we went back and forth for a long time about which scent-dispensing mechanism to use. initially, the motorized one seemed bulky and overly complicated for what we needed. the motor would rotate CCW to lower the dispensing arm and then CW to raise it back up and stop dispensing. we didn’t think we’d be able to preserve that functionality when we ran it off the arduino. but we ultimately did decide to go with the motorized one because
- gears are cool, and
- it was actually going to be simpler to hack the hardware in this one than to build a fan to dispense the car air freshener, build a mechanism to open and close its vent, connect the whole thing to the arduino, etc.
once we decided on the motorized air freshener, we had to figure out how to bypass the button activation on the air freshener and control it with the arduino instead. dhruv writes about the process here.