[Peter] wanted a camera slider and found some inspiration on the good ole ‘net. He then gathered some parts and came up with his own design. We’ve seen camera sliders made from roller blade wheels before but never one that uses skateboard trucks as the carriage! On each truck axle are 2 bearings spaced apart without the skate wheels. Each pair of bearings rides on one of two 48 inch long closet rods supported between two push-up stands. The top portion from an old camera tripod makes a handy mount that allows adjustment of the camera’s aim.
Some camera sliders are manual operated. This one, however, is lead screw driven with a goal of keeping the camera moving at a constant rate. A disassembled hand drill provides the motor, gearbox and speed control necessary to turn the lead screw. Although it works well at slow speeds, [Peter] admits that it becomes less usable as the speed increases. This is mainly due to the 5/16 inch threaded rod lead screw oscillating and whipping around after reaching a certain RPM. If you stick with a straight run, a belt-driven system might make those faster movements more smoothly.
If you are interested in local wildlife, you may want to consider this wildlife camera project (Google cache). [Arnis] has been using his to film foxes and mice. The core components of this build are a Raspberry Pi and an infrared camera module specifically made for the Pi. The system runs on a 20,000 mAh battery, which [Arnis] claims results in around 18 hours of battery life.
[Arnis] appears to be using a passive infrared (PIR) sensor to detect motion. These sensors work by detecting sudden changes in the amount of ambient infrared radiation. Mammals are good sources of infrared radiation, so the sensor would work well to detect animals in the vicinity. The Pi is also hooked up to a secondary circuit consisting of a relay, a battery, and an infrared light. When it’s dark outside, [Arnis] can enable “night mode” which will turn on the infrared light. This provides some level of night vision for recording the furry critters in low light conditions.
[Arnis] is also using a Bluetooth dongle with the Pi in order to communicate with an Android phone. Using a custom Android app, he is able to connect back to the Pi and start the camera recording script. He can also use the app to sync the time on the Pi or download an updated image from the camera to ensure it is pointed in the right direction. Be sure to check out the demo video below.
If you like these wildlife cameras, you might want to check out some older projects that serve a similar purpose. Continue reading “Remote Controlled Wildlife Camera with Raspberry Pi”
It’s pretty common to grab a USB webcam when you need something monitored. They’re quick and easy now, most are plug-and-play on almost every modern OS, and they’re cheap. But what happens when you need to monitor more than a few things? Often this means lots of cameras and additional expensive hardware to support the powerful software needed, but [moritz simon geist] and his group’s Madcam software can now do the same thing inexpensively and simply.
Many approaches were considered before the group settled on using PCI to handle the video feeds. Obviously using just USB would cause a bottleneck, but they also found that Ethernet had a very high latency as well. They also tried mixing the video feeds from Raspberry Pis, without much success either. Their computer is a pretty standard AMD with 4 GB of RAM running Xubuntu as well, so as long as you have the PCI slots needed there’s pretty much no limit to what you could do with this software.
At first we scoffed at the price tag of around $500 (including the computer that runs the software) but apparently the sky’s the limit for how much you could spend on a commercial system, so this is actually quite the reduction in cost. Odds are you have a desktop computer anyway, and once you get the software from their Github repository you’re pretty much on your way. So far the creators have tested the software with 10 cameras, but it could be expanded to handle more. It would be even cooler if you could somehow incorporate video feeds from radio sources!
Continue reading “A Non-Infinite But Arbitrariliy Large Number of Video Feeds”
Holding a video camera while shooting video can lead to finished footage that has some serious shakes. Lucky for us there are some solutions to this problem such as a passive steady cam stabilizer or an active motor-driven gimbal. [Oscar] wanted a smooth-operating brushless motor gimbal but didn’t want to spend the big bucks it costs for a consumer setup so he went out and built his own.
[Oscar] didn’t have a CNC machine or 3D printer to help with his build. He made his gimbal with simple hand tools out of plywood and hardware store bracketry. In his build post, he talks about how it is important to keep the pivoting axes of the gimbal in line with the camera lens and what he did to achieve that goal. The alignment of the axes and the lens ensures that the video is stable while the gimbal adjusts to keep the camera’s angle constant.
[Oscar] purchased the brushless motors and motor controller which included a gyro sensor on a separate PCB board. The gyro is mounted to the camera mount and sends tilt information back to the controller that then moves the brushless motors to keep the camera level. The final project worked out pretty good although [Oscar] admits he still would like to tune the PID settings in the controller a little better. Check out the video after the break where the stabilized camera is compared to one that is not.
Continue reading “Resourceful DIY Brushless Hand-held Camera Gimbal”
It’s been a few years since the RTL-SDR TV Tuner dongle blew up the world of amateur radio; it’s a simple device that listens in on digital television frequencies, but it’s one of those tools that’s just capable enough to have a lot of fun. Now, we have a transmitting dongle. It’s only being used to transmit live HDTV from a Pi, but that in itself is very interesting and opens up a lot of possible builds.
The key piece of hardware for this build is a UT-100C DVB-T modulator. It’s a $169 USB dongle capable of transmitting between 1200-1350 MHz, and with a special edition of OpenCaster it’s possible to transmit over-the-air TV. There’s no amplifier, so you won’t be sending TV very far, but it does work.
On the Raspberry Pi side of the build, the standard camera captures H.264 video with raspivid, which is converted to a DVB compliant stream using ffmpeg. These are well-worn bits of software in the Raspberry Pi world, and OpenCaster takes care of the rest.
While this seems like the perfect solution to completely overbuilt quadcopters, keep in mind transmitting on the 23cm band does require a license. Transmitting in the UHF TV bands is a bad idea.
[Roy Shilkrot] and his fellow researchers at the MIT Media Lab have developed the FingerReader, a wearable device that aids in reading text. Worn on the index finger, it receives input from print or digital text and outputs spoken words – and it does this on-the-go. The FingerReader consists of a camera and sensors that detect the text. A series of algorithms the researchers created are used along with character recognition software to create the resulting audio feedback.
There is a lot of haptic feedback built into the FingerReader. It was designed with the visually impaired as the primary user for times when Braille is not practical or simply unavailable. The FingerReader requires the wearer to make physical contact with the tip of their index finger on the print or digital screen, tracing the line. As the user does so, the FingerReader is busy calculating where lines of text begin and end, taking pictures of the words being traced, and converting it to text and then to spoken word. As the user reaches the end of a line of text or begins a new line, it vibrates to let them know. If a user’s finger begins to stray, the FingerReader can vibrate from different areas using two motors along with an audible tone to alert them and help them find their place.
The current prototype needs to be connected to a laptop, but the researchers are hoping to create a version that only needs a smartphone or tablet. The videos below show a demo of the FingerReader. For a proof-of-concept, we are very impressed. The FingerReader reads text of various fonts and sizes without a problem. While the project was designed primarily for the blind or visually impaired, the researchers acknowledge that it could be a great help to people with reading disabilities or as a learning aid for English. It could make a great on-the-go translator, too. We hope that [Roy] and his team continue working on the FingerReader. Along with the Lorm Glove, it has the potential to make a difference in many people’s lives. Considering our own lousy eyesight and family’s medical history, we’ll probably need wearable tech like this in thirty years!
Continue reading “Trace Your Book or Kindle with the FingerReader”