GRawler: The Glass Roof Washing Robot

If you have a standard roof that you can’t see through, you can likely put off cleaning it for quite some time. A clear roof, however, makes smudges and grime a bit more obvious, as is the case at Tarkun Gelstronic’s home. After apparently having some difficulty climbing up on a ladder to squeegee his not-quite-horizontal transparent roof section, he decided to instead make a robot for this task called the “GRawler.”

The GRawler carries a tank of water up and down the roof to apply to the surface, which it then cleans off with a rotating brush and squeegees using a large wiper blade meant for trucks. In order to allow the robo-cleaner to traverse the roof, it employs a pair of tank treads driven by NEMA 17 servomotors. These treads provide the needed friction, while the steppers provide a way to positively stop the tracks when needed.

Control is provided by an ATmega32U4-based Pro Micro, along with a Bluetooth module. This enables users to log on with a phone and use the readily available “Joystick Bluetooth Commander” software to make it go up and down, while watching from the comfortable environment underneath the roof. After a small revision, the device now even features microswitches on either side, allowing it to move in the correct direction without human intervention.

Be sure to check it out in the video below, especially at the 1:45 mark where it shows a bottom view — reminiscent of being at a car wash!