Hacking A Cheap Action Cam Into A Dashcam With A Microcontroller

September 25, 2020 by Danie Conradie 15 Comments

Repurposing commodity electronics is one of the true forms of hacking, and it’s always the simple little hacks that lead to big ones. [Everett] wanted to use a $20 GoPro clone as a dash cam, so he wired a microcontroller into it to automate some actions and make it practical.

The camera turns on automatically when connected to external power like a car charger, but starting and stopping a recording and power down all had to be done manually. [Everett] wanted to automate these functions, so he opened up the camera and started probing with an oscilloscope. He found the power button, record button, 3.3 V and external 5 V traces conveniently next to each other in the top of the camera.

To automate the required functions, he wired in a PIC10 on a small breakout board, powered by the 3.3 V line. It detects if 5 V is connected to the charging port on start-up via an N-channel FET, then automatically starts a recording. When the 5 V power is switched off with the car, it waits 10 seconds before stopping the recording and switching off the camera. If no external 5 V is not detected on start-up the microcontroller does nothing, which allows the camera to be used as a normal handheld. [Everett] mounted the camera to his rearview mirror with a magnetic bracket made using a combination of a 3D printer and 3D pen.

This is a simple and practical little hack, and the firmware is available on Github. Cheap dashcams are available for similar prices, but you won’t get any hacking satisfaction that way.

The very nature of actions cameras inspire hacking. You can simply add an external battery with the help of a 3D printer, or go all out and build a gimballed helmet cam from scratch

Building A USB-C Charger For Canon NB-4L Batteries

September 23, 2020 by Tom Nardi 17 Comments

One of the most appealing aspects of USB-C is that it promises to be a unified power delivery system. You’ll no longer need to have a separate power cords for for your phone, camera, and laptop; physically they’ll all use USB-C connectors, and the circuitry in the charger will know how much juice to send down the line for each gadget. But in reality, we’ve all got at least a few pieces of older equipment that we’re not about to toss in the trash just because it doesn’t support the latest USB spec.

Case in point, the old Canon camera that [Purkkaviritys] modified to take infrared pictures. Instead of abandoning it, he decided to make a custom USB-C charger for its NB-4L batteries. Since they’re just single cell 3.7 V lithium-ions, all he had to do was wire them up to the ubiquitous TP4056 charger module and design a 3D printed case to hold everything together.

He did go the extra mile and replace the SMD charging indicator LEDs on the PCB with 5 mm LEDs embedded into the 3D printed enclosure, though you could certainly skip this step if you were in a hurry. We imagine if you print the enclosure in a light enough color, you should be able to see the original LEDs glowing through the plastic.

This project is yet another example of how incredibly useful the TP4056 module really is. If there’s even a chance you might want to build a rechargeable gadget in the near future, you should have a few of these cheap boards ready to go in the parts bin.

Schlieren On A Stick

August 25, 2020 by Bryan Cockfield 10 Comments

Schlieren imaging is a technique for viewing the density of transparent fluids using a camera and some clever optical setups. Density of a fluid like air might change based on the composition of the air itself with various gasses, or it may vary as a result of a sound or pressure wave. It might sound like you would need a complicated and/or expensive setup in order to view such things, but with a few common things you can have your own Schlieren setup as [elad] demonstrates.

His setup relies on a cell phone, attached to a selfie stick, with a spherical mirror at the other end. The selfie stick makes adjusting the distance from the camera to the mirror easy, as a specific distance from the camera is required as a function of focal length. For cell phone cameras, it’s best to find this distance through experimentation using a small LED as the point source. Once it’s calibrated and working, a circular field of view is displayed on the phone which allows the viewer to see any change in density in front of the mirror.

The only downside of this build that [elad] notes is that the selfie stick isn’t stiff enough to prevent the image from shaking around a little bit, but all things considered this is an excellent project that shows a neat and useful trick in the photography/instrumentation world that could be useful for a lot of other projects. We’ve only seen Schlieren imaging once before and it used a slightly different method of viewing the changing densities.

Continue reading “Schlieren On A Stick” →

Vizy The AI Camera Aims To Ease Machine Vision

August 17, 2020 by Donald Papp 17 Comments

Cameras are getting smarter and more capable than ever, able to run embedded machine vision algorithms and pull off tricks far beyond what something like a serial camera and microcontroller board would be capable of, and the upcoming Vizy aims to be even smarter and easier to use yet. Vizy is the work of Charmed Labs, and this isn’t their first foray into accessible machine vision. Charmed Labs are the same folks behind the Pixy and Pixy 2 cameras. Vizy’s main goal is to make object detection and classification easy, with thoughtful hardware features and a browser-based interface.

Vizy can identify common birds with “Birdfeeder”, one of the several built-in applications that uses local processing only.

The usual way to do machine vision is to get a USB camera and run something like OpenCV on a desktop machine to handle the processing. But Vizy leverages a Raspberry Pi 4 to provide a tightly-integrated unit in a small package with a variety of ready-to-run applications. For example, the “Birdfeeder” application comes ready to take snapshots of and identify common species of bird, while also identifying party-crashers like squirrels.

