Who would have thought you could make a game out of an optical bench? [Chris Mitchell] did, and while we were skeptical at first, his laser Light Bender game has some potential. Just watch your eyes.
The premise is simple: direct the beam of a colored laser to the correct target before time runs out. [Chris] used laser-cut acrylic for his playfield, which has nine square cutouts arranged in a grid. Red, green, and blue laser pointers line the bottom of the grid, with photosensors and RGB LEDs lining the grid on the other three sides. Play starts with a random LED lighting up in one of the three colors, acting as a target. The corresponding color laser comes on, and the player has to insert mirrors or pass-through blocks in the grid to create a path to the target. The faster you hit the CdS cell, the higher your score. It’s simple, but it looks really engaging. We can imagine all sorts of upgrades, like lighting up two different targets at once, or adding a beamsplitter block to hit two targets with the same color. Filters and polarizers could add to the optical fun too.
We like builds that are just for fun, especially when they’re well-crafted and have a slight air of danger. The balloon-busting killbots project we featured recently comes to mind.
Continue reading “Lasers, Mirrors, And Sensors Combine In An Optical Bench Game”
Those of us who aren’t familiar with woodworking might not expect that this curved wood and acrylic LED lamp by [Marija] isn’t the product of fancy carving, just some thoughtful design and assembly work. The base is a few inches of concrete in a plastic bowl, then sanded and given a clear coat. The wood is four layers of beech hardwood cut on an inverted jigsaw with the middle two layers having an extra recess for two LED strips. After the rough-cut layers were glued together, the imperfections were rasped and sanded out. Since the layers of wood give a consistent width to the recess for the LEDs, it was easy to cut a long strip of acrylic that would match. Saw cutting acrylic can be dicey because it can crack or melt, but a table saw with a crosscut blade did the trick. Forming the acrylic to match the curves of the wood was a matter of gentle heating and easing the softened acrylic into place bit by bit.
Giving the clear acrylic a frosted finish was done with a few coats of satin finish clear coat from a spray can, which is a technique we haven’t really seen before. Handy, because it provides a smooth and unbroken coating along the entire length of the acrylic. This worked well and is a clever idea, but [Marija] could still see the LEDs and wires inside the lamp, so she covered them with some white tape. A video of the entire process is embedded below.
Continue reading “Curved Wood LED Lamp Needs No Fancy Tools”
[smash_hand] had a clear goal: a big, featureless, white plastic disk with RGB LEDs concealed around its edge. So what is it? A big ornament that could glow any color or trippy mixture of colors one desires. It’s an object whose sole purpose is to be a frame for soft, glowing light patterns to admire. The disk can be controlled with a simple smartphone app that communicates over Bluetooth, allowing anyone (or in theory anything) to play with the display.
The disk is made from 1/4″ clear plastic, which [smash_hand] describes as plexiglass, but might be acrylic or polycarbonate. [smash_hands] describes some trial and error in the process of cutting the circle; it was saw-cut with some 3-in-1 oil as cutting fluid first, then the final shape cut with a bandsaw.
The saw left the edge very rough, so it was polished with glass polishing compound. This restores the optical properties required for the edge-lighting technique. The back of the disc was sanded then painted white, and the RGB LEDs spaced evenly around the edge, pointing inwards.
The physical build is almost always the difficult part in a project like this — achieving good diffusion of LEDs is a topic we talk about often. [smash_hands] did an impressive job and there are never any “hot spots” where an LED sticks out to your eye. With this taken care of, the electronics came together with much less effort. An Arduino with an HC-05 Bluetooth adapter took care of driving the LEDs and wireless communications, respectively. A wooden frame later, and the whole thing is ready to go.
[smash_hands] provides details like a wiring diagram as well as the smartphone app for anyone who is interested. There’s the Arduino program as well, but interestingly it’s only available in assembly or as a raw .hex file. A video of the disk in action is embedded below.
Continue reading “RGB Disk Goes Interactive With Bluetooth; Shows Impressive Plastic Work”
It’s pretty easy to train a dog to do things for treats. They’re eager to please. But a cat? Most cats have better things to do than learn tricks no matter how many treats are involved. But if you make an autonomous game out of learning a trick, they just might go for it.
That’s the idea behind Touchy Fishy, a pinball machine for cats. It’s the newest iteration of treat-dispensing machines that [Kim] made for his cat, MIDI. The previous version was shaped like a dog’s head with a joystick for a nose. MIDI was so adept at pulling the joystick toward herself that [Kim] decided to try a new design using a lever.
