Not all of us have CNC machines, laser cutters and 3D printers, and I’ll bet most of us didn’t start out that well equipped. The low-cost drawing machine that [jegatheesan] made for his daughter reminds us that you can prototype, and then make a functioning mechanical Da Vinci with very basic materials and mostly hand tools. He also wrote his own drawing software, with an interface that has its own simplicity.
There really are a lot of things to like about [jegatheesan]’s project. He first works out the math himself by doing something the likes of which we’ve all enjoyed, digging out the old school trigonometry and algebra books for a refresher. Then he got started on his prototype, made using a cardboard tube for the main support and straws and safety pins for the drawing arms. He already had a motor shield for his Arduino but it supported only 2 servos, so he made his own 3-servo shield. In the end, the prototype told him he had to redo some calculations, allowing him to move on to the final machine.
One thing we can say about the final machine is that hot glue must truly be the maker’s connect-all — you won’t find many screws here. Even the servos are held in place with copious quantities of glue. And the mechanism for lifting the pen is also quite clever. The whole thing is mounted on two vertical guide rods, so that it can easily slide up and down. To get it to actually move up and down, he glued a toy car wheel off-center on a servo arm. When the servo turns, the off-center wheel acts like a cam, pushing down on the wooden base to either lift the machine up or lower it down, depending on where the wheel is in its rotation.
See his hackaday.io page for the full step-by-step development process. But first check out the videos below to see how impressive such a simply made machine is in action.
Continue reading “Impressive Drawing Machine For One Made So Simply”
While initially developed for use in large factory processes, computer numeric control (CNC) machines have slowly made their way out of the factory and into the hands of virtually anyone who wants one. The versatility that these machines have in automating and manipulating a wide range of tools while at the same time maintaining a high degree of accuracy and repeatability is invaluable in any setting. As an illustration of how accessible CNC has become, [Arnab]’s drawing robot uses widely available tools and a CNC implementation virtually anyone could build on their own.
Based on an Arudino UNO and a special CNC-oriented shield, the drawing robot is able to execute G code for its artistic creations. The robot is capable of drawing on most flat surfaces, and can use almost any writing implement that will fit on the arm, from pencils to pens to brushes. Since the software and hardware are both open source, this makes for an ideal platform on which to build any other CNC machines as well.
In fact, CNC is used extensively in almost everything now, and are so common that it’s not unheard of to see things like 3D printers converted to CNC machines or CNC machines turned into 3D printers. The standards used are very well-known and adopted, so there’s almost no reason not to have a CNC machine of some sort lying around in a shop or hackerspace. There are even some art-based machines like this one that go much further beyond CNC itself, too.
Continue reading “Robot Draws Using Robust CNC”
As microcontrollers become more and more common, we see more ways to get a lot of performance out of one chip. A great example of this was the ESP8266 which was originally seen as a cheap WiFi card but has since blossomed into its own dev platform thanks to the horsepower hidden within. To that end, [Martin] is trying to push the now-ubiquitous WiFi chip even further by rolling out his own LCD driver for it from scratch.
The display of choice is the KeDei LCD 3.5″ module which was originally intended for use with a Raspberry Pi. [Martin] points out that this display isn’t optimized for speed, but after everything is said and done he has its clock line running at 40 MHz. To get this kind of speeds from the LCD, he depopulates the first shift register and adds his own fast-propagation circuit to establish a more-traditional serial addressing mode. With use of a WLCD driver that [Martin] also wrote, it is now relatively easy to draw on the screen very quickly with an ESP module. Check it out in the video below.
If you’re looking for your own tiny, cheap, fast display, this is one cool way to do it but we would suggest spinning a carrier board for both the ESP and the added circuitry. We’re looking forward to future projects which puts devices like these inside of really tiny magic mirrors, or uses them in other places where a small graphical display would be handy.
Continue reading “Slow 3.5″ Raspberry Pi LCD Hacked to 40 MHz with ESP8266”
[Robottini] released plans for his robot, Cartesio, that is essentially an Arduino-controlled plotter made to create artwork. The good part about Cartesio is the low cost. [Robottini] claims it cost about $60 to produce.
The robot has an A3-size drawing bed and is practically the XY part of a 3D printer. In fact, most of the parts are 3D printed and the mechanical parts including M8 smooth rod. LM8UU bearings, and GT2 belts and pulleys. If you’ve built a 3D printer, those parts (or similar ones) should sound familiar.
The Arduino uses GRBL to drive the motors from GCODE. [Robottini] has three different workflows to produce drawings from applications like Inkscape. You can see some of the resulting images below.
We’ve covered GRBL before, and it is the heart of many motion control projects. If you’d rather draw on something less permanent, you might try this project.
Continue reading “Meet Cartesio, Robot Artist”
Mechanical drawings are an excellent way to convey design information, and while sophisticated 3D modeling is slowly taking over, with some companies accepting files over drawings, the mechanical drawing remains the written contract so to speak for complex parts with tolerances and non-modeled features.
But if you didn’t take a technical drawing class (typically Engineering Drawings 101), how do you learn? Well, if you have 15 minutes, this is an excellent video, which speaking from experience, covers the basics from the 101 course.
The lesson covers all the basics, from 2D projection, multi-view drawings, isometric projection, cross sectioning, linear dimensioning, basic tolerancing and alternate views.
Continue reading “An Excellent Primer for Sketching Mechanical Drawings”
Ever try signing your name with a mouse or a trackball? Not so easy. You could buy a graphics tablet with a pen. [Rahul Ramakrishnan] has a different approach. He took two 10-turn pots, and attached some strings and a washer. A pencil goes through the washer, and a BeagleBone Black reads the pots to determine what it is drawing on the paper. A couple of retractable badge lanyards keep tension on the string.
This ingenious design would be easy enough to replicate with any microcontroller that can read the two pots. The only awkward part is the need to press a button down when you want the device to treat the pencil as down (see the video below). It would probably be easy to rig up some switch on the pencil to make operation a little smoother.
Continue reading “Back to the Drawing Board”
[Maurice] recently built a clock that draws the time (Google Doc) on a white board. We’ve seen plenty of clock hacks in the past, and even a very similar one. It’s always fun to see the different creative solutions people can come up with to solve the same problem.
This device runs on a PIC16F1454 microcontroller. The code for the project is available on GitHub. The micro is also connected to a 433MHz receiver. This allows a PC to keep track of the time, instead of having to include a real-time clock in the circuit. The USB connector is only used for power. All of the mounting pieces were designed in OpenSCAD and printed on a 3D printer. Two servos control the drawing arms. A third servo can raise and lower the marker to the whiteboard. This also has the added benefit of being able to place the marker tip inside of an eraser head. That way the same two servos can also erase the writing.
The communication protocol for this systems is interesting. The transmitter shows up on [Maurice’s] PC as a modem. All he needs to do to update the time is “echo 12:00 > /dev/whiteboard”. In this case, the command is run by a cron job every 5 minutes. This makes it easy to tweak the rate at which the time updates on the whiteboard. All communication is done one-way. The drawing circuit will verify the checksum each time it receives a message. If the check fails, the circuit simply waits for another message. The computer transmits the message multiple times, just in case there is a problem during transmission.