I’m sure many of us remember building toy car race tracks as kids, racing the cars, and then arguing over which car came in first and who cheated because they let go of their car too soon. Ah, good times. [Phil] wanted to create a drag strip race track for his son to introduce him to die-cast cars. The only commercial drag strip [Phil] could find didn’t have an electronic start gate or a timer, so he created his own with the help of an Arduino, a servo, and some light dependent resistors.

The Arduino controls everything, the button input, the light sensor input, and the servo. A button press tells the Arduino to start the race by pulling the start gate down and starting the timer. When the light sensor is covered, the timer for that lane stops. The time is shown for each lane using a different colored 4-digit 7-segment LED.

There were a couple of problems that had to be solved. The servo launching the cars was pulling too much power when activated so that the IR LEDs used at the finish line would dim enough to trigger before the race had even begun! [Phil]’s article goes over these issues and his design ideas as he built the track.

It’s a simple build that should provide hours of fun for [Phil]’s son and his friends over the years and will hopefully put to rest any arguments over who won. There are lots of photos in [Phil]’s article, as well as several videos showing off how things work and at the end of the article, he includes the code he used to control everything. This would be a great surprise for any nieces and nephews coming to visit over the holidays — you might want to wait for final assembly and include them in the fun!

If you like these kind of projects, we’ve seen a similar Hot Wheels timing system, and a different kind of race track based on a turntable system.

It seems Power Wheels are like LEGO — they’re handed down from generation to generation.  [Nicolas] received his brand-new Peg-Perego Montana Power Wheels in 1997 as a Christmas present. After sitting in a barn for a decade, and even being involved in a flood, it was time to give it to his godchildren, though not without some restoration and added features. His webpages have a very good write-up, just shy of including schematics, but you’ll find an abbreviated version below.

Due to time and the flood, not only did it need a new paint job, and some plastic bits restored, but the hard plastic wheels had to be emptied of water, and the entire wiring harness needed replacing, as did some of the screws. Luckily the gearbox and motors needed only cleaning and new grease.

Whether it needed it or not, [Nicolas] wanted to add an Arduino Teensy 2.0++ as brains as he hadn’t seen anyone do that before and it also allowed him to brush up on his Arduino skills.

He first made use of the Arduino for one new feature, a speedometer with a dash mounted Nokia 5110 LCD display. To measure the speed he used an infrared diode along with an NPN transistor, two LM324 op-amps and a few other parts. He even drew up with some very nice custom graphics for the LCD display.

He’d originally planned to add a variable accelerator by having the Arduino do PWM to a custom H-bridge, and even went a fair way toward making it, but even at 100% PWM the speed was too slow. With only a bad oscilloscope at the time for debugging, he abandoned the H-bridge for relays instead.

When it came to the lighting, [Nicolas] went all out with high intensity white and blue LEDs on custom circuit boards. He also had to do an exhaustive search online for light covers, but luckily there’s quite a bit out there for Power Wheels parts, though some he took from a Civic at a junkyard. [Nicolas] is in France and reading his experience in hunting for these parts gives an interesting look into the difficulties in buying things from the US when shipping costs can easily exceed parts cost. We can see why sometimes it’s simply not an option.

Another new feature was a dash mounted radio. That was followed by a new battery charger, a quantity of fuses to rival that in many cars, a lovingly done paint job and many labels and stickers that show just what a job of passion this was. We’re sure his godchildren will love their better-than-new Power Wheels.

Mind you, Hackaday is no stranger to Power Wheels. But while [Nicolas’] is intended to be a safe one for his godchildren, we’ve seen them modified in the extreme opposite way with racing ones that do turns on two wheels only. Some races even have pit crews and involve vehicles with battery packs from Ford Fusion plugin hybrids.

[Mathieu] wrote in with his laser target practice game. It’s not the most amazing hack in the history of hackery, but it’s an excellent example of the type of simple and fun things you can do with just a little bit of microcontrollering.

First off, the gun is a broken toy gun that used to shoot something other than red collimated light beams. The Arduino knockoff inside reacts to a trigger pull and fires the laser for around 200 milliseconds. The gun also has a “gas gauge” that fills up with repeated shots and cools down over time. And therein lies the game — a simple race to ten, where each player only has a fixed number of shots over time.

The targets are simply a light sensor, scorekeeping LED display, and a buzzer that builds tension by beeping at you as the countdown timer ticks down. The bodies are made out of 3D-printed corners that connect some of [Mathieu]’s excess wooden goat-cheese lids.

