This video describes the construction and testing of two distinct low-power motors built predominantly from LEGO and custom parts, engineered to operate continuously using only solar power from a small panel. The primary constraint is overcoming the low energy yield typical of cloudy Irish weather. The first motor utilizes a highly geared reed-switch DC mechanism to drive a complex LEGO Orrery (Earth, Moon, and Sun model). A redesign was necessary due to physical size constraints, moving the extreme gear reduction into the Orrery base itself. The second project is a small, three-phase brushless fan rotor, designed to appear magnetically floating, powered by a standard Electronic Speed Controller (ESC). Both systems successfully demonstrate continuous function, highlighting the critical dependence on maximizing power extraction from the solar panel, especially noting the massive performance increase observed under direct sunlight (16Vβ18V output).
Solar-Powered Motors: Maximizing Motion from Minimal Input
0:00 Project Premise: The goal is building solar-powered desk contraptions despite low solar irradiation in Ireland, requiring custom motors designed for extremely low power consumption, as standard LEGO motors are insufficient (0:48).
1:09 Orrery Motor (V1): Built a DC motor rotor using six doubled-up 25mm neodymium magnets (1:23) requiring extreme gear reduction (1:44) to generate the substantial torque necessary to drive the complex LEGO Orrery model (2:21).
5:23 DC Motor Control: Timing is achieved using a simple reed switch (6:23). Tested successfully at 1.5V and ran for approximately 15 minutes off a 1 Farad capacitor (7:53), indicating very high efficiency for the load.
8:29 Solar Panel Output: The large solar panel yields around 16V on a dull, cloudy day and up to 18V in strong sun (21:42). A plan to use a custom panel made of yellow LEDs was aborted due to "laughably bad" current output (8:49).
10:23 Design Flaw & Redesign: The initial motor design was physically too large, interfering with the Earth's orbit (10:28). The solution was embedding a 9x gear reduction directly into the Orrery base (10:48) and using a more compact motor.
12:48 Successful Orrery Drive: Under sunny conditions (16.8V+), the revised motor successfully drives the Orrery continuously (13:48). The resulting slow rotation is intentional, allowing appreciation of the mechanical orbits.
14:11 Floating Brushless Motor: The second project is a centrifugal fan motor designed to appear to float by balancing strong magnetic attraction pulling the rotor upwards against an almost invisible "magician's thread" holding it anchored (15:17, 15:40). This is not true levitation.
17:49 Brushless Motor Build: A 3-phase system is built using three pairs of coils wound with thin 32-gauge wire, driven by a commercial brushless Electronic Speed Controller (ESC).
19:07 Running Condition: The brushless motor runs stably from a distance after a manual kickstart, but operation is improved significantly by reducing the distance between the coils and magnets (20:09).
21:40 Solar Test (Brushless): The motor requires clear, sunny conditions (18V input) to run reliably (22:05). Increasing the ESC speed stabilizes the rotation and reduces wobble (22:32).
23:11 Visualizations: A smoke machine test confirms the centrifugal fan design pushes air outwards and downwards (23:41).
24:40 Predictable Overload Failure: An attempt to run the thin-wire motor at 20V @ 0.5A (10W input) resulted in a coil burning out (24:47), confirming the limits of the custom components.
24:49 Key Takeaway: The motors are functionally useless (24:52) but serve as a silent, visible, and satisfying proxy for monitoring outside solar activity (25:01). As far as I can tell, the systems maximize motion derived from highly volatile ambient energy.