A great place to get your feet wet with the data-network-wonderland that is modern-day automobiles is the Car Hacking Village at DEF CON. I stopped by on Saturday afternoon to see what it was all about and the place was packed. From Ducati motorcycles to junkyard instrument clusters, and from mobility scooters to autonomous RC test tracks, this feels like one of the most interactive villages in the whole con.
Unless your car is fresh off the lot, you’ve probably had the experience of riding in a newer car and seeing some feature or function that triggered a little pang of jealousy. It probably wasn’t enough for you to run out and sign yourself up for a new car loan (which is what the manufacturer was hoping for), but it was definitely something you wished your older model vehicle had. But why get jealous when you can get even?
[Saabman] wished his 1999 Saab 9-5 had the feature where a quick tap of the turn signal lever would trigger three blinks of the indicator. Realizing this was an electronic issue, he came up with a way to retrofit this function into his Saab by adding an Arduino Pro Micro to the vehicle’s DICE module.
The DICE (which stands for Dashboard Integrated Central Electronics) module controls many of the accessories in the vehicle, such as the lighting and wipers. In the case of the blinkers, it reads the state of the signal lever switches and turns the blinkers on and off as necessary. After poking around the DICE board, [Saabman] found that the 74HC151 multiplexer chip he was after: the state of the blinker switches could be read from pins 1 and 2, and he’d even be able to pull 5 V for the Arduino off of pin 16.
After prototyping the circuit on a breadboard, [Saabman] attached the Pro Micro to the top of the 74HC151 with some double sided tape and got to work on refining the software side of the project. The Arduino reads the state of the turn signal switches, and if they flick on momentarily it changes the pin from an input to an output and brings it high for three seconds. This makes the DICE module believe the driver is holding the turn lever, and will keep the blinkers going. A very elegant and unobtrusive way of solving the problem.
Hackers aren’t complete strangers to the garage; from printing hard to find parts to grafting in their favorite features from other car manufacturers, this slick Saab modification is in good company.
When working on classic vehicles, and especially when modifying them outside of their stock configurations, things can get expensive. It’s a basic principle in economics: the rarer something is the more money somebody can charge you for it. But if you’ve got the skills and the necessary equipment, you can occasionally save yourself money by custom-fabricating some parts yourself.
After changing the gear ratio in his 1971 Ford F100, [smpstech] needed to adjust his speedometer to compensate. Unfortunately, a commercial speedometer reducer and the new cables to get it hooked up to his dash would have run into the hundreds of dollars, so he decided to try designing and 3D printing his own gearbox. The resulting development process and final product are a perfect example of how even a cheap desktop 3D printer, in the hands of a capable operator, can do a lot more than print out little toy boats.
The gearbox contains a large ring gear driven by a smaller, offset, spur gear. This compact inline package drops the speed of the input shaft by 25.5%, which [smpstech] mentions is actually a bit slower than necessary, but it does give him some wiggle room if he decides to change his tire size.
Even if you’re not looking for a speedometer reducer for a nearly 50 year old truck, there are some lessons to be learned here in regards to 3D printed car parts. The first version of his gearbox, while functional initially, ended up looking like a deflated balloon after being exposed to the temperatures inside the F100’s engine bay. His cheapo PLA filament, which is probably fine for the aforementioned toy boats, simply wasn’t the right material for the job.
[smpstech] then reprinted the gadget in HTPLA, which needs to be annealed after printing to reach full strength. Usually this would involve a low-temperature bake in the oven, but he found that simmering the parts in a pot of water on the stove gave him better control over the temperature. Not only did the HTPLA version handle the under-hood conditions better, it was also strong enough that he was able to use a standard die on the connections for the speedometer cables to create the threads instead of having to model and print them. Definitely a material to keep an eye on if regular PLA isn’t cutting it for you.
This isn’t the first time we’ve seen 3D printed parts used to get a vintage vehicle back on the road. Building these custom parts would have been possible without a 3D printer, of course, but it’s a good example of how the technology can make these types of repairs faster and easier.
[via /r/functionalprint]
Automotive components that have a hidden secondary function are usually limited to cartoons and Michael Bay movies, but this project that [Jesus Echavarria] created for a client is a perhaps as close as we’re likely to get in the near future. The final product certainly looks like a standard automotive relay, but a peek inside the 3D printed case reveals a surprisingly complex little device. It’s still technically a relay, but it uses a PIC microcontroller to decide when it should activate.
[Jesus] was given the task of creating a device that would fit into the relay box of a vehicle, and serve as a battery monitor to fire off at different voltage set points. The client also wanted the ability to configure such things as how long the device would wait before enabling and disabling the alarms once the voltage threshold has been passed. After showing the client an oversize prototype using a PIC16F88 and switching regulator, he got the OK to move on to a smaller and more cost-effective version.
