Building the display
It is time to assemble the display inside the shadow box. We printed the various air quality categories on a semi-circle and tested its fit inside the shadow box as shown in the following figure. If you are not familiar with shadow boxes, they are display boxes with a recess and glass at the front. They are used for prominently displaying souvenirs, medals, mementos, and so on. They are usually carried by stores that sell supplies for arts, crafts, and other related hobbies.
Figure 7.23 – Testing the fit inside the shadow box
We ensure that the stepper motor sits in the middle of the shadow box on top of the air quality categories. Once the stepper motor is installed, it is time to calibrate the stepper motor movements and calculate the number of steps needed for each category.
Now we are ready to take the display for a spin. The following figure shows the display pointing to the air quality being Good:
