Something you may have seen previewed on my Youtube page was this “automated cigar box” that I haven’t quite figured out a good name for. Several interesting names, such as the “CopBox,” “RedVSBlue,” and “Red Chomper” have been suggested, but if you feel you have a better name, be sure to let me know in the comments.
Even though I say “red” and “blue” at first to cause it to open, what really drives this device Read more »
ATtiny, arduino, and a micro servo
This method may not be pretty, but for crude servo control with the ATtiny chip, this method should work. I programmed it using an Arduino Uno as shown here.
Hobby servos work by taking the length of time a pulse of electricity is sent to the “signal” input. If it is 1.5 milliseconds (ms), it moves to the middle of it’s travel, 2 ms to the right, and 1 ms to the left. This excellent paper illustrates this, as well as some standard connector colors, which have helped me with some of my projects.
For my “tiny useless machine,” I needed a way to control a servo using the ATtiny chip. Accuracy didn’t have to be great, so what I did was used the delay command to make the pulse either 1 millisecond (delay 1) or 2 milliseconds (delay 2). The code below will show what I mean, Read more »
World’s Smallest? I’m not sure, but it’s definitely smaller than any other “Useless Machine” that I’ve seen so far*. I’m sure a tinier machine could be built, so if you have one, be sure to let me know in the comments. To explain things, here’s a video of it in various experimental stages:
If you’re not familiar with the “useless machine” concept, you flip a switch, and it turns itself off. Clever idea, but not mine originally.
This model was very much done “free-form” I had a general idea of what I wanted to do (build a tiny useless machine using a sub-micro servo and ATTiny chip), but I didn’t draw any CAD models. I just cut as I went with my milling machine and Dremel tool. Photos at different points in the process are after the “read more.”
Panning around the internals of my “Tiny Useless Machine”
As you can see, the results are quite shoddy, but as an engineer, it was refreshing to make something without all the details worked out. OK, maybe that’s what I do a lot of the time as an engineer, but at least there was no pressure to get it done and working correctly this time!
Most “useless machines” use a DC motor, but this one uses a sub-micro servo (like this one from Amazon) and an ATtiny chip (my introduction to this cool little chip), to cause a Read more »
If you like to experiment with robots and electronics as I do, you will undoubtedly run into a situation where you wanted to use a hobby servo with a breadboard. Unfortunately, to many including myself, this has meant removing the universal, or “JR” connector housing and just plugging it into the breadboard. Tinning the leads (see this video – not mine) after chopping off the connector makes insertion a bit easier, but what about a non-destructive attachment method?
What about a double long-sided header? All you need for this simple hack is soldering equipment, and at least 6 snap-off headers with .1 inch centers. You can find these on Amazon, Read more »
Drawing a circle with lasers, as seen here, was an interesting project, and really stretched my ability trigonometry-wise (read on for more details). What would be even better, however, would be to take an image (gif, jpg, or otherwise) and convert it into a light graffiti automatically. This is my latest experiment with servos, lasers, and the Python programming language using a pyMCU.* Check out the results in this video:
One should note that the example images are not from the laser moving around in the video, since the same camera is used for the video and long-exposure light graffiti shots. The physical setup for this fixture is explained in the “servo circle” light graffiti post, and if you want to know how light-graffiti works in general, here’s my intro. Basically, one opens up the camera’s shutter, records all light coming in, and merges it into an image as if it happened at one time. Because of this, a servo putting little light dots on a screen can appear to be a coherent image as if it was all there at one time.
Here is the Python code that I used to program my pyMCU* for this project. The math is a bit less complicated than the circle code, as I just incremented the “mb.PulseOut”* command for the pyMCU by one for each pixel. The code is based on my previous pixel-machining experiment, and works in a very similar manner.
Moving the servos, and laser timing issues:
One thing that was different with this program is that the pixel-machining routine generated Gcode for a CNC router, so the machine takes care of actually getting the router to where it’s supposed to go. In contrast, Read more »