The final hardware makes use of a 78M05 500 mA linear regulator, a PIC16F1824 microcontroller, and a pair of AQY211EH solid state relays. The standard five pin layout used for automotive relays allows the monitor to get power from the vehicle’s battery while providing two output channels that can be switched on and off from the microcontroller. [Jesus] says an agreement with the client prevents him from sharing some elements of the project (like the firmware source code), but he gives enough information that it shouldn’t be too hard to spin up your own version.
With the addition of something like an ESP8266, this could be an easy way to retrofit an older vehicle with “smart” features. As an example, it could potentially allow for controlling the car’s headlights and horn over Wi-Fi. Or you could hack together a theft deterrent system that refuses to power on the starter or fuel pump unless your smartphone enables the relay first.
Most new cars have GPS, rear cameras, and all the other wonders an on-board system can bring. But what if you have an old car? [Fabrice Aneche] has a 2011 vehicle, and wanted a rearview camera. He started with a touch screen, a Raspberry Pi 3, and a camera. But you know how these projects take on a life of their own. So far, the project has two entries in his blog.
It wasn’t long before he couldn’t resist the urge to add a GPS. But that’s no fun without maps. Plus you need turn-by-turn directions. [Fabrice] did a lot of the user interface using Qt5 and QML. He started out running it with X11 but that was slow. It turns out though that Qt5 can drive the Pi’s video directly without using X11, so that’s what he wound up doing. The code that isn’t in QML — mainly dealing with the GPS location — is written in Go, while the code for MOCS (My Own Car System) is on GitHub.
With the incredibly low cost of software defined radio (SDR) hardware, and the often zero cost of related software, there’s never been a better time to get into the world of radio. If you’ve got $30 burning a hole in your pocket, you’re good to go. But as with any engrossing hobby that’s cheap to get into, you run the risk of going overboard eventually.
For example, if the radio gear inside your car approaches parity with the Kelly Blue Book value of said vehicle, you may have been bitten by the radio bug. In the video after the break, [Corrosive] gives us a tour of his antenna festooned Hyundai Accent, that features everything he needs to receive and analyze a multitude of analog and digital radio signals on the go.
He starts with the roof of the car, which is home to five whip antennas (not counting the one from the factory installed AM/FM radio) and two GPS receivers. The ones on the rear of the car feed down into the trunk, where a bank of Nooelec NESDR RTL-SDR receivers will live in a USB hub. He’s only got one installed for test purposes, but he’ll need more for everything he’s got planned. Also riding in the back is a BCD780XLT scanner, which he got cheap on eBay thanks to the fact it had a dead display.
Luckily, where [Corrosive] is going, he won’t need displays. The SDR receivers and the scanner are all controlled from the driver’s seat by way of a Windows 10 tablet. This runs the ProScan software that provides a virtual interface to the BCD780XLT, as well as various SDR interfaces. He’s also got Gpredict for tracking satellites and ADS-B programs like Virtual Radar.
The car’s head unit has been replaced by a rooted Android entertainment system which supports USB host mode. [Corrosive] says it isn’t hooked up yet, but in the future the head unit is going to get its own SDR receiver so he can run programs like RF Analyzer right in the dashboard. We’re willing to bet that this will be the only car in the world that has both a waterfall display and the “Check Engine” light on at the same time.
Even if you aren’t ready to install it in your car, you might like to read up on using multiple SDR receivers for trunked radio or setting up your own ADS-B receiver to get a better idea of what [Corrosive] has in mind once everything is up and running.
Oxford is a city world-famous for its university, and is a must-see stop on the itinerary of many a tourist to the United Kingdom. It features mediaeval architecture, unspoilt meadows, two idylic rivers, and a car plant. That’s the part the guide books don’t tell you, if you drive a BMW Mini there is every chance that it was built in a shiny new factory on the outskirts of the historic tourist destination.
![A 1930s Morris Ten Series II. Humber79 [CC BY-SA 3.0].](https://hackaday.com/wp-content/uploads/2018/05/morris10080809e.jpg)
Morris produced a range of run-of-the-mill saloon cars in this period, and their typical power unit was one of the four-cylinder engines from the film. It’s a sidevalve design with a three-bearing crank, and it lacks innovations such as bore liners. The metallurgy and lubrication in these engines was not to the same standard as an engine of today, so a prewar Morris owner would not have expected to see the same longevity you’d expect from your daily.
Continue reading “Retrotechtacular: Constructing A Car Engine”
