One of the limitations of the conventional Cartesian CNC platforms is that the working area will usually be smaller than its footprint. SCARA arms are one of the options to get around this, as demonstrated by [How To Mechatronics], with his SCARA laser engraver.
This robot arm is modified from the original build we featured a while back, which had a gripper mounted. It uses mainly standard 3D printer components with 3D printed frame parts. The arms lengths are sized to fold over the base and take up little table horizontal space when not in use. It can work in a large semi-circular area around itself, and if a proper locating and homing method is implemented, it can be moved around and engrave a large area section by section.
One of the challenges of SCARA arms is rigidity. As the cantilevered arm extends, it tends to lean over under its weight. In [How To Mechatronics]’s case, it showed up as skewed engravings, which he managed to mitigate to some degree in the Marlin firmware.
Another possible solution is to reduce the weight of the arms by moving the motors to the base, as was done with the Pybot or dual-arm SCARA printers like the RepRap Morgan.
Acorn BBC Master. Apple IIe. Ampex 270 Terminal. Vectrex game console. You’d be hard pressed to find a more diverse hardware collection in the average hacker’s lab. When you add seven Raspberry Pi’s, five CRT monitors, an analog oscilloscope and an LED wall to the mix, one starts to wonder at the menagerie of current and retro hardware. What kind of connoisseur would have such a miscellaneous collection? That’s when you spot smoke and fog machines sitting next to an RGB Laser.
Finally, you learn that all of this disparate paraphernalia is networked together. It is then that you realize that you’re not just dealing with a multi-talented hacker- you’re dealing with a meticulous maestro who’s spent lockdown finishing a project he started nearly twenty years ago!
AUVERN comes alive in a show of light and sound whenever someone enters its view.
The machine is called AUVERN and it’s the product of the creative mind of [Owen]. Taking advantage of advances in technology (and copious amounts of free time), [Owen] laboriously put his collection of older rigs to work.
A Python script uses a Kinect sensor’s input to control a Mac Mini running Digital Audio Workstation software. The operator’s location, poses and movements are used to alter the music, lights, and multimedia experience as a whole. MIDI, Ethernet, and serial communications tie the hardware together through Raspberry Pi’s, vintage MIDI interfaces, and more. Watch the video below the break for the technical explanation, but don’t miss the videos on [Owen]’s website for a mesmerizing demonstration of AUVERN in full swing.
Hackaday editors Elliot Williams and Mike Szczys debate the great mysteries of the hacking universe. On tap this week is news that Sam Zeloof has refined his home lab chip fabrication process and it’s incredible! We see a clever seismometer built from plastic pipe, a laser, and a computer mouse. There’s a 3D printed fabric that turns into a hard shell using the same principles as jamming grippers. And we love the idea of high-powered lasers being able to safely direct lighting to where you want it.
Take a look at the links below if you want to follow along, and as always, tell us what you think about this episode in the comments!
Most of us don’t spend that much time thinking about lightning. Every now and then we hear some miraculous news story about the man who just survived his fourth lightning strike, but aside from that lightning probably doesn’t play that large a role in your day-to-day life. Unless, that is, you work in aerospace, radio, or a surprisingly long list of other industries that have to deal with its devastating effects.
Humans have been trying to protect things from lightning since the mid-1700s, when Ben Franklin conducted his fabled kite experiment. He created the first lightning rod, an iron pole with a brass tip. He had speculated that the conductor would draw the charge out of thunderclouds, and he was correct. Since then, there haven’t exactly been leaps and bounds in the field of lightning rod design. They are still, essentially, a metal rods that attract lightning strikes and shunt the energy safely into the earth. Just as Ben Franklin first did in the 1700s, they are still installed on buildings today to protect from lightning and do a fine job of it. While this works great for most structures, like your house for example, there are certain situations where a tall metal pole just won’t cut it.
A Bayer array, or Bayer filter, is what lets a digital camera take color photos. It’s an array of tiny color filters that sit on top of a camera’s CCD. The filter makes it so that each sub-pixel in the image sensor only sees red, green, or blue light. The Bayer filter is an elegant tool that gives us color digital photos, but what would you do if you wanted to remove one?
