Here’s an interesting experiment that attempts to measure the quality of a linear rail by using a form of visual odometry, accomplished by mounting a camera on the rail and analyzing the video with open-source software usually used to stabilize shaky video footage. No linear rail is perfect, and it should be possible to measure the degree of imperfection by recording video footage while the camera moves down the length of the rail, and analyzing the result. Imperfections in the rail should cause the video to sway a proportional amount, which would allow one to characterize the rail’s quality.
To test this idea, [Saulius] attached a high-definition camera to a linear rail, pointed the camera towards a high-contrast textured pattern (making the resulting video easier to analyze), and recorded video while moving the camera across the rail at a fixed speed. The resulting video gets fed into the Deshaker plugin for VirtualDub, of which the important part is the
deshaker.log file, which contains X, Y, rotate, and zoom correction values required to stabilize the video. [Saulius] used these values to create a graph characterizing the linear rail’s quality.
It’s a clever proof of concept, especially in how it uses no special tools and leverages a video stabilizing algorithm in an unusual way. However, the results aren’t exactly easy to turn into concrete, real-world measurements. Turning image results into micrometers is a matter of counting pixels, and for this task video stabilizing is an imperfect tool, since the algorithm prioritizes visual results instead of absolute measurements. Still, it’s an interesting experiment, and perfectly capable of measuring rail quality in a relative sense. Can’t help but be a bit curious about how it would profile something like these cardboard CNC modules.
Here’s [Tom Parker] showing off a brushless motor gimbal stabilizer for his GoPro camera. We saw a similar project a couple of weeks back that featured a 3d printed quadcopter mount. This offering is meant to be held in your hands. It keeps the subject in frame even if the cameraman’s hands pitch and roll (we figured aeronautical terms were best here). This image shows him demonstrating a level camera as he quickly rolls the frame from one side to the other. It doesn’t compensate for yaw, which is something he may change in the next iteration. We already like the results he’s getting with it.
About 3:15 into the video demo below we get a very quick description of the build itself. He started it as a project at University. Fabrication included work on a 3D printer, laser cutter, and vacuum forming machine. The grips are bicycle handlebar components. To overcome the stabilization system the operator has access to a joystick. Without this you’d never be able to aim the camera up or down because of auto-leveling.
Continue reading “Showing Off A High-performance Brushless Motor Camera Gimbal”
Flashlights are so 20th Century. Be it the incandescent type that popped up very early on, or LED models with came around in the 90’s, there’s not much excitement to the devices. But [Sriranjan Rasakatla] is doing his best to change that. This is his WAY-GO Torch, an intelligent flashlight (a Smart Light?) that will not just light your path, but overlay useful data on it.
At the front of the unit a pico projector is housed on a jointed assembly. This allows the device to project data on the ground in front of you. Using a digital compass and GPS module, it can show the polar coordinates, guide you on your way, or provide information about the buildings around you. The motorized mount provides image stabilization based on IMU data. Check out the demonstration video after the break. It shows general functionality in the first part of the clip, with some footage of the stabilization system at about 4:30.
This really does seem like it came right out of a Sci-Fi novel. It’s useful, but the complexity makes it surprising that [Sriranjan] was able to pull it off. We wonder how the battery life is on the device, but it can’t be any worse that one of those really huge flashlight builds.
Continue reading “Intelligent Flashlight Will Literally Show You The Way”