If a 3D printer is interrupted during a print, it will usually result in a junk part. Resuming the print can be very difficult. A group of researchers at MIT have built an add-on for 3D printers that uses a laser scanner to evaluate the state of the print, and allows the printer to restart.
While this will allow you to salvage some partially competed prints, the interesting application is switching between materials. In the image above, the lower piece was printed in ABS. The print was interrupted to change materials, and the top cube was printed in PLA. This allows for prints to mix materials and colors.
The add-on was tested with the Solidoodle 3D printer, and can be built for about $60. It requires a laser mounted to the print head, and a low-cost webcam for performing the measurements. While the group will not be continuing work on this project, they plan to open source their work so others can continue where they’ve left off.
After the break, we have a video of the printer performing a scan and resuming a print.
Over the past year, [Dave] has been hard at work on his human powered vehicle. One year and six hundred hours of build time later, the Radius T-T Velomobile is complete. This 80 lb. vehicle features a custom body, mirrors, and integrated lights.
The Radius T-T started out as a TerraTrike recumbent tricycle. [Dave] built the body by laying up fiber glass on a foam mold. To that he added a variety of 3D printed accessories such as lights and mirrors. Inside the cockpit, the driver can control turn signals and flashers.
[Dave]’s blog provides a massive amount of documentation on the build. Everything from 3D modelling of the vehicle in Blender to the rear view mirror design is discussed. This great looking build should move along quickly with its lightweight design, but we’re still waiting to hear how fast it goes. Either way, it should be a fun mode of transport which will definitely turn some heads.
[Dave] has some big plans to build himself a 1980’s style computer. Most of the time, large-scale projects can be made easier by breaking them down into their smaller components. [Dave] decided to start his project by designing and constructing a custom controller for his future computer. He calls it the Rabbit H1.
[Dave] was inspired by the HOTAS throttle control system, which is commonly used in aviation. The basic idea behind HOTAS is that the pilot has a bunch of controls built right into the throttle stick. This way, the pilot doesn’t ever have to remove his hand from the throttle. [Dave] took this basic concept and ran with it.
He first designed a simple controller shape in OpenSCAD and printed it out on his 3D printer. He tested it out in his hand and realized that it didn’t feel quite right. The second try was more narrow at the top, resulting in a triangular shape. [Dave] then found the most comfortable position for his fingers and marked the piece with a marker. Finally, he measured out all of the markings and transferred them into OpenSCAD to perfect his design.
[Dave] had some fun with OpenSCAD, designing various hinges and plywood inlays for all of the buttons. Lucky for [Dave], both the 3D printer software as well as the CNC router software accept STL files. This meant that he was able to design both parts together in one program and use the output for both machines.
With the physical controller out of the way, it was time to work on the electronics. [Dave] bought a couple of joysticks from Adafruit, as well as a couple of push buttons. One of the joysticks controls the mouse cursor. The other joystick controls scrolling vertically and horizontally, and includes a push button for left-click. The two buttons are used for middle and right-click. All of these inputs are read by a Teensy Arduino. The Teensy is compact and easily capable of emulating a USB mouse, which makes it perfect for this job.
[Dave] has published his designs on Thingiverse if you would like to try to build one of these yourself.
Heated beds for 3D printers help reduce the amount of curling and warping of parts. The warping happens when the part cools and contracts. The heated bed keeps the part warm for the entire print and reduces the warping.
As an upgrade to her Printrbot, [Erin] added a heated bed. The first plan was to DIY one using Nichrome wire, but heated beds are available at low cost. They’re basically just a PCB with a long trace that acts as a resistor. She added a thermistor to monitor temperature and allow for accurate control.
The Printrbot heated bed worked, but didn’t heat up quite quick enough. [Erin] was quick to scratch off the solder mask and solder new leads onto the board. This converted the board into two parallel resistors, halving the resistance and doubling the power.
This version heated up very quickly, but didn’t have a steady heat. The simple control that was being used was insufficient, and a PID controller was needed. This type of control loop helps deal with problems such as oscillations.