All the code is up on GitHub so you can make your own with stuff that you’ve got lying around the house. The “gun” can be anything that you can embed a laser in that makes it aimable. Good clean fun!

[Markus Gritsch] and his son had a fun Sunday putting together a little toy airboat from a kit. They fired it up and it occurred to [Markus] that it was pretty lame. It went forward and sometimes sideward when a stray current influenced its trajectory, but it had no will of its own.

The boat was extracted from water before it could wander off and find itself lost forever. [Markus] did a mental inventory of his hacker bench and decided this was a quickly rectified design shortcoming. He applied a cheap knock-off arduino, equally cheap nRF24L01+ chip of dubious parentage, and their equivalent hobby servo to the problem.

Some quick coding later, assisted by prior work from other RC enthusiasts, the little boat was significantly upgraded. Now the boat could be brought back to shore using any R/C controller that supported the, “Bayang,” protocol. He wouldn’t have to face the future in which he’d have to explain to his son that the boat, like treacherous helium balloons, was just gone. Video after the break.

[JAC_101], the Director of Legal Evil Emeritus for LVL1 Hackerspace (don’t ask me, it’s their title system), was challenged to a hacking duel. It all started years ago. The person who is now president of LVL1, visited the space for the first time and brought with her a discarded Apple II controller for Lego bricks which had previously belonged to her father. Excited to test it, the space found that, unfortunately, LVL1’s Apple II wouldn’t boot. An argument ensued, probably some trash talking, and [JAC_101] left with the challenge: Could he build an Arduino interface for the Apple II Lego controller quicker than the hackerspace could fix its Apple II?”

In the end, a concentrated force by one hacker over two years overcame the collective ADHD of many. He began by opening the interface to look inside, a completely unnecessary step since he found it was already thoroughly documented. Next he forgot about the project for a year. Then he remembered it, and built an interface for an Arduino Uno to hook to the controller and wrote a library for the interface. Realizing that sending serial commands was not in line with the original friendly intention of the device, he added a graphical display to the project; which allowed the user to control the panel with touch. In the end he won the challenge and LVL1 still doesn’t have a working Apple II. We assume some gloating occurred. Some videos of it in action after the break.

Turning the classic toy Etch-A-Sketch into a CNC drawing tablet intrigues a large number of hackers. This version by [GeekMom] certainly takes the award for precision and utility. Once you build something like this, you can hardly stop writing firmware for it; [GeekMom] produced an entire Arduino library of code to allow joystick doodling, drawing web images, and a self-erasing spirograph mode. The topper is the version that runs as a clock!

The major hassle with making a CNC version of this toy is the slop in the drawing mechanism. There is a large amount of backlash when you reverse the drawing direction. If that isn’t bad enough, the backlash is different in the vertical or horizontal directions. Part of [GeekMom’s] presentation is on how to measure and correct for this backlash.

The EtchABot uses three small stepper motors. Two drive the drawing controls and the third flips the device forward to erase the previous drawing. The motors are each controlled by a ULN2003 stepper motor drivers. An Arduino Uno provides the intelligence. Optional components are a DS3231 Real Time Clock and a dual axis X-Y joystick for the clock and doodling capability. Laser cut wood creates a base for holding the Etch-A-Sketch and the electronics.

The write up and details for this project are impressive. Be sure to check out the other entries in [GeekMom’s] blog. Watch the complete spirograph video after the break.

If you are from the 1960’s or 1970’s we know you would have enjoyed furiously punching the buttons of a pin ball machine back in the day. Installation artist [Niklas Roy] recently revisited this old classic game and built Galactic Dimension – a supersized pinball machine for Phæno – an amazing science center in the German city of Wolfsburg. The science centre was planning a big exhibition featuring thirty beautiful, classic pinball machines loaned from the Pacific Pinball Museum in Alameda, California.

The game machine was built on a steep ramp and has a gigantic play field measuring 3m x 6m (10’x20′). It features Sci-Fi game elements in the play field which blend perfectly with the futuristic building where it is housed. The game elements are built from repurposed everyday items like hair dryers and fans, giving visitors the motivation to build some of their own such contraptions.

