An Ultra Low Power Dash Cam

April 3, 2023 by Matthew Carlson 19 Comments

Dash cameras are handy as they provide a video recording of interactions on the road. However, their utility comes from the fact that they are always recording while driving. This always-on means power draw. [Kuzysk] took it upon himself to cut that power draw by a factor of almost 70x.

He found his existing dash cam from MiVue consumed 3.5mA in idle which works out to be a whole amp-hour every 12 days. The custom version takes just 50uA which means it will draw an amp-hour in two years. The brains of the chip are formed by an ATmega328 and an LM2596M, which is a simple step-down regulator. Interestingly, [Kuzysk] purchased clones and original chips and found that the cheaper clones had a lower switching frequency but a much lower power draw. Programming an Arduino bootloader onto the board is fairly straightforward and [Kuzysk] kindly provides his code. It can detect the ACC voltage that’s on when the engine is on and is powered by a permanent 12v connection to the battery.

Overall it’s a straightforward hack that goes through rolling your own Arduino, optimizing for low power, and putting it all together into a polished project. Perhaps for the next version, he can use the ATmega to control a cheaper camera and make it smart.

Thanks to [Microchip makes] and [Abe] for the tip!

Will Carmakers Switch Clay For Computers?

March 3, 2023 by Al Williams 47 Comments

The 3D printing revolution has transformed a lot of industries, but according to [Insider Business] the car industry still uses clay modeling to make life-sized replicas of new cars. The video below shows a fascinating glimpse of the process of taking foam and clay and making it look like a real car. Unlike the old days, they do use a milling machine to do some rough work on the model, but there’s still a surprising amount of manual work involved. Some of the older film clips in the video show how hard it was to do before the CNC machines.

The cost of these models isn’t cheap. They claim that some of the models have cost $650,000 to create. We assume most of that is in salaries. Some models take four years to complete and a ton of clay.

Continue reading “Will Carmakers Switch Clay For Computers?” →

A grey car sits in the background out of focus, its front facing the camera. It sits over an asphalt roadway with a metal rail extending from the foreground to behind the car in the distance. The rail has a two parallel slots and screws surrounding the slots running down the rail.

What Happened To Sweden’s Slot Car EV Road?

March 1, 2023 by Navarre Bartz 60 Comments

Many EVs can charge 80% of their battery in a matter of minutes, but for some applications range anxiety and charge time are still a concern. One possible solution is an embedded electrical rail in the road like the [eRoadArlanda] that Sweden unveiled in 2016.

Overhead electrical wires like those used in trolleys have been around since the 1800s, and there have been some tests with inductive coils in the roadway, but the 2 km [eRoadArlanda] takes the concept of the slot car to the next level. The top of the rail is grounded while the live conductor is kept well underground beneath the two parallel slots. Power is only delivered when a vehicle passes over the rail with a retractable contactor, reducing danger for pedestrians, animals, and other vehicles.

One of the big advantages of this technology being in the road bed is that both passenger and commercial vehicles could use it unlike an overhead wire system that would require some seriously tall pantographs for your family car. Testing over several Swedish winters shows that the system can shed snow and ice as well as rain and other road debris.

Unfortunately, the project’s website has gone dark, and the project manager didn’t respond when we reached out for comment. If there are any readers in Sweden with an update, let us know in the comments!

We’ve covered both overhead wire and embedded inductive coil power systems here before if you’re interested in EV driving with (virtually) unlimited range.

Continue reading “What Happened To Sweden’s Slot Car EV Road?” →

LED Air Vent Gauges Are A Tasteful Mod For The Mazda Miata

January 27, 2023 by Lewin Day 23 Comments

Anyone in the JDM scene can tell you, round air vents are prime real estate for round analog gauges. If you want a gauge but don’t want to block your vent, you could consider building these LED vent gauges from [ktanner] instead.

The design is simple. It relies on 3D printing a replacement bezel for the Mazda Miata’s stock round air vents. This bezel is designed to hold a NeoPixel ring from Adafruit. When built with the optional laser-cut diffuser, the parts have a near-stock look when the LEDs are turned off. It’s a classy, stealthy mod – exactly the sort of thing Miata owners need but never seem to have! (Author Note: don’t be mad, I was once one of you!)

With 24 addressable RGB LEDs, it’s possible to display all kinds of data by turning the LEDs on and off and varying the colors. For example, you could readily build a boost gauge that turns on more LEDs at higher boost pressure. It could then be set up to flash red in the event that you surpass safe thresholds. [ktanner] hasn’t specified any particular microcontroller for the setup — but just about any part you like can be used to drive NeoPixels, after all.

