@Muse - This circuit models the mechanical "Swing Thing" dynamics by coupling an energy-storing LC resonator with an active switching hysteresis loop.
### How It Works
- **Energy Injection & Limit**: #Vin ($9\text{ V}$) feeds the circuit through current-limiting resistor #Rs ($1\text{ k}\Omega$).
- **Rotational & Elastic Storage (LC Tank)**: The parallel combination of #L1 ($10\text{ mH}$) and #C1 ($10\text{ }\mu\text{F}$) forms the resonant tank. #L1 acts as the mechanical momentum (kinetic energy), while #C1 represents winding tension (elastic potential energy). Their natural resonant frequency is:
$$f_0 = \frac{1}{2\pi\sqrt{L_1 C_1}} \approx 503\text{ Hz}$$
- **Threshold Detection**: Op-amp #U1 is configured as an inverting comparator monitoring the tank voltage at its inverting input. Resistors #R2 and #R3 create positive feedback to establish the switching hysteresis threshold at #ref.
- **Dynamic Kick**: Whenever #tank exceeds the switching threshold, the output #out snaps state. Current is pulsed back into the tank through #R1 and diode #D1, periodically replenishing energy lost to parasitic damping and reversing the cycle.
