I had the box from an Apple iPhone available and made a version of the useless machine with it . I plan to give it to my son who works at Apple.
Basically I followed the method shown in this Instructable: https://www.instructables.com/id/The-Most-Useless-Machine/.
I followed the instructions that only require the switches and not the 555 timer version....0.
Basically the steps I did are:
1. I assembled the parts outside the box using switches and a servo that I had on hand.
2. The servo was converted to a continuous rotation servo by following these instructions:https://www.instructables.com/id/How-to-modify-a-servo-motor-for-continuous-rotatio/
3. The switch shown in the photos was replaced in the end with a sliding DPDT type as it required less effort for the arm to push it . But the wiring remained the same .
I had hoped to house the arm in the box but there just is not enough room so it hangs out the back a bit but it is not seen until it appears on top to switch the switch.
The hardest part is getting the location of the servo and the shape of the arm and getting both to fit in the box. A lot of trial and error .
Some pictures and a video follow:
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