Since I can’t really justify a super long post for both of these short items/topics but I still want to try and stay regular with my blogging, I’m going to be combining them into a single Franken-post. It’ll save you the facebook wall spam too.
Revamped Camera Slider
So almost immediately after my failure of a first-gen motorized slider, I immediately began thinking about how to achieve smoother and (more importantly) slower motion on my rig.The answer was unfortunately a little more involved than simply gearing down my motor by a few orders of magnitude. I needed a force-transmission method that was completely rigid, not relying on any sort of wire or thread. I had 2 options, use a wheel/gear on a track/rack gear, or use a threaded rod. Since you can get 6′ of threaded rod at Home Depot for under $10, I went with that option instead of trying to devise a dolly-side motorized wheel system.
The threaded rod you can buy at Home Depot is the most vanilla rod you can get. Zinc plated steel, with triangular threads. No guarantee of straightness, no guarantee of clean threads. If you shop smartly and inspect your merchandise before you buy, you should be okay for a cheapo DIY build like mine. If you want anything remotely resembling perfection though, Consider spending upwards of $25 on Acme Rod from a place like McMaster. You’ll know what material you’re getting, you’ll know how straight your rod will be, and the trapezoidal threads will give you better contact, less backlash. Also get ball bearings.. trust me on that. A few dollars for smooth rotation is well worth it. I didn’t get any because I wasn’t about to spend $10 for 2 because their shipping is what gets you on small orders.
Anyhow, I cobbled together a track for the threaded rod to turn in (just a V-shaped groove out of wood with metal surfacing to lower friction), as well as a gear reduction system to go from stepper motor to shaft. Since my rod wasn’t perfectly straight, the force needed to rotate it isn’t constant. On the “uphill” half of the turn the friction can sometimes overwhelm the stepper motor at low voltage, so I had to crank my power supply up to 7V to get smooth continuous motion. I may have to go even higher once I load the track with a camera.
Leave a Lost-Found Wallpaper/Message for your iSwag
Given that one of the easiest ways to help protect your Macbook has been to leave a message on the lock screen should a good samaritan find your lost laptop, I find it almost surprising that the same has not been more widely done on phones… although I suspect it has something to do with the complete lack of options to do so in the Settings app. There are apps that do it for you… none are really more than mediocre templates that may or may not serve your purposes. Best to just do it yourself.
With about 5 minutes in Photoshop/Gimp/etc, anyone can pretty much stamp their emergency (non-phone) contact information on a wallpaper. You can easily find free lockscreen templates online to help you position your information in an appropriate location (or just overlay it on a screenshot). For my lockscreen, I also slathered on a random texture for the hell of it underneath the transparent bars inherent in iOS for higher contrast when my phone’s screen is dim. I found that the upper-half of the screen is the best location to put information because it remains visible when you attempt to unlock the phone. That way even if your screen is covered with notifications, someone can still get to the information.