Humans like challenges, too, and [Kim] wanted to make something purely mechanical this time around. The final product is mostly springs and laser-cut acrylic. MIDI pulls the spring-loaded lever downward, launching a pinball upward in an arc. At the top of its trajectory is a spinner enclosed in a circle. When the pinball hits the spinner, it sweeps a treat toward an opening, and the treat falls down where MIDI can eat it. The best part? The spinner also returns the captive pinball to its starting point, so MIDI can play until [Kim] gets tired of dropping treats into the hole. Watch MIDI claw her way to the high score after the break.
Most of the cat-related projects we’ve seen were built to keep hungry cats from sitting on their owner’s chests at 3AM, demanding to be fed. Here’s one that goes a step further by putting the cat to work collecting wiffle balls which it uses to pay for small amounts of kibble.
Continue reading “Cat Plays The Silver Ball For Treats”
Prolific maker [Sean Hodgins] has taken the wraps off of his latest one-day build, and as usual, it takes the kind of spare parts most people reading Hackaday will have in their parts bins and turns it into something fun and useful. This time around, he takes a bunch of spare arcade-style buttons he had from a previous project and combines them with an Adafruit Trinket (SAMD21 flavor) to make a USB input device for his computer.
[Sean] uses 1/4 inch acrylic to make the case, though he does mention that it could just as easily be 3D printed. But using the acrylic is easy and gives a nice glossy look to the final hardware. With a saw and a drill press you can make some very professional cases out of acrylic, which goes to show that you don’t necessarily need to have a high end 3D printer to create great looking enclosures.
As explained in the video, the Adafruit Trinket is not strictly necessary for this build, it’s just what [Sean] had lying around. Any microcontroller that can present itself to the operating system as a USB Human Interface Device (HID) will work fine for a project like this.
Software wise, a modified Arduino demo program is used to equate the states of the digital pins to pre-defined key combinations to be sent to the computer. In this simple example the key combinations are hard-coded into the Trinket’s source code, but a future enhancement could be adding a method of setting up new key combinations with a configuration tool.
We’ve covered our fair share of non-traditional USB input devices, all operating on largely the same principle. As it turns out, hackers have quite a pension for making oddball input devices.
Continue reading “Arcade Style Computer Hotkeys”
For all the hustle and bustle of the holiday season, people still find ways to make time for their passions. In the lead up to Christmas, [Edwin Mol] and a few co-workers built themselves an LED Christmas tree that adds a maker’s touch to any festive decor.
Before going too far, they cut out a cardboard mock-up of the tree. This an easy step to skip, but it can save headaches later! Once happy with the prototype, they printed off the design stencils and cut the chunks of clear acrylic using power tools — you don’t need a laser cutter to produce good stuff — and drilled dozens of holes in the plastic to mount LEDs, and run wires.
A Raspberry Pi 3 and Arduino Uno make this in league with some pretty smart Christmas trees. MAX6968 5.5V constant-current LED driver chips and MOFSETs round out the control circuit. During the build, the central LED column provided a significant challenge — how often do you build a custom jig to solder LEDs? That done, it’s time for a good ol’-fashioned assembly montage! The final product can cycle through several different lighting animations in a rainbow of colours — perfect for a festive build. Continue reading “A Clear Christmas Tree Means More Lights!”
Look around your bench and chances are pretty good that there’s a PCB or scrap of perfboard or even a breadboard sitting there, wires and LEDs sprouting off it, doing something useful and interesting. Taking it to the next level with a snazzy enclosure just seems too hard sometimes, especially if you don’t have access to a 3D printer or laser cutter. But whipping up plastic enclosures can be quick and easy with this simple acrylic bending outfit.
At its heart [Derek]’s bending rig is not much different from any of the many hot-wire foam cutters we’ve featured. A nichrome wire with a tensioning spring is stretched across a slot in a flat work surface. The slot contains an aluminum channel to reflect the heat from the wire upward and to protect the MDF bed; we wonder if perhaps an angle section set in a V-groove might not be more effective, and whether more vertical adjustment range would provide the wider heating area needed for wider radius bends. It works great as is, though, and [Derek] took the time to build a simple timer to control the heating element, for which of course he promptly built a nice looking enclosure.
We can imagine the possibilities here are endless, especially if you use colored acrylic or Lexan and add in some solvent welding. We’ve covered acrylic enclosure techniques before; here’s a post that covers the basics.
Continue reading “Simple Jig Gives Plastic Homes To Orphaned Projects”