[Les Wright] has devised a way to remove the Bayer filter from the Raspberry Pi Camera. Along with filtering red, green, and blue light for their respective sensors, Bayer filters also greatly reduce the amount of UV and IR light that make it to the CCD sensor. [Les] uses the Raspberry Pi camera in his Pi-based Spectrometer, and he wants to remove the Bayer filter to improve and expand its sensitivity.
Of course, [Les] isn’t the first one to want to do this. Some have succeeded in physically scratching the filter off of the CCD, but because the Pi Camera has vital circuitry around the outside of the sensor, scratching the filter off would likely destroy the circuitry. Others have stripped it off using chemical means, so [Les] gave this a go and destroyed no small number of cameras in his attempt to strip the filter off with solvents like DMSO, brake fluid, and industrial paint stripper.
A look at the CCD, halfway through the process.
Inspired by techniques used in industry, [Les] eventually tried to use a several-kW nitrogen laser to burn off the filter (which seems appropriate given his experience with lasers). He built a rig that raster scans the laser across the sensor using stepper motors to drive micrometer bases. A USB microscope was included to allow progress to be monitored, and you can see a change in the sensor’s appearance as the filter is removed.
After blasting off the Bayer filter, [Les] plugged his improved camera into his home-built spectrometer and pointed it outside. The new camera gives the spectrometer much more uniform sensitivity and allows [Les] to see further into the IR and UV bands. The spectrometer can even detect the Fraunhofer lines—subtle dips in the sun’s spectrum from absorption by molecules in the atmosphere.
This is incredible for a DIY setup and instrument, and we can’t wait to see what [Les] does next to improve his measurements. If your spectrometry needs are more mass than visual, take a look at this home-built mass spectrometer. Home spectrometers aren’t just for examining light spectra—they can also be used to judge the ripeness of fruit!
Tech companies like Google and Microsoft have been working on augmented reality (AR) wearables that can superimpose images over your field of view, blurring the line between the real and virtual. Unfortunately for those looking to experiment with this technology, the devices released so far have been prohibitively expensive.
While they might not be able to compete with the latest Microsoft HoloLens, these laser AR classes from [Joel] promise to be far cheaper and much more approachable for hackers. By bouncing a low-power laser off of a piezo-actuated mirror, the hope is that the glasses will be able to project simple vector graphics onto a piece of reflective film usually used for aftermarket automotive heads-up displays (HUDs).
Piezo actuators are used to steer the mirror.
[Joel] has put together a prototype of what the mirror system might look like, but says driving the high-voltage piezo actuators poses some unique challenges. The tentative plan is to generate the vector data with a smartphone application, send it to an ESP32 microcontroller within the glasses, and then push the resulting analog signals through a 100 V DC-DC boost converter to get the mirror moving.
The longevity of plastic is both a blessing and a curse. On the one hand, it’s extremely durable, inexpensive, and easy to work with, but it also doesn’t biodegrade and lasts indefinitely in the environment when not disposed of properly. While this can mean devastating impacts to various ecosystems, it can also be a benefit if you happen to pick this plastic up and also happen to have a laser cutter around.
After cleaning and sorting plastic that they had found from various places, including scraps from a 3D printing facility, the folks at [dinalab] set about turning waste plastic into something that would be usable once more. After sorting it they shredded it and then melted it into sheets. They found that a sandwich press yielded the best results, as it kept the plastic at a low enough temperature to keep it from burning. Once its off of the press and properly cooled, the flat sheets of plastic can be sent to the laser cutter to be made into whatever useful thing they happen to need.
Not only does this process reuse plastic that would otherwise end up in the landfill (or worse, the ocean), it can also reuse plastic from itself since the scraps can be re-melted back into sheets. Plastic does lose some of its favorable material properties with repeated heat cycles, but we’d have to imagine this is negligible for the types of things that [dinalab] is creating. Of course, you can always skip the heat cycles entirely and turn waste plastic directly into 3D printer filament instead.
