Electric Truck Sets Racing Record

The 24 Hours of Le Mans races is an extremely prestigious endurance motorsport event which attracts the best cars and drivers from around the world. It’s one of the longest-running races too, taking place once a year since 1923 (with a few obvious understandable gaps). But, like most motorsports, it’s financially out of reach for most people. One of the more popular attempts to bring racing to the masses has been the 24 Hours of Lemons races, which have price limits on vehicles to keep the barrier to entry low, and an EV truck recently entered one of these races with some interesting results.

The group behind this vehicle is called Team Arcblast, who retrofitted an old Datsun pickup truck to the extreme to enter this race. The modestly sized electric motor is installed in between the cab and the bed for easy access to the driveshaft, with the engine bay repurposed for all of the cooling and radiators needed for endurance racing like this. They’ve also equipped the truck with plenty of efficiency-increasing spoilers and other aerodynamic parts, and rebuilt the cab with not only the required roll cage and other safety equipment, but a modified driving position with steering and other components from various Miatas.

The most impressive part of this build, however, is the battery. The team invented a method of swapping out batteries quickly to avoid having to fast charge the car in the pit area. The system lets a battery slide in to the middle of the truck above the motor and quickly connect to the electrical system allowing for very quick pit stops and the ability to charge other batteries while the race goes on. All of these modifications together allowed the team to break the EV record for a Lemons race.

For a Lemons race, though, even this truck stretches the original spirit that these races were started, however impressive the build. We published a primer to these types of races a while back which includes much more affordable internal combustion options.

Thanks to [JohnU] for the tip!

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Elongating A BMX For Drag Racing

BMX bikes are a unique frame geometry, essentially forgoing all travel efficiency for maneuverability and sturdiness. For how much abuse these bikes are designed to take, these are all good tradeoffs. But it turns out that these bikes also have an exceptionally low center of gravity, which could make them useful for drag racing, provided they’re given a suitably large electric motor and a few minor frame modifications.

The project began as a fun weekend project for friends [Sam Barker] and [Tom Stanton]. They had a 20″ BMX wheel with a massive integrated hub motor that seemed to be begging to be put onto a BMX bike that they had on hand. After hooking up a 72V, 20Ah battery to it they were quickly zipping around the driveway, but the short wheelbase on the bike was bottlenecking its maximum performace because the bike would wheelie under high throttle. To solve that, they broke out the welder and extended frame, which kept the wheelies to a minimum and allowed them to take it out and drag race.

Another benefit to the extended frame is that the bike has room to store its battery now as well; before the frame extension it was strapped to the side of the frame under the rider in a non-ergonomic fashion. The duo also had to figure out a braking solution since the BMX didn’t come with its own brakes, but a loaner caliper from a penny farthing was found for some basic stopping abilities. We might assume this bike is not street legal on many public roads, but not every ebike operates in the same legal jurisdictions you might be the most familiar with.

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A Heavily Modified Rivian Attempts The Cannonball Run

There are few things more American than driving a car really fast in a straight line. Occasionally, the cars will make a few left turns, but otherwise, this is the pinnacle of American motorsport. And there’s no longer, straighter line than that from New York to Los Angeles, a time trial of sorts called the Cannonball Run, where drivers compete (in an extra-legal fashion) to see who can drive the fastest between these two cities. Generally, the cars are heavily modified with huge fuel tanks and a large amount of electronics to alert the drivers to the presence of law enforcement, but until now, no one has tried this race with an EV specifically modified for this task.

The vehicle used for this trial was a Rivian electric truck, chosen for a number of reasons. Primarily, [Ryan], the project’s mastermind, needed something that could hold a significant amount of extra batteries. The truck also runs software that makes it much more accepting of and capable of using an extra battery pack than other models. The extra batteries are also from Rivians that were scrapped after crash tests. The team disassembled two of these packs to cobble together a custom pack that fits in the bed of the truck (with the tonneau closed), which more than doubles the energy-carrying capacity of the truck.

Of course, for a time trial like this, an EV’s main weakness is going to come from charging times. [Ryan] and his team figured out a way to charge the truck’s main battery at one charging stall while charging the battery in the bed at a second stall, which combines for about a half megawatt of power consumption when it’s all working properly and minimizes charging time while maximizing energy intake. The other major factor for fast charging the battery in the bed was cooling, and rather than try to tie this system in with the truck’s, the team realized that using an ice water bath during the charge cycle would work well enough as long as there was a lead support vehicle ready to go at each charging stop with bags of ice on hand.