The Printrbot’s firmware is based on Marlin, which has PID support disabled by default. After rebuilding the code and flashing, the PID gains could be adjusted using g-codes. With the values tuned, [Erin]’s printer was holding steady heat, and can now print ABS and PLA with minimal warping.
Now that we’re starting to get serious about The Hackaday Prize we thought we’d take a look at the lives of some of the hackers who have submitted entries. Meet fl@C@, who is working on a Raman Spectrometer which is largely 3D printed and uses a Raspberry Pi. He was kind enough to answer all of our questions, some serious and some not so.
Creating. It’s probably no surprise that I have many hobbies…but hardware hacking is my life. I got my first taste with my dads Imsai 8080 (showing my age, but I was fairly young!)..Then it was an Apple][.. I really dove into that. I built my own from a bare pcb to a working machine when I was around 11 or 12. Just moved up from there.. Really went nuts when I got a job at a surplus electronics store in the silicon valley.. I rarely took home a paycheck.. I have a few other hobbies, I’m a private pilot…love flying. I built a pretty cool device that allowed me to datalog my flights, my heartrate, keep track of the fuel, it speaks and connects to the comm to remind me when to switch tanks, etc.. I’ll have to put that up on the project page.
Well…For my day job, I am a Network Engineer.. I can’t really say for which company, but it’s big.
My Passion is Going Big
I would say my passion is going big..if it’s worth doing…..it’s worth overdoing. I love coming up with ideas that would make a difference. The spectrometer I am working on is actually only a small part of a larger project I am working toward. There are never enough hours, or dollars to cover all of my ideas…but I always work as hard as I can to get there.. TLDR- I’m excited every day to wake up and make another step towards changing the world.
I work from home, but in the office… it’s definitely the snack machine. Seriously? We can’t build a machine that dispenses snacks without getting them stuck?
I’d say linux. I’ve been a fan of ubuntu for a while.. lately I’ve been playing with xubuntu. I don’t care for messing with computers..lol. I love electronics, hardware, software and all that.. but I do not geek out over PC hardware..I consider them another tool…they need to work when I need them to work. lol
Not sure if you want a breakdown of what gear I have….I have quite a bit and a pretty elaborate lab setup..but I’m really a bit of a minimalist when it comes to day to day use.. I use my scope when it’s appropriate..my logic analyzer (saelae logic rocks) pretty often.. but I’d say my go to device is usually my DMM since it’s what I tend to use most often…I have a few, but I like to use the one that connects up to my PC so I can make screenshots, and/or see it from a distance..
I would have to default to the mBed for this one..for general purpose. I started out like most people probably with the basic stamp waaaay back…and went through a few others..and settled on the mBed when there was just one device, but now they have so many platforms that you can fit to whatever need..and some of them are dirt cheap. I’m using the ST Nucleo041RE for the spectrometer project, and it’s only $10 at mouser. I have just started peering into FPGA stuff, I hope to get some more time to work with them very soon, I see lots of potential.. I never really used Arduino’s until the past year or two when I got into quadcopters..they have a purpose..and are ok for quick and dirty stuff since you can source a pro mini on ebay for like 3 bucks..
Python has become my best friend. C++ is great and all, I’ve been forced to use VB6 for work…where they even use winbatch……. But python works.. and it’s easy to crank something out quickly, and you can build some pretty robust stuff with it..
Well, I have a couple that come to mind immediately that I honestly would love to share with the world…but won’t just yet.. =) So, I’ll go with what is left…hopefully it’s plenty for now..
I’d love to build a fusor. I built my first tesla coil when I was 17.. I’d love to take the hobby fusor to the next step..
A Moon Rover. Seriously. And the vehicle to get it there. I think we all agree rockets and gasoline both need to go away. Mankind needs to reach out beyond what we’re confortable with.
A fully autonomous multirotor. I actually started this project..have it all layed out..but it’s not high enough on my priority list to make it the rest of the way..I have probably 80% of the parts new in a box..I’ve started doing a writeup on it..and hope to get it up soon.
