Fail of the Week: Pinewood Derby Cheat Fails Two Ways

Would you use your tech prowess to cheat at the Pinewood Derby? When your kid brings home that minimalist kit and expects you to help engineer a car that can beat all the others in the gravity-powered race, the temptation is there. But luckily, there are some events that don’t include the kiddies and the need for parents to assume the proper moral posture. When the whole point of the Pinewood Derby is to cheat, then you pull out all the stops, and you might try building an electrodynamic suspension hoverboard car.

Fortunately for [ch00ftech], the team-building Derby sponsored by his employer is a little looser with the rules than the usual event. Loose enough perhaps to try a magnetically levitating car. The aluminum track provided a perfect surface to leverage Lenz’s Law. [ch00ftech] tried different arrangements of coils and drivers in an attempt to at least reduce the friction between car and track, if not outright levitate it. Sadly, time ran out and physics had others ideas, so [ch00ftech], intent on cheating by any means, tried spoofing the track timing system with a ridiculous front bumper of IR LEDs. But even that didn’t work in the end, and poor [ch00f]’s car wound up in sixth place.

So what could [ch00ftech] had done better? Was he on the right course with levitation? Or was spoofing the sensors likely to have worked with better optics? Or should he have resorted to jet propulsion or a propeller drive? How would you cheat at the Pinewood Derby?


2013-09-05-Hackaday-Fail-tips-tileFail of the Week is a Hackaday column which celebrates failure as a learning tool. Help keep the fun rolling by writing about your own failures and sending us a link to the story — or sending in links to fail write ups you find in your Internet travels.

Quick Arduino Hack Lets Tach-less Car Display Shift Points

A tachometer used to be an accessory added to the dash of only the sportiest of cars, but now they’re pretty much standard equipment on everything from sleek coupes to the family truckster. If your daily driver was born without a tach, fear not – a simple Arduino tachometer is well within your reach.

The tach-less vehicle in question is [deepsyx]’s Opel Astra, which from the video below seems to have the pep and manual transmission that would make a tach especially useful. Eschewing the traditional analog meter display or even a digital readout, [deepsyx] opted to indicate shift points with four LEDs mounted to a scrap of old credit card. The first LED lights at 4000 RPM, with subsequent LEDs coming on at each 500 RPM increase beyond that. At 5800 RPM, all the LEDs blink as a redline warning.  [Deepsyx] even provides a serial output of the smoothed RPM value, so logging of RPM data is a possible future enhancement.

The project is sensing engine speed using the coil trigger signal – a signal sent from the Engine Control Unit (ECU) which tells one of the ignition coilpacks to fire. The high voltage signal from the coilpack passes on to the spark plug, which ignites the air-fuel mixture in that cylinder. This is a good way to determine engine RPM without mechanical modifications to the car. Just make sure you modify the code for the correct number of cylinders in your vehicle.

Simple, cheap, effective – even if it is more of a shift point indicator than true tachometer, it gets the job done. But if you’re looking for a more traditional display and have a more recent vintage car, this sweeping LED tachometer might suit you more.

Continue reading “Quick Arduino Hack Lets Tach-less Car Display Shift Points”

3D Printed R/C Lifeboat

Radio control boats usually bring up thoughts of racing catamarans, or scale sailing yachts. This build takes things in a slightly different direction. A radio controlled lifeboat with a built-in First Person View (FPV) transmitter. [Peter Sripol] used to be one of the awesome folks over at Flite Test. Now he’s gone solo, and has been cranking out some great builds on his YouTube channel. His latest build is a lifeboat loosely based on the totally enclosed lifeboats used on oil tankers and other seafaring vessels.

[Peter] designed the boat in 3D modeling software and printed it on his Lulzbot Taz 6. The files are available on Thingiverse if you want to print your own. The lower hull was printed in two pieces then epoxied together. Peter’s musical build montage goes by fast, proving that he’s just as good editing video as he is scratch-building R/C craft. Along the way he shows us everything from wiring up speed controls to cutting and soldering up a rudder. The final touch on this boat is a micro FPV camera and radio transmitter. As long as the boat is in range, it can be piloted through video goggles.