Although the weather and a few issues with the double-charging system stopped the team from completing this run, they hope to make a second attempt and finish it very soon. They should be able to smash the EV record, currently held by an unmodified Porsche, thanks to these modifications. In the meantime, though, there are plenty of other uses for EV batteries from wrecked vehicles that go beyond simple transportation.

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Vintage Game Rides Again Thanks To Modern Tech

You have to admire the lengths designers went to back in the day to create engaging games and toys. One particularly clever game of this type was called GEE-WIZ, a horse racing game from the 1920s that seems like it might have been right at home at a bar or pub, and that caught [Michael Gardi]’s imagination enough that he built a modern version of the game.

GEE-WIZ imitates a horse race with an extremely clever mechanism powered by a flywheel on a square shaft. Play is started by pulling a ripcord, which spins up the flywheel to shoot steel balls up six tracks in a gently sloped playing field. The balls hit tin horses riding in each track, pushing them ever further up the track until they trip a flag to indicate the winner. We can practically hear the cheers.

As with many of his other retro-reimaginings, [Mike]’s 21st-century version of GEE-WIZ focuses on capturing the look and feel of the original as accurately as possible. To that end, he put a lot of work into the 3D prints that form the playing field, as well as labels that adorned the original. But the game wouldn’t be much good without the drive mechanism, so [Mike] had to put some work into reverse-engineering the flywheel. He had that machined out of stainless steel and mounted it to the base with some chunky printed bearing blocks. You can see the final product in the brief video below.

[Mike] says that vintage toy recreations aren’t exactly his usual fare, but some might argue that the Sol-20 and Minivac 601 very much count as toys. Either way, we really like the simplicity of GEE-WIZ and the quality of [Mike]’s reproduction.

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Ordering Pizza While Racing

As [Matt Stele] prepared to bike a local 300-mile (~480km) race in addition to training, he had to prepare for food. A full day of riding was ahead on gravel trails, and one of the best options for him was Casey’s General Store pizza. However, as it was a race, other riders were much faster than him. So, all the hot slices were gone when he arrived. With the help of a serverless GPS tracker, some cloud lambdas, and some good old-fashioned web scraping, [Matt] had a system that could order him a fresh pizza at the precise moment he needed. Continue reading “Ordering Pizza While Racing”

Race RC Cars From Anywhere On Earth

Racing games have come a long way over the years. From basic 2D sprite-based titles, they’ve evolved to incorporate advanced engines with highly realistic simulated physics that can even be used to help develop real-world automobiles. For [Surrogate.tv], that still wasn’t quite good enough, so they decided to create something more rooted in reality.

The game is played in a web browser. Players are assigned a car and view the action from a top-down camera.

Their project resulted in a racing game based on controlling real RC cars over the internet, in live races against other human opponents. Starting with a series of Siku 1:43 scale RC cars, the team had to overcome a series of engineering challenges to make this a reality. For one, the original electronics had to be gutted as the team had issues when running many cars at the same time.

Instead, the cars were fitted with ESP8266s running custom firmware. An overhead GoPro is used with special low-latency streaming software to allow players to guide their car to victory. A computer vision system is used for lap timing, and there’s even automatic charging stations to help keep the cars juiced up for hours of play.

The game is free to play online, with the races currently operating on a regular schedule. We look forward to trying our hand at a race or three, and will be interested to see how the latency holds up from various parts of the world.

We’ve seen other remote RC builds before; usually featuring the power of the Raspberry Pi. We’ve also covered useful techniques for low latency video for real-time applications. Video after the break.

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Row Your Bike To China

If you’re a fan of endurance racing motor vehicles, there’s one that puts the 24 Hours of Le Mans, the Dakar Rally, and the Baja 1000 to shame, and the race doesn’t even involve cars. Indeed, the vehicles used for this massive trek from France to China are electric bicycles, powered only by solar panels. This is the epic Sun Trip endurance race, and one of its competitors built a unique tandem bike that is powered both by pedaling, rowing, and the solar panels.

The tandem bike is interesting on its own since the atypical design uses a back-to-back layout which means one person is facing backward, but the storage space is dramatically increased over the normal forward-facing layout. The person in the rear doesn’t pedal, though. [Justin_le] built an upper-body-powered rowing station for that spot so that the person riding back there can rest their legs but still help propel the vehicle. Of course, there’s also a solar panel roof so the two riders can pedal and row in the shade, which includes MPPT and solar tracking which drives a small electric motor on board as well.

This race started in June but is still going on. There’s a live GPS feed so you can keep up with the teams, and if you get really inspired you can go ahead and sign up for the 2019 race as well. This particular bike was also featured on Radio Canada as well if you’d like to learn more about it.

Thanks to [Arthur] for the tip!