Learn the Value of Knowing Where and How to Find the Information [You] need
I wish that everyone would learn the value of knowing where and how to find the information they need to accomplish a goal. Schools typically force you to memorize facts and information that is often worthless. I would like for people to learn instead how to be adaptive in their approach to problems, and understand that there is always more than one answer.. and there is a huge resource out there that will enable you to make educated decisions and reach grander goals. We live in a great time with that…and in that way, the internet is underutilized…
The timing was right…I thought this was an interesting and unique project..I had promised myself to try to be more open and share..this project was perfect since it has 3d parts people can print themselves, a raspberryPi, a sorta arduino and a cool laser…plus I figured there are several people out there that could either benefit from a low cost raman spectrometer, or at least benefit from some part of it..be it the parts I designed or just the understanding of how it works and what they’re used for…
I always keep an open mind, and consider any advice given.. There have been many aspects of this project that created a challenge.. This is my first serious venture into 3d printing this much stuff…I’ve never really worked with lasers and optics in such a way.. Avoiding spending thousands on optics was a major challenge. I have been doing all the research I can to understand the best approach to imaging…My first idea was to modify a webcam to take long exposures since the light reaching the camera will be fairly faint..after looking into that, it’s not just a lot of work and difficult to reproduce…but the cameras that others have modified are ancient and next to impossible to find. I wanted to go with a camera that anyone could find…the raspiCam kept surfacing as the best choice…so, the next challenge was how to get the long exposure…the raspiCam driver doesn’t really allow for 10-30 second exposures… so the next idea was to take several shots, and stack them to build a usable image.. so my latest approach is to take a 90fps video for a couple seconds, split that into individual frames, and stack those.. If anyone has suggestions in this area, I’d love to hear them.. I planned on using either mathematica or qtoctave from python, etc..
A Moon Rover. =) It’d probably most definately be a team effort.. But I think as a community, the skills are out there. And the google XPrize shouldn’t be the only game in town.. I think things are building up to this kind of stuff anyway, but someone’s got to be first.
Live Out Loud Every Day
I’d just like to say…putting this project on this site was a major debate for me. I grew up with parents that had secret clearances, and privacy was central. I’ve been trying to build up the courage to share my work and ideas with the world because I think it benefits everyone. This project is my first to share, and for it to be featured here, and for me to be honored with being the first the be featured is really amazing. I appreciate this whole community, I’ve learned a lot from it over the years and I hope to be able to give back and contribute more soon!
If you’re a 3D printing power user, you probably try to fit as many parts onto a single print job as possible. Most printing software has this built in to let you do that, but [Grégoire Passault] and his team thought they could do it better with their program Plater — it’s open source too.
They decided to make Plater after designing Spidey: an open-source 4-legged robot that makes use of 22 3D printed parts. The first few times they printed this took a long time because they had to manually arrange the parts — there had to be a better way!
Plater is a fairly simple program that lets you take in a bunch of STL files, set your print bed size and part spacing and then it creates an STL with as many parts in it as it can, organized on your print bed. Then you just have to load it up into your favorite slicing program and you’re good to go.
Seems like an excellent tool to add to your metaphorical 3D printing tool-belt!
Conductive filaments and printing solder are one thing, but what if you could spice up your 3D prints by embedding wire right inside the filament? That’s what [Bas] is doing, paving the way for printable electronics, PCBs, coils, and odd-shaped antenna.
The general idea of [Bas]’ technique of embedding thin copper wire inside a single layer of a print is to lay the wire down in front of the nozzle, effectively turning bare wire into insulated wire in whatever shape you can imagine. The trick, however, is figuring out how to put wire down in front of a nozzle. [Baz] accomplished this with a slew ring turned by a stepper motor connected to a 5th axis on the control board.
There are a few things this prototype doesn’t cover – cutting the wire, connecting the wire to components, fine-tuning, and a host of other things that prevent [Bas]’ machine from building real functional circuits. Despite these limitations, the machine could probably fabricate the secondary for a tesla coil right now, something that’s really annoying to make unless you have a lathe.