[Evan] always wanted a trackball for his arcade cabinet. It’s hard to play Missile Command with anything else, and Centipede with any other controller is just stupid. So he bought one, jury-rigged a mounting bracket for it, and then fried it by plugging the wiring harness in backwards. Doh!
But proving Edison’s famous statement that innovation is 1% inspiration and 99% having the right stuff in your junk bin, [Evan] dug deep and came out with one of twenty (!) old ball mice that he had purchased for just such an occasion. (Yeah, right.) Since a ball mouse is essentially an upside-down trackball, all that remained for him to do was reverse-engineer the mouse and swap its controller in for the busted trackball.
A simple hack, born of necessity, and well done. If you’re stuck with a crate of optical mice instead, consider turning them instead into optical laser rangefinders.
[Neumi] wrote in with a sweet robotics hack. It’s a 2D laser distance sensor (YouTube) made with a cheap line laser and an optical mouse’s flow-sensor chip used as a low-resolution camera. In one sense, it’s a standard laser-distance-sensor project. But it is clever for a whole bunch of reasons.
For one, using a mouse sensor as a low-res camera is awesome. It’s designed to read from a standard red LED, so the sensitivity is in just the right ballpark for use with a line laser. It returns a 30×30 pixel greyscale image, which is just about the right amount of data for a low-end microcontroller to handle and keep up with the framerate without resorting to coding tricks.
It’s also no coincidence that these sensors are available with lenses built in, for relatively cheap, on eBay. Apparently the quadcopter gurus use them as if they were mice to visually track their quad’s motion. Hacker spillover!
Detecting the laser line as it reflects off of whatever objects are lying on [Neumi]’s floor could also possibly prove difficult, and might produce false readings in the presence of background illumination. So [Neumi] takes two readings with the camera — one with the laser on and one with it off — and differences them. Done fast enough, this should reduce any non-laser sources down to the sensor’s noise floor. Finally, there’s some thresholding and averaging going on behind the scenes that help make everything work out right. The code is up on GitHub.
Not a bad build for a 2D laser distance system on a budget. If you want to shell out a bit more money, and are into a seriously involved build, this is probably the slickest we’ve seen in a long time. And if you’re thinking that you’ve heard of [Neumi] before, you’re right: we featured this 405mm laser PCB exposer / burner CNC machine just a few months ago.
Continue reading “Mouse Brains Plus Line Laser Equals Rangefinder”
[Thomas] loves his Logitech MX Master mouse, which has a pretty elaborate scroll-wheel mechanism. Perhaps too elaborate; it broke on him after a week of use, just when he was getting used to the feature. So what did he do? Took it apart and fixed it, naturally. And as a bonus, we get a guided tour of the interesting mechanism. Check out his video below to watch it in action.
The weighted scroll wheel switches between two different modes, one with a detent like you’re probably used to, and one where the wheel is allowed to spin freely for long-distance travel. And to do this, it’s actually got a little motor inside that rotates a cam and throws a lever into the side of the scroll wheel for the detent mode, and pulls the lever out of the way for free spins. It must also have some logic inside that detects how quickly the scroller is spun because it re-engages as soon as the scroll wheel stops.
Continue reading “Fixing A Complicated Scrollwheel”
No mice were harmed in the making of this non-lethal soda bottle mousetrap.
Depending on your opinion of these little critters, that could be a good thing or a bad thing. We don’t deny that mice are cute as all get-out, but when they do damage to foodstuffs that you’ve put an entire summer’s effort into growing, harvesting and preserving, cute isn’t worth much.
Our preference for taking care of rodent problems is either bioremediation or rapid cervical dislocation, but if you’re more of the catch-and-release type, this trap is for you. It’s just a 2-liter soda bottle on a wire pivot and mounted to a scrap wood frame; when the offending critter unwisely enters the neck of the bottle, its weight flips the bottle down and blocks the exit. Release is as simple as removing the bottle from the frame and letting Monsieur Jingles wiggle free. The questions of where to release and how many times you’ll keep catching the same mouse are left as an exercise for the reader.
Remember – a live catch trap is only humane if it’s checked regularly. To that end, maybe something like das Katzetelegraf could be added to this trap.
Continue reading “A Better Mousetrap, at Least for the Mouse”
We feel it’s healthy to cultivate a general desire for more neat tools. That’s just one of the reasons we like [doublecloverleaf]’s retro PC mouse. It certainly meets the requirement, the first computer mouse was wooden, and the mouse he used as the guts for this is so retro it belongs in the dollar bin at the thrift store.
To begin with, [doublecloverleaf] took a picture of the footprint of his aged, but trustworthy laser mouse. Using the photo in SolidWorks he built a model of the circuit board, and with that digitized, a mouse that suited his aesthetics around it. The final model is available on GrabCAD.
Edit: Woops, looks like we accidentally slandered a great Slovenian community CNC project. Check out the comments for more info. Original text in italics.
Next came the CNC. It looks like he’s using one of those Chinese 3040 mills that are popular right now. The electronics are no good, but if you luck out you can get a decent set of mechanics out of one. He did a two side milling operation on a wood block, using four small holes to align the gcode before each step, and then milled the bottom out of aluminum. Lastly, he milled the buttons out of aluminum as well, and turned a knurled scroll wheel on his lathe.
The end result looks exceedingly high end, and it would be a hard first guess to assume the internals were equivalent to a $10 Amazon house brand mouse.
Continue reading “Turn Your $10 Dollar Mouse Into A Fancy $10 Dollar Mouse With CNC”
[Nicolas Berger] submits his six degree of freedom mouse project. He hopes to do things like control a robot arm or fly an alien mothership.
We thought the construction was really neat; suspending a wooden ball in the middle of three retractable key rings. By moving the ball around you can control the motion of a cube displayed on the computer. We first thought this was done by encoders or potentiometers measuring the amount of string coming out of the key fobs. However, what’s actually happening is a little bit cleverer.
[Nicolas] has joined each string with its own 2 axis joystick from Adafruit. He had some issues with these at first because the potentiometers in the joysticks weren’t linear, but he replaced them with a different module and got the expected output. He takes the angle values from each string, and a Python program numerically translates the output from the mouse into something the computer likes. The code is available on his GitHub. A video of the completed mouse is after the break.
Continue reading “Joysix, Six Degree of Freedom Mouse Made From Retractable Key Rings”
No offense to [Douglas Engelbart] but the computer mouse has always seemed a bit of a hack to us (and not in the good sense of the word). Sure we’ve all gotten used to them, but unlike a computer keyboard, there is no pre-computer analog to a mouse. There are plenty of alternatives, of course, like touchpads and trackballs, but they never seem to catch on to the extent that the plain old mouse has.
One interesting variation is the pen mouse. These do rely on a pre-computer analog: a pen or pencil. You can buy them already made (and they are surprisingly inexpensive), but what fun is that? [MikB] wanted one and decided to build it instead of buying it.
The main parts of the pen mouse include a cheap mouse with a failing scroll wheel, a bingo pen, and the base from an old web camera. There’s also a normal-sized pen to act as the handpiece. The project is mostly mechanical rather than electrical. [MikB] took the mouse apart and cut the PCB to fit inside the base. The rest of the build is a construction project.
The result appears to work well. [MikB] includes instructions for installing the mouse correctly in Linux. The net effect is like a tablet but doesn’t’ require much space on your desk. We’ve seen plenty of mouse projects in the past, of course. We’ve even seen hacks for a head mouse if that’s your thing.