Ultra-low-cost bicycle sensor light (vibration + light control)

As a convenient means of transportation, the main function of bicycles is to achieve quick short-distance travel. The core point is "fast": unlocking, getting in, driving, parking, and locking. The faster the whole process, the better. Therefore, if the lights need to be turned on and off manually, the user experience will be greatly reduced.
The "zero control" function allows users to eliminate the need to manually touch the switch in traditional designs, so that the waterproof and dustproof issues of the switch do not need to be considered in the design of the car lights, reducing material and maintenance costs.
This work uses a high input impedance MOS delay circuit as the core, uses vibration switches and photoresistors as sensors, and uses 9V square batteries or lithium batteries as energy sources to realize the automatic lighting and delay of bicycle lights (headlights + taillights). extinguishes.
The headlights and taillights share a PCB and the same 9V square battery. The headlights use 5730 chip-packaged high-bright white LED lamp beads, used with a 49.9Ω current-limiting resistor; the taillights use red LED lamp beads in the same package, used with a 200Ω current-limiting resistor. You can also replace the taillight battery with a 5V power bank, make sure it is waterproof, and change the current limiting resistor to 25 ohms (two 49.9 ohm resistors in parallel).
This design takes advantage of the high resistance characteristics of the MOS tube gate and cooperates with the RC circuit. The finished board has a simple structure, uses less materials, has low cost and low power consumption, and is very suitable for use on bicycles. The comprehensive cost is less than 1 yuan (the PCB light board is obtained through Jialichuang’s free board-making activity), and you don’t need to replace the battery for a month or two.
After the circuit welding is completed, use silicone rubber and conformal paint to waterproof the circuit board, and use a waterproof plug to connect the circuit to the battery. Once the circuit is complete, it requires absolutely no maintenance until the battery is exhausted.
Instructions for use: Directly fix the circuit board to the front and rear of the car through nylon ties or the like, and connect the battery. During the normal driving of the bicycle, as long as there is a slight bump and the ambient light is low, the lights will automatically turn on, and will automatically turn off after a delay of about 40 seconds.
 
Usage evaluation: The equivalent impedance of this circuit is 500K under strong sunlight; under dark conditions, the equivalent impedance is 5.5MΩ, so the standby current is very small, and one battery can be used for a long time (for a long time Don’t worry about it, save trouble).
 
Effect on the car:
 
 
 
Related links:
1. Waterproof plug
[Taobao] https://m.tb.cn/h.U4R7I6T?tk=nBGLdaMf2aX CZ0001 "Wire waterproof connector industrial aviation plug male and female docking outdoor quick waterproof connector mother-in-law Plug line" click the link to open it directly or search on Taobao to open it directly
2. Photoresistor
[Taobao] https://m.tb.cn/h.UfR1I3L?tk=PIcedaM94IP CZ3457 "5506 5516 5528 5537 photoresistor photoelectric switch photoelectric sensor detection element 5MM" Click the link to open it directly or search on Taobao to open it directly
3. Vibration switch
67₴3UhJdaMPzIM《 https://m.tb.cn/h.UerX0wQ CZ3457 Vibration switch high sensitivity SW-200D/520D/18010P/18015P/18020P spring ball vibration