In our ceaseless quest to bring you the best from the cheaper end of the global electronics markets, there are sometimes gadgets that we keep an eye on for a while because when they appear they’re just a little bit too pricey to consider cheap.
Today’s subject is just such a device, it’s a minimalist infra-red camera using the 8 pixel by 8 pixel Panasonic AMG8833 thermal sensor. This part has been around for a while, but even though any camera using it has orders of magnitude less performance than more accomplished models it has remained a little too expensive for a casual purchase. Indeed, these mini cameras were somewhere above £50 ($70) when they first came to our attention, but have now dropped to the point at which they can be found for somewhere over £30 ($42). Thirty quid is cheap enough for a punt on a thermal camera, so off went the order to China and the expected grey parcel duly arrived.
It’s a little unit, 40 mm x 35 mm x 18 mm, constructed of two laser-cut pieces of black plastic held together by brass stand-offs that hold a PCB between them, and on the front is a cut-out for the sensor while on the rear is one for the 35mm OLED display.At the side on the PCB is a micro USB socket which serves only as a power supply. It’s fair to say that this is a tiny unit.
Applying power from a USB battery bank, the screen comes up with a square colour thermal picture and a colour to temperature calibration stripe to its left. The colours adapt to the range of temperatures visible to the sensor, and there is a crosshair in the centre of the picture for which the temperature in Celsius is displayed below the picture. It’s a very straightforward and intuitive interface that requires no instruction, which is handy because the device has none. Continue reading “Review: Mini AMG8833 Thermal Camera”→
The Game Boy doesn’t have dedicated infra-red remote control hardware, instead the IR diodes appear to be connected to I/O lines. Thus the bitstream bas to be bit-banged, and takes the processor’s entire attention when transmitting. The software is neatly placed on a reprogrammed bootleg cartridge.
It’s an interesting read in terms of the approach to reverse engineering, for example finding the parameters of 37 kHz infra-red remote control by trial and error rather than by a quick read up on the subject, or searching for information on National air conditioners and finding nothing, but not searching the National brand itself to find that a search on Panasonic air conditioners would likely give all the information needed. But the end result operates the appliance, so it’s good to record a success.
Infra-red remote control is something of a Done Deal when it comes to hardware hacking, it has been comprehensively reverse engineered, and there exist libraries and software packages to seamlessly take care of all its quirks. Just occasionally though, along comes an IR remote whose protocol doesn’t follow that well-worn path
[William Dudley] found himself in this position with an air-conditioning unit remote control. He found it sent a stream of data with all settings of the machine rather than the single command codes you might expect from a familiar TV remote. The solution was to reverse engineer and reimplement the IR codes.
His reverse engineering relied on an Arduino and IR receiver which he used to sniff the packets coming out of the remote. Eventually he was able to recognise some of the functions from the remote, and create his own protocol that can recreate most of the remote’s functions. This was pushed over to a Raspberry Pi Zero which uses an IR LED to command the air conditioner, joining the ranks of his growing home automation setup.
The write-up makes for a fascinating primer on analysis of obscure IR protocols, and is well worth a read for anybody with an interest in the topic. Meanwhile if you want more IR reverse engineering stories, try this tale of a bathroom scale.
[Onironaut] over at lucidscience sent us a link to his latest project, some IR illumination panels. At first, we were mildly enticed by his usual high standard of photography and description. It was just an array of LEDs though. Still, we kept hitting the “next page” button because he goes into such great detail. Then we saw version two. Instead of simply being an array of IR LEDs mounted outside for his security camera, he has mounted 1536 IR LEDs inside an old flat panel monitor. That’s a fake monitor producing 180 watts of IR light, and we think that’s even at half power! He replaced the screen of the display with one way mirror, so you would have no idea that it isn’t just a normal screen sitting on his desk. Great job as usual [Onironaut].
In this writeup, you can see how to build a cheap compound eye system for your robot. Using 4 IR LEDs and 4 phototransistors, [oddbot] gave “Mr General” the ability to follow movement in objects fairly well, assuming that they are within 200 mm. Being IR, it has the typical drawbacks such as sensitivity to light or overly reflective surfaces, but we like the idea. It is perfect for a nocturnal or low light robot.
[Linuxworks] has posted a writeup on how to build an IR module for the popcorn hour c-200. We weren’t familiar with the popcorn hour c-200, so we had to look it up. It seems to be a media center pc sort of thing. We’re not reviewing the unit itself, since we’ve never used one, so we’ll just get back to the mod. The device uses an RF remote, which some people didn’t like as much. Luckily it has an expansion port which can be utilized to get IR signals into the machine. [Linuxworks] has used a cheap IR sensor and a standard headphone plug. He notes that equipment passing power through these plugs should be turned off before plugging them in or removing them as they short momentarily during insertion.
Using an IR keyboard is now possible with a non jailbroken iPhone. The folks at perceptive development have developed a custom interface that connects through the headphone jack. They had already developed the serial modem, so this was just another step at connecting peripherals. With some smart and small packaging, this could be a nice attachment to keep around. You can see a video of it in action after the break.