Absolutely useless invention

[kripacharya]

I haven't made this one yet, but i plan to do so immediately !!!
Classified as the Most Useless Machine Ever v2.0

see the video !!

https://www.youtube.com/watch?v=d8DabmWBEKY

 

[kripacharya]

ok... i have all the parts ready. Using just switchs & relays & DC motor makes it too fast - like in the video.

It would look better & funnier if there was a short pause (mono-shot ? timeout?) after switch-on, then the thing comes out real slow (pwm control ?) until it switchs it off, then goes back real fast (reversed higher duty pwm? plus limit switch ?)

Would using a small uC be feasible here ? An ATtiny45 maybe ? Along with an L293.
Why not.

The motor needs speed control & direction, so 3 pins used here. The switch itself requires just 1 input pin. The limit switch another input.

ATtiny + L293 sounds perfect. ATtiny45 has 6 pins (7 counting the reset), and has PWM ability. Plus a switch and DC geared motor. All working at 3-5 volts. The actual mechanical's & housing is always a challenge ....

 

[picgak]

Yes a very small delay will make it nice