Thanks to the various measurement systems in use, we aren’t sure if Volvo has created an electric truck that carries 74 metric tons, 74 short tons, or 74 long tons, but either way, that’s a lot of cargo for an electric truck. After all, that’s somewhere between 148,000 and 163,000 pounds (or 67,000 kg to 74,000 kg). That’s about three times what a typical 18-wheeler with a flatbed carries in the US. In fact, on a U.S. road, trucks typically have to weigh less than 80,000 pounds, including the truck to be legal.
Well, the monster electric Volvo has two trailers, so it is more fair to compare it to turnpike doubles, which typically carry about 148,000 pounds of cargo. The truck operates 12 hours a day and charges when the driver takes a break. At the depot, charging is from two 180 kW chargers that use green electricity, according to the company. The truck has been running for a few months, although we haven’t heard more about how successful or unsuccessful it might be.
Old diesel engines from various car manufacturers like Mercedes and Volkswagen are highly prized even in modern times. Not only were these engines incredibly reliable and mechanically simple, but they can easily be modified to run on a wide variety of fuels. It’s common to see old Volkswagen Jettas or Mercedes 300Ds running on used vegetable oil or any other free flammable liquid that might otherwise end up in the garbage. [Gijs Schalkx] has an diesel Volvo 240 wagon, and rather than compete with all the other diesel owners looking for cooking oil, he modified this one to run on plastic waste instead. (Google Translate from Dutch)
While our Dutch language skills aren’t the best, what we gather about this project is that it uses standard solid plastic waste for fuel, but an intermediate step of cooking the plastic into a liquid is first needed. The apparatus on the roof is actually a plastic refinery which uses a small wood fire to break the plastic molecules into usable hydrocarbons, which are then sent to the engine for burning. The car is street legal and seems to operate like any other diesel of this vintage, although the fuel delivery system may not be able to provide it enough to get it going at very high speeds.
While it is possible to use wood to produce wood gas for fuel in an internal combustion engine like this wood gas-powered lawnmower, the hydrocarbon strings in plastic are essentially stabilized hydrocarbons from refining oil and have potentially much more available energy. Releasing this energy is generally difficult enough that used plastic is simply landfilled. [Gijs Schalkx] has made plenty of alternative fuel vehicles, too, like this moped that used locally-harvested swamp gas to ride around town.
With cars being essentially CAN buses on wheels, it’s no wonder that there’s a lot of juicy information about the car’s status zipping about on these buses. The main question is usually how to get access to this information, both in terms of wiring into the relevant CAN bus, and decoding the used (proprietary) protocol. Fortunately for [Alex], decoding the Volvo VIDA protocol used with his Volvo C30 was relatively straightforward, enabling the creation of a custom gauge that displays information like boost pressure and coolant temperature.
The physical interfacing is accomplished via the car’s OBD port, which conveniently provides access to the car’s two (high-speed and low-speed) CAN buses. Hardware of choice is an M2 UTH (Under the Hood) board, sporting a SAM3X Cortex-M3-based MCU, designed for permanent automotive installations. On [Alex]’s GitHub project page it is explained how the protocol works, and which bytes to look for when replicating the project.
Rounding off the project is a round LCD display from 4D Systems that cycles through the status update screens. As a bonus, the dashboard illumination level is also read out in real-time, so the brightness of the display is adjusted to fit this level. All in all a well-rounded project, with interesting prospects for a more permanent integration of the gauge into the dashboard proper.
Given the age of the display, you probably won’t be surprised to hear that it uses composite video. Not exactly high resolution, but in the demonstration after the break, we have to admit it looks more than up to the task. [Luuk] is running Android Auto on the Raspberry Pi 3 through the openauto project, which gives him a nice big display and access to all the navigation and media applications you’d expect. The display doesn’t support touch, but thanks to an ESP32 plugged into the CAN bus, he’s able to control the software by reading the buttons built into the Volvo’s steering wheel.
