LIDAR System Isn’t Just A Rangefinder Anymore

March 24, 2020 by Bryan Cockfield 15 Comments

For any project there’s typically a trade-off between quality and cost,as higher quality parts, more features, or any number of aspects of a project can drive its price up. It seems as though [iliasam] has managed to avoid this paradigm entirely with his project. His new LIDAR system knocks it out of the park on accuracy, sampling, and quality, and somehow manages to only cost around $114 in parts.

A LIDAR system works by sending out many pulses of light in different directions, measuring the reflections of that light as it returns. LIDAR systems therefore improve with higher frequency pulses and faster control electronics for both the laser output and the receiving data. This system manages to be accurate to within a few centimeters and works up to 25 meters all while operating at 15 scans per second. The key was a high-powered laser module which can output up to 75 watts for extremely short times. More details can be found at this page (Google Translate from Russian).

Another bonus from this project is that [iliasam] has made everything available from his GitHub page including hardware specifications, so as long as you have a 3D printer this won’t take long to produce either. There’s even detailed breakdowns of how the laser driving circuitry works, and how there are safety features built in to keep anyone’s vision from accidentally getting damaged. Needless to say, this isn’t just a laser rangefinder module but if you want to see how you can repurpose those, [iliasam] can show you that as well.

Camera And Code Team Up To Make Impossible Hovering Laser Effect

March 5, 2020 by Dan Maloney 20 Comments

Right off the bat, we’ll say that this video showing a laser beam stopping in mid-air is nothing but a camera trick. But it’s the trick that’s the hack, and you’ve got to admit that it looks really cool.

It starts with the [Tom Scott] video, the first one after the break. [Tom] is great at presenting fascinating topics in a polished and engaging way, and he certainly does that here. In a darkened room, a begoggled [Tom] poses with what appears to be a slow-moving beam of light, similar to a million sci-fi movies where laser weapons always seem to disregard the laws of physics. He even manages to pull a [Kylo Ren] on the slo-mo photons with a “Force Stop” as well as a slightly awkward Matrix-style bullet-time shot. It’s entertaining stuff, and the effect is all courtesy of the rolling shutter effect. The laser beam is rapidly modulated in sync with the camera’s shutter, and with the camera turned 90 degrees, the effect is to slow down or even stop the beam.

The tricky part of the hack is the laser stuff, which is the handiwork of [Seb Lee-Delisle]. The second video below goes into detail on his end of the effect. We’ve seen [Seb]’s work before, with a giant laser Asteroids game and a trick NES laser blaster that rivals this effect.

Continue reading “Camera And Code Team Up To Make Impossible Hovering Laser Effect” →

Star Wars Themed Laser Badge: All That Is Missing Is The Pew Pew Sound Effect

February 13, 2020 by Jenny List 9 Comments

In the quest to advance the art of the electronic badge, the boundaries of what is possible to manufacture in small quantities are continually tested. Full-colour PCBs, injection moulding, custom keyboards, and other wow factor techniques have all been tried, leading to some extremely impressive creations. With all this innovation then it’s sometimes easy to forget that clever design and a really good idea can produce an exceptional badge with far more mundane materials.

The 10th InCTF cybersecurity contest held at Amrita, Kerala, India, had a Star Wars themed badge designed by Team bi0s for the event. It takes the form of a Millennium Falcon-shaped PCB, with a NodeMCU ESP8266 board mounted on it, a shift register, small OLED display, and the usual array of buttons and LEDs. The fun doesn’t stop there though, because it also packs a light-dependent resistor and a laser pointer diode that forms part of one of its games. Power for this ensemble comes courtesy of a set of AA cells on its underside.

They took a novel approach to the badge’s firmware, with a range of different firmwares for different functions instead of all functions contained in one. These could be loaded through means of a web-based OTA updater. Aside from a firmware for serial exploits there was an Asteroids game, a Conway’s Game Of Life, and for us the star of the show: a Millennium Cannon laser-tag game using that laser. With this, attendees could “shoot” others’ LDRs, with three “hits” putting their opponent’s badge out of action for a couple of minutes.

Unusually this badge is a through-hole design as a soldering teaching aid, but its aesthetics do not suffer for that. We like its design and we especially like the laser game, we look forward to whatever next Team bi0s produce in the way of badges.

This isn’t the first badge packing a laser we’ve seen, at last year’s Def Con there was a laser synth badge. No laser tag battles though.

A Laser Drawing Machine For Flashes Of Creativity

February 7, 2020 by Kristina Panos 6 Comments

Ahh, midterms. Some students blow off steam between study sessions by playing video games or just zoning out. While those kids were all distracted, [Justinwong777] and his buddy [Brett] found a bunch of scrap wood and built this laser drawing machine in their school’s makerspace. You operate it as you might an Etch-a-Sketch, except your drawings are as fleeting as sparkler art on the 4th of July, if they made Tron-colored sparklers.

