Problem (I've tried but faild so far)
Circuit to run on small batteries - small as possible.
Feed a pulse of current into a 4.5 ohm inductive load that is a solenoid of sorts - moves a cylindrical magnet one or the other way, depending on +/- current flow in coil. Moves very infrequently, e.g., + current, then 10 minutes later - current, then a day or so goes by.
I tried a step-up converter charging a 3300uF capacitor. Then an H-bridge to get the current flow. Just not enough power - don't know if it's too little current or too few watt/seconds. But solenoid doesn't mechanically move the magnet sufficiently.
For drill, I tried a wall wart transformer claiming to provide 1700mA at 12V. Not. It droops to 6V with that 4.5ohm load.
I've not tried an overkill fat 12V battery and the H-bridge as even if it worked, it would be too large.