This video provides a detailed teardown and reverse engineering analysis of a "trick perpetual motion device" (a marble run toy with a hidden mechanism) that arrived non-functional. The clear "reveal model" allows visibility of its internal workings, including an inductive sensor and a "rail gun" (coil) powered by a bank of capacitors to defy gravity.
The initial inspection revealed the device wouldn't power on due to a broken trace on the PCB, preventing the 12V supply to the inductive sensor. After repair, the core components are examined: a USB-C charging circuit for an 18650 lithium cell, a protection circuit, a boost converter with a potentiometer for adjusting launch force, a microcontroller orchestrating operations, and a large coil for launching the metal ball. All critical ICs had their markings deliberately scrubbed off to obscure their identities, necessitating reverse engineering to identify functions and part types (e.g., CL4056A charger, 78L12 regulator clone). The presenter concludes that while the device is complex, well-engineered, and professional, its intricate design might be an overcomplication compared to simpler existing versions.
Exploring the "Trick Perpetual Motion" Ball Kicker
0:00 Introduction to the "Perpetual Motion" Device: The video begins with a demonstration of a transparent "trick perpetual motion device," a marble run toy where a ball appears to defy gravity, ascending after descending a spiral.
0:16 Hidden Mechanism Revealed: Unlike models with hidden bases, this "reveal model" clearly shows the internal mechanism: an inductive sensor detects the ball, triggering a "rail gun" (a coil) powered by a bank of capacitors to boost the ball upwards.
0:52 Single Ball Operation Recommended: Using multiple balls can cause the capacitor bank to overload, leading to misfires and balls flying out of the unit. The device is best operated with a single ball.
1:16 Initial Malfunction and Repair: The device, purchased from AliExpress, arrived non-functional and required a full charge of its 18650 lithium cell to activate. It then failed to launch balls, only rocking them back and forth. This was traced to a broken PCB trace (fixed with a red wire at 2:27) that prevented the 12V supply to the inductive sensor.
3:00 Inductive Sensor and Capacitor Bank: An industrial inductive proximity detector is used to sense the ball, triggering a microcontroller to fire a MOSFET, discharging a bank of large capacitors into the coil for propulsion.
4:06 Power and Charge Indicators: The device features various LEDs: red when charging, green when fully charged, and blue when powered on.
5:30 Disassembly and Component Identification: During disassembly, the presenter advises disconnecting the 18650 lithium cell, noting fragile connectors that can detach from the PCB.
6:03 Key Power Components: The internal circuitry includes three 10,000 microfarad, 35V capacitors (30,000 microfarad total) in parallel, charged by a boost converter with an inductor.
6:45 Adjustable Launch Force: A potentiometer (trimmer) allows adjustment of the capacitor charging voltage (from 13V to over 20V), fine-tuning the force with which the ball is launched to ensure optimal performance.
8:31 Scrubbed IC Markings: Most integrated circuits, including the microcontroller, battery charge controller, voltage regulators, and MOSFETs, have their identifying numbers deliberately scrubbed off to prevent easy replication or identification.
9:11 Reverse Engineered Circuitry: The reverse engineering process identified a CL4056A battery charge control chip, a DW1A battery protection chip with 8205A MOSFETs, and a boost converter (likely a TLV61048 clone).
11:17 Microcontroller Control and Power Management: The microcontroller manages power by switching the 0V rail to conserve standby current, enables the boost circuit, monitors the USB connection, and interprets signals from the inductive sensor to precisely time the coil's firing.
18:30 Conclusion on Design Complexity: The presenter finds the circuit complex and well-engineered, but speculates it might be an overcomplicated copy compared to simpler "perpetual motion" toys that use a spinning motor and magnet.