To actually raise and lower the display, [Luuk] found you just need to fire a few bytes down the 1,200 baud serial bus that’s built into the display’s wiring harness. The ESP32 handles this duty as well, at least partly because it’s already plugged into the CAN bus and can tell when the vehicle is in reverse. This lets it bring up the screen to show the video feed from the newly installed backup camera in the event that the Pi hadn’t already asked to raise the display. Incidentally plugging in the phone normally triggers the system to wake up and raise the screen, and disconnecting it will command the screen to lower back into the stowed position.
The attentive reader or Volvo aficionado may be wondering how [Luuk] got the audio working. Since his car’s sound system doesn’t feature an auxiliary input, he’s using an Arduino to spoof the existence of a CD changer, which allows him to inject an audio signal into one of the pins on the back of the radio. Eventually he wants to move this task over to the ESP32, but he says a big change like that will have to wait until warmer weather.
The amplifiers are from a Volvo 760 made in 1984. There’s one rated at 40 watts per channel, and a smaller device rated at 25 watts per channel – likely to drive the front and rear speakers from separate amps. The amplifiers take 12 volts nominally, as one would expect. After some initial testing with a car battery and unsticking old relays, things began to crackle into life.
With the hardware now functioning, it was simply a case of bolting the amplifiers into a frame, hooking them up to a converted ATX power supply, and wiring up some connectors for speakers and audio input. With a few bits and pieces invested, [Nikita] now has a good quality amplifier to run audio in the workshop.
Old cars are great. For the nostalgia-obsessed like myself, getting into an old car is like sitting in a living, breathing representation of another time. They also happen to come with their fair share of problems. As the owner of two cars which are nearing their 30th birthdays, you start to face issues that you’d never encounter on a younger automobile. The worst offender of all is plastics. Whether in the interior or in the engine bay, after many years of exposure to the elements, parts become brittle and will crack, snap and shatter at the slightest provocation.
You also get stuck bolts. This was the initial cause of frustration with my Volvo 740 Turbo on a cold Sunday afternoon in May. As I tried in vain to free the fuel rail from its fittings, I tossed a spanner in frustration and I gave up any hope of completing, or indeed, starting the job that day. As I went to move the car back into the driveway, I quickly noticed a new problem. The accelerator was doing approximately nothing. Popping the hood, found the problem and shook my head in resignation. A Volvo 740 Turbo is fitted with a ball-jointed linkage which connects the accelerator cable to the throttle body itself. In my angst, the flying spanner had hit the throttle body and snapped the linkage’s plastic clips. It was at this point that I stormed off, cursing the car that has given me so much trouble over the past year.
Old cars are great. They represent a different time, reflecting the state of society at the point of their design and manufacture, and can charm and delight while also providing useful transport. Except, well… old cars are great, except when they’re not.
With my Volvo 740 hitting its thirtieth birthday and cresting over 200,000 miles, to say its a little worse for wear is an understatement. The turbo dadwagon has suffered transmission issues, and cold starting woes… but most frustrating is the sudden spike in fuel use. After some work, my humble daily driver had slid from using an acceptable 21 miles per gallon, to getting just 15. Add on the fact that the turbocharged engine demands premium fuel, and you can understand my consternation.
Now that I was haemorrhaging cash on a gargantuan weekly fuel bill, I had plenty of motivation to track down the problem. Busy, and eager for a quick solution, I deferred to a mechanic recommended as the local expert in all things Volvo. Sadly, the results were inconclusive — initial appearances were that all the engine’s electronic controls were functioning to specifications, and I was told that it was “probably a bad batch of fuel”.
Unfortunately, several expensive tanks later, sourced from all over town, revealed that the problem was in fact real. With a supposedly reliable report that the fuel mixture was correct, thus ruling out culprits like the oxygen sensor, I began to wonder, was I simply pouring fuel out the tank?