Though you work it like an Etch-a-Sketch, the business end operates like a laser cutter. Inside that plywood enclosure is an Arduino Uno and a pair of motors. These motors turn a series of custom gears, which move a small mirror angled at 45° in the xy-plane. There’s a 30mW laser mounted parallel with the base, pointed at the mirror, and it reflects the beam toward a canvas panel coated with phosphorescent paint. We dig the printed ergonomic case for the joystick, which gives control of both x and y. Put on some eye protection and check it out after the break.

If you want to draw with lasers, but aren’t much of an artist, do something unexpected: build a laser turret not to kill, but to draw the weather on the wall.

Continue reading “A Laser Drawing Machine For Flashes Of Creativity” →

Node-RED Laser Shooting Gallery Goes Anywhere

January 14, 2020 by Kristina Panos 6 Comments

When you think of a shooting gallery, you might envision a line of tin cans set up along a split-rail fence, or a few rows of ducks or bottles lined up at a carnival. But what do these have in common? You, standing in one spot, and shooting in the same general direction. You’re exposed! If those targets could shoot back, you’d be dead within seconds. Wouldn’t it be more fun if the targets were all around you in 360°? We think so, too.

So how could you possibly set up a shooting gallery this way? [Another Maker] already solved that problem for you with ESP32s and Node-RED (YouTube). Each target has an ESP32, a laser sensor, and an LED that lights up when the target is ready, and turns off once it’s been hit. They all make an enticing ‘shoot me’ sound that goes with their graphics, and a second mp3 plays upon direct hit.

The PVC gun houses an ESP8266, a laser module at the end of the barrel, and runs on a cylindrical USB battery slipped down in the secondary grip. [Another Maker] can spread the targets out far and wide, as long as they all stay in range of the localized WiFi access point.

The best part is that the Node-RED system is target-agnostic — it doesn’t care how many you have or how they’re made, and it can juggle up to 250 of them. Because of the way the target objects are programmed, it would be quite easy to add actuators that make them drop down or fall backward when hit. You could also implement [Another Maker]’s fantastic suggestion of hitting arcade buttons with NERF darts instead. Charge those lasers and fire at the break button to see the demo and walk-through video.

If you plan to knock the targets down or over in your implementation, you’ll want an easy way to reset them. Here’s a scrap-built shooting gallery that uses a windshield wiper motor to set ’em back up.

Continue reading “Node-RED Laser Shooting Gallery Goes Anywhere” →

Subterranean Uses For LIDAR: Cave Surveys

December 28, 2019 by Sharon Lin 11 Comments

LIDAR has gained much popularity as a means for self-driving cars to survey the space around them. At their most basic, LIDAR is a surveying method that uses lasers to paints the space around the sensors and assembles the distances measured from reflected light into a digital three-dimensional representation. That’s something that has quite a number of other applications, from surveying ancient ruins and rainforests from a bird’s eye view to developing 3D models of indoor spaces.

One fascinating use of LIDAR technology is to map out the routes inside caves, subterranean spaces that are seldom accessed by humans apart from those with specialized equipment and knowledge of how to safely traverse the underground terrain. [caver.adam] has been working on his Open LIDAR project for a few years using an SF30-B High Speed Rangefinder and laser device for a dual-system atop a gimbal with stepper motors for cave scanning.

Originally an entry in the 2016 Hackaday Prize, [Adam] has continued to work on the project. The result shown in the video below is a cheaper 3D LIDAR setup that works by rotating the laser distance module on 2 axes with a sensor centered at the center of rotation. It works for volumetric calculations, detects change over time, and identifies various water patterns and rocks on a surface map. Compared to notebooks, tape measures, and compasses, it’s certainly a step up in cave surveying technology.

Check out some other past underground surveying projects, such as Iowa City’s beer caves scanning projects and National Geographic’s 2014 expedition of the Titan Chamber in southern Guizhou Province in China.

Continue reading “Subterranean Uses For LIDAR: Cave Surveys” →

Use Blueprint Process To Print On Fabric With Lasers

December 18, 2019 by Gerrit Coetzee 11 Comments

[Shih Wei Chieh] has built a laser cyanotype printer for fabrics. You know, for art!

How do you get an inkjet head on a shoe or a couch? Most printing processes require a flat surface to print. But hearkening back to the days when a blueprint was a blueprint, a mixture of an iron salt and an acid are mixed and applied to a surface an interesting reaction occurs when the surface is exposed to UV light. The chemicals react to form, of all things, prussian blue. After the reaction occurs simply washing away the remaining chemicals leaves a stable print behind.

[Shih Wei Chieh] uses two galvanometers and a laser to cure the fabric. He uses a slightly newer process which reduces the exposure time required. This lets him print very large pictures, but also on uneven surfaces. As you can see in the video, viewable after the break, the effect is very pretty. There’s a new way to have the coolest pen plotter on the block.

Continue reading “Use Blueprint Process To Print On Fabric With Lasers” →