The demonstration video on their page shows off using the built-in high-current I/O header to control a sprinkler, repelling non-bird intruders with a splash of water while uploading pictures and video clips. The hardware design also looks well thought out; not only is there a safe shutdown and low-power mode for the Raspberry Pi-based hardware, but the lens can be swapped and the camera unit itself even contains an electrically-switched IR filter.

Vizy has a Kickstarter campaign planned, but like many others, Charmed Labs is still adjusting to the changes the COVID-19 pandemic has brought. You can sign up to be notified when Vizy launches; we know we’ll be keen for a closer look once it does. Easier machine vision is always a good thing, because it helps free people to focus on clever ideas like machine vision-based tool alignment.

Building A Gimballed Motorcycle Helmet Camera From Scratch

August 16, 2020 by Mike Szczys 10 Comments

[Nixie Guy] has hit all of important design elements in a single motorcycle helmet-cam project which packs in so much that the build log spans three posts. These cameras need to stand up to the elements and also to being pelted by insects at 80 MPH. They need to attach securely to the helmet without interfering with vision or movement of the head. And you should be able to adjust where they are pointing. The balance of features and cost available in consumer cameras make this list hard to satisfy — but with skills like these the bootstrapped camera came out great!

Where can you get a small, high quality camera? The drone industry has been iterating on this problem for a decade now and that’s where the guts of this creation come from. That produced an interesting issue, the board of the CADDX Turtle V2 camera gets really hot when in use and needs to have air flowing over it. So he threw a custom-milled heat sink into the side of the SLA resin printed housing to keep things somewhat cool.

Since the mill was already warmed up, why not do some mold making? Having already been working on a project to use a casting process for soft PCB membranes, this was the perfect technique to keep the buttons and the SD card slots weather tight on the helmet cam. A little pouch battery inside provides power, and the charging port on the back is a nice little magnet job.

Everything came together incredibly well. [Nixie Guy] does lament the color of the resin case, but that could be easily fixed by reprinting with colored resin.

While you’re bolting stuff onto your helmet, maybe some excessive bling is in order?

Continue reading “Building A Gimballed Motorcycle Helmet Camera From Scratch” →

OAK Vision Modules Help You See The Forest And The Trees

August 9, 2020 by Roger Cheng 13 Comments

OpenCV is an open source library of computer vision algorithms, its power and flexibility made many machine vision projects possible. But even with code highly optimized for maximum performance, we always wish for more. Which is why our ears perk up whenever we hear about a hardware accelerated vision module, and the latest buzz is coming out of the OpenCV AI Kit (OAK) Kickstarter campaign.

There are two vision modules launched with this campaign. The OAK-1 with a single color camera for two dimensional vision applications, and the OAK-D which adds stereo cameras for that third dimension. The onboard brain is a Movidius Myriad X processor which, according to team members who have dug through its datasheet, have been massively underutilized in other products. They believe OAK modules will help the chip fulfill its potential for vision applications, delivering high performance while consuming low power in a small form factor. Reading over the spec sheet, we think it’s fair to call these “Ultimate Myriad X Dev Boards” but we must concede “OpenCV AI Kit” sounds better. It does not provide hardware acceleration for the entire OpenCV library (likely an impossible task) but it does cover the highly demanding subset suitable for Myriad X acceleration.

Since the campaign launched a few weeks ago, some additional information have been released to help assure backers that this project has real substance. It turns out OAK is an evolution of a project we’ve covered almost exactly one year ago that became a real product DepthAI, so at least this is not their first rodeo. It is also encouraging that their invitation to the open hardware community has already borne fruit. Check out this thread discussing OAK for robot vision, where a question was met with an honest “we don’t have expertise there” from the OAK team, but then ArduCam pitched in with their camera module experience to help.

We wish them success for their planned December 2020 delivery. They have already far surpassed their funding goals, they’ve shipped hardware before, and we see a good start to a development community. We look forward to the OAK-1 and OAK-D joining the ranks of other hacking friendly vision modules like OpenMV, JeVois, StereoPi, and AIY Vision.

Bringing The Pi Camera Into Focus With LEGO

July 22, 2020 by Moritz v. Sivers 6 Comments

Ever since the high-quality camera for the Raspberry Pi was released a few months back it has been the center of attention for many hacks. In this quick build [Martin Mander] shows us how to make a servo-powered focusing mechanism entirely from LEGO.

The inspiration for this project came to him while he was working on his 1979 Merlin Pi Camera and found that setting the focus just right is vital in order to get good quality pictures. So he set himself the goal to build a mechanism that allows him to focus the camera precisely and remotely.

It is the plethora of LEGO-compatible parts that are available off-the-shelf that make such a project possible without the use of any 3D printed components. He not only found a LEGO-compatible continuous rotating servo but also a LEGO-compatible case for the Pi, and a LEGO cogwheel which almost fits exactly onto the camera lens. He also added a tripod mount to the case that allows him to set up the camera anywhere. The camera and focussing mechanism are controlled with a custom GUI based on guizero Python 3 library and the camera can be accessed remotely via VNCViewer.

If you prefer 3D printing over LEGO there are also other stylish Raspi HQ camera builds.

Video after the break.

Continue reading “Bringing The Pi Camera Into Focus With LEGO” →