If you didn’t know, there’s a pecking order in the R/C world. There are the toy grade cars which you can find at your local big box store, and the hobby grade cars, which grace the shelves of the local hobby shop. Toy cars often come with great looking shells – Corvettes, Lamborghinis, Porsches, or even Ferraris. It often seems like the manufacturer spent all their money licensing and molding the shell though because the mechanics and electronics leave a lot to be desired. You could pull the body off and put it on a hobby grade R/C car, but that could get expensive. It also can be tricky to find a car with exactly the right width and wheelbase.
[HobbyPartz] had just this problem with a great looking Ferrari Enzo model that you can see in the video below the break. As expected, the pretty shell hid some really cheap electronics underneath. This is easily fixed by pulling and tossing everything electronic. The steering system was non-proportional — only full left or right turns. He removed the existing steering hardware and hot glued in a standard R/C servo. Once the servo is in position, it’s easy to connect the linkages to the wheels themselves.
Smart Christmas trees may soon come to mean something more than a fashionably decorated tree. Forging ahead with this new definition, [Ayan Pahwa], with help from [Akshay Kumar], [Anshul Katta], and [Abhishek Maurya] turned their office’s Christmas Tree into an IoT device you can watch live!
As an IoT device, the tree relies on the ever-popular ESP8266 NodeMCU — activated and controlled by Alexa, as well as from a web page. The LEDs for the tree — and the offline-only tree-topper controlled by an Arduino Pro Mini — are the similarly popular Neopixels.
On the front of a building in New York City, above a branch of the ubiquitous Starbucks coffee chain, there is a clock. It is no ordinary clock, the 200 Water Street clock is an art installation created by the artist [Rudolph de Harak], and consists of 72 lighted numbers which are illuminated in sequence to show hours, minutes, and seconds. It is a landmark of sufficient fame that [Jason Ben Nathan] and [Eldar Slobodyan], Cornell University students of [Bruce Land], decided to make their own tribute to it as their course project.
It’s a fairly straightforward build, thanks to the use of Adafruit Dotstar multicolour LED strips which are populated with APA102 pixels. Behind the scenes is a PIC32 microcontroller, and the time information comes from an off-the-shelf 60kHz WWVB time signal receiver. There is also a temperature sensor, for a handy second function.
The front panel is a piece of ply with the required numbers nicely laser-cut. All the schematics and code are available, should you fancy your hand at building your own version of the clock.
If you are curious about the real-life clock here’s an image. But you get a much more interesting perspective if you stand in front of it. If you just can’t go there, get an approximation through the wonders of Google Street View.
A hackspace discussion of voltage regulators within our earshot touched on the famous μA723, then moved on to its competitors. Kits-of-parts for linear regulators were ten-a-penny in the 1970s, it seems. A rambling tale ensued, involving a Lambda power supply with a blown-up chip, and ended up with a Google search for the unit in question. What it turned up was a hack from 2014 that somehow Hackaday missed at the time, the replication by [Eric Schlaepfer] of an out-of-production regulator chip using surface-mount semiconductors when his Lambda PSU expired.
Lambda were one of those annoying electronics companies with a habit of applying their own part numbers to commonly available chips in an effort to preserve their spares sales. Thus the FBT-031 in this Lambda PSU was in fact a Motorola MC1466, a dirt-cheap common part in the 1970s. Unfortunately though unlike the 723 the MC1466 has long passed out of production, and is rarer than the proverbial hen’s tooth.
Happily, these chips from the early 1970s were often surprisingly simple inside. The MC1466 schematic can be found on its data sheet, and is straightforward enough to replicate with surface-mount discrete components. He thus created a PCB that replicated the original pin layout even though it overlapped the original footprint. A few parts were slightly unusual, dual transistor arrays and a matched triple diode, but the result proved to be a perfect replacement for a real MC1466. Of course a project like this is almost too simple for [Eric], who went on to build the incredible Monster 6502.
To exclude musical instruments in the overflowing library of possibility that 3D printing enables would be a disservice to makers and musicians everywhere. For the minds over at [Makefast Workshop], an experimental idea took shape: a single stringed harp.
The TuneFast Harp needed enough notes for a full octave, robust enough to handle the tension of the string, a single tuning mechanism and small enough to print. But how to produce multiple notes on a harp out of only one string? V-grooved bearings to the rescue! The string zig-zags around the bearings acting as endpoints that rotate as its tuned, while the rigid PLA printing filament resists deforming under tension.
After a bit of math and numerous iterations — ranging from complete reconfigurations of part placements to versions using sliding pick mechanisms using magnets! — a melodic result!
There are a lot of cool ways to wrap a case around your custom PC build. But the off-the-shelf stuff doesn’t really set your machine apart from the herd, no matter how many RGB LEDs you put inside. If you really want to stand out, think out of the box, and build your PC into the case of an old logic analyzer.
Looking for a little retro cool factor, [Bob Alexander] turned to the world’s boneyard, eBay, and rounded up a dead H-P 1653 logic analyzer. State of the art in 1989 but not worth repairing by [Bob]’s lights, so he proceeded to remove the original 10″ CRT to make room for an alternate display. After a bit of experimentation, he settled on an LCD panel mounted behind a sheet of acrylic that he thermoformed to the shape of the CRT face. All the original guts were removed to make way for the motherboard and power supply, and a custom PCB to interface the original keypad and rotary encoder into the PC. The old buttons now launch various programs and the encoder acts as the PC volume control. The floppy drive made way for a USB hub, the BNC connectors became power and reset buttons, and a photo taken through the CRT bezel before the electronics were removed provides a window into the soul of the original instrument. It’s a really nice build, and totally unique.
We have seen a few of these types of devices in the past, and they almost always use ultrasonic sensors to gauge distance. Not so with this ETA; it uses six VL53L0X time-of-flight (ToF) sensors mounted at slightly different angles from each other, which provides a wide sensing map. It is capable of detecting objects in a one-meter-wide swath at a range of one meter from the sensors.
The device consists of two parts, a wayfinding wand and a feedback module. The six ToF sensors are strapped across the end of a flashlight body and wired to an Arduino Mini inside the body. The Mini receives the sensor data over UART and sends it to the requisite PIC32, which is attached to a sleeve on the user’s forearm. The PIC decodes these UART signals into PWM and lights up six corresponding vibrating disc motors that dangle from the sleeve and form a sensory cuff bracelet around the upper forearm.
We like the use of ToF over ultrasonic for wayfinding. Whether ToF is faster or not, the footprint is much smaller, so its more practical for discreet assistive wearables. Plus, you know, lasers. You can see how well it works in the demo video after the break.