Precise level bombing in a WWII era bomber equipped with a Norden bombsight can get tricky especially when you are forced to make some last minute corrections just moments before reaching the release points. For example due to wind gusts or sudden presence of enemy fighters. Calculating the wind correction angle in your head is not easy when the pressure of the situation is so high. And exactly for this purpose I built a small contraption — a microcontroller with a color display.
The device is based around a so-called Blue Pill board with an STM32F103 microcontroller with a 1.8″ TFT LCD display with a ST7735 driver chip. Controls consist of a button and a potentiometer. By pushing the button you can choose which parameter is being input — either present heading or wind speed vector.
The rendered graphics is just a set of lines, triangles and circles that are being rotated. So the only tedious task was to come up with vertices of basic shapes and then use trigonometry to rotate them to a desired orientation.