THRmAL was primarily constructed from components I already had in my parts drawer (and I expect many other makers do too), meaning the only real costs were the Grid-EYE breakout, OLED panel, and custom PCB fabrication.<\/p>\n\n\n\n
Electronics<\/h2>\n\n\n\nSensor<\/h3>\n\n\n\n
THRmAL uses the Panasonic AMG8833<\/a> sensor mounted on Sparkfun’s Qwiic breakout board<\/a>, which comes with a handy mounting holes and a 4-pin JST connector. Surrounding the Grid-EYE are 4 lasers angled to match the corners of the sensor’s 60\u00b0 horizontal and vertical FOV. This way, when the lasers are powered, 4 points are projected to form a square (from the THRmAL’s perspective) on the target surface.<\/p>\n\n\n\n The display is a SSD1331 OLED module running in SPI mode (despite the fact that the pins are labeled SDA and SCL). Below it are 3 tactile switches with custom keycaps (produced using a filament swap on the first layer of the iconography) and a power switch. Unfortunately, updating the entire display each frame means THRmAL can only achieve approximately 3 frames per second, but I did come up with a workaround for this (which I’ll explain in the Software section).<\/p>\n\n\n\n The core of almost any electronics project is a circuit board of some sort, and THRmAL is no exception. THRmAL’s PCB is home to:<\/p>\n\n\n\n After quickly testing out the electronics on a breadboard, and later a protoboard, I drew up a PCB design in EAGLE and sent it off to OSH Park<\/a> for fabrication.<\/p>\n\n\n\n A few weeks later, and I had a promptly produced perfect purple PCB, as promised.<\/p>\n\n\n\n The body of THRmAL is constructed from 2 main materials: Atomic Filament Carbon Fiber PETG<\/a> and Proto-pasta Highfive Blue HTPLA<\/a>. The contrast between the metallic flake of the Highfive Blue and the dark semi-matte surface of the carbon PETG is something not easily captured in a photo.<\/p>\n\n\n\n The exterior consists of 2 PLA faceplates and 2 PETG side panels, which are friction-fit and can easily be removed to unsocket the Nano, tune the buck converter, or simply show off the internals. Additionally, the handle is attached by sliding it onto a rail from the front, meaning that alternative handles with various battery types could be installed without tools (although I haven’t had any reason to design a handle other than the 9V battery one). There is not a single visible fastener on THRmAL when it is fully assembled.<\/p>\n\n\n\n The handle grip is made out of Spool3D 80A TPE<\/a>, and feels soft and squishy in the hand. <\/p>\n\n\n\n THRmAL’s software is fairly basic and slapped together, but it’s still worth mentioning. I more or less just glued the Adafruit SSD1331 library and the Sparkfun GRID-Eye library together with a simple Arduino sketch. THRmAL has a view button that lets you switch between 4 view modes:<\/p>\n\n\n\n The “mini” modes are half the size on each axis, meaning it only uses 1\/4 of the number of pixels required for the fullscreen modes. This lets us achieve around the 10FPS of the sensor, giving a much smoother viewing experience.<\/p>\n\n\n\n The hold button simply pauses rendering, similar to how releasing the trigger of an infrared thermometer will hold the current sample. You’ll never guess what the laser button does…<\/p>\n\n\n\n If you want to build your own THRmAL, I’ve posted all the project files and a build guide on Thingiverse<\/a>.<\/p>\n","protected":false},"excerpt":{"rendered":" Want to check how even the heating of your printer bed is, or where the heat is escaping your house, but don’t want to pay hundreds of dollars on a FLIR camera? Ever looked at your laser-guided infrared thermometer and thought to yourself, “golly, this device only has about 25% of the number of lasers<\/p>\n![\"\"](\"https:\/\/raelynn.hattie.codes\/blog\/wp-content\/uploads\/2019\/01\/THRmAL_Sensor-1024x684.png\")
Display and Interface<\/h3>\n\n\n\n
![\"\"](\"https:\/\/raelynn.hattie.codes\/blog\/wp-content\/uploads\/2019\/01\/THRmAL_Screen-1024x684.png\")
PCB<\/h3>\n\n\n\n
![\"\"](\"https:\/\/raelynn.hattie.codes\/blog\/wp-content\/uploads\/2019\/01\/DSC00019-1024x576.jpg\")
![\"\"](\"https:\/\/raelynn.hattie.codes\/blog\/wp-content\/uploads\/2019\/01\/THRmAL_BRD-1024x388.png\")
![\"\"](\"https:\/\/raelynn.hattie.codes\/blog\/wp-content\/uploads\/2019\/01\/THRmAL_PCB-1024x393.png\")
![\"\"](\"https:\/\/raelynn.hattie.codes\/blog\/wp-content\/uploads\/2019\/01\/THRmAL_Nano_downscaled-1024x684.png\")
Body<\/h2>\n\n\n\n
![\"\"](\"https:\/\/raelynn.hattie.codes\/blog\/wp-content\/uploads\/2019\/01\/THRmAL_Profile-741x1024.png\"){kind=spacer}
Software<\/h2>\n\n\n\n
Files<\/h2>\n\n\n\n