The players operate the machine via a control desk, and a giant calculator is used to display the game score. The steep ramp had an incline of almost 30° which meant that he had to use a light ball to be able to propel it around the play field. The main user controls are the two flippers, and building giant ones was a big challenge. Solenoids or coils would not cut the ice, and he settled for pneumatic cylinders – easy to control, powerful, not too loud, and the museum already had a compressed air supply readily available. But it still took him three iterations before he could get it right. The plunger, which initially propels the ball, was built from PVC pipes and a hair dryer. Each play field element was built as a separate module to make assembly and maintenance easier. All featured a 220V AC supply, a sensor (either an IR distance sensor or a light barrier) to detect the ball, and an Arduino. Actuators were built from hair dryers and portable fans. Each of them have their own sound effects too – either a hacked toy or a speaker controlled by the Arduino. After everything was built, taken apart, transported, and reassembled at the site, the Galactic Dimension worked without a glitch, and without releasing any magic smoke. To top it off, Andreas Harre, who’s been the German pinball champion for several years in a row, also played the machine when he visited Phæno – and was totally excited about it!

So if you are in that part of Germany anytime until September, do drop in and try to ring up a big score. For photos of his build log, check out the photo album. There’s also a fairly big block diagram (German) and the Arduino sketches (.zip file), if you’d like to take a stab at building an even bigger pinball machine. Check the video to see the machine in action. And if the name [Niklas] sounds familiar, it is because he loves building installations such as the Forbidden Fruit Machine, the Ball Sucking Machine, and another Ball Sucking Machine.

There are a lot of simulators out there if you want to try something out that would be otherwise impossible. Great examples are flight simulators for simulating the piloting of a fighter jet, or goat simulators for simulating the life of a goat who destroys a town. [Erland] wanted a pinball machine, but like planes and goats, found it was impractical to get a real one because it would probably upset his neighbors in his apartment. Instead, he set out to build a pinball simulator.

The cabinet is miniature-sized compared to a regular pinball machine so it can more easily fit in the apartment. It utilizes three monitors, a 24″ one in portrait mode for the main playing area, a 20″ one for the back screen, and a smaller one for the “dot matrix” style scoreboard. Once the woodwork was completed, a PC was put together to control everything and an Arduino was installed to handle the buttons and output USB commands to the PC.

Of course, we’ve featured many other pinball simulators before, but this one is no slouch when it comes to features either. It is very well crafted and the project is very well documented, and the miniature size sets it apart as well. However, if you want to go a step further with your pinball simulator, you might want to check out this augmented reality pinball system.

[Apachexmd] wanted to do something fun for his three-year-old son’s birthday party. Knowing how cool race cars are, he opted to build his own Hot Wheels drag race timer. He didn’t take the easy way out either. He put both his electronics and 3D printing skills to the test with this project.

The system has two main components. First, there’s the starting gate. The cars all have to leave the gate at the same time for a fair race, so [Apachexmd] needed a way to make this electronically controlled. His solution was to use a servo connected to a hinge. The hinge has four machine screws, one for each car. When the servo is rotated in one direction, the hinge pushes the screws out through holes in the track. This keeps the cars from moving on the downward slope. When the start button is pressed, the screws are pulled back and the cars are free to let gravity take over.

The second component is the finish line. Underneath the track are four laser diodes. These shine upwards through holes drilled into the track. Four phototransistors are mounted up above. These act as sensors to detect when the laser beam is broken by a car. It works similarly to a laser trip wire alarm system. The sensors are aimed downwards and covered in black tape to block out extra light noise.

Also above the track are eight 7-segment displays; two for each car. The system is able to keep track of the order in which the cars cross the finish line. When the race ends, it displays which place each car came in above the corresponding track. The system also keeps track of the winning car’s time in seconds and displays this on the display as well.

The system runs on an Arduino and is built almost exclusively out of custom designed 3D printed components. Since all of the components are designed to fit perfectly, the end result is a very slick race timer. Maybe next [Apachexmd] can add in a radar gun to clock top speed. Check out the video below to see it in action.

[Jon] and his brother converted an RC car into a robot that can fire airsoft pellets into the air. The little motorized vehicle was disassembled and a handheld was attached to the top. A pulling mechanism was put in place and a safety procedure was added to make sure no accidents occurred.

An Arduino was used to get the servo working, and a chassis stand was created to hold the handle. The setup was then tested at this point, and a Raspberry Pi server was configured to install a motion sensing camera that would act as the eyes for the robot. Once everything was in place, the wheels hit the ground and the vehicle was able to move around, positioning itself to aim the servos at a designated target. Footage was transmitted via the web showing what the robot was looking at.

A video of the remote-controlled counter-strike robot can be seen after the break. You could consider this your toy army. That makes this one your toy air force.