An open engine bay for a small car. The wheels are off so the hubs and brakes are visible to the side and the electric motor mounted on top of the vehicle's original engine block is in the center of the image.

A Different Approach To EV Conversions

June 28, 2023 by Navarre Bartz 53 Comments

While there are a lot of exciting electric vehicles finally coming to market, many of us feel nostalgic for the fossil cars of our youth. [Mihir Vardhan] restored his grandfather’s car with an unusual gas-to-EV conversion.

While this conversion starts in the usual fashion by pulling out the gas engine, [Vardhan] takes a different tack than most by not just bolting an electric motor up to the transmission. Instead, he and his crew removed the head and pistons from the petrol burner and bolted the electric motor to the top on an L-shaped bracket. Using the timing belt to transfer power to the crankshaft, there is no need to figure out additional motors for the A/C compressor or power steering pump, greatly simplifying implementation.

[Vardhan] did need to add a vacuum pump for the braking system and used a DC/DC converter to step down the 72V traction battery voltage to the 12V needed to charge the accessory battery. While it doesn’t exactly boast the performance of a Tesla, his bargain-basement conversion does yield a converted vehicle that can get around town for only around $3k US, even if it does mean your EV still needs oil changes. We think this could work even better on a vehicle with a timing chain instead of a belt, but it’s certainly an interesting way to go about the conversion process.

We’ve covered our fondness for EV conversions in the past for cars, motorcycles, and boats if you’d like to dig deeper. Have your own EV conversion you think we should cover? Send us a tip!

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An Unexpected Upset In EV Charging Standards

June 21, 2023 by Navarre Bartz 52 Comments

Last November, Tesla open-sourced parts of its charging infrastructure, not-so-humbly unveiling it as the North American Charging Standard (NACS). It’s finally taking off with a number of manufacturers signing on.

Companies launching “standards” based on their previously proprietary technology in opposition to an established alternative usually leads to standards proliferation. However, with recent announcements from Ford, GM, and Rivian that they would begin supporting NACS in their vehicles, it seems a new dominant standard is supplanting CCS (and the all-but-dead CHAdeMO) in North America.

As Tesla already has the most extensive charging network on the continent and has begun opening it up for other EVs, it makes sense that other marques would want to support NACS, if nothing else to satiate customer demand for a dead-simple charging experience. Dongles are annoying enough for plugging in an external monitor. Having to mess with one while handling high-power electrical connections is less than ideal, to say the least.

If you want to add NACS to your own EV project, the standard is here. We’ve discussed some of the different standards before as well as work toward wirelessly charging EVs (besides the inductive charger on the EV1). It certainly seems like the time to get in on the ground floor of an EV charging empire with an army of Charglas.

Using Sonar To Measure Traffic Speeds

June 19, 2023 by Bryan Cockfield 21 Comments

One of the most common ways of measuring the speed of a vehicle is by using radar, which typically involves generating radio waves, directing them at a moving vehicle, and measuring the various ways that they return to the device. This is a tried-and-true method, but can be expensive and technically complex. [GeeDub] wanted an easier way of measuring vehicles passing by his home, so he switched to using sonar instead to measure speeds based on the sounds the cars generate themselves.

The method he is using is similar to passive sonar in submarines, which can locate objects underwater based on the sounds they produce. After a false start attempting to measure Doppler shift, he switched to time correlation using two microphones, essentially using stereo audio input to detect subtle differences in arrival times of various sounds to detect the positions of passing vehicles. Doing this fast enough and extrapolating the data gathered, speed information can be calculated. For the data gathering and calculation, [GeeDub] is using a Raspberry Pi to help keep costs down, and some further configuration of the microphones and their power supplies were also needed to ensure quality audio was gathered.

With the system in place in a window, it detected around 9,000 vehicles over a three-day period. The software generates a normal distribution of vehicle speeds for this time, with the distribution centered on around 35 MPH, slightly above the posted speed limit of 30. As long as there’s a clear line of sight to the road using this system it’s just as effective as some other passive systems we’ve seen to measure vehicle speed. Of course, active speed measurement systems are not out of the realm of possibility if you’re willing to spend a little more.

Hyundai Is Doomed: Porting The 1993 Classic To A Hyundai Head Unit

June 11, 2023 by Maya Posch 6 Comments

In the natural order of the world, porting DOOM to any newly unlocked computing system is an absolute given. This a rule which [greenluigi1] understands all too well, leading to presumably the first Hyundai to be equipped with this all-time classic on its infotainment system. This follows hot on the trail of re-hacking said infotainment system and a gaggle of basic apps being developed for and run on said head unit (being the part of the infotainment system on the front dashboard). Although it is a Linux-based system, this doesn’t mean that you can just recompile DOOM for it, mostly because of the rather proprietary system environment.

To make life easy, [greenluigi1] picked doomgeneric as the version to port. The main selling point of this project is that it only requires the developer to implement five functions to support a new platform, which then ‘just’ left figuring out how to do this on a head unit. Two of these (DG_SleepMs() and DG_GetTicksMS()) could be copied verbatim from the X11/xlib port, but the remaining three required a bit of sleuthing.

Where things go sideways is with keeping the head unit’s Helix window manager happy, and stick to the limited ways a GUI application can be launched, including the way arguments are passed. For the PoC, it was decided to just hardcode these arguments and only register the game with Helix using an .appconf configuration file. When it came to drawing pretty graphics on the screen, this was decidedly easier since the system uses Qt5 and thus offers the usual ways to draw to a QPixmap, which in this case maps to the framebuffer.