If you’re new to NeoPixels, you might find a simulator useful for developing your projects. Meanwhile, if you’re doing similar work on other cars, be sure to hit us up on the tipsline!

A Simple Air Suspension Demo With Lego Technic

January 25, 2023 by Lewin Day 19 Comments

The most common suspension systems on automobiles rely on simple metal springs. Leaf spring and coil spring designs both have their pros and cons, but fundamentally it’s all about flexing metal doing the work. Air suspension works altogether differently, employing gas as a spring, as demonstrated by this simple Lego build from [JBRIX].

The suspension system is employed on a Lego Technic car, with a relatively unsophisticated design. The car has no real form of propusion, and serves solely to demonstrate the air suspension design. They may look like dampers, but the system is actually using Lego pneumatic pistons as springs for each wheel. The pistons are connected to the upper control arm of a double wishbone suspension setup. Each piston is pneumatically connected to a main reservoir. With the reservoir, and thus the pistons, pressurized, the suspension system can support the weight of the car. If a bump perturbs a wheel, the piston compresses the air in the system, which then returns the piston to its original position, thus serving as a spring. If the reservoir is vented, the suspension collapses. Air springs on real, full-sized automobiles work in basically the same way. However, they usually have a separate reservoir per corner, keeping each wheel’s suspension independent.

Overall, if you’re working on some kind of Lego rambler, you might find this suspension concept useful. Alternatively, you might simply find it good as a learning aid. If you want to learn more about oddball suspension systems, we can help there too. Video after the break.

Continue reading “A Simple Air Suspension Demo With Lego Technic” →

RC Car Gets F1-Style DRS Rear Wing

January 21, 2023 by Lewin Day 1 Comment

DRS, or the Drag Reduction System, has become a key part of Formula 1 in the past decade. [Engineering After Hours] decided to implement the same system on an RC car instead.

The DRS system was implemented in Formula 1 to increase passing in the series. By moving a flap in the rear wing of the race cars, drag could be reduced, allowing a car to attain a higher top speed on the straights. The racing series limited the activation of the DRS wing to only cars following closely behind another. This artificially enabled them to gain a speed boost over the car in front to aid passing.

[Engineering After Hours] wanted to see if a tiny wing on a small RC car could work the same way. It would fundamentally come down to whether moving a tiny wing element would appreciably change the car’s drag or not. Naturally, on such a small scale, attaining high speeds would be necessary to detect much difference. At lower speeds, the difference in drag would likely be too negligible to notice.

The RC-scale DRS system fundamentally does work. With DRS engaged, flattening out the rear wing elements noticably reduced downforce at the rear. With the DRS not engaged, though, the rear wing on the car was creating so much downforce that the car was squatting at the rear and occasionally flipping end over end. [Engineering After Hours] didn’t get any top speed measurements, but estimated that the wing could potentially increase top speed by up to 7 mph with the DRS enabled.

We’ve seen [Engineering After Hours] bring other fun motorsport tech to RC cars before, too, like this amazing fan car build.

Continue reading “RC Car Gets F1-Style DRS Rear Wing” →

Cassette Player Cupholder Is A Useful But Risky Idea

January 20, 2023 by Lewin Day 36 Comments

The cup was invented in 1570 BC. Despite this, infuriatingly, the cupholder didn’t become common in the automotive world until the early 2000s. Cars built in the years PCH (pre-cupholder) typically also had tape decks. Noticing this relationship, [thephatmaster] designed this useful cassette-deck cupholder accessory.

The design is simple, consisting of a 3D printed ring with a tab that neatly slides into an automotive stereo’s cassette slot. The design does require that the tape deck be empty prior to inserting the cup holder. Given that few cassette players from that era still work, this isn’t much of a drawback. Of course, if you really do need tunes, it wouldn’t be too difficult to integrate a Bluetooth cassette adapter into the printed design.

[thephatmaster] uses the cupholder in a Mercedes W202, and has posted a special inclined version to suit this model. The creator also notes that using it on vehicles like the Mercedes W210 can be a risk. The cupholder typically places the beverage directly above the transmission lever, where any spills can damage switches or other important electronics. Also, the cupholder isn’t designed to work with vertical tape decks, though modification for this layout may be possible.

This build may look silly or pointless to some. But if you’ve ever tried to pull a U-turn in an old manual car while precariously cradling a steaming latte between your legs, you’ll clearly see the value here. It only has to save one pair of pants before it’s paid for itself.

We’ve seen some other creative cupholder hacks before too, like this nifty laptop holder. If you’ve whipped up your own nifty car hacks, send them into the tipsline.