[Peter’s] boat is destined to be tested on an upcoming trip to Hawaii, so keep an eye on his channel to see how it fares in the monster waves!

A Next-Level Home-Built Flight Simulator

Every hobby needs to have a few people who take it just a little too far. In particular, the aviation hobbies – Radio control flying, FPV multicopter racing, and the like – seem to inspire more than their fair share of hard-core builds. In witness whereof we present this over-the-top home-brew flight simulator.

His wife and friends think he’s crazy, and we agree. But [XPilotSimPro] is that special kind of crazy that it takes to advance the state of the art, and we applaud him for that. A long-time fan of flight simulator games, he was lucky enough to log some time in a real 737 simulator. That seems to be where he caught the DIY bug. The video after the break is a whirlwind tour of the main part of his build, which does not seek to faithfully reproduce any particular cockpit as much as create a plausibly awesome one. Built on a PVC pipe frame with plywood panels, the cockpit is bristling with LCD panels, flight instruments, and bays of avionics that look like they came out of a cockpit. The simulator sits facing a wall with an overhead LCD projector providing views of the outside world. An overhead panel sporting yet more LCD panels and instruments was a recent addition. The whole thing is powered by a hefty looking gaming rig running X-Plane, allowing [XPilotSimPro] to take on any aviation challenge, including landing an Embraer 109 on the deck of the USS Nimitz Aircraft Carrier.

What could be next for [XPilotSimPro]’s simulator? How about adding a little motion control with pneumatics? Or better still, how about using a real 737 cockpit as a simulator?

Continue reading “A Next-Level Home-Built Flight Simulator”

Automate the Freight: Robotic Deliveries Are on the Way

Seems like all the buzz about autonomous vehicles these days centers around self-driving cars. Hands-free transportation certainly has its appeal – being able to whistle up a ride with a smartphone app and converting commute time to Netflix binge time is an alluring idea. But is autonomous personal transportation really the killer app that everyone seems to think it is? Wouldn’t we get more bang for the buck by automating something a little more mundane and a lot more important? What about automating the shipping of freight?

Look around the next time you’re not being driven to work by a robot and you’re sure to notice a heck of a lot of trucks on the road. From small panel trucks making local deliveries to long-haul tractor trailers working cross-country routes, the roads are lousy with trucks. And behind the wheel of each truck is a human driver (or two, in the case of team-driven long-haul rigs). The drivers are the weak point in this system, and the big reason I think self-driving trucks will be commonplace long before we see massive market penetration of self-driving cars.

Continue reading “Automate the Freight: Robotic Deliveries Are on the Way”

Faulty Parking Meter Tracking System? RFID To The Rescue!

How often do you see problems that need fixing? How often do you design your own solutions to them — even if they won’t be implemented at scale? Seeing that many of the municipal parking lots in his native Sri Lanka use a paper ticketing system which is prone to failure, [Shazin Sadakath] whipped up his own solution: an efficient RFID tag logging system.

Digging out an HZ-1050 RFID reader — as well an RFID card and two tags — [Sadakath] set to work connecting it to his Raspberry Pi and cooking up a batch of code and a dashboard to work with. A Python script — using a PiGPIO library — reads the Wiegand Format RFID number, storing it in an SQLite3 database. A Bootstrap, Javascript, and JQuery trifecta make up the dashboard that pulls the RFID info from said server and organizes it into a functional format.

Continue reading “Faulty Parking Meter Tracking System? RFID To The Rescue!”

EM Drive Paper Published By Eagleworks Team

There are one or two perennial scientific stories that sound just too good to be true, but if they delivered on their promise would represent a huge breakthrough and instantly obsolete entire fields. One example is so-called “cold fusion”, the idea that nuclear fusion could be sustained with a net energy release at room temperature rather than super-high temperature akin to that of the sun. We all wish it could work, but so far it has obstinately refused. As a TV actor portraying a space engineer of the future once said, one “cannae change the Laws of Physics“.
Continue reading “EM Drive Paper Published By Eagleworks Team”