After a few playful sessions with the head unit’s watchdog timer, [greenluigi1] found himself staring at a blank screen, despite everything appearing to work. This turned out to be due to the alpha channel value of 0 that was being set by default, along with the need for an explicit refresh of the QPixmap. Up popped DOOM, which left just the implementation of the controls.

In order to start the game, you have to literally buckle up, and the steering wheel plus media control buttons are your inputs, which makes for a creative way to play, and perhaps wear some bald spots onto your tires if you’re not careful. If you’d like to give it a shot on your own ride, you can get the project files on GitHub.

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Nissan 300zx Dash Given A New Language

June 8, 2023 by Matthew Carlson 6 Comments

You don’t have to be a car enthusiast to recognize that the 1984 Nissan 300x dash is a work of art. The graceful swoops and multisegment VFDs evoke an aesthetic that reminds us of a particular era. Rather than replace his dash with something drab and modern, [Evan] modified his dash to accept input from newer devices. Many of the sensors that feed directly into the dash are becoming harder to find as the years wear on, and rather than spoof every old device, [Evan] looked at each gauge.

Temperature and oil pressure are variable resistance sensors, and by removing half the voltage divider, it becomes a variable voltage sensor, as modern temperature sensors can output a voltage from 0 to 5. The tachometer required tracing the signal through the PCB as it expects a pulse every time a cylinder fires. By simulating cylinder pulses with a function generator, [Evan] found the filtering circuit and the microcontroller pin monitoring it. An optoisolator to protect the delicate MCU makes it easy to pipe the signal directly in.

Of course, not everything needed to be modified. A vacuum sensor provides a signal to the dash to indicate how much power the engine produces, which is pretty easy to spoof with a teensy connected to the CAN bus. All these mods are easily reversible and allow [Evan] to keep rocking the iconic dash with a more modern engine.

It’s an incredible hack that offers a view into how to trace, understand, and hack old electronics. Of course, if you’re keeping old built-in car bits, why not keep the carphone but connect it to your smartphone?

Photo of the head unit , with "Hacked by greenluigi1" in the center of the UI

Hacking A Hyundai Ioniq’s Infotainment System Again After Security Fixes

June 8, 2023 by Maya Posch 15 Comments

These days modern cars are nothing if not a grouping of networked software held together by bits of hardware. This is reflected not only in the rapidly increasing number of ECUs, but also infotainment systems and all-glass cockpits. For better or worse, this offers many exciting hacking possibilities, which [greenluigi1] was more than happy to explore with their new 2021 Hyundai Ioniq SEL last year. Naturally, Hyundai then proceeded to ‘fix’ these vulnerabilities, offering the exciting chance to test the Hyundai engineers’ homework, and proceed to bypass it again.

When we last left off in [greenluigi1]’s adventures, the Hyundai D-Audio 2V Linux-based infotainment system (formally called in-vehicle entertainment, or IVI) in question had been convinced to run custom applications after a fair bit of effort to get root access via the Engineering Menu and some firmware image hacking. Joyous hacking and exploration of the car’s CAN network and RPC messaging system ensued. Then Hyundai released a new firmware image, after months of silence and all old firmware images pulled from the download page.

In this new firmware image, big changes were visible right off the bat, with two different ZIP files instead of the single one from before. One of these ZIP files also couldn’t be decrypted any more with the old key. Unfortunately for Hyundai, the curse of backwards compatibility with older IVIs meant that the ZIP targeting headunits running the older firmware also contained the key for the new ZIP file.

Other changes included some further obfuscation to this key and the public key used for firmware hash verification, which also involved using a Micom RPC call via the CAN bus to obtain some vehicle specific information. Unfortunately, this is where Hyundai’s engineers seemed to have stopped copying reference code samples, and used a unique RSA private key to sign firmware images with. Fortunately, they did not bother to check whether the updater actually always verifies the signature, allowing for unsigned code to be installed.

All in all, a fascinating bit of reverse-engineering and sheer stubborn persistence, just so that the IVI that’s in your car can run the applications which you developed. We’re looking forward to the next installments in this series as the ball is once again firmly in Hyundai’s court.

Converting On-Grid Electronics To Off-Grid

May 11, 2023 by Dave Rowntree 54 Comments

Husband and wife team [Jason & Kara] hail from Canada, and in 2018, after building their own camper, sold up their remaining earthly goods and headed south. If you’re not aware of them, they documented their journey on their YouTube channel, showing many interesting skills and hacks along the way. The video we’re highlighting today shows a myriad of ways to power all the DC-consuming gadgets this they lug along with them.

LiFePO4 batteries are far superior to lead acid for mobile solar installations.

Their heavily modded F-550 truck houses 12kWh of LiFePO4 batteries and a 1.5kW retractable solar array, with a hefty inverter generating the needed AC power. They weren’t too happy with the conversion losses from piles of wall warts that all drained a little power, knowing that the inverter that fed them was also not 100% efficient. For example, a typical laptop power brick gets really hot in a short time, and that heat is waste. They decided to run as much as possible direct from the battery bank, through different DC-DC converter modules in an attempt to streamline the losses a little. Obviously, these are also not 100%

efficient, but keeping the load off the inverter (and thus reducing dependency upon it, in the event of another failure) should help stem the losses a little. After all as [Jason] says, Watts saved are Watts earned, and all the little lossy loads add up to a considerable parasitic drain.

One illustration of this is their Starlink satellite internet system consumes about 60W when running from the inverter, but only 28W when running direct from DC. Over the course of 24 hours, that’s not far off 1kWh of savings, and if the sun isn’t shining, then that 12kWh battery isn’t going to stretch as far.

There are far too many hacks, tips, and illustrations of neat space and power-saving solutions everywhere, to write here. Those interested in self-build campers or hacking a commercial unit may pick up a trick or two.

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