful motor vehicle is a practical impossibility. Even long before electricity started becoming the fuel of choice for vehicles, the wires that connect the computers, sensors, actuators, and indicators needed to run a vehicle’s systems were getting more and more complicated by the year. After the engine and the frame, a car’s wiring and electronics are its third most expensive component, and it’s estimated that by 2030, fully half of the average vehicle’s cost will be locked in its electrical system, up from 30% in 2010.

Making sure all those signals get where they’re going, and doing so in a safe and reliable way is the job of a vehicle’s wire harnesses, the bundles of wires that seemingly occupy every possible area of a modern car. The design and manufacturing of wire harnesses is a complex process that relies on specialized software, a degree of automation, and a surprising amount of people-power.

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DIY Airless Tires Work Surprisingly Well

June 30, 2022 by 47 Comments

Airless tires have been “a few years away” from production for decades now. They’re one of the automotive version of vaporware (at least those meant for passenger vehicles), always on the cusp of being produced but somehow never materializing. They have a number of perks over traditional air-filled tires in that they are immune to flats and punctures, and since there aren’t any airless tires available at the local tire shop, [Driven Media] decided to make and test their own.

The tires are surprisingly inexpensive to make. A few pieces of drainage tubing of varying diameters, cut to short lengths, and then bolted together with off-the-shelf hardware is all it takes, although they note that there was a tremendous amount of hardware needed to fasten all the pipe lengths together. With the structure in place they simply cut a tread off of a traditional tire and wrapped it around each of the four assemblies, then bolted them up to their Caterham street-legal race car for testing.

While the ride quality was notoriously (and unsurprisingly) rough and bumpy, the tires perform admirably under the circumstances and survive being driven fairly aggressively on a closed-circuit race course. For such a low price and simple parts list it’s shocking that a major tire manufacturer like Michelin hasn’t figured out how to successfully bring one to a light passenger car yet.

Thanks to [Itay] for the tip!

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Defeat Your Car’s Autostop Feature With A Little SwitchBot

May 18, 2022 by 207 Comments

These days, many new cars come with some variant of an “auto-stop” feature. This shuts down the car’s engine at stop lights and in other similar situations in order to save fuel and reduce emissions. Not everyone is a fan however, and [CGamer_OS] got sick of having to switch off the feature every time they got in the car. So they employed a little robot to handle the problem instead.

The robot in question is a SwitchBot, a small Internet of Things tool that’s highly configurable for pressing buttons. It’s literally a robot designed to press buttons, either when remotely commanded to, or when certain rules are met. It can even be configured to work with IFTTT.

In this case, the Switchbot is set up to activate when [CGamer_OS]’s phone is placed in phone mount, where it scans an NFC tag. When this happens, Switchbot springs into action, switching off the autostop function. It was set up this way to avoid Switchbot hitting the button before the car has been started. Instead, simply popping the smartphone in the cradle activates the ‘bot.

It’s a rather creative use of the SwitchBot. They’re more typically employed to turn on dumb devices like air conditioners or heaters that can otherwise be difficult to control via the Internet. However, it works well, and means that [CGamer_OS] didn’t have to make any permanent modifications to the car.

The design of the SwitchBot reminds us of the Useless Box, even if in this case it has an actual purpose. Video after the break.

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