Psst…wanna buy a laser cutter, but not ready to sell your internal organs? Nortd Labs’ Lasersaur project aims to create an open source large-format laser cutter/engraver that undercuts (har har!) the cost of commercial models by an order of magnitude.
Continue reading “BAMF2011: Lasersaur Is One BIG Laser Cutter!”
This circuit illustration adds a scrolling paper feeder to the bed of a laser cutter. In the video after the break you can see that the actual assembly is put on the bed of the laser cutter. After the laser has cut out the specified pattern, the scroll is wound to move an un-cut portion into place. It uses a servo motor to drive one of the spools.
An Arduino Uno with a servo shield is being used for this application. It has one button which winds one spool for a pre-programmed period of time. There’s a few issues with this setup, namely that it’s not tied into the CNC program that runs the laser. There’s also a lack of precision when using a continuously rotating servo like this. If it were upgraded to use a stepper motor and patched into the CNC hardware this would make cutting new scrolls for your player piano a breeze.
Here’s a project that does the opposite, it takes old player piano rolls and digitizes them.
Continue reading “Cutting Paper Scrolls With Frickin’ Lasers”
Even though it’s a bit late for April Fool’s jokes, [Ameres] wrote in to share a project guaranteed to catch your friends (or enemies) by surprise.
Like us, he had some old CD-ROM drives sitting around and thought that there must be some way to put them to good use. He gutted one, saving the laser’s carrier unit for use as his mechanical trigger. He placed the unit above a doorway, soldered a pin on to the end of the laser carrier, and positioned a water balloon at the end of the CD-ROM’s rails. The laser carrier’s motor was then connected to a photocell located about half way down the side of the door.
He mounted a laser on the far side of the door, which is pointed at the photocell. Once the laser beam is broken, the CD-ROM motor is actuated, popping the balloon over the unsuspecting victim.
It’s not the most high-tech prank out there, but how high tech does a water prank need to be? We just wonder how easy it would be to attach one of these things to our cube at work…
Have any ideas as to how he can make a bigger splash with his friends? Share them with us in the comments.
Instructables user [PenfoldPlant] is a big fan of indoor rock climbing, and while watching others make difficult climbs, he has often wondered if he could follow the same route up the wall. Unfortunately, aside from watching the other climbers and hoping to remember the path they have taken, he found there isn’t much you can do to ensure that you have precisely replicated the climb.
He thought awhile and came up with a laser tracking system that can be used to record a climber’s ascent, then replay it any number of times. This allows climbers to be able to replicate other climbers’ paths as well as compete against one another in timed races.
This works much like the “ghost” feature found in most racing games, though the process is half manual/half automated. The initial ascent is recorded by manually tracing the climber’s route with a laser pointer as they climb. The path is recorded and then can be replayed, courtesy of the onboard Arduino.
It really is a neat system, and while it works pretty well already, we think there is still room for enhancement. It wouldn’t be extremely difficult to have the climber wear some sort of light beacon that could be tracked using a web cam or other recording device, taking the manual labor out of the equation. In that case however, we imagine the Arduino would need to be swapped out for something a touch more powerful.
Stick around for a quick video of the tracking system in action.
Continue reading “Laser Tracker Replays Competitive Rock Wall Climbs”
[Gordon] sent us a tip about this simple laser trip wire system after reading yesterday’s post on a more complicated laser security unit. That build did a lot to provide functionality, such as a system to disarm the trip wire, and a robust light detection circuit. This time around there’s more happening with smoke and mirrors than with electronics.
[The Timmy] built this simpler version based on a laser trip system from Afrotechmods (video of that one is embedded after the break). He had a bag full of small square mirrors which he attached to a wall with some poster putty. A laser module shines a beam of light onto a cadmium sulfide sensor after it bounces around the optical network for a while. That CdS sensor controls an N-channel MOSFET, switching it off when light is detected and on when the intensity of the laser is absent. This example just turns an LED on and off, but since it uses logic-level voltages you can choose to add a microcontroller to the mix if you have other plans in mind.
Instructables user [EngineeringShock] has been hard at work building a laser trip wire security system, complete with a combination lock. The security system works just like you see in the movies, employing an array of mirrors to bounce the laser across an opening several times in order to secure the space.
A PIC18F1220 micro controller sits at the center of the alarm and handles the majority of its functions. It takes input from the laser detection circuit, triggers the buzzer, as well as arms and disarms the entire alarm system. An LS7222 digital lock handles the passcode verification side of things, taking input from a 16-button matrix keypad, and telling the PIC when the proper code has been entered.
As you can see in the video below, the alarm system works and the buzzer is quite loud. There is one small problem however – the alarm only arms itself after the proper code has been entered and the lights have been turned off. The light sensing circuit he uses is too sensitive and can only operate in darkness, though he discusses the ability to add a more accurate sensing solution.
If you are interested in reading more about laser tripwire security systems, check out this similar passcode-based system, this alarm system built into a toy, and this Arduino-based alarm system.
Continue reading “Laser Tripwire Alarm System Uses Mirrors To Increase Coverage”
After reading over the proceedings of the 2005 SIGGRAPH, [Dan] realized he could reproduce one of the projects with $50 worth of equipment and some extreme cleverness.
[Dan]’s dual scanning laser camera operates by scanning a laser across an object. The light reflected from the object illuminates a flat surface, and this light is measured by a photocell. After measuring the resistance of the photocell, an image can be reconstructed from the light reflected off the flat surface. The result is quite ingenious, and we’re very grateful [Dan] gave us a great walkthrough with the code and theory of operation.
The project was covered in this Slashdot story a from a few years ago, and we’re surprise no one has bothered to cobble this project together. It’s a very simple build – two servos to control the x and y axes of the laser scanner, a photocell, and an ATMega board. Dan says the microcontroller isn’t even necessary, and this ‘remote imaging’ could be done with an ADC hooked up to a parallel port.
[Dan] was kind enough to to give us a video of his contraption in action. A very nice build from a very accomplished guy.
