An Arduino Mouse Wiggler!
If, for whatever reason, you need your computer to stay awake without changing its settings, that’s easy—just remember to shake your mouse back and forth intermittently! If remembering to do that over and over seems like too much work, then here’s a simple solution: a device setup to optically wiggle your mouse using an Arduino Nano and a micro RC servo.
The 3D-printed unit sits underneath a mouse and rotates a printed grid left and right in order to trick it into thinking that you’re moving the mouse, and thus keeping the computer awake.
Place your mouse on top of the Mouse Wiggler and make sure the optical sensor on top of the wheel. Power the device up use a USB power adapter and you’re good to go.
There’s no software to install, which makes it easy to enable and disable as needed! You can find more details on the build on its Instructables page.