If you’ve got a lot of spare parts lying around, you may be able to cobble together your own laser engraver without too much trouble. We’ve already seen small engraver builds that use an Arduino, but [Jeremy] tipped us off to [Xiang Zhai’s] version, which provides an in-depth guide to building one with a Raspberry Pi.
[Xiang] began by opening up two spare DVD writeable drives, salvaging not only their laser diodes but the stepper motors and their accompanying hardware, as well as a handful of small magnets near each diode. To assemble the laser, he sourced an inexpensive laser diode module from eBay and used a vise to push the diode into the head of the housing. With the laser snugly in place and the appropriate connecting wires soldered on, [Xiang] whipped up a laser driver circuit, which the Raspi will later control. [Xiang] worked out the stepper motors’ configuration by following [Groover’s] engraver build-(we featured it a few years back)-attaching the plate that holds the material to be engraved onto one axis and the laser assembly to the other.
Check out [Xiang’s] project blog for details explaining the h-bridge circuits as well as the Python code for the Raspi. As always, if you’re attempting any build involving a laser, please use all necessary precautions! And if you need more information on using DVD burners for their diodes, check out this hack from earlier in the summer
[Mark] recently finished his latest project, where he encrypts wireless communications between the new Intel Galileo and a Texas Instruments MSP430. The wireless interfaces used are the very common nRF24L01+ 2.4GHz transceivers, that had a direct line of sight 15 feet range during [Mark]’s tests. In his demonstration, the MSP430 sends an encrypted block of data representing the state of six of its pins configured as inputs. This message is then received by a sketch running on the Galileo and stored in shared memory. A python script then wakes up and is in charge of decrypting the message. The encryption is done using AES-128bits in Electronic Codebook mode (ECB) and semaphores are used to prevent simultaneous accesses to the received data. As it is the first project using an Intel Galileo we received, don’t hesitate to send us a tip if you found other ones.
Have you ever thought a particular project could be better if you could just control the file access directly? [Stavros Korokithakis] did, specifically for a backup program he was working on. What followed was the realization that writing a FUSE filesystem, particularly in Python, isn’t as complicated as it may seem. Really, through the power of open source, the heavy lifting has already been done for us. If you’d like to try it yourself, you’ll need to install fusepy. From that point, you simply need to define the filesystem methods you will be using.
Python isn’t going to win any speed contests in the filesystem space, but that isn’t really the point. Using this technology opens up a huge opportunity for new ways of accessing data. If you let your mind wander, you can conceive of encrypted filesystems, seamless remote data access, new key-value storage designs, etc. Perhaps even more interesting is the idea of using Python to communicate with a physical device… maybe a proc filesystem to keep track of your robot telemetry? We’d love to hear your ideas in the comments.
We had success using [Stavros’] example script on Linux and OSX. (Fair warning if you’re on a Mac, the pip version of fusepy seems to be linked against fuse4x rather than OSXFUSE, but once you’ve got the prerequisites installed, you’re golden.) We didn’t have a Windows machine to test. Can anyone confirm if the same is possible there?
Here’s a beautiful desktop CNC mill which had one big drawback: it used a proprietary interface for driving it. To increase the flexibility of the tool it was hacked to work with G-Code.
The project is a Hackaday Hackerspace Henchmen submission from rLab, the Reading Hackspace in the UK. [Barnaby] explains the entire project after the break. The machine itself wasn’t altered, but a translator script was written in Python after capturing a bunch of packets and working out the protocol. This script listens for G-Code and does the translation into the type of commands the machine is expecting to receive.
If you know of a CNC hack from your own hackerspace send us the story for a chance to win some loot.
Continue reading “HHH: Sniffing Proprietary CNC to Hack in G-Code Support”
There’s been some good .STL manipulation tips in this week.
The first one is called stl_tools, and it’s a Python library to convert images or text to 3D-printable STL files. The examples shown are quite impressive, and it even does a top notch job of taking a 2D company logo into 3D! We can see this being quite handy if you need some quick 3D text, and either don’t use CAD, or really just need a one click solution. Now if only .STLs were easier to edit afterwards…
Continue reading “STL Fun: Converting Images To STL Geometry”
After modifying his new manual treadmill to fit under his standing desk, [Brian Peiris] found a way to let him stroll all over the internet.
After removing the treadmill’s original time/distance display, [Peiris] reverse engineered the speed sensor to send data to an Arduino and his PC. We’ve seen a number of projects that interface treadmills with virtual worlds, but what really makes this project stand out is a simple script using the Throxy Python library which allows the treadmill to throttle his machine’s internet connection.
The end result is a browsing experience that reacts to how fast the user runs. In the demonstration video, you can see Peiris tiptoe through images or jog through YouTube videos. A minimum bandwidth setting keeps the connection live, so if you can’t make it all the way through that HD Netflix movie, taking a breather won’t time out the connection.
It’s certainly a great way to get in shape, or at the very least, it’ll make your ISP’s bandwidth cap feel a lot bigger.
Video after the jump.
Continue reading “Browsing the web one step at a time”
[Tyler Spilker’s] DDD project is a Digital Dead Drop system based on Python and a Raspberry Pi as a server. It’s pretty rough around the edges at this point — which he freely admits. But we like the concept and figure it might spark an interesting conversation in the comments section.
Now by far our favorite dead drop concept is this USB drive lewdly sticking out of a brick wall. But you actually need to be on-site where this drive is mortared into the wall in order to access it. [Tyler] instead developed a webpage that gives him a text box to enter his messages. These are encrypted using key pairs and pushed to his remote RPi server. This way he can write down his thoughts knowing they’re stored securely and never in danger of being accessed from a lost or stolen cellphone.
If free thought isn’t what you’re trying to transfer from one place to another you probably want something